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A TREATISE
W.a.YnitJiihh<ir.
DISEASES OF THE HEART
GREAT VESSELS,
AND ON THE
AFFECTIONS WHICH MAY BE MISTAKEN FOR THEM
comprising the
author's view of the physiology of the heart's action and sounds as demonstrated
by his experiments on the motions and sounds in 1830,
and on the sounds in 1834-5.
BY J. HOPE, M. D. F. R. S.
Of St. George's Hospital ; formerly Senior Physician to the St. Marylebone Infirmary ; Extraordi nary Member, and formerly President, of the Royal Medical Society of Edinburgh, &c.
FIRST AMERICAN FROM THE THIRD LONDON EDITION.
WITH NOTES AND A DETAIL OF RECENT EXPERIMENTS,
BY C. W. PENNOCK, M. D.
\ltending Physiciaji to The Philadelphia. Hospital, Blockley.
PHILADELPHIA:
HASWELT, & JOHNSON, NINTH AND CHESTNUT STREET.
1842.
H*
at
Entered, according to the Act of Congress, in tiie year 1842, by Haswell & Johnson? in the Clerk's Office of the District Court of the Eastern District of Pennsylvania,
Gill.
TO DR. ALEXANDER HANNAY, GLASGOW.
My Dear Hannay —
Little less than twenty years have elapsed since we studied auscultation together as house physicians to the Edinburgh Infirmary. At that time, there were few auscultators and many opponents in the land. We have lived to see these circumstances reversed ; and to you, whose zeal and talents have contributed so powerfully to the change, it must be gratifying to behold this once suspected department of medical science recognised as one of the greatest of discoveries, cultivated with avidity by all classes of our profession, and — what is still better — extensively alleviating the suf- ferings of our fellow-creatures.
To you I am indebted for having first drawn my attention to the sub- ject: to you I wish to inscribe this trilling result of my labours, and inadequate testimony of my esteem.
Hinc (omne)principium, hue refer exitum.
Always, my dear Hannay,
Your sincere friend,
J. HOPE.
13, Lower Seymour-street, May 11, 1839.
PREFACE
TO THE THIRD EDITION
The addition of one third of new matter to the present volume, and the care with which the whole has been revised and corrected, will, I trust, sufficiently prove my respect for the favourable opinion of my professional brethren, as evinced, not in this country only, but also on the European and American continents, by the sale of no less than six or seven editions and translations in as many years.
The additions, including', I hope, some useful original matter, though they pervade every part of the work, will be found principally under the following heads : —
1. The natural sounds of the heart.1 2. The sound of
1 My labours on this subject have been appropriated by a certain gentle- man, who, however, has not the most remote pretensions to them. He says, in the Med. Gaz. for September 1835, p. S18, "In the last number of the Med. Gaz. there is an account of my experiments on the sounds of the heart, extracted from an appendix to Dr. Hope's work on the Diseases of the Heart. The statement of the experiments is correct, as Dr. Hope was pre- sent at the greater part (the whole) of them, and / also sent him the ori- ginal notes." For the facts, see p. 52, and the foot-note.
Several writers and reviewers have been led into the error of ascribing these experiments to the individual alluded to: e. g. Professor Milller, in the translation of his Physiology, part iv. p. 176, and Appendix, p. 1: Dr. Alison, in his Supplement to his Outlines of Physiology, p. 18, 1836, &c.
VI PREFACE.
costal percussion, with or without tinnitus (Laennec's Cliquetis). 3. Murmurs from valvular disease, and the whole subject of particular valvular diagnosis, which will now, I confidently hope, be found one of the most simple and easy departments of auscultation. 4. Murmurs of the heart and arteries independent of organic disease. 5. Venous murmurs. 6. Musical murmurs. 7. Abdominal murmurs, both connected with pregnancy, and otherwise.
8. Tremour or thrill of the heart, arteries, and veins.
9. Signs, general and physical, of pericarditis and endo- pericarditis. 10. Connection of diseases of the heart with apoplexy, palsy, &c. 11. Partial dilatation or real aneu- rism of the heart. 12. The signs, physical and general, and the pulse of softening. 13. Signs of adipose disease of the heart. 14. Aneurisms of the aorta bursting into the pulmonary artery and the right ventricle. 15. Ab- dominal aneurisms. 16. Anaemic, nervous, dyspeptic, plethoric, bilious, and other sympathetic affections of the heart, with their diagnosis. 17. Displacements. 18. The pulses of disease of the heart.
To the complaints made by some, that additions and alterations so considerable have been so tardily published,1 though I have habitually taught most of them to my class and in the hospital for several years, I can only reply by pleading my utter inability, even if there had been the inclination, to devote more than an average share of atten- tion to any one subject ; — an inability which rests upon all those who, to the private distractions of a laborious profes- sion, add the onerous duties of hospital physicians and teachers of the practice of medicine. I can, indeed, truly say, with Senac and others, that I have worked slowly and painfully, inter "tsedia et labores," in fragments of time hardly redeemed from excessive professional engage- ments.
I have studied brevity to the utmost, my object always
1 Except the experiments on the sounds, published in the Appendix to the previous edition, in April, 1335.
PREFACE. Vll
having been, to offer the pith of the whole subject in the smallest possible compass. For this reason, I have avoided the multiplication of prolix cases, — offering no new ones except for the illustration of new points or doctrines. As, however, I have sometimes referred to numbers so large as might seem incredible without explanation, it may be proper to state, once for all, that, out of upwards of 15,000 hospital in and out patients, w^hom I have treated during the last eight years, about seven per cent., as near as I can judge from a rough calculation,1 have laboured under organic disease of the heart, — making a total of 1050 cases, exclusive of those occurring in private practice.
I have in several instances transferred to their proper sources discoveries which, in the first edition, I imagined to have belonged to myself. Any similar oversights in the present edition I shall be happy to rectify, if the authors will oblige me with the information.
I have, on the same principle, and, I trust, with perfect good feeling, ventured to reclaim for my countrymen and self a number of discoveries, which an eminent French writer, probably from unacquaintance with the English language and medical literature, has imagined to have emanated from himself.
Finally, I have added a few plates, which I trust will be found convenient.
I have to express my obligations to Mr. James Freeman for the excellent Alphabetical Index.2
J. H.
1 If I have leisure hereafter to sort these eases, I trust to give the exact per centage.
2 In an Appendix prefixed to this Index will be found the important autopsies of the cases of V . . . ., Esq.. and Goff.
PREFACE
BY THE AMERICAN EDITOR.
In complying with the request to add notes to the first American Edition of Dr. Hope's work on the Diseases of the Heart, the object of the Editor has been twofold; — First, to present such views as were regarded by him as being important, in order more fully to elucidate the pre- sent state of knowledge respecting the pathology of the central organ of the circulation; and, secondly, whilst en- deavouring to supply what he might regard as deficien- cies, not to give superfluous or redundant matter, and thus render the work inconveniently voluminous.
In carrying out these views, it will be seen that the Editor has not restricted himself to the introduction of purely original matter, but, as he was anxious to do full justice to the eminent pathologists with whom any inge- nious or valuable views may have originated, he has pre- ferred using their own language, rather than incur the risk of conveying wrong impressions, either by condensing it, or by clothing their thoughts in other words. Hence, it will be found, that copious extracts from the writings of that most talented and ingenious pathologist, Dr. C. J. B. Williams, are not unfrequent. The valuable investiga- tions of M. Bizot, respecting the dimensions of the heart, have been given in detail. Views respecting certain pa- thological facts derived from the Editor's observations have also been introduced, and a previously undescribed form of Dissecting Aneurism has been illustrated by se-
PREFACE.
veral cases. It has also been thought proper to present the result of " the Experiments on the Heart's Action" which have been instituted since the death of the lamented Author; and as it was supposed that some interest might be had in those performed in this country, the Experi- ments which were made by the Editor and his friend Dr. E. M. Moore, of Rochester, N. Y., have been introduced. The additional matter presented in this edition is in small type within brackets, and bears the initial of the name of the Editor.
C. W. P.
Philadelphia, ) July 1st, 1842. 5
CONTENTS.
Introduction Page 17
PART I.
Anatomy and Physiology of the Heart.
Page CHAPTER I.
Anatomy of the Heart 29
{Situation of the heart 3D
Percussion of the heart 33
Causes which prevent dulness on
percussion 35
CHAPTER II. On the Action and Sounds of the Heart 35
Sect. 1. Ei jx rim mtul Researches on
the Action of the Heart 35
Experiments performed on rabbits
and frogs, July 31, 183!) 3G
Experiments, Aug. 21, 1830 38
Conclusions on the motions of the
heart 42
Conclusions on the sounds 4'3
Conclusions on the rhythm. 43
Experiments repeated, Aujr. 10,
1831 44
Sect. II. Experimental, Physiological and Pathological Researches on
the Sounds of the Heart 48
Experiments, Series i 53
, Series ii 55
, Series iii 56
Conclusions from the whole of the
experiments on the sounds 71
a. Conclusions on the first sound 71
How far it is caused by muscular
extension 73
How far it is caused by bruit mus-
culaire 75
How far it is caused by extension of
the auricular valves 76
I. Conclusions on the second sound. 79 c. Conclusions on murmurs artificial- ly produced 80
Erroneous or defective Theories of
the Sounds of the Heart 80
13— c
CHAPTER III.
Page
Physiological Phenomena of the Heart's Action and Sounds founded on the foregoing Re- searches 83
1. The phenomena of the heart's ac-
tion in the order of their occur- rence 83
2. Causes, mechanism and objects of
the motions 84
3. Causes and mechanism of the
sounds 89
First principle of the heart's mo- tion 91
CHAPTER IV.
Pathological Phenomena of the
Heart's Action and Sounds 92
Sect. I. Modifications of the Motions and Sounds by Hypertrophy and
Dilatation 92
Simple hypertrophy 92
Simple dilatation 93
Hypertrophy with dilatation 94
Sect. II. Murmurs produced by Val- vular Disease 95
Aortic valves; 1. Systolic murmur. 96 2. Diastolic murmur 98 Pulmonic valves; 1. Systolic mur- mur 100
; 2. Diastolic mur- mur 101
Mitral valve; 1. Systolic murmur 101
; 2. Diastolic murmur 103
Tricuspid valve; 1. Systolic murmur 104
; 2. Diastolic murmur 104
Mechanism and varieties of valvu- lar murmurs 105
Continuous murmur in the heart. . 108 Pitch or key of valvular murmurs 109 Musical murmurs in the heart. ... 110 Summary of conclusions on mur- murs in the heart 112
Situations in which murmurs of the respective valves are most
audible 114
1* hope
Xll
CONTENTS.
Page Sect. 111. Murmur from Hypertrophy with Dilatation, and its Mecha- nism 117
Sect. IV. Murmurs in the Heart and Arteries independent of Organic
Disease 118
Laennec's views incorrect 118
Author's views, with proofs 120
Experiments on Dogs 122
Recapitulation of causes 124
Author's views applied to mur- murs, a, from compression of ar- teries 126
b, From loss of blood 127
c, From anaemia, &c 127
d, From arterial varix 128
Musical murmurs not arterial, but
venous 129
Sect. V. Venous or Continuous Mur- mur, Hum, and Musical Notes. ..129
Venous murmur 129
Musical venous murmur 136
Constitutional causes of venous
murmurs 140
Sect. VI. Purring Tremor or Thrill
of the Heart and Arteries 141
1. Jn the heart 141
2. In the arteries 142
3. Inorganic tremors in the arteries 142 Inorganic tremor in the veins. .. 539
CHAPTER V.
Auscultation applied to Preg- nancy 143
1. The double beat of the foetal heart 143
2. The murmur usually called utero-
placental 146
Cases illustrative of murmurs oc- curring in pregnancy, &c 148
Seat of (he murmur of pregnancy. 153 Practical conclusions 155
PART II.
Inflammatory Affections of the Heart and Great Vessels 156
CHAPTER L
On Pericarditis 156
Sect. I. Anatomical Characters of
acute Pericarditis 156
1. Preternatural rednes3 of the peri-
cardium 156
2. Coagulable lymph adhering to the
surface of the pericardium 158
Object of adhesion 159
Process of adhesion 160
Opake white spots on the surface
of the heart 161
Analogous transformations of false
membrane 162
Page 3. Fluid effused within the cavity of
the pericardium 162
Anatomical characters of chronic
pericarditis 163
Sect. II. Signs and Diagnosis of acute
Pericarditis 164
1, General signs 165
Signs of amelioration 1 72
2. Physical signs. Percussion 173
Impulse. Sounds.. 174
Attrition-murmurs. . , 175
Murmurs of coexistent endocardi- tis 180
Diagnosis of valvular from attrition- murmurs. 182
Signs and diagnosis of chronic pe- ricarditis 182
General signs 182
Physical signs 183
Sect. 111. Causes of Pericarditis .... 184 Sect. IV. Progress and Duration, Terminations and Prognosis of
Pericarditis 187
Progress and duration 187
Terminations. 188
Prognosis 188
Sect. V. Treatment of Pericarditis . . 190 Treatment of acute pericarditis.. 190 Treatment of chronic pericarditis. 195 Sect. VI. Adhesion of the Pericar- dium 196
Diagnosis of adhesion 198
CHAPTER II.
Carditis, or Inflammation of the
Muscular Substance 200
1. Universal carditis 200
2. Partial carditis, abscess, ulcer, rup-
ture of walls, valves, aorla, &c. 201
CHAPTER III.
Endocarditis, or Inflammation of the Internal Membrane of the Heart 203
Sect. I. Anatomical Characters of
acute Endocarditis. 206
A. Redness of the internal mem- brane of the heart and arteries... 206
1. Non-inflammatory redness 206
2. Inflammatory redness 210
B. Effusion of lymph on the inter- nal membrane, with thickening
of its substance 210
Concretions of blood from endocar- ditis : 212
Sect. 11. Signs and Diagnosis of En- docarditis 213
General signs 214
Physical signs 216
Sect. III. Causes, Progress and Du- ration, Terminations, Prognosis, and Treatment of Endocarditis . . 218
CONTENTS.
Xlll
Page Causes, progress, duration, and ter- minations 218
Prognosis, treatment 220
CHAPTER IV.
Acute and Chronic Arteritis, and Organic Diseases of the Coats
of Arteries 221
Acute arteritis 221
Chronic arteritis 222
Morbid alterations in the coats of
arteries, and especially the aorta 222 Causes of morbid depositions in the coats of arteries 225
PART III.
Organic Affections on the Heart and Great Vessels 230
CHAPTER I.
Hypertrophy of the Heart 230
Sect. I. Anatomical Characters, wUh Classification and Nomenclature
of Hypertrophy 230
Classification and Nomenclature.. 231 Natural dimensions and weight of
the heart 232
Anatomical characters of hypertro- phy 240
Sect. 11. Mode of formation, with the predisposing and exciting causes
of Hypertrophy 24-1
Mode of formation and predisposing
causes 244
Exciting causes -. 247
Sect. 111. Order of Succession in which the serera! Compartments of the Heart are rendered Hi/per- trophovs by an obstacle before them in the, coarse of the Circula- tion 250
Comparative frequency of the forms and combinations of hypertro- phy * 253
Sect. IV. Pathological effects of Hy- pertrophy 253
Effects of hypertrophy of the left ventricle, and of organic diseases of the heart in general, on the
brai n 25(5
Sect. V. Signs and Diagnosis of Hy- pertrophy 203
General signs 203
J. Palpitation 263
2. Dyspnoea 204
3. Cough 204
4. Haemoptysis SJ65
5. Pulse 265
6. Affections of the head 206
Page
7. Complexion 206
8. Serous infiltration 267
9. Angina cordis 267
General signs of hypertrophy of
the right ventricle 268
General signs of hypertrophy of the
auricles 269
Physical signs. Impulse 269
Sounds 273
Dulness on percus- sion 274
Prominence of the precordial re- gion 275
Sect. VI. Progress, Terminations,
and Prognosis of Hypertrophy . . 275
Progress and termination 275
Prognosis 278
Sect. VII. Treatment of Hypertrophy 278 Appendix to hypertrophy .. . 287
CHAPTER II.
Dilatation of the Heart 288
Sect. I. Anatomical characters with Classification and Nomenclature of Dilatation 288
Sect. II. Mode of formation, with pre- disposing and exciting Causes of Dilatation 293
Sect. III. Pathological effects of Dila- tation and Mode of their Produc- tion 295
Sect. IV. Signs and Diagnosis of
Dilatation 300
General si<nis 300
1. Serous infiltration 30L
2. Discoloration of the face 30L
3. Congestion of the brain 301
4. Injection of the mucous mem-
branes 301
5. Passive hemorrhage 301
6. Congestion and enlargement of the
liver 301
7. Angina of the heart. 302
General signs of dilatation of the
right ventricle 302
General signs of dilatation of the
auricles 303
Physical signs 303
Impulse 303
Sounds 304
Resonance on percussion 307
Physical signs of dilatation of the
auricles 308
Sect. V. Progress. Terminations, and
Prognosis of Dilatation 309
Sect. VI. Treatment of Dilatation.. 310
CHAPTER III.
Partial Dilatationor Real Aneu- rism of the Heart 312
Abstract of Mr. Thui nam's paper . . . 313
XIV
CONTENTS.
;Page
Aneurism of the left ventricle 313
Aneurism of the auricles 321
CHAPTER IV.
Softening of the Heart 321
Anatomical characters of softening. . 321
1. Red softening 323
2. Whitish softening 324
3. Yellow softening 325
Signs and diagnosis of softening. . . . 326
General signs 326
Physical signs 327
Diagnosis 327
Prognosis 328
Treatment 329
Cases of softening 329
CHAPTER V. Induration of the Heart 332
CHAPTER VI.
Adipose and Greasy Degenera- tions of the Heart 333
Excess of fat 333
Greasy degeneration 334
Atrophy and oedema of the adipose
tissue 335
Cases of fatty heart, illustrating the
signs 335
CHAPTER VII.
Osseous, Cartilaginous, and other accidental Productions con- nected with the Muscular Substance of the Heart, and with the Pericardium 338
CHAPTER VIII. Atrophy of the Heart 340
CHAPTER IX.
Diseases of the Valves and Ori- fices of the Heart 341
Sect. I. Anatomical Characters, with predisposing and exciting causes,
of Diseases of the Valves 341
Induration of the mitral valve.... 344
Induration of the aortic valves 347
Induration of the valves at the right
side of the heart 348
Predisposing causes of valvular dis- ease 348
Exciting causes 348
Sect. II. Anatomical characters and causes of Warty Vegetations of
the Valves 349
Sect. III. Pathological effects of Dis-
Page ease of the Valves, and mode of
their Production 354
Sect. IV. Signs, Diagnosis, Progno- sis, and Terminations of Disease
of the Valves 357
General signs of disease of the
valves 357
Pulse in valvular disease 358
in disease of the mitral valve 359
in contraction of the aortic
valves 361
in regurgitation through the
aortic valves 362
in valvular disease of the
right side 362
Pain in valvular disease 363
Progress, Terminations, and Prog- nosis 363
Physical signs 364
Signs of disease of the aortic valves 365
of the pulmonic
valves 368
of the mitral valve 369
of the tricuspid
valve 372
of the arterial and
auricular valves conjointly 372
Diagnosis of valvular from inorga- nic murmurs 372
Unusual and curious sources of
murmurs 375
Sect. V. Cardiac Asthma 376
General doctrine of asthma 376
1. Asthma from chronic dry catarrh. 377
2. Asthma from pituitary catarrh 377
3. Asthma from mucous catarrh 377
4. Asthma from disease of the heart. 378
5. Asthma from spasmodic constric-
tion of the bronchial tubes 378
Cardiac asthma described 379
Asthmatic fit described 381
Sect. VI. Treatment of Valvular Dis- ease 384
Bloodletting 386
Diuretics 387
Purgatives 387
Diaphoretics 388
Emetics 389
Puncturing 389
Setons, Issues and Blisters 390
Expectorants 390
Gases 390
Antispasmodics 391
Stomachics 392
Tonics 393
Diet 393
CHAPTER X.
Aneurism of the Aorta 393
Sect. I. Classification, Nomenclature, Anatomical Characters, and For- mation of Aneurism of the Aorta. 394 Classification.. 394
CONTENTS.
XV
1. Dilatation or enlargement of the
whole circumference of the aorta
2. True aneurism, or lateral, partial,
dilatation of the aorta
3. False aneurism, or aneurism by ul-
ceration of the internal and mid- dle coats
4. Mixed aneurism, or false aneurism
surmounting true
General observations on aneurism
of the aorta
Sect. II. Pathological Effects of Aneu- rism of the Aorta on Contiguous Parts
1. Compression of contiguous parts
2. Destruction of contiguous parts . . Sect. III. Signs and Diagnosis of
Aneurism of the Aorta
General signs
Physical signs
Sounds
Purring tremor
Pulsation
Case of aneurism immediately be- hind the heart
Strong and double jogging impulse
from this cause
Sect. IV. Synopsis of the Physical, in conjunction with the General Signs, in reference to the several varieties of Aneurism of the Aurta
1. Simple dilatation of the arch, and
ascending aorta
Fallacies, and methods of detecting them
2. Dilatation of the pulmonary artery Diagnosis from dilatation and aneu- rism of the aorta
3. Sacculated aneurism of the thora-
cic aorta
Fallacies, and methods of detect- ing them
4. Sacculated aneurism of the abdo-
minal aorta
Fallacies, and methods of detect- ing them
Case of aneurism of the abdominal aorta
Anamic and nervous Pulsation of the Abdominal Aorta
Its physical signs
Its general signs
Aortic Pulsation from Enteric In- flammation
Appendix to Aneurism of the Aorta
Case of aneurismal pouch of the aorta bursting into the right ven- tricle
Case of rupture of a dilated aorta into the pulmonary artery
Signs of aneurism of the origin of
Page 394 39G
398 399 399
403 409 409
413 413 418 419 422 422
423
424
425
425
42G 427
427
428
430
432
434
435 436 43G
43G
437
437 439
Page the aorta opening into the right
ventricle 440
Signs of aneurism of the aorta opening into the pulmonary ar- tery 441
Diagnosis of aneurism of the aorta opening into the right ventricle, or the pulmonary artery from
other diseases 441
Sect. V. Spontaneous Care and Medi- cal Treatment of Aneurism of the Anna, and Treatment of Xcrvous
Pulsation 442
Spontaneous cure 442
Medical treatment 443
Treatment of anaemic and nervous pulsation 448
CHAPTER XI.
Malformations of the Heart.... 44 9
Communication between the two sides of the heart .'•*;•• ^53
General signs of communication between Che sides of the heart. . 455
Physical signs 457
Cases of communication between the two sides of the heart 458
PART IV.
Nervous Affections of the Heart 4GI
Spasms, Convulsions, and Paraly-
4G1
CHAPTER 1.
Xei ralgia of the Heart, or Angina
Pectoris 4GJ
Causes of angina pectoris 4G3
Nerves affected in angina 4G4
Diagnosis 4G5
Treatment 4G5
CHAPTER II.
Palpitation, particularly ner- vous 4G7
Palpitation from inorganic causes, usually called nervous, imitating
disease of the heart 4G8
1. From dyspepsia, hysteria, etc. ... 4G>
2. From anaemia 470
General symptoms of anamiia. . . . 470
Physical signs 471
Treatment of anamiia 472
3. From too stimulant diet 472
4 From plethora 473
Cases illustrative of palpitation. . 472
13— d
1 t hone
XVI
CONTENTS.
Page
Case 1. Dilatation with hypertro- phy; overfeeding; simple apo- plexy 473
Case 2. Dyspeptic and nervous pal- pitation, with dilatation and cere- bral congestion 474
Case 3. Dyspeptic, hypochondria- cal, and nervous palpitation. . . . 475
Case 4. Plethoric dyspepsia, with palpitation 476
Case 5. Plethoric congestion of the heart, with palpitation and slight dyspepsia 476
Case 6. Plethora; dyspepsia; hepa- tic enlargement; jaundice; inter- mission; palpitation; "fulness" of the heart; and fainting 477
Case 7. Plethora; bilious engorge- ment; intermission of the pulse; occasional fainting; great oppres- sion and debility 479
Case 8. Derangement of the sto- mach, bowels, and liver; parox- ysm of palpitation with orthop- nea 480
CHAPTER III.
Syncope 480
Treatment 481
PART V.
Miscellaneous Affections 482
CHAPTER I.
Polypus of the Heart 482
Anatomical characters 483
1. Unorganized polypi 483
Page
2. Slightly organized polypi 483
3. More completely organized polypi 485 Causes and formation of polypous
concretions 485
1. From mechanical retardation of the
circulation 485
2. From inflammation 485
Signs and diagnosis of polypi.... 486
Physical signs 487
General signs 487
Treatment 488
Solubility of polypous concretions 490
CHAPTER II.
Displacements of the Heart 490
Symptoms 491
Diagnosis 491
CHAPTER III.
Hydropericardium 491
Signs and diagnosis 492
Treatment 492
CHAPTER IV.
Pneumopericardium 493
PART VI.
Cases 494
Description of the plates 545
Plates (Figs. 2 to 22, inclusive) . . 552 Plates 1 and 2 of dissecting aneu- rism 552
Table of pulses of disease of the
heart 555
Appendix of the autopsies of
V . . . ., Esq., and Goft* 557
Index of cases 560
Alphabetical index 561
CONTENTS
OF
ADDITIONAL MATTER BY THE AMERICAN EDITOR.
Position of the heart Pa|l
The heart has no fixed relation "to the thorax .' .' .' ! .' .' .' \ ! .' .' .' .' .' .' .' .' .' .' .' .' .' \ \ \ .' '. .' .* 31
Kelative situation of the valves of the heart with the thoracic parietes 32
Experiments of Drs. Pennock and Moore 59
Auricular systolic sound C4. G7. 83. 90
T he second cardiac sound not diminished in simple hypertrophy 93
valvular extension insufficient for the production of the first sound 94
Congestion of the heart affects its sounds 63. 95
llie morbid conditions of the aorta sometimes prevent the formation of the
second sound 97
Cardiac sounds influenced by the state of 'the circulation.' W W W W W ! .' 98
l nickening of the aortic valves causes patescence and abnormal murmurs. ... 99
Kegurgitant murmur at the mitral valve heard near the left nipple 100
^gurgitation through the mitral valve arises sometimes from mental causes 103
■Tricuspid valve does not produce sound from regurgitation, unless diseased 105
Murmur at the tricuspid, where heard f.TT 104
Koughness of the aorta affects the heart's sound 106
Ambiguity of the terms used to express the cardiac sounds 110
Eesions causing different murmurs 112. 1 13
I he flexible stethoscope 117
Feeble pulse caused by regurgitation of blood 118
Dr. Williams's idea of murmurs 122
Cause of the utero-placental murmur 147
Case of utero-placental murmur caused by a tumor 153
Pericarditis may be local . 161
Louis on the lesions in pericarditis 162.163
Hypertrophy and dilatation in consequence of effusion in pericarditis 163
i- ain sometimes referred to epigastrium in pericarditis 165
Pericarditis often latent . . 166
Value of the sign of dulness on percussion in pericarditis 171
Outline of the space which is dull on percussion in pericarditis, is similar to
shape of the pericardium 172
Respiration absent over the praacordial space when much effusion exists in pe- ricardium , 173
Friction sound of pericarditis .' .' .' .' .* .' .' .' .' .' .' .' .' .* .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' . ... 175
nwn S°Und of Pericarditjs, double 177
L)r -Williams's idea of the "jogging motion " in pericarditis 179
M. Jjouillaud's views, respecting the connexion of articular rheumatism
with pen- and endo-carditis, adopted by the American auscultators 185
prognosis favourable in uncomplicated pericarditis 190
1 opical depletion in mild cases of pericarditis 195
Ur. Hallowell, on rupture of the heart 202
^violences of inflammation of the endocardium 212
tmoocarditis associated with acute rheumatism its signs 217
lo produce abnormal murmurs, greater lesions requisite at the aortic than at
the mitral valves . 219
Normal weight of the heart ...'.' " .* .* .* .' * * " ' " ! .* ' ' * .' " ' .WW *.*.'.'.' .' 233
M. Bizot's researches on the dimensions of the heart 234
Dimensions of the heart, in reference to age 235
XV111 CONTENTS.
Page
The heart increases in size in proportion to age 236
Dimensions of the heart, relatively to the height of the individual 236
breadth of the shoulders 237
■ capacity of the ventricles 237. 238
thickness of the left ventricle 238
to the thickness of the inter- ventri- cular septum • • • • 239
Thickness of the walls of the right ventricle 239
Comparative thickness of the walls of the right and left ventricle in the two
sexes • • • • 239
Professor Andral's views of the size of the infantile heart, erroneous. . . . 240
The measure of the right ventricle which indicates hypertrophy 240
The character of the muscular tissue of the heart changed in hypertrophy.. . 240
Elongated hypertrophy of the heart 242
Hypertrophy and dilatation often arise from the same causes 247
Hypertrophy, not necessarily connected with valvular disease 250
Dilated hypertrophy of the right ventricle connected with contracted hyper- trophy of the left 252
Pathological effects of hypertrophy upon the general system 262
Character of the dulness on percussion, variable as regards the space, and
situation 271
Impulse of the heart, influenced by the compartment affected 272
Respiration exists over the precordial region, even when that space may be
prominent 275
Treatment of hypertrophy 286
Measurement of the cardiac orifices 290
. by M. Bouillaud 290
—by M. Bizot 290. 291
Measurement of cardiac orifices acording to the age and sex 290
the right cardiac orifices 291
circumference of the aortic orifice 291
' pulmonary artery 291
Tissue of the heart changed in dilatation 295
Regurgitation through the right auriculo-ventricular orifice in dilatation. . . . 302
Articulate symbols for the sounds of the heart 307
Extent of dulness on percussion, and seat of impulse changed in hypertro- phy, &c 308
Double pulsation accompanying dilated auricles 308
Apoplexy of the heart 313
Aneurism of the valves of the heart 321
Softening of the heart 328
Induration of the heart: Bertin and Bouillaud's views 332
Heart, overloaded with fat 333. 335
CEdema of the heart 335
Symptoms of abnormal cardiac productions 340
Obstructive and regurgitant lesions of the valves 351. 354
Disease of the valves of the left portion of the heart, most frequent 356
The period of the heart's action in which the morbid sounds are generated 365
Obstructive disease of the aortic orifice 366
Duration of murmur in the second sound 367
Combined obstructive and regurgitant lesions of the aortic orifice 367
General symptoms of disease of the aortic valves 368
Regurgitant lesions of the mitral valve * 370
General symptoms of disease of the mitral valve 372
Inorganic murmurs often heard over the apex of the heart 373
Dissecting aneurism 394
Cases of dissecting aneurism 402
Dulness of percussion along the margin of the sternum in aneurism of the
aorta . . ... 426
Dr. Worthington's case of cyanosis 451
Professor Dunglison's remarks on cyanosis.. .' 451
Case of angina pectoris 462
ITY
'ZC
INTRODUCTION
TO THE FIRST EDITION
Preceded by names so distinguished as those of Corvisart, Kreysig, Barns, Laennec, and Bertin, I am sensible that I expose myself to the imputation of presumption, in offering to the profession a new treatise on the diseases of the heart and great vessels. I feel called upon, therefore, to explain, in a more circumstantial manner than I should otherwise have wished, the motives which have induced me to undertake this work, and the plan which I have pursued in its execution. Whether I am justified in the attempt 1 can scarcely form an opinion. Every author contrives, I believe, to persuade himself that the work which consumes his own midnight oil, is precisely the one that is wanted. It is for the reader to determine whether I labour under the delusion common to my brethren.
Notwithstanding the strong light diffused over the diseases of the heart by the researches of the above mentioned authors, — notwith- standing the brilliant sunshine emanating from the discovery of auscultation by Laennec, — a discovery, which, according to M. Bertin, " has, in a few years; more completely illumined the dia- gnosis of the diseases in question, than all the other modes of explo- ration had done for two centuries-/' the great body of the profession still deny that the piercing ray has reached its destination, still doubt the utility of auscultation in reference to the primary organ of the circulation, still find the ordinary symptoms beset with their accustomed difficulties, still complain, in short, that the obscurity which involves the diseases of which we speak, is scarcely less profound than ever;1 and, while conflicting opinions are embar-
1 A distinguished Frenchman recently said to me, " Monsieur, je ne crois pas, pour vous dire la verite, que 1'on puisse en faire le diagnostic — que sur la table du salon."
8— d 2 hope
18 HOPE ON DISEASES OF THE HEART.
rassing the judgment, and undermining the confidence of the patient investigator of truth, there is a general outcry for an additional mass of well-attested evidence, which may bring the subject to some kind of a conclusion.
It rarely happens that a general impression is wholly unfounded: nor is it, if I mistake not, in the present instance. Authors actually have not succeeded in completely redeeming this subject from its obscurity. Errors remained to be corrected, deficiencies to be sup- plied, inconsistencies to be reconciled: the subject — a confused and incongruous mass — required to be moulded and compacted into a symmetrical and harmonious whole, the parts of which, while per- fect in themselves, should, by their justness of proportion and unity of design, afford relief and support to each other.
I proceed to glance briefly at the subjects where the principal defects appear to have resided ; and this I do, not only for the pur- pose of general guidance to the student, but also for that of pointing out where I have differed from preceding writers.1 In these dif- ferences, I am anxious to offer my opinions, not as established facts, though I trust that they will be found grounded on careful obser- vation, but simply as propositions to be admitted or rejected accord- ing to the test of general experience. I am satisfied that, in our profession more especially, where there are few fixed points to con- stitute the basis of an inductive process, nothing is more difficult to ascertain than a general fact. Innovations, therefore, cannot be regarded with too much suspicion, cannot be scrutinised with too much severity, cannot be received with too much caution and reserve."
The most prominent error which reigns throughout the doctrines of Laennec, and which has prevailed in the schools since the first publication of his work, is, that he mistook the nature of the action of the heart. I trust that the view which I have ventured to sub- stitute may be found more satisfactory; and, as nearly a year and a half has elapsed since I first published my experiments and cli- nical observations relative to it : as my conclusions have, through- out that period, remained, so far as I can judge, uninvalidated ; and as I have recently repeated the experiments with the same results, before a number of the most distinguished physiologists and patho- logists of the metropolis ; 3 I hope I shall not be considered preci- pitate in having taken the decisive step of modifying and explaining all the physical signs of disease of the heart according to the view in question.
Laennec and his predecessors have assigned to diseases of the heart a certain series of symptoms, which they conceived to be
1 The further defects, which have been supplied in the present edition, arc briefly enumerated in the preface.
2 Vid. p. 36, 38 and 44. To these may now be added, my experiments on the sounds in 1835, detailed at p. 48 et seq.
INTRODUCTION. 19
common to the whole; but they had not analysed those symptoms, and ascertained which were peculiar to, and pathognomic of, the several affections taken individually. MM. Bertin and Bouillaud, both writers of high talent, made this attempt, and with partial success ; but the spirit of generalisation (if I am correct in my own views) carried them a grade too far. What observation leads me to regard as an inaccuracy, constitutes the hinge of their work — the pivot on which turns the principal train of their reasoning : namely, that the symptoms of a retarded circulation are, under all circumstances, the result of a mechanical obstacle to the course of the blood : — that when, for instance, they accompany hypertrophy or dilatation, they are not consequences of these affections, but of some co-existent mechanical obstacle, as a contracted valve, an aortic aneurism, &c. I have attempted to show, not only that hy- pertrophy, dilatation, and softening can, of themselves, respectively occasion the symptoms in question ; but, that these symptoms are seldom produced in any very remarkable degree of severity by a mechanical obstacle, unless hypertrophy, dilatation, or softening of the heart is superadded. x
It may naturally be supposed that the erroneous view which Laennec took of the heart's action, led to corresponding errors in his doctrines of auscultation. The errors are principally those of omission and of incorrect explanation. The omissions are consi- derable and important. He was not aware of a fact first noticed by the writer in June 1825, namely, that murmurs are produced by regurgitation through the valves. This oversight alone naturally shook the confidence of many, and eventually of himself, in his theory of valvular murmurs. For, the lesion being found in one valve, when, according to that theory, it was expected in another, the inevitable conclusion was, that the theory was incorrect. At the same time, the cause of the murmur remained doubtful.
The perplexity was further increased by the existence of mur- murs independent of valvular disease, and accompanying anaemic and nervous palpitation without any organic lesion whatever. These murmurs Laennec attributed to a wrong cause: viz. to the sound of the muscular contraction, instead of to the modified mo- tion of the fluid ; which I presume to consider the true cause. Hence, he was unable to analyse and foresee the circumstances under which nervous and anaemic murmurs should occur, and,
1 M. Bouillaud complains that I have misrepresented his opinions in the above paragraph. With the utmost anxiety to correct my mistake and make ample amends, I have thoroughly and carefully examined his work in 1824 and that in. 1835, and I am sorry to say that I cannot detect any just foundation tor his complaint. I have shown in section iii. i?ifra, by quotations and references, that he really entertained the opinions which I have ascribed to him, and that he still maintains the same in his later work.
2*
20 HOPE ON DISEASES OF THE HEART.
consequently, to distinguish them from those occasioned by valvular disease.
Several minor phenomena likewise, as the purring tremor, and the arterial thrill and bellows-murmur, he was, in consequence of the confusion created by the error in question, equally unable to explain. Hence, he vaguely attributed them to some unknown " modification of the nervous action."
It cannot be a subject of surprise that, with the above opinions, acquired chiefly during the latter period of his life, he should have retracted, in his second edition, the much more accurate doctrines respecting murmurs as signs of valvular disease, which he had advanced in his first; — transmitting to his disciples the confusion which reigned in his own mind, but which, like the storm that, in tropic climes, is the precursor of the purest, brightest weather, must, sooner or later, had his life been spared, have rolled away before the irresistible force of his purifying and enlightening genius.
The murmurs attending valvular disease, nervous palpitation, reaction from loss of blood, and anaemic or chlorotic palpitation in general ; also the allied phenomena of purring tremor, and arterial thrill, throb, and murmur,1 I have attributed to modifications in the motion of the blood, and explained according to the laws of hydraulics and acoustics. In this way, not only may organic dis- eases of the heart be readily and certainly distinguished from ner- vous and other affections wearing their aspect, but, with attention to certain rules which I have offered respecting the situations where valvular sounds are to be explored, and to certain corrobora- tions derived from general symptoms, the particular valve diseased may in general be detected with precision. Such, at least, are the conclusions to which I have been brought by a very considerable number of cases, a small proportion of which are appended to this volume.2
1 To these, the venous murmur has been added in the present edition.
2 I am enabled in the present edition to speak much more decidedly even than in the above paragraph, having constructed a code of rules of so sim- ple a nature that the particular valve presenting a murmur, whether from constriction or regurgitation, may be detected with demonstrative certainty in every instance where the murmur is distinct. In Aug. 1828, I tested these rules on four intelligent students of St. George's Hospital, professing to be total strangers to the auscultation of the heart. After employing ten minutes in giving them verbally the explanation appended to the diagrams Fig. 4. A, 4. B, 4. C, I introduced to them six patients presenting five dis- tinct varieties of valvular disease, including the pulmonic. They delivered in writing sixteen diagnoses, of which fourteen w^re perfectly correct, and two only were partially defective (see Med. Gaz. Sept. 1828). I have sub- sequently seen numerous students and various practitioners become practi- cal adepts in the course of a few weeks, by committing the rules and dia- grams to memory and examining fifteen or twenty cases, which I constantly keep accessible in my hospital practice. As an instance of the ease with
INTRODUCTION. 21
The investigations of Laennee on aneurism of the aorta, were limited and inconclusive: accordingly, he remarks that, "of all the severe lesions of the thoracic organs, three alone remain without pathognomonic signs to a practitioner expert in auscultation and percussion, — namely, aneurism of the aorta, pericarditis, and polypi in the heart previous to death." I hope that my attempts to throw light on these subjects, may not be found entirely fruitless. The article on aneurism is the substance, with considerable additions, of a series of essays published in the Lond. Med. Gaz. Aug. 22, 1829, and is founded on nearly forty cases in which the diagnosis was verified by post mortem examination. It was originally the subject of the writer's inaugural dissertation.
The treatment of diseases of the heart offers a spacious field for improvement. Previous to the discovery of auscultation, these maladies could seldom be detected before they were so far advanced as to be incurable; and then was not the time to judge of the efficacy of remedies. Laennee, absorbed in his investigation of the diagnosis, paid comparatively little attention to the treatment. His first edition scarcely alluded to it: in the second it is only curso- rily treated. Bertin and Bouillaud are not more satisfactory, — giving a bold outline of leading principles, such as might be struck out by generalisation in the closet, but seldom descending into those datailed delineations of therapeutic measures, which are essential to the practitioner at the bedside.
Nor are these principles always, perhaps, perfectly sound. Their habit of attributing the symptoms of a retarded circulation, under all circumstances, to one cause only, — a mechanical obstacle, gives a wrong bias to the mind ; and that of entwining inflammation with the cause of almost every organic lesion of the heart or great vessels, is replete with danger to the inexperienced practitioner. While I feel bound to say this, (for it is the duty of a writer to point out the path which is insecure, no less than that which is safe,) let me not be supposed to detract from the singular merits of these authors: let me offer my tribute of admiration to the talent which shines through every page of their elegant and scientific work, and acknowledge the extensive obligations that I owe it in the execution of my own.1
which a student will unravel the most complex case, the reader is referred to the case of GofF.
The utility of particular valvular diagnosis is explained hereafter, in chap, ix. sect, iv., in treating of the diseases of the valves.
1 M. Bouillaud has dwelt little more on the treatment in his Treatise in 1835, than in his previous work. For instance, he dismisses so important a subject as hypertrophy in two pages, and to dilatation he gives three lines! His treatment of the worst cases of hypertrophy by the profuse bleeding system of Albertini and Valsalva, is not only strongly objectionable for the reasons specified, chap. i. sect, vii., but is singularly inconsistent in a writer who has insisted so strenuously on palpitation being produced by anaemia! My
22 HOPE ON DISEASES OF THE HEART.
Coqscious of the gap that was presented in the treatment of dis- eases of the heart, I have devoted more attention to this than to any other department of the subject: availing myself, in particular, of the wide and favourable sphere for observation, afforded by a long residence as House Physician and Surgeon successively, in the Royal Infirmary of Edinburgh ; where living, literally, I may say, as well as figuratively, at the bedside of the patient, I had an opportunity of closely watching every habitude and phasis of the disease — every operation and effect of remedies. The results of these researches were submitted in a memoir to the Royal Medical Society of Edinburgh, in the year 1824-5.
Many think that the expectation of effecting an improvement in the treatment of diseases of the heart, is chimerical: and they think so because, not being accustomed to recognise the diseases in ques- tion before they have attained an advanced stage, they are pre- occupied with the old and popular idea of their incurability. To such it might, perhaps, be a sufficiently philosophical answer to reply, that an improved knowledge of the nature and causes of a disease must alone necessarily lead to an improvement in the treat- ment; and that therapeutic weapons are dangerous when wielded in the dark. But here we may go much farther : we may say that, by the improved means of diagnosis, the maladies under considera- tion may be recognised, not only in their advanced but in their incipient stages, and even when so slight as to constitute little more than a tendency. We may say, on the grounds of incontestable experience, that, in their early stages, they are, in a large propor- tion of instances, susceptible of a perfect cure ; and that, when not, they may, in general, be so far counteracted as not materially, and sometimes not at all, to curtail the existence of the patient. We may, accordingly, predict that, the term "disease of the heart," which at present sounds like a death knell when uttered by the phy- sician, will hereafter become by familiarity not more alarming than the term asthma, under which it is frequently disguised.
Such are the direct practical improvements to be expected from a better knowledge of diseases of the heart. But there are col- lateral ones of no less magnitude. It has been stated by M. Rich- erand, repeated by Bertin, and echoed by all who are conversant with this class of maladies, that " hypertrophic enlargement of the heart is more closely allied to apoplexy and palsy than the apo- plectic constitution itself." l
Should the hypertrophy be recognised, its effects on the brain
equally strong objections to his extravagant, dangerous, and, after all, inef- ficient and unnecessary bleedings for acute rheumatism and rheumatic inflammation of the heart, are unfolded in chap. i. sect. iv. and vi. on Peri- carditis.
1 This constitution consists, according to the popular idea, in a broad, robust frame, full habit, and florid complexion. It is in general attended with an unusual size and thickness of the heart.
INTRODUCTION. 23
may be counteracted by judicious treatment: should it be over- looked, the patient, with a view to reducing his apoplectic fulness of habit, is ordered smart exercise, which, by increasing the action of the heart, already too powerful, causes a preternatural determi- nation of blood to the brain, and induces the apoplectic or paralytic seizure. According to evidence hereafter to be adduced, the ma- jority of those who are prematurely cut off by apoplexy in the apparent enjoyment of good health, sink under the circumstances described. ■
Again, there are few more common and certain exciting causes of palpitation and difficulty of breathing in disease of the heart, than derangement of the stomach. What happens to the patient in this case? Tracing the attack, in perhaps every instance, to a dyspeptic fit, he naturally concludes that the latter is the cause : that it is ': all indigestion.'*' "Good air, and plenty of exercise,"' are the remedies recommended: the result is an apoplectic seizure. The circum- stance that before the introduction of the new mode of exploring diseases of the heart, they could rarely be detected in their early stages, contributed to the error in question. For, as patients fre- quently recover from the early stages, the recovery was regarded, by those who assumed this class of diseases to be incurable, as a proof that the affection was merely dyspeptic. Hence dyspepsia acquired the reputation of producing certain symptoms, particu- larly in the head, which are in reality foreign to it, being exclu- sively the results of a co-existent disease of the heart.
There prevails another error, the converse of the above — that of mistaking anaemic, nervous, dyspeptic, and other varieties of pal- pitation, for disease of the heart. The frequency of cases of this kind, especially amongst men of studious habits, (and more parti- cularly, I have noticed, among those of my own profession,) is truly surprising: and as it has always been considered difficult, and by many impossible, to distinguish the two affections, the alarm created is sometimes distressing. Having thought this subject of so much importance as to demand a separate article, (see Palpitation,) I shall here only say, that, so far as my own experience enables me to judge, the discrimination may be made with ease and certainty.
An immense proportion of asthmas — and of the most dangerous and distressing cases, result from disease of the heart: the same may be said of dropsies, especially those that are universal. If the cause be overlooked, the asthmatic is harassed with a farrago of inappropriate and unavailing, not to say pernicious, remedies ; and the hydropic is treated with dangerous activity, or for imaginary affections of the liver, the lungs, or the kidneys. On the other hand, if the cause be detected in the incipient stage, by precau-
1 It is shown in the present edition, chap. i. sect, iv., that other diseases of the heart, besides hypertrophy, are causes of apoplexy.
24 HOPE ON DISEASES OF THE HEART.
tionary measures both the one effect and the other may in general be prevented.
In acute rheumatism, there is no more common and formidable source of danger than inflammation of the heart and its investing membranes. Should it be overlooked when existing in a severe form, (and even in that form it is, to those unacquainted with aus- cultation, one of the most obscure and insidious of maladies,) the patient almost invariably dies from the immediate effects of the attack, or becomes a short-lived martyr to an incurable organic disease of the heart.
There is scarcely a disease of the heart, accompanied with ob- struction of the circulation for any considerable period, which is not productive of enlargement of the liver, and, sooner or later, of its ordinary consequence, abdominal dropsy. Yet there are few common facts in medical science less generally known than this intimate connection between the heart and the liver. The dropsy is ascribed to the latter ; the treatment extends not beyond this organ ; the unknown cause continues to reproduce its effect, and the patient, if he obtain relief at all, only obtains it to undergo a speedy relapse. 1
Individuals affected with disease of the heart are peculiarly liable to inflammation of the lungs; and such inflammation, as I have endeavoured strongly to inculcate throughout this volume, is sin- gularly rapid and destructive. Yet if, from ignorance of the state of the heart, free depletion be practised on the ordinary principles, the patient may sink suddenly after the first or second abstraction of blood. I have more than once witnessed this catastrophe, and few practitioners of experience have not seen the same.
In fever and inflammation in general, disease of the heart may impart to the pulse dangerously deceptive characters of hardness, fulness, weakness, or irregularity, and the patient may be bled too much, from the prevalence of the former characters, or too little, from the presence of the latter. 2
Thus it is seen that the practical improvements to be derived
1 Similar remarks often apply to enlargement of the spleen, to hemor- rhage from the stomach connected with congestion either of the liver or the spleen, to bleeding piles dependent on engorgement of the portal system, and occasionally even to uterine hemorrhage.
[The triple lesion of organic change of the heart, liver, and kidneys, is presented in a majority of the cases of diseases of the central organ of the circulation. — P.]
2 I have offered, at the termination of the work, a complete table of the pulses of disease of the heart— the first, I believe, that has ever been at- tempted. They imitate all the pulses of ordinary disease : consequently, unless the practitioner can make allowance for disease of the heart, the pulse is a fallacious criterion of other affections. This appears 10 me to be the main reason why there has been, from time immemorial, so much dis- agreement amongst authors respecting the indications of the pulse and its value as a sign of disease.
INTRODUCTION. 25
from a better knowledge of the diseases of the heart; extend, not to the diseases of this organ alone, but to a multitude of the most formidable maladies incident to the human frame. There is, in short, scarcely an affection with which disease of the heart may not be more or less interwoven ; and "if," to use the language of Senac, "we would not pronounce rashly on an infinity of cases; if we would not harass our patients by noxious and unavailing reme- dies ; if we would not accelerate death by treating certain diseases like others which are entirely different; nor be exposed to the dis- grace of seeing our diagnosis falsified by the results of dissection; finally, if we would not have danger to be imminent, whilst we are under the blind impression that it is remote, we must study the diseases of the heart."
Such appear to be the vacuities left by preceding writers, and such the advantages to be anticipated from their being supplied. It remains for me to explain the plan of the present work, and glance at a few particulars in its execution.
The work is divided into six parts ; I. The Anatomy and Phy- siology. II. Inflammatory affections. III. Organic affections. IV. Nervous affections. V. Miscellaneous affections. VI. Cases. Although every arrangement of diseases of the heart presents con- siderable difficulties, and I am by no means perfectly satisfied with the one which I have adopted, it appears to me preferable to others, because affections of the same class, being thrown together, by jux- taposition reflect light upon each other; nor, at the same time, are the inflammatory and the organic affections in general so intimately connected, as to render their separation impossible without doing violence to the continuity of the subject. The miscellaneous affec- tions are ranged by themselves, because they are not reducible to any of the preceding heads.
In the execution of the work, it has constantly been my aim, by studying the symptoms in connection with the morbid anatomy, to trace the alliance of the two as cause and effect, and thus to reduce them to certain general and intelligible principles, which might not only contribute to future accuracy of observation, but facilitate the registration of so many and so complicated facts in the memory.
As the authenticity of cases and observations is of the first im- portance, I deem it necessary to present a short explanation of the manner in which I have conducted my investigations. Being persuaded that no evidence is so suspicious as that of the senses, because the magnitude of an error is in proportion to the certitude which is supposed to attach to that mode of exploration, it has con- stantly been my endeavour to avail myself of the collective testi- mony of many. Accordingly, I have, for publication, preferred hospital cases, as being the best attested ; I have invariably written the opinions or diagnoses before the death of the patient; have publicly tested them by the results of post mortem examination ;
26 HOPE ON DISEASES OF THE HEART.
have minuted the dissections with the subject before me, and ac- cording to the prevailing opinions of the individuals present; and, generally before laying down my journal, I have annexed such remark as the case suggested, while the circumstances were fresh in my recollection. Finally, I have obtained signatures where a case was very remarkable, or where there appeared a possibility of its being subsequently called in question. The cases appended to this work are nearly verbatim transcripts from journals thus kept;1 and, in order that they might present a just idea of the possibility of detecting disease of the heart, I have not taken them by selection, but, excepting a few, mostly without diagnoses, have introduced the whole of which I took notes in St. George's Hospital within a definite period. They will be found, I believe, to substantiate the view which I have offered of the heart's action—according to which the physical signs are explained ; and, to the practical student of auscultation, by standing in the relation of exercises to a grammar, I entertain hopes that they may prove one of the most acceptable portions of the volume.
The hospital researches alluded to have been conducted at the Royal Infirmary of Edinburgh, as above stated : at St. Bartholo- mew's, London : at La Charite, Paris, where the lessons and re- searches of MM. Chomel,2 Andral, and Louis afforded the most favourable opportunities for auscultation : at the Santo Spirito, Rome: and, finally, at the Marylebone Infirmary and St. George's Hospital, London. From these and private sources I have minuted a greater number of cases than has, I believe, been published by any previous author.
In some parts, I have occasionally introduced repetitions. Thus, in describing the mode in which changes of structure produce their pathological effects, I have glanced at the symptoms ; and in de- scribing the symptoms, I have explained them, where practicable, by the changes of structure. This I have done designedly; for I am satisfied that such is the process of thought which passes through the mind at the bedside and in the post mortem theatre; and a practical work ought to be the transcript of the mind in those two situations. I have, likewise, made occasional repetitions in the treatment with the view of saving the reader the inconvenience of frequent reference.
Wherever the subject was one of original research, or otherwise
1 Except the cases added to the present edition and dated subsequent to 1831.
2 I owe it to the politeness of the French nation in general, and of this gentleman in particular, to state, that he not only granted me the privilege of being one of his clinical assistants; but, as I was engaged in making drawings of morbid structure, he also allowed me the immediate use of the best specimens which his wards afforded, purposely postponing the demon- stration of them to his class till the following morning.
INTRODUCTION. 27
particularly important, I have been circumstantial. Aneurism of the aorta, hypertrophy, the signs of disease of the valves, &c. may be cited as instances.1 Where the subject was known, I have pre- sented those points only, of which I am myself conscious of making use in practice, suppressing many subordinate minutiae, which, though essential to original researches, gradually become super- fluous, in proportion as the alchemic process of generalisation assays, and assigns their full value to leading facts. Accordingly, I must refer the reader to Laennec for many details, which evince the astonishing accuracy and extent of his first researches, but which are no longer requisite for practical purposes. On the sub- ject of the morbid anatomy of the heart I have been minute, — per- haps tediously so; but it has appeared to me necessary, because there is perhaps no organ in the body, of the diseased states of which the generality are less competent judges than of the heart; and this is the source of the frequent and dangerous error of con- founding organic with nervous disease, or of overlooking the for- mer entirely.
I am prepared to expect some dissent from my views respecting asthma as symptomatic of disease of the heart. Being the results of observation, I submit them with confidence, but shall be the first to recant, should they be demonstrated to be erroneous. I learn that M. Rostan entertains similar views, but having completed my manuscript, and thinking nature a sufficient guide. I have refrained from consulting his works.
With respect to the comparative value of the general and phy- sical signs of disease of the heart, it may be said that Laennec rather undervalued the former and over-rated the latter. This was owino; principally to the general signs beinof less perfectly understood when he studied than they have subsequently become in consequence of being investigated with the aid of auscultation. The ardour of his early disciples, who imagined that the physical rendered the general signs superfluous, brought auscultation into some disrepute by the inaccuracy of their diagnosis. But since the stethoscope has taken its proper place as an auxiliary only, and the diagnosis has been founded on the two classes of signs conjointly, auscultation has ranked as a discovery which will immortalise its author and form an epoch in the history of medi- cine.
[Previous to the brilliant researches of Dr. Hope on the heart's action, in 1832, the pathology of the central organ of the circulation was most singu- larly involved in doubt. Pathologists, with but few exceptions, did not hesi- tate to acknowledge their inability to render a positive diagnosis in the cardiac affection, and, if luckily their notions of the patient's disease should be verified by examination after death, it was regarded as a happy circum- stance, rather than as indicating any positive knowledge on the subject. But a new era in medicine commenced when Hope promulgated to the medical
1 Also the sounds of the heart.
28 HOPE ON DISEASES OF THE HEART.
world, his celebrated experiments, which tended so signally to dispel the erroneous views previously entertained. Since that period, this branch of the science has been cultivated with great ardour, and it was soon found, that, although the ideas of our author respecting the physiology of the heart's action were mainly correct, yet, important facts remained to be elucidated. Zealously co-operating with others, he was enabled to correct his first im- pressions, and the result has been the production of a work, which will endear his memory to the medical profession, and place his name high in the list of benefactors of mankind.
This edition, the first presented to the American public, is from the third of the London press, and contains the author's latest views. It is to be re- gretted that some parts have a controversial character, and the American editor, when he first read them, was disposed to suppress them; but further reflection has induced him to offer the entire text as left by the distinguished author. Notes have been presented in this edition, the result of the editor's personal observation, and the occasional introduction of views of writers, who, though deeply versed in the pathology of the heart, have not arrived at precisely the same conclusions with those of the author: amongst these, the talented Dr. C. J. B. Williams claims a prominent place.
The experiments on the heart's action by American observers, and the most recent result of the British investigations, have been introduced after those of the author.— P.]
PART I.
ANATOMY AND PHYSIOLOGY OF THE HEART.
CHAPTER I.
ANATOMY OF THE HEART.
As morbid anatomy and pathology are only comparative states, or the amount of a deviation from the healthy standards of anatomy and physiology, it is essential for these standards to be thoroughly understood, before the morbid deviations can be appreciated. Of the descriptive anatomy of the heart it is not, however, my inten- tion to treat, as this subject presents no obscurity, and as it ought to be studied in much greater detail than is consistent with the plan of the present work. I pretermit, likewise, that portion of the physiology which relates to the arrangement and action of the muscular fibres, referring the reader to Stenon, Wolff, Duncan, Gerdy, and other original sources of information! It may be briefly observed, that some imagine the systole to be effected by the con- traction of a certain set of fibres, and the diastole by that of another; that, in short, the latter, as well as the former, is the result of an active muscular effort. This, however, has not yet been satisfac- torily demonstrated ; and, while awaiting the issue of further re- search, it is perhaps safer, for the present, to attribute the diastole to that power by whicli a muscle reverts from the state of contrac- tion to that of relaxation, and which I shall, for the sake of avoid- ing circumlocution, designate by the title of elasticity.
There is one point, which is generally treated in too cursory a manner by descriptive anatomists, and the thorough knowledge of which is absolutely essential to the study of diseases of the heart. I allude to the relative size of the organ to the whole frame, and of its several compartments to each other. It is ignorance in this re- spect that has for centuries caused thickening, attenuation, enlarge- ment, and diminution to be overlooked, and the symptoms of disease
30 HOPE ON DISEASES OF THE HEART.
of the heart to be attributed to any cause but the legitimate one. As the subject might escape notice if introduced in this place, I have treated' of it immediately before describing the anatomical characters of hypertrophy, where it will be both conspicuous and convenient. The weights and measurements of M. Bouillaud are also added.
A knowledge of the exact situation of the heart is a point of no less importance to the auscultator ; and, though it does not strictly come under the head of anatomy, I shall, for convenience, advert to it here. The drawing opposite to the title-page illustrates the following description.
As the apex and body of the heart are free, while the base, secured by the great vessels, is comparatively, though not abso- lutely, fixed, the organ turns in a slight degree upon its base with each alternate movement of the diaphragm, the descent of the mus- cle causing its longitudinal axis to assume a more vertical position, and the ascent throwing it transversely to the left. It is necessary, therefore, that the auscultator fix upon some given point at the base, which may serve as a mark and guide for his exploration of the situation of the organ. The point which to myself has appear- ed the most certain, is the pulmonary artery. This vessel, near the place where it divaricates into the two trunks distributed to the lungs, bulges, while the subject is horizontal, at the interspace be- tween the second and third left ribs close to the sternum — a circum- stance which, as well as the situation of the other parts of the heart, I have carefully ascertained by forcing needles through the thoracic walls, at given points, into the viscera beneath. The situation of the pulmonary artery was also well displayed by the dilatation of that vessel described in the case of Weatherly. At the spot alluded to, namely, between the second and third left ribs, close to the sternum, the second sound of the heart is louder even than oppo- site to the pulmonic valves themselves. This is simply because the sternum is not interposed; for the sound attains its maximum of intensity when the subject lies inclined to his left side, by which the pulmonary artery is forced as far as possible beyond the outline of the sternum ; and, on the contrary, when he lies inclined to- wards his right side, by which the vessel is drawn under the ster- num, the sound is no longer peculiarly audible between the second and third ribs. I have derived a further confirmation of the same fact from observations made on a patient shown to me by Mr. Mayo. and subsequently on three others, in whom pleuritic effusion in the left cavity of the chest had protruded the heart to the right side of the sternum (see Displacements). Here the sound of the aortic valves was as loud between the second and third ribs on the right side, as that of the pulmonic valves naturally is in the correspond- ing situation on the left. When the patient is in the erect position, the gravitation of the heart straightens. and pulls down the pulmo- nary artery, so that the sound is less audible in the second costal interspace.
A line drawn from the inferior margins of the third ribs across
ANATOMY OF THE HEART. 31
the sternum, passes over the pulmonic valves a little to the left of the mesial line, and those of the aorta are behind them, but about half an inch lower down. From this point the aorta and pulmo- nary artery ascend ; the former inclining slightly to the right, coming in contact with the sternum when it emerges from beneath the pulmonary artery, and following, or perhaps rather exceeding, the mesial line, till it forms its arch; the pulmonary artery, which is, from the first, in contact with the sternum, inclining more con- siderably to the left, until it arrives at the interspace between the second and third ribs above described. A vertical line, coinciding with the left margin of the sternum, has about one third of the heart, consisting of the upper portion of the right ventricle, on its right; and two thirds, composed of the lower portion of the right ventricle and the whole of the left, on its left. The apex beats be- tween the cartilages of the fifth and sixth left ribs, at a point about two inches below the nipple, and one inch on its sternal side.
The lungs descend along the margins of the sternum about two inches apart, and overlap the base of the heart, slightly on the right side, and more extensively on the left: then, receding from each other, they leave a considerable portion of the right ventricle, and a less extent of the lower part of the left, in immediate contact with the thoracic walls.
The right auricle is in front of the heart, at its right side and upper part. One portion of it is overlapped by the right lung, and another, principally the appendix, is in contact with the sternum. The left auricle is situated deeply behind and to the left of the heart at its upper part, opposite to the interval between the carti- lages of the third and fourth ribs. The extremity of the appendix is visible in front, but, when the volume of the heart is natural, it is not in contact with the sternum, being considerably overlapped by the left lung. The auricular orifices are situated opposite to the interspace between the third and fourth ribs, and the right is rather lower down than the left. As, however, the orifices are overlapped by the lungs, the sound of their valves is much less audible imme- diately over them than near the apex of the heart, to which part the sound is conducted by the chorda) tendinea) and columnar car- nea3. The pericardium ascends on the great vessels as high as the commencement of the arch of the aorta, and opposite to the second ribs.
[When the heart of a living animal is exposed, it is seen that its only fixed and stationary point is at the valves of the aorta ; the other large blood- vessels at the base revolve partially around this point, and the body of the heart being free, no fixed relation exists between it and the walls of the tho- rax; but it hangs, in a certain degree, loose, and liable to displacement by changes of posture and by the motions of the chest. It is of the first im- portance, therefore, that the pathologist should be correctly informed as to the precise situation of the semilunar valves of the aorta. Repeated obser- vations made on the dead body have proved, that these valves are pierced, if needles be introduced perpendicular to the plane of the sternum through the middle of that bone opposite the middle of the cartilages of the third ribs ;
32 HOPE ON DISEASES OF THE HEART.
and that, if the wires be passed perpendicular to the tangent of the curved surface of the thorax, between the cartilages of the second and third ribs, half an inch from the left margin of the sternum, the semilunar valves of the pulmonary artery are entered. The aorta, from its origin, curves upwards towards the right, extending between the cartilages of the second and third ribs slightly beyond the right margin of the sternum; at the lower margin of the cartilage of the second right rib, the arch of the aorta commences and inclines to the left, crossing the pulmonary artery where it lies beneath the cartilage of the left second rib, and ascending as high as the first rib, turns downwards. The pulmonary artery, from its origin in contact with the sternum, commences at the left margin of that bone, where it is joined by the cartilage of the third rib, bulges at the interspace between the second and third cartilages close to the sternum, and dips beneath the aorta opposite the junction of the second cartilage and sternum.
The right divisions of the heart, being most superficial, form the greater pait of the anterior surface; the right auricle reaches from the cartilages of the third right rib to that of the sixth; and between the third and fourth, where its extent is the greatest, it extends, laterally, when filled with blood, near one inch and one third to the right of the sternum. About one third of the right ventricle lies beneath the sternum, the remaining two thirds being to the left of that bone ; the septum between the ventricles coincides with the osseous extremities of the third, fourth and fifth ribs, and on the fourth rib is midway between the left margin of the sternum and nipple. A small part, say one fourth, of the left ventricle, presents anteriorly, and when the lungs are separated, a portion of the left auricle is visible between the second and third left ribs two inches from the left margin of the sternum. With the exception of these portions, the whole of the left ventricle and auricle lie posteriorly to the right ventricle; and the entire left divisions, with the ex- ception of a small portion of the base connected with the pulmonary valves of the aorta, lie on the left of the sternum.
In the dead body, the normal situation of the tricuspid valve extends ob- liquely downwards from a point in the middle of the sternum immediately below the third rib, to the right edge of the sternum where that bone is connect- ed with the lower margin of the cartilage of the fifth rib; the mitral valve commences beneath the lower margin of the left third rib, near the junction of its cartilage with its osseous extremity, (two and a half to three inches to the left of the sternum,) and runs slightly downwards, terminating opposite the left edge of the sternum, where it is joined by the upper margin of the carti- lage of the fourth rib. — P.]
When the heart is enlarged, its longitudinal axis becomes placed more transversely, and its lateral diameter is increased. Hence, the right ventricle projects more considerably to the right, some- times under the whole breadth of the sternum ; and the left extends far beyond its usual limits to the left, sometimes elevating by com- pression that portion of the lung which overlaps it; so as to bring nearly its whole surface, and the tip of the auricular appendix, into contact with the walls of the chest. In addition to being broader and placed more transversely, the organ descends lower than natu- ral— its apex sometimes beating between the sixth and seventh ribs, and its pulsation extending to the epigastrium.
When the right auricle is dilated or gorged, it extends upwards and to the right, and comes more extensively in contact with the sternum.
When the pericardium is distended to the utmost with fluid, it
ANATOMY OF THE HEART. 33
forms a pear-shaped bag, the top or narrow extremity of which, when the patient is horizontal, sometimes mounts even above the second rib : its sides are nearly in contact with the sides of the heart, while its front is separated from the anterior surface of the heart, in the dead subject horizontally placed, by two or three inches of interposed fluid.
From the above description, the auscultator will understand in what situations to explore the lesions of the various parts of the heart. In the section on Murmurs from Valvular Disease, it will be shown that this knowledge is rendered available to the de- tection of the individual valvular diseases, by a process so simple as to divest the diagnosis of almost all difficulty.
The situation of the heart witli respect to the exterior is influ- enced by a few other circumstances which remain to be specified.
The heart is, by its own gravitation, withdrawn, in some degree, from the anterior walls of the chest when the subject leans or lies back, especially if inclined a little towards the rig-lit side. The same effect is produced by full inspiration, even in the erect posi- tion. Under these circumstances, as the apex touches the walls by a smaller point of contact, the impulse is weaker; and, as an in- creased thickness of lung, a bad conductor of sound, is interposed, the first sound is duller. On the contrary, when the subject leans forward and a little to the left, the heart, displacing the lung by its gravitation, comes in more than ordinarily extensive contact with the walls of the chest. The same effect is produced by full expira- tion, even in the erect position. Under these circumstances the impulse is stronger, and the first sound louder. The auscultator will know how to avail himself of these facts in the exploration of disease, and will make due allowances in his estimate of the degree of impulse and sound.
The percussion of the organ is so intimately connected with its anatomical relations, that I may perhaps be allowed to sacrifice strictness of arrangement to practical convenience, and advert to the subject at present.
Percussion on the back of one or two fingers, firmly applied to the chest, either on the ribs which is better, or on the intercostal spaces if necessary, is sufficiently delicate for all practical purposes, and is so convenient that I have, for seven or eight years, adopted this, to the exclusion of all other modes of mediate percussion. I must, however, admit, both from having attended the original ex- perimental researches of M. Piorri, and from considerable subse- quent experience, that the plessimeter invented by that gentleman, when lined with wash-leather or cloth to prevent its clacking, is an instrument of perhaps superior nicety, in the hands of one well ac- customed to it.
It is scarcely necessary to say that percussion over a solid, as the
heart where it is in contact with the walls of the chest, elicits a
dead sound ; while that over a body containing air, as the lungs,
stomach, &c, produces a hollow sound. It is less generally known,
8 — e 3 hope
34 HOPE ON DISEASES OF THE HEART.
that a solid beneath a body containing air, as the liver beneath the edge of the lung, the outline of the heart beneath the lung that overlaps it, (fee., may be recognised by a sound intermediate between hollow and dead. Had M. Piorri, to whom this discovery is due, explained the principle of the phenomenon according to the laws of acoustics, he would at once have made it obvious that what has often been regarded as the offspring of his own imagination, was the necessary consequence of an immutable law of nature. Thus, when sonorous vibrations of the air impinge on a non-resonant or inelastic surface, as drapery, they are arrested and the sound be- comes deadened. The pedal and damper of a piano are construct- ed on the same principle, the only difference being, that the check is given to the vibrations of the wires themselves, instead of to those of the air. Thus, when a note is struck, the vibrations continue till the finger is raised from the key, simultaneously with which action the damper falls on the wires, and by arresting their move- ment suspends the sound. By depression of the open pedal, the damper is permanently raised, and the vibrations then continue, whether the finger be removed from the key or not. To apply this principle to percussion of the chest, — sonorous vibrations excited in the lung are arrested when they impinge upon a solid, inelastic body beneath, as the liver, heart, &c. ; hence the sound is speedily deadened or flattened ; in other words, the resonance is of a dull, flat character : whereas, when there is no subjacent solid body, the sonorous vibrations expand freely, and yield a proportionably hollow sound. To elicit these characters distinctly, a loud sound should be produced by strong percussion, and by pressing the fingers or plessimeter firmly down, so as to condense the soft wall of the chest, and render it a better conductor of sound. Having just tried the experiment before several individuals placed at remote parts of a spacious room, I find that they readily distinguish the full, hollow tone of the middle lobe of the lung, the duller intonation of the lung overlapping the heart or liver, and the dead sound of the prseeor- dial region where the heart is in contact with the walls of the chest.
Now, it is the object of cardiac percussion to ascertain the ex- tent of this dead sound or dulness, because, as observation has demonstrated that it increases in proportion to the increased volume of the heart, and vice versa, it indicates with considerable nicety the actual dimensions of the organ. The mode of manipulation which I employ, is to place one finger over the decidedly dead part, and another over the slightly resonant edge of the lung, when, by striking the two fingers alternately, the arched line along which the organ lies in contact with the walls, may be traced with sur- prising accuracy, unless the subject be remarkable for obesity, which obscures the resonance. In females, the mamma may be pushed upwards, which generally leaves the dull portion sufficiently accessible.
The extent of the dull portion in an average-sized adult with a well-proportioned heart, is represented by a circle of one and a half
EXPERIMENTAL RESEARCHES. 35
to two inches in diameter, supposing the individual to stand or lie without protruding the chest, and in a middling state of inspiration.
When the heart is enlarged, as by hypertrophy, dilatation, fat, or even temporarily by congestion, the descent of the lungs being impeded, the dull portion increases and may attain the diameter of three, four, or, in extreme enlargement, even five inches. The cen- tre of the dulness generally lies between the cartilages of the 5th and 6th ribs, but in great enlargement it lies lower, as between the 6th and 7th ribs, because the organ is depressed by its own gravi- tation, except when held up by adhesion of the pericardium. In copious hydropericardium, I have known the dulness ascend under the sternum, in the conical form of the sac, as high as the level of the second rib ; and I have repeatedly traced the gradual descent of the dulness in proportion as the fluid was absorbed.
The causes which may prevent the development of dulness on percussion are, 1. emphysema of the lungs, occasioning their pro- trusion in front of the heart; 2. the chicken-breasted conformation of the chest, especially when connected with spinal gibbosity. Of the latter cause, though not mentioned by authors, I have noticed many instances.
CHAPTER II.
ON THE ACTION AND SOUNDS OF THE HEART. SECTION I. — Experimental Researches on the Action of the Heart.
When the ear or a stethoscope is applied to the prascordial re- gion, two successive sounds, followed by an interval of silence or repose, are distinctly heard. The first, which is synchronous with the impulse, and, in vessels near the heart, with the pulse, is duller and longer, very like that produced by jerking a cord as thick as a swan-quill; the second is shorter, clearer, and smarter, like the flap or click of a bellows-valve, or it is still more closely imitated by lightly tapping the tense knuckle of one hand held close to the ear, with the soft end of a finger of the other. These sounds, though, according to Raciborski. not wholly unknown to Galen, Harvey, Haller, Senac and Corvisart, were first brought into notice by Laen- nec, and were attributed by him, the one to the ventricular, the other to the auricular contraction. His doctrine remained unques- tioned for a period .of eight or ten years, until Mr. Turner, supported by the authority of the old physiologists, Haller, Harvey, Lancisi, &c, pointed out that the auricular contraction, to which Laennec attributed the second sound, preceded the ventricular, and, conse- quently, that his theory was erroneous. Notwithstanding the talent and ingenuity displayed by Mr. Turner in proving this, he was not equally successful in assigning the cause of the second sound;
3*
36 HOPE ON DISEASES OF THE HEART.
and, though various theories were subsequently proposed, of which I shall give a sketch at the end of this subject, the nature of the heart's action remained a mystery, until it was made the subject of a series of experiments instituted by the writer in the summer of 1830, and repeated in that of 1831. l
From experiments on small animals, supported by analogical arguments derived from pathology, I had previously been able to infer the nature of the heart's action, almost as I subsequently found it; but the point required demonstration, and it appeared to me that the only possible mode of effecting this was, by contriving to hear the sounds at the same moment that the actions were in- spected and felt: since thus alone could it be unequivocally ascer- tained with what motions the sounds respectively coincided. Small animals I had found insufficient for the purpose; as, in them, the sounds are too indistinct, the motions too rapid, and the impulse too feeble, to afford satisfactory data. To large animals, therefore, I turned my attention, as presenting the only means likely to lead to a solution of the question.
As many may wish to follow this investigation through all its steps, and to form their own judgment from the data presented, I insert an abstract of the whole of the original experiments, as pub- lished in the Med. Gazette, July 31, and Aug. 21, 1830: and an account of the conclusions presented by a repetition of them on August 10th, 1831. I also insert,, in Section II. of this chapter, my subsequent experiments on the sounds. The young reader may, if he prefer, omit the whole, and pass on to the third chapter.
Experiments, July,3i, 1830.
As, in my opinion, it is impossible to avoid fallacies when the heart is pulsating at the rate of two hundred per minute, I retarded the circulation of the rabbits which I examined, by depriving them of sensibility previous to the operation. Each pulsation was thus resolved into several distinct and successive motions, which it is philosophical to regard as an analysis of the more rapid natural action. Under these circumstances I found the auricle to contract
1 These experiments were performed on the former occasion before Dr. Hewett, Physician to St. George's Hospital; Mr. Smyth, House Surgeon, and Mr. Lane, Lecturer on Anatomy to that institution ; Mr. Oswald Beale; Mr. Frederick Julius, and Messrs. Field, Veterinary Surgeons. On the latter occasion they were performed before Mr. Babington, Surgeon to St. George's ; Dr. Burrow, Lecturer on Medical Jurisprudence to St. Bartholo- mew's; Dr. Clark, Physician to St. George's Infirmary; Dr. Craigie, of Edinburgh; Dr. Elliotson, Physician to St. Thomas's; Messrs. Field, Vete- rinary Surgeons; Mr. H.J.Johnson, House Surgeon to St. George's; Mr. F. Julius, Richmond; Mr. Mayo, Surgeon to the Middlesex Hospital; Mr. Smyth, House Surgeon to St. George:s; Dr. Watson, Professor of Forensic Medicine to King's College, and Physician to the Middlesex Hospital, and Dr. Williams, author of the " Rational Exposition of Auscultation," &c.
Mr. Brodie, who was accidentally absent, favoured me with an account of experiments by himself, which, so far as they went, coincided with my own. See his letter, p. 47.
EXPERIMENTAL RESEARCHES. 37
first — not slowly — but with a motion so rapid as to be almost in- stantaneous ; the moment the fluid reached the ventricle, the latter was seen to start up, evidently by the contraction of its fibres on the fluid which it contained, and not by passive distention. This was more fully proved at a later period of the experiment, when the action of the heart was from time to time suspended, and the ven- tricle lay quiescent, though partially distended with blood; for, then, the auricle often made two or three contractions, which had no stimulant effect on the ventricle ; while a fourth, not more vio- lent than the preceding-, and therefore not injecting more fluid, caused it to spring up in the manner already described. Simulta- neously with the springing up, commenced the retraction of the apex towards the base, by which motion the apex was thrown for- ward, apparently in consequence of the long axis of the heart as- suming a more horizontal position. These actions constituted only the commencement of the ventricular systole: its progress was marked by a further retraction of the apex and an approximation of the sides; while the whole ventricle was elevated further forward, and its long axis rendered still more horizontal, by the auricular distention, which advanced to its maximum in the same progres- sion as the ventricle contracted to its extreme.
On examining the posterior aspect of the heart of a frog when its action was reduced to fifteen or twenty per minute, the whole of the auricle, which had previously been concealed by the ventricle, being now exposed to view, it was found that, for a short space of time, the ventricle lay at rest partially distended with blood; the auricle then contracted with a smart brief motion — but only par- tially contracted, for the sinus venosus was constantly full of blood both in this experiment and those on the rabbit, and whether the circulation was quick or slow. When the auricle had relaxed again, and not till then, the ventricle (stimulated, I conjecture, by the motion, for it certainly was not by distention) was seen suddenly to rise up on its basis, to shorten its fibres, and to expel its contents, which latter action was slowly performed. After the completion of the systole, which was indicated by the pale colour, the diastole took place, and allowed a partial influx of blood, denoted by the return of the red colour ; and in this state the ventricle remained quiescent for a short space, until again stimulated by the auricular contraction. It may be objected to this account, that as the action of the heart was pretcrnatu rally slow, the motions were anormal. We thought, however, that we could discern the same series of ac- tions when the pulsations were forty per minute.1 The Dublin
1 These, and various other experiments detailed in the Lond. Med. Gaz., were performed at Si. George's Hospital, in the presence of a number of the medical officers and other gentlemen attached to that institution. To Mr. Babington, Surgeon to St. George's, Mr. S. Lane, Lecturer on Anatomy to the Hospital, Mr. Smyth, and Mr. H. J. Johnson, House Surgeons, I am greatly indebted for their valuable aid in performing the experiments, and their patient and unbiased scrutiny of the results.
38 HOPE ON DISEASES OF THE HEART.
Committee of the British Association for August 1835 have repeated these experiments on the frog with similar results. They correctly remark, that "in the heart of the frog, the sides of the ventricle are thin, and the cavity is large ; and the increase of thickness of the sides of the ventricle caused by the contraction of its fibres, is more than counterbalanced by the diminution of volume of the ventricle attendant on the expulsion of its contents :" — in other words, the ventricle becomes very small during its systole because its walls are thin, and very large during its diastole because, from the dis- tensibility of the thin walls, its cavity is very capacious. In this way they explain what I have frequently noticed, namely, that "during the diastole of the ventricle, its anterior surface was pro- tuberant and approached the sternum, while its apex drooped towards the spine ; and that during its systole, the anterior surface receded from the sternum, and its apex was slightly turned upwards or towards the sternum." (Exp. 4.)
Experiments, August 21, 1830.
I now proceed to the communication of further experiments, which, corroborated by pathological considerations hereafter to be adduced, will, I trust, be found decisive of the long controverted question respecting the cause of the motions and sounds of the heart.
At the conclusion of my experiments and researches on small animals hitherto detailed, I entertained the following impressions respecting the state of the question : —
That, in small animals, the auricular systole took place imme- diately before the ventricular, and not after, as supposed by Laen- nec, 1 regarded as certain, both from the evidence of my own experiments, and from the concurrent testimony of the old physio- logists. It was to be presumed that the same occurred in larger animals, but it remained to be proved.
That the impulse and first sound were referable to the ventricu- lar, and not to the auricular contraction, I was equally persuaded, 1st, because the pulse, unquestionably the result of the ventricular systole, coincided so closely, in vessels near the heart, with the im- pulse and sound, that these three phenomena did not admit of being ascribed to any but the same cause; 2d, because clinical ob- servations had proved to me, that certain anormal modifications of the heart's impulse and first sound corresponded with certain mor- bid conditions of the ventricular, but not of the auricular parietes.
That the second sound did not depend on the auricular systole, was indubitable; because this preceded the ventricular contraction, whereas the sound followed it.
That it did not depend on the closure of the riuriculo-ventricular valves was equally certain; because the closure of those valves takes place at the commencement of the ventricular contraction, whereas the second sound occurs after its termination. That it was not due to any other action of the auriculo-ventricular valves
EXPERIMENTAL RESEARCHES. 39
was obvious from physical considerations of their anatomical struc- ture. ■
Such were my impressions; but demonstrative proof was want- ing, and it appeared to me that the only possible mode of obtaining it was, by contriving to hear the sound at the same moment that the action of the heart was inspected and felt ; since thus only could it be unequivocally ascertained with what motions the sounds re- spectively coincided. Small animals were obviously insufficient for this purpose, as, in them, the sounds are too indistinct, the mo- tions too rapid, and the impulse too feeble, to afford satisfactory data. To the larger animals, therefore, I at once turned my atten- tion, as presenting the only means likely to lead to a solution of the difficulty.
The whole subject, then, seemed to resolve itself into the follow- ing questions, which I drew out and proposed to my coadjutors, before the operation, as the points for investigation : —
1. Do the auricles contract immediately before the ventricles ?
2. Does an interval occur between the two contractions, or is the succession so rapid as to amount to continuity of action ?
3. Does the ventricular contraction cause the impulse, pulse, and first sound?
4. Do the ventricles contract completely, and do they remain closed and empty, during the interval of repose? Or —
5. Do the ventricles dilate again immediately after their systole : and is this dilatation attended with an influx of blood from the auricles?
6. Is the influx of blood into the ventricles during their diastole the cause of the second sound ? If not —
7. What is the cause of the second sound ?
Experiment I. — An ass, of which the pulse and impulse were forty-eight per minute, was instantaneously deprived of sensation and motion by a smart blow on the head. The trachea was open- ed, a large bellows-pipe introduced, and artificial respiration main- tained; while, at the same time, the left ribs were sawn through
1 In the first edition, November, 1831, was the following passage : ': That the first sound was not ascribable to the retrocession of the semilunar valves, I entertained a strong presumption, from having found the sound unimpaired, though the valves, on one side of the heart at least, were rigid with ossifica- tion ; and the presumption amounted almost to certainty, from my having found the sound not only undiminished, but increased, incases of enormous dilatation of both ventricles, in which it was impossible that the cavities could ever empty themselves ; and where, consequently, the motion of the valves must have been impeded by the constant pressure of fluid on both sides (vid. for instance, case of Lambert)." This reasoning has proved in- correct ; for in the subjoined experiments on the sounds, I have furnished demonstrative proof that the closure of the semilunar valves is the sole cause of the second sound. I quote the above passage to show that 1 was no stran- ger to the valvular theory — though some subsequent writers have thought that the original idea emanated from themselves.
40 HOPE ON DISEASES OF THE HEART.
near the sternum, and forcibly bent back and broken,1 so as widely and completely to expose the heart immediately behind the left shoulder : the whole was accomplished in less than five minutes.
The pericardium was next opened, and the auricles and ventri- cles fully displayed. The action of the heart was at first quick, tumultuous, quivering, and irregular; but after the lapse of about three or four minutes, it became regular and slower. The auricle was now seen to contract first, and the ventricle instantly after- wards; or, in more descriptive language, a slight contractile motion, accompanied with very inconsiderable diminution of volume, was observed to commence in the auricle, and to be propagated rapidly to the ventricle. It was not, however, so quick thaf it could not easily be followed by the eye ; yet it seemed to be rather a conti- nuity of action, than to consist of two consecutive parts.
The ventricular contraction appeared, and was felt by the hand to consist of a sudden energetic jerk, accompanied with a depres- sion of the centre or body of the ventricle. This contraction was heard (through the stethoscope, applied immediately to the organ) to be accompanied by the ventricular sound. A note was accord- ingly dictated,2 that, 1. The ventricular sound was heard whilst the ventricle was seen to contract. At an interval of time equal to that which intervenes between the first and second sounds of the heart, the contraction was followed by a sudden, jerking re-expan- sion or diastole, which appeared to elevate the body of the ventricle more than the previous contraction. Hence one of the party (Mr. Lane) expressed his opinion that it was the diastole, and not the systole, that occasioned the impulse. This opinion rendered it ne- cessary instantly to repeat all our observations. The stethoscope was accordingly resumed, and several times applied by Mr. Field and the writer alternately, each counting one. two, synchronously with the sounds which he heard, and the impulse communicated to his ear ; while others applied their hands to the ventricle, and at the same time inspected its motion. It was now proved, to the perfect satisfaction of Mr. Lane and all present, that the sound one, and the impulse felt by the auscultator, coincided with the visible depression (i. e. contraction) of the ventricle, and the impulse felt by the hand. It was therefore dictated that, 2. When the action of the heart was become slower, (supposed to be about forty per minute,) and was becoming feeble, the ventricular systolic sound and the impulse were heard, seen, and felt, both by the ear and hand, to be simultaneous.
At an early part of the experiment it had been unanimously agreed that the ventricle never contracted fully, though it was then acting with great power. It was, therefore, dictated, that, 3. The ventricular never contracted fully.
1 This plan was adopted in preference 16 cutting, in order to obviate haemorrhage from the intercostal vessels.
2 The notes were written by Mr. F. Julius to the conjoint dictation of the party during the progress, and immediately after the conclusion of each ex- periment; and they were finally revised and signed.
EXPERIMENTAL RESEARCHES. 41
4. It remained apparently full during the interval of repose, (i e. from the conclusion of the diastole to the commencement of the next ventricular contraction.)
On interposing the hand between the apex of the heart and the rib, which had been left above that part, the fingers were struck vigorously by the apex of the ventricle during its systole, at the moment that its body was in the act of retraction. 1
As the action of the heart, after ceasing to be tumultuous, became somewhat feeble, the second sound was never very audible. It was distinctly heard, however, by Mr, Field and the writer; but as the others could not satisfactorily recognise it, a general note was deemed inadmissible, and a by-note only was dictated, the point being reserved for further investigation at the next experiment.
By-note. — Mr. Field and Dr. Hope listened with the stethoscope alternately, and counted one, two, in unison with the sounds which they heard ; while the others saw that one coincided with the ven- tricular systole, and two with its diastole.
This first experiment was not considered conclusive. In con- sequence of the turbulence of the heart's action at first, and its feebleness at last, the time favourable for observation was toe brief; and, consequently, a majority of the party had not complete confi- dence in the accuracy of their observations. This diffidence was shown by the second experiment to be greater than the case warranted.
The second experiment was performed immediately after the first.
Experiment II. — The heart of an ass was exposed to view in the same manner as before, but with still greater celerity. For about a minute only the action was quivering and irregular; it then fell to its natural standard (forty to fifty per minute), became perfectly regular, and the ventricular contraction, as felt by the hand and the stethoscope, was performed with a power which can scarcely be imagined from an examination on the outside of the chest.
Three successive motions — namely, the auricular systole, the ventricular systole, and ventricular diastole — were now distinctly recognised and acknowledged by all who witnessed them. The stethoscope was applied to the ventricle, and the two sounds were clearly and unequivocally heard, even by those who were unac- customed to the instrument. Five gentlemen listened deliberately twice over, and two of them, three times, before it was dictated that, 1st. Drs. Hewett and Hope, and Messrs. Lane, Field, and Cooper, listened successively through the stethoscope applied to
1 This is corroborated by the London Committee of the British Associa- tion repeating these experiments in August, 1836. "A small opening,1' say they, " was made in the cartilages opposite the heart, when the stroke was perceived and felt by the fingers inside and outside the sternum at the same time, with sound, and with considerable pressure upwards against the fin- gers placed between the heart and the cartilages.''
42 HOPE ON DISEASES OP THE HEART.
the ventricle, and severally counted one, hvo, synchronously with the sounds which they heard ; while the others ascertained, by the touch and sight, that the sound one coincided with the ventricular systole, and the sound tioo with its diastole.
This part of the experiment was so deliberately performed that it occupied from ten minutes to a quarter of an hour, as near as could be judged from the whole time expended (from twenty to twenty-five minutes), and each of the experimenters was asked whether he was satisfied, whilst he had still an opportunity of renewing his examination.
It was now submitted to investigation, how the ventricular sys- tole could occasion the impulse; since the body of the organ appeared to recede during that motion. The result was the follow- ing note :
2. While the ear rested on the stethoscope applied to the middle of the ventricle, the impulse was felt by the auscultator to coincide with the systole, notwithstanding that the body of the ventricle appeared to be receding at the moment the impulse took place.
During the course of the experiment the action of the auricle was again examined. Its anterior edge and surface only were in sight, the root and sinus being concealed behind the ventricle. It was noted that —
3. The auricle never emptied itself, and its contraction was always very inconsiderable. The anterior edge and surface were seen to retract with a rather sudden motion ; but as the extent of the motion was very inconsiderable, it had the appearance of being feeble.
The contraction of the auricle was so much less than there was reason to anticipate from the extent of its action in smaller ani- mals, that it was questioned whether it was, in the present in- stance, performed with the natural vigour. The extraordinary power with which the ventricle acted, favoured the affirmative; and as the proportion of the auricle to the ventricle is singularly less in large animals than in small, there is reason to suspect that they perform a less important function in the former.1
The inevitable conclusions deducible from these experiments are, that — ■
Of the Motions of the Heart —
1. The auricles contract so immediately before the ventricles, that the one motion is propagated into the other, almost as if by continuity of action ; yet the motion is not so quick that it cannot readily be traced with the eye.
2. The extent of the auricular contraction is very inconsiderable, probably not amounting to one third of its volume. Hence the
1 In subsequent experiments on younger and smaller asses poisoned with woorara, I found the action of the auricles greater than is here represented — especially during palpitation, where the pulse was accelerated twenty or thirty beats above its ordinary standard.
EXPERIMENTAL RESEARCHES. 43
quantity of blood expelled by it into the ventricle, is much less than its capacity would indicate.1
3. The ventricular contraction is the cause of the impulse against the side; first, because the auricular contraction is too inconsiderable to be capable of producing it; second, because the impulse occurs after the auricular contraction, and simultaneously with the ventricular, as ascertained by the sight and touch; third, because the impulse coincides so accurately with the pulse in arteries near the heart, as not to admit of being ascribed to any but the same cause.
4. It is the apex of the heart which strikes the ribs.
5. The ventricular contraction commences suddenly, but it is prolonged until an instant before the second sound.
6. The ventricles do not appear ever to empty themselves com- pletely.
7. The systole is followed by a diastole, which is an instanta- neous motion, accompanied with an influx of blood from the auricles, by which the ventricles re-expand, but the apex collapses and retires from the side.
8. After the diastole, the ventricles remain quiescent, and in a state of apparently natural fulness without distention, until again stimulated by the succeeding auricular contraction.2
Of the Sounds.
9. The^rs^ sound is caused by the systole of the ventricles.
10. The second sound is occasioned by the diastole of the ventricles.
The immediate causes of the sounds will presently appear in the section on the Sounds.
Of the Rhythm.
Order of succession —
1. The auricular systole.
2. The ventricular systole, the impulse, and the pulse.
3. The ventricular diastole.
1 The preceding note perhaps justifies a belief that the auricular contrac- tion is considerable in palpitation, and is greater in young and small animals.
2 The Dublin Committee of the British Association for August 1S35, have repeated these experiments and come to exactly the same conclusions: viz. 1. " In the heart of warm-blooded animals, the systole of the ventricles follows immediately the systole of the auricular appendices. 2. During the systole of the ventricles, the auricles are distended by blood from the venous trunks. 3. When their systole has ended, the ventricles become lax and flaccid; and blood passes rapidly, but not with force, from the auricles into their cavities. 4. The auricles are never emptied of their blood, and con- tract but Utile on their contents, an active contraction being observable only in their appendices. 6. The ventricles in their systole approach the front of the thorax, and, by their contact and pressure against it, produce the impulse or beat of the heart."
44 HOPE ON DISEASES OF THE HEART.
4. The interval of ventricular repose, towards the termination of which -the auricular systole takes place.
Duration.
This is much the same as indicated by Laennec, viz.
The ventricular systole occupies half the time, or thereabout, of a whole beat.1
The ventricular diastole occupies one fourth, or at most one third.
The interval of repose occupies one fourth, or rather less.
The auricular systole occupies the latter part of the interval of repose.
Experiments repeated, August 10, 1831.
Three asses were successively made the subject of operation, the process being conducted as before. The gentlemen present are enumerated at p. 36. It may be premised that, in consequence of the percussion of the brain not having been, in the first instance, sufficiently smart, the action of the heart was, in all three cases, more or less irregular through the greater part of the experiment, not continuing, as on the former occasions, ten or fifteen minutes almost without the slightest intermission. Notwithstanding, as the action was maintained for an equal, if not longer time, the periods of regular pulsation were sufficiently numerous and prolonged to allow of deliberate examination. The irregularity led to one im- portant discovery which had hitherto escaped me ; namely, that the movements of the ventricles with their corresponding sounds c,on tin lied perfect while the auricles were motionless.
The following queries were circulated to the individuals present a few days previous to the experiments. They were severally read after each of the three experiments, and the answers were the conjoint dictation of the party, partly during the experiments, and partly at the successive recapitulations.
1. Do the ventricular systole, the first sound, the impulse, and the pulse coincide?
A. They coincide perfectly, except that sometimes there appeared to be a barely appreciable interval between the impulse or first motion of the ventricle (as seen, and also felt with the fingers inter- posed between the apex and the ribs) and the pulse in the radial artery under the shoulder.
1 Mr. Bryan, however, performed the following ingenious experiment with a different result. He caused a long tape to pass at a pretty uniform velo- city across a table, and dotted it with ink in a hair.pencil synchronously with each sound of the heart heard through a stethoscope. He found that eleven inches of the tape passed on from the'time of the commencement of the first sound to that of the second, and that twenty-seven inches more passed before the next sound — thirty-eight inches passing during the time of a whole beat. Thus the duration of the ventricular systole is less than one third of that of the whole beat.— Lancet, Jan. 12, 1833.
EXPERIMENTAL RESEARCHES. 45
Remark. — The interval alluded to was ascribed to the distance of the artery from the heart. In more remote arteries it is propor- tionably greater, and in those near the heart it does not exist at all.
This subject had, I believe, been examined experimentally by Dr. Stokes and Mr. Hart, of which I was not aware. The fact is now well ascertained. The Dublin Committee of the British Association, Aug. 1835, have illustrated it by a very pretty experi- ment on a calf.
"A tube having been introduced through a puncture in the left ventricle, and one of the mesenteric arteries having been exposed and opened, the jet from the ventricle was observed to precede the jet from the arteries, by an interval easily appreciable. The femoral artery was opened, and a similar observation was made/' (Exp. I.)
2. Do the ventricles expel the whole, or a part only, of their contents; and what is their state during the interval of repose? Are they full or empty?
A. The ventricles not being transparent, it is not demonstrable whether they expel the whole of their contents: but the diminution of their volume by the systole is not in general so great as to con- vey that impression. During the interval of repose they are full, being restored to that state by the diastole. By fnhicss, is not meant distention, this being an ulterior degree.
Remark. — The question whether the ventricles expelled the whole of their contents or not. originated in an opinion, which had been maintained, that they did so, and. by the collision of their internal surfaces, occasioned the second sound. As this sound is proved to result from the diastole, the question becomes redundant, and its determination unimportant.
3. With what motion of what part does the second sound co- incide, and what is its cause? Is it the ventricular diastole ?
A. The second sound coincided with a motion, sensible to the touch and sight, by which the ventricle returned from its systole to the same state, with respect to size, form, and position, as before the systole. This motion was the relaxation or diastole.
4. Do the auricles contract before, or after the ventricles, with respect to the interval of repose?
A. Evidently before, being instantly followed by the ventricular systole. The interval of repose distinctly falls between the ventri- cular diastole and the auricular systole, the repose of the ventricles continuing through the auricular systole to the next ventricular systole. Such were the phenomena observed during the short periods when the motions of the auricles were regular; but, for the most part, there was either no perceptible motion in them, or the motions were irregular and bore no relation whatever to the ventri- cular movements.
Remark. — From subsequent experiments on rabbits, in the per- formance of which I was favoured with the assistance of Dr. Hewett, and Mr. Daniel, Surgeon, of Ramsgate, I am led to believe
46 HOPE ON DISEASES OF THE HEART.
that the irregularity of the heart's action is an incidental circum- stance', dependent on the mode in which the animal is stupified, and artificial respiration maintained: consequently, that it is capable of being obviated. At the suggestion of Sir B. Brodie, I stupified the rabbits in question by inoculating them with woorara poison. In the first experiment, after the expiration of a few minutes, stupefaction took place so suddenly that the action of the heart was irrecoverably extinct before artificial respiration could be established. In a second instance, arrangements having been made to establish it more expeditiously, the action of the heart was main- tained in the greatest perfection, after the cerebral life of the animal had become completely extinct. We now found that, on tempo- rarily suspending the respiration, the heart instantly became gorged, of a black colour, and distended to nearly double its natural size, while its motions were either an irregular, occasional flutter, or were wholly suspended. On resuming the inflation, the motions gradually became more and more frequent, extensive, and regular, while the distention and blackness decreased in the same propor- tion; until, at length, the organ regained its previous colour and dimensions, and beat with its accustomed energy and regularity at the rate of 200 per minute. This process was repeated again and again for nearly an hour; and more than once, the action was renovated, though with difficulty, after both the ventricles and auricles had rested some seconds in a state of complete immobility. Hence it appears that, when the stupefaction is complete, (as it is from woorara poison,) and artificial respiration is adequately main- tained, the action of the heart may be kept regular: and it was from greater success in these two circumstances that, in my first experi- ments on asses, the regularity was so remarkable. The hammer employed had a smaller head, its surface, which was slightly exca- vated, not exceeding an inch in diameter. By this, a corresponding portion of the skull was depressed, whence the extinction of cere- bral life was instantaneous and complete, and thus the performance of artificial respiration was rendered more easy. I mention these particulars, in order that, should it be found necessary to repeat the experiments, an unnecessary destruction of life may be avoided. I may add, that the experiments on the rabbit afforded an instruc- tive exemplification of the manner in which congestion of the heart takes place in excessive dyspncea, in suffocation, and in the agony of death. They also showed how, under these circumstances, both the impulse and sounds, even of the most enlarged heart, may be diminished or become totally extinct. To return from this digression —
5. Do the auricles contract slightly or extensively?
A. Yery slightly, and principally at, their appendix, the motion running vernacularly into the ventricular systole.
Remark. — When several irregular ventricular contractions fol- lowed each other rapidly, the corresponding diastoles were attended with a slight retraction of the auricles, most conspicuous at their
EXPERIMENTAL RESEARCHES. 47
sinuses. This phenomenon proceeded from the increased suction of blood by the ventricles.
6. Are the auricles ever empty, or are they constantly full ?
A. Constantly full, their motions ranging between fulness and distention.
The following dictations formed a corollary.
" The first and second sounds were heard, and the correspond- ing motions (the systolic and diastolic) were felt, while the auricles were not contracting."
Remark. — Had this observation been made in my first experi- ments, it would have superseded the necessity for much reasoning, as it conclusively fixes the sounds, the impulse, and the back-stroke or diastolic shock, on the ventricles.
"When the heart was gorged, towards the conclusion of the experiments, the first sound only was heard. :?
Remark. — At the same time the action was very feeble. This, as in the experiment on the rabbit, displays the cause of the diminu- tion of sound and impulse in suffocative dyspnoea, and on the supervention of death.
Sir B. Brodie, finding himself unable to attend these experiments on the 10th, favoured me with the following communication on the evening of the 9th. If doubt remains on the mind of any respecting the points in my experiments to which his observations refer, they cannot fail to have the weight which attaches to any- thing that proceeds from the pen of this distinguished physiologist.
My dear Sir,
.... With respect to some of your propositions, I think that I can already solve them in a way satisfactory at least to myself. 1. When I was making experiments on the circulation formerly, it appeared to me that the pulse and the systole of the ventricle exactly coincided. 2. It appeared to me that, when the action of the heart was vigorous, the ventricles emptied themselves at each contraction ; but that they did not do so, when the action of the heart was feeble. 3. I never found the auricles completely empty themselves, nor did I, in dogs, rabbits, dec. ever observe in them any regular systole1 corresponding to, and alternating with, that of the ventricles. I often used to observe several slight contrac- tions of the auricle, especially of the appendix of the auricle, for one of the ventricle. In frogs, however, I have a strong recollec- tion that the actions did alternate and correspond, but, not being able to find my notes, I cannot speak positively.
If I were to institute such a series of experiments, I would first stupify the animal by inoculating him with the woorara, or some poison of the same kind. You will observe that when an animal is stupified with the woorara, there is no struggling, and you may maintain the heart's action, by inflating the lungs, for an indefinite
1 Sir B. Brodie's observations were here imperfect.
48 HOPE ON DISEASES OF THE HEART.
period., I have some woorara, and can, T doubt not, furnish you with enough for the experiment.
I am, dear sir, yours very truly,
B. C. Brodie.
The woorara arrived too late for the experiments on the asses. I have already described how well it subsequently answered on a rabbit. Prussic acid was tried on one ass, but the animal recovered from four or five successive .drams given by the mouth, the poison being bad.
SECTION II. — Experimental, Physiological, and Pathological Researches on the
Sounds of the Heart.
Though the experiments detailed in the preceding section fixed the first sound of the heart on the ventricular systole, and the second on the diastole, they did not go far enough to demonstrate the immediate cause of the sounds. In the first edition of this work, and previously in the Med. Gaz. of July 1830, I rejected the view that the second sound was occasioned by the closure of the semilunar valves, for the reasons above explained at page 38, which I subsequently found to be erroneous. I also rejected, as the cause of the first sound, the muscular "sound of rotation" {bruit rotatoire), resembling the rumbling of distant wheels, first described by Wollaston and Erman, and adopted by Laennec, as attending the contraction and braced state of muscles, and Which any one may readily perceive by applying his palm to his ear while he alternately braces and relaxes his arm. (For all the particulars, see Traite de l'Auscult. par Laennec, ii. p. 430, second edition). I rejected this (and I have had no reason to alter my opinion up to the present time), because, after torturing, and seeing others torture, muscles in every conceivable way, I never could succeed in pro- ducing, or thinking that others produced, a sound at all resembling those of the heart, either first or second, in shortness and clearness; for it must not be forgotten that the first sound, as well as the second, is short and clear in naturally thin hearts, and in dilatation of the organ. Nor has M. Bouillaud been more successful. After a great number of experiments, he says, " There is not the least- resemblance between the rotatory sound and the sounds of the heart." Having thus excluded closure of the valves and rotatory rumbling as the causes of the sounds, I too hastily adopted an inferential explanation — that they were occasioned by the motions of the blood. This explanation, never quite satisfactory to myself, because not admitting of direct proof, was soon doubted by the pro- fession. The valvular theory was received by Dr. Billing in May 1832; subsequently by M. Rouanet, who frankly and handsomely avows that he derived the idea from Dr. Carswell in 1831 ; simul- taneously by Mr. Bryan; afterwards by Mr. Carlile, and finally by
EXPERIMENTAL RESEARCHES. 49
M. Bouillaud, who adopted, with slight additions, the theory of Rouanet. To Dr. C. Williams, who had already embraced the theory which referred the sounds to " bruit musculaire," it still appeared that the most simple and satisfactory way of accounting for the first or systolic sound of the heart, was, to refer it to this class of sounds (Rational Exposit. Appendix to 2d edit., p. 199, Sept. 1833); while he was <: inclined to place the seat of the second sound in the parietes of the ventricles rendered momentarily tense by the sudden influx of blood." (Ibid. p. 201.)
Feeling it my duty immediately to correct my explanations, if erroneous, I commenced a new series of hospital researches, on the living and dead subject, in 1832, without, however, being ac- quainted with the particulars of the valvular theories above alluded to, most of which, indeed, had not yet appeared. I cannot refrain from stating that the most able of the papers advocating this view and refuting my own, was published by Mr. Bryan, a sensible and vigorous writer, in the Lancet, August 6, 1833. He employs the bulk of the arguments, and especially a case of my own (Anderson), which had already led me to discard my old theory of the sounds. I was not aware of the existence of this paper till 1838.
By examining a vast number of patients in the St. Mary-le-bone Infirmary, I speedily satisfied myself that the first sound was loudest over (or, as I subsequently found, below) the middle of the ventricles; and the second, over the sigmoid valves, and thence for a few inches upwards; also, that when a healthy subject was faint, the first sound lost its prolongation, and became short and smart like the second; whence I inferred that, in its natural state, it might have a compound cause, viz. the closure of the valves, and the mo- tion of the blood, or the bruit musculaire or rotaloire.
The presumptions, thus offered, that the valves were concerned in the production of the sounds, required corroboration by experi- mental and pathological evidence. Not having succeeded in satis- factorily imitating the second sound by injecting fluids retrograde into the aorta, I tried the expansion of membranes under water, and found that three inches of fine tape, two lines broad, held to the end of a stethoscope, and gently jerked under water, imitated the second sound, both the sounds in dilatation, and the double sound of the foetal heart, to perfection. Hence it was more than probable that the sudden expansion of membranes so small as the sigmoid valves was sufficient to produce such a sound as the second.1
It was not easy to meet with satisfactory pathological cases on this subject; as, to be conclusive, great disease of the valves on both sides of the heart simultaneously, seemed to be required. The case of Anderson was one of this kind; the mitral aperture being
1 M. Rouanet's experiments on membranes, &c. correspond with my own. I tried every variety of membrane in breadth, extent, and thickness; also silk handkerchiefs, cloths, &c.
8— f 4 hope
50 HOPE ON DISEASES OF THE HEART.
about a quarter of an inch, and the tricuspid half an inch in diame- ter ; yet the second sound, though weak, was perfect and without a murmur. Now, hstcl this sound been occasioned merely by the influx of the blood, or any other cause than the sigmoid valves, surely it would have been attended with a murmur.1
R. ST3 Esq. whom I saw in consultation with Dr. Armstrong-, had a prolonged bellows murmur over the sigmoid valves instead of the second sound. On examination, the orifice of the ossified and dilated aorta was found so much enlarged that the valves did not close it; hence resulted a murmur from regurgitation, which extinguished the second sound. But why, it will be said, was the sound not produced by the pulmonic valves? True; therefore, I did not consider the case conclusive. I had elaborate notes of three other similar cases ; but as the patients were living, the evi- dence was still less conclusive. I had, however, notes of the case of Thomas "Wood, in the St. Mary-le-bone Infirmary, Oct. 21, 1834, made by myself and by Mr. Hutchinson, resident surgeon to the institution, separately, attesting that a murmur from regurgitation through the mitral valve completely drowned the first sound in the vicinity of the valve. Whence it might be inferred that a murmur in one set of sigmoid valves might possibly drown the natural sound of the other set. I have subsequently ascertained that, over the valves, this may actually be the case. But the natural sound of one set of sigmoid valves can always be heard by listening two or three inches up the vessel to which that set belongs, as its sound is thus withdrawn from the murmur produced in the other set.
On the whole, therefore, the presumptions were exceedingly strong in favour of the second sound being produced by the sig- moid valves.
The evidence on the first sound, more fully explained in the sequel, led me to establish the following presumptions; viz. that the first sound was compound, consisting, 1. Of the valvular flap; 2. Of an augmentation of this, either from bruit musculaire, or the motion of the fluid, or both ;2 3. Of the prolongation of the sound by bruit ?nusculairet or the motion of the blood.
These presumptions required to be proved. No experiments had hitherto been devised which afforded direct demonstrative proof. M. Bouillaud, one of the last writers on the valvular theory, and who published in 1835, says, "I will begin by avowing that the proofs, direct or experimental, of the theory which we discuss, are almost completely wanting, and probably ever will be want- ing." (Traite,!. p. 133-4). After much reflection, a mode of experimenting on the ass occurred to me in the autumn of 1834,
1 In November, 1837, I saw a case the precise converse of this: namely, both sets of semilunar valves were disabled, and- the second sound was almost completely extinct. These two cases afford as complete pathological evidence on the point as could well be desired.
2 It will presently be seen that another cause, the sound of muscular extension, was the principal source of this augmentation.
EXPERIMENTAL RESEARCHES. 51
which, if practicable, would inevitably, 1 thought, prove conclusive; namely, after denuding- the heart in the manner described at page 39, to work out the following Propositions : —
1. Is the second sound loudest over the sigmoids, and is it so near as to seem produced immediately under the stethoscope?
2. Is the first sound loudest over the two auricular valves re- spectively ; and is it so near as to seem produced immediately under the stethoscope?
3. Place the origins of the aorta and pulmonary artery between the finger and thumb; apply the stethoscope on the heart near the sigmoids; instantly after the ventricular systole, close the arteries, so as to prevent the reflux of the blood and consequent expansion of the valves, and see whether this annihilates the second sound.
4. Relax the fingers during the interval of repose, and see whether this reproduces the second sound at its wrong interval.1
5. Push the knuckle, or the auricle, into each auriculo-ventricu- lar orifice, so as to prevent the expansion of the auricular valves, and see whether this annihilates the first sound.
6. Introduce a bent needle into the aorta, and hold open one or more of the semilunar valves, so as to permit free regurgitation. Notice whether this occasions a murmur with the second sound. The pressure of the aortic system being thus thrown on the ven- tricle, will it close the mitral valves? See whether this annihilates the first sound on that side.
To pave the way for the performance of these experiments on the ass, I first made trial on a rabbit, poisoned with woorara, assisted privately and confidentially by Mr. H. James Johnson, lecturer on anatomy at Kinnerton-street, and one of the proprietors of that theatre. Though the heart acted vigorously for an hour, and we could perfectly hear both sounds by applying the small end of a thin stethoscope, the organ was too diminutive, and its movements too quick, to admit of our appreciating modifications of the sounds.
I then proceeded to a trial on the ass, at Mr. Field's, veterinary surgeon, Nov. 3, 1834. For the purpose of obviating any possible question respecting my title to the experiments as the inventor, I took the precaution on this, as on all former occasions, of putting a written copy of the above Propositions into the hands of the friends invited, — Dr. Da vies, of Broad-street, Dr. C. J. B. Williams, Mr. H. James Johnson, and Mr. Field. My woorara being exhausted, I employed the hammer ; but the instrument being too round-headed and the operator inexpert, the experiment failed, the action of the heart being nearly suspended by the time that the organ was exposed. The valves, indeed, were hooked back and the sounds heard, but with unsatisfactory results. The heart was also cut open, and its contractile movements were observed and listened to: finally, we carefully examined the situations of the valves, and
1 This could never be accomplished.
52 HOPE ON DISEASES OF THE HEART.
practised the hooking of them up, with a view to a renewal of the experiments. I made arrangements to renew them immediately, and also requested, and was favoured with, a fresh supply of woorara by Sir B. Brodie. From unforeseen causes, over which I had no control, the experiments were delayed till the ensuing February. The woorara was then employed, and the heart, when denuded, beat with vigour and regularity about 60 or 70 per minute, and continued so to beat for an hour — affording ample leisure for making the following Observations, which answer to the above Propositions. The observations, with two or three exceptions only, were dictated and written by myself, under correc- tion of the party, during the progress of the experiment. I publish them verbatim from the original manuscript, a rule to which I have always adhered. I therefore disclaim another version with verbal alterations, giving, in my opinion, a slight bias in favour of the exclusive muscular theory, which I believe to be erroneous.1
1 These experiments have been appropriated by a certain gentleman. At their second performance, on November 3, 1S34, I promised him, from friendly motives, the use of them for a forthcoming edition of his book; and immediately before their final performance in February 1835, I permitted him, as he expressed a wish, to become my conjoint associate, and subse- quently lent him my own notes of the experiments, written almost entirely with my own hand. He detained the notes, claimed the experiments, and interdicted me from "pirating" them. An arbitration by Sir B. Brodie, and a final agreement through Dr. Macleod, decided that the experiments were conjoint, and that each should publish them as such. I did so (Appen- dix to second edition, page v): he appropriated them. As he has, by this measure, rejected the participation which I gave him, I resume my exclusive right as the sole inventor. His bold pretensions to the invention (to which he did not contribute directly or indirectly) are annihilated by a comparison of my Propositions with the results and an examination of the date (Nov. 3, 1S34) when those Propositions were placed, in writing, in his hands; not to mention the previous confidential performance of the experiments with Mr. Henry James Johnson.
I am reluctantly compelled to make these remarks in consequence of advantage having been taken of a mistake in Sir B. Brodie's arbitration to show it to my disadvantage. Sir B. Brodie mistook the question, and arbitrated as if I had interdicted the opposite party, and not he .me. Not- withstanding, the result was entirely in my favour; for he decided (as I contended) that the experiments were conjoint, not even questioning my right to publish them: and he further bound the opposite party "carefully to explain what share he (Dr. Hope) had in projecting and planning the experiments in the first instance."
The following is from Dr. Thomas Davies, who assisted at the experi- ment, November 3, 1834.
My dear sir,
I can truly say that, although I had read of the.movements of the valves being the cause of the second sound, yet yours were the first experiments I ever saw or heard of, for the purpose of attempting to prove it. I remain, yours very truly,
Thomas Davies. New Broad-street, July 21st, 1835.
EXPERIMENTAL RESEARCHES. 53
SERIES I.1
Obs. 1. The first sound was perfectly loud and distinct; and it was louder on the body of the ventricles than over the semilunar
valves.
8, Suffolk Place, January 14, 1839. My dear Hope,
I can have no hesitation in stating, that I first assisted you in making some experiments on rabbits, to determine the causes of the sounds of the heart, in the spring of 1830. These experiments were performed in the rooms of the house-surgeons of St. George's Hospital.
The second occasion on which you did me the honour to ask my assist- ance, was in the autumn of 1831, when we operated privately on a rabbit at your own house. On this occasion you produced (to the best of my remem- brance) the paper of " Propositions" to be verified or disproved, which you have enclosed to me, and 1 never doubted that they were your own.
It was November 3, of the same year, that I was again present at a repeti- tion of the former experiments, at Mr. Field's, when the paper, which I believe to have seen previously, was reproduced.
Subsequently to this, my colleagues and myself had the pleasure of placing the dissecting-room in Kinnerton-street at your disposal, for a con- tinuation of the experiments on animals, at the first of which (for there were more than one) I was present, but not at the remainder.
Yours very truly,
Henry James Johnson.
Notwithstanding what precedes, the individual alluded to writes as fol- lows, in the last edition of the Pathology and Diagnosis of Diseases of the Chest, p. 169 : " 1 concluded the Appendix (to the previous edition in 1832) by recommending Dr. Hope to investigate experimentally these points (the sounds of the heart), which were there shown to be doubtful; but his engagements and other circumstances having prevented him from doing so, I lately undertook the task; I made a point of ensuring Dr. Hope's presence and testimony at the experiments, and I conferred with him and several other gentlemen as to the best mode of performing them. I was present at an experiment attempted by Dr. Hope, in November last, at Mr. Field's; and he then planned modes of suspending the action of the valves, similar to some of those afterwards adopted in my experiments." The last sentence was added, I presume, to meet the order in Sir B. Brodie's arbitration. How far it does so, and whether it is not rather an indirect appropriation of the invention of the experiments, the reader can judge.
1 Present — Drs. Arnott and Williams, and Messrs. Babington, Smyth, H. James Johnson, Peregrine, Good. Messrs. Charles Johnson and Tatum were temporarily present.
These experiments were repeated, and republished a year and a half afterwards, by the London Committee of the British Association. They verified the whole, but without eliciting anything new beyond a few illus- trations and corroborations, which I shall append in the form of notes to this and the following series. The sameness is, perhaps, to be ascribed to the circumstance, that one of the committee, who, as Dr. Todd informed me, directed the others in everything, had been present at the whole of my experiments. It was probably from the same cause that the committee adopted the pure muscular theory of the first sound, previously advocated by the same individual, and from which I dissent as being too exclusive.
" The subjects of their observations, say the committee, were, in most instances, young asses, from three to six months old, apparently in good
54
HOPE ON DISEASES OF THE HEART.
2. The second sound was more audible over the semilunar valves than at the other parts of the heart, being sometimes distinct at the mouths of the arteries when inaudible on the body of the ventricles.
3. Pressure on the arterial orifices by the fingers or the stetho- scope invariably stopped the second sound. Slight pressure caused a whizzing or bellows murmur with the first sound. l
4. The first sound was diminished, but not wholly suppressed, by pressing upon the ventricles with the end of the stethoscope (so as to curb or restrict their full contractile tension).
5. At each systole the sudden tension of the ventricles was such as to produce an abrupt shock to the finger placed on any part of them, with which shock the first sound exactly coincided. (This observation was pointed out by the writer). 2
6. The first sound was diminished, but not suspended, by thrust- ing the ends of the fingers into the auriculo-ventricular orifices; the ventricles contracting less, and irregularly (from the impeded influx of blood). 3
7. An incision being made into the left auricle, and the scalpel being passecl into the ventricle, so as partially to destroy the mitral valve, and the blood being allowed freely to escape, the first sound continued to be heard with each contraction of the ventricle. See 9 a.
health; and the mode of operation was, in a few instances, poisoning with woorara ; in others stunning by a blow on the head; but in the majority, the animal was pithed."
The successful experiments were fourteen in number, but the committee say that they were " much less fortunate than several preceding experi- mentalists, having, in no one subject, been able to continue their observa- tions for a longer period than forty -five minutes." The report is ably drawn up by Dr. Clendinning.
1 The committee observed that heavier pressure caused " a loud bellows or rasp-sound" (Exp. 7). The same occurred in my Obs. 14.
2 The committee say " at each systole, while the heart acted vigorously, the ventricles i'elt to the finger as hard as cartilage" Again, "The ten- sion and hardness of the ventricles during their systole were very remark- able." (Exp. 14).
3 The committee here say " A first sound was heard, prolonged by a whizzing murmur" (Exp. 9 and 12). Again, "The inversion of the auricles was accompanied with a sensation of thrilling in the finger of the operator, synchronous with the impulse" (Exp. 10 and 12). The murmur and thrill, I had noticed a year previously (See Obs. 26, in the third Series). Also, " On inverting the auricles again, the chordae tendineae of the mitral valve alone, were felt to become tense in systole, and lax in diastole" (Committee Exp. 12). This observation militates against the experimenters' own theory: viz. that the first sound is purely muscular and independent of ex- tension of the valves and their chordae. Again, " The finger being intro- duced into the left ventricle by inversion of the auricle, was felt to be gently embraced and pushed, as if by a membrane distended with blood. On the right side, nothing similar was unequivocally observed" Exp. 14. This ob- servation also, by showing the tense state of the membrane of the valve, opposes the theory of the experimenters.
EXPERIMENTAL RESEARCHES. 55
8. The sound continued, though the right auricle was com- pletely cut open.
9. And, finally, though the finger was introduced into the left ventricle, and was made by pressure to prevent the influx of blood into the right ;
a. Its character, however, was not so clear and smart as when the ventricles contracted on their blood ; 1
b. Thirty or more contractions, the majority very vigorous, took place after the incision had been made. 2
SERIES II.3
Obs. 10. Before the pericardium was opened, both sounds were very distinctly heard.
11. Both were also distinctly heard through the lung interposed between the heart and the end of the stethoscope.4
12. About two or three inches up the aorta from its origin, the second sound was heard (but not the first), alternating with the impulse as felt on the ventricles. (This observation was suggested by myself (not by Mr. Kcate), in consequence of my having pre- viously noticed the same in the living subject, as stated at p. 49).
13. The second sound was decidedly more distinct over the origins of the aorta and pulmonary artery than on the body of the ventricles; and, in that situation, it was louder than the first sound at the same point. It had exactly its natural short, clear, flapping character.
14. The aorta and pulmonary artery being compressed between the fingers, the first sound was accompanied with a loud murmur, and the second was stopped.
15. A common dissecting hook was passed into the pulmonary artery, so as to prevent the closure of the semilunar valves : the second sound was impaired, and a hissing murmur accompanied it. A hook was passed into the aorta, so as to act in the same way on the aortic valves: the second sound entirely ceased, and was replaced by a prolonged hissing. (Heard by several.)
16. When the hooks were withdrawn, the second sound returned and the hissing ceased.
17. Experiment 15 was repeated, and whilst Dr. Hope listened,
1 The committee say "The first sound was still distinctly heard by all, but weak" (Exp. 7).
2 I had made incisions in all my previous experiments, both in 1S30, 1831 and 1834. The idea, therefore, though not specified in the propositions, cannot be claimed by one who had attended those experiments.
3 Present Drs. Williams and Macleod, and Messrs. Keate, Partridge, Malton, Goode, Seagrim, and others who looked in only temporarily— in- cluding Mr. Henry Johnson. Mr. Tatum was absent. The heart acted vigorously for an hour.
4 I made this observation to refute the contrary opinion heLd by M. Ma jendk'.
56 HOPE ON DISEASES OF THE HEART.
the hook was first withdrawn by Dr. Williams from the aorta. Dr. Hope immediately said, "I hear the second sound."
IS. Dr. Williams then removed that from the pulmonary artery; Dr. Hope said, " the second sound is stronger, and the murmur has ceased." (Several listened to 16, 17, and 18.)
19. The arteries were cut open: the heart continuing to con- tract (about eight or ten times), the first sound only was obscurely audible. '
SERIES III.
On August 7th, 1S35, six months after the two preceding series, I performed the following, at the Kinnerton-street Theatre, assisted by Dr. Latham, physician to St. Bartholomew's, Dr. Wntson and Mr. Mayo, physician and surgeon to the Middlesex Hospital, and Mr. Thorpe, a student of St. George's Hospital. My principal ob- ject was to ascertain, with more precision, to what extent the auri- cular valves were subservient to the production of the first sound, and I had projected a new experiment (see below, Obs. 26) with this design.
A large ass, aged 8 or 9, with a pulse at 40, was employed. Having formerly found six or eight grains of woorara barely suf- ficient to kill an animal, and generally in not less than half an hour, and having only two grains of the poison remaining, I adopted the following process, which was singularly successful, the heart having acted no less than two hours after the death of the animal, which is an hour longer than in any other experiment with which I am acquainted, except those of the Dublin Committee of the British Association, performed about the same time, August 1835. " The period," they say, "varied in diiferent subjects from one to two hours.
The jugular vein having been denuded by Mr. Mayo at the ordi- nary bleeding point, which is the most superficial part of the vein, and the finger having been passed round it, a small incision was made in the vessel, just sufficient to admit an ounce syringe charged with a solution of the two grains of woorara in an ounce of water. This being injected, the aperture was pinched up with the forceps and secured by ligature. Respiration instantly began to fail, in less than a minute it had nearly ceased, and in a minute,
1 The committee say " The pulmonary artery being cut across, the first sound was still loud: and the aorta being then cut across likewise, the same result was obtained — viz. a first, without a second sound. The heart was then severed from its several attachments, and the systolic sound was still heard distinctly. The heart was then grasped strongly under blood : it con- tinued to contract vigorously, and the first sound was heard (but not loud) wiih the flexible tube as well as the common stethoscope. The heart was then taken out and held in the hand of one of the committee : when the first sound was distinct, but feeble. On opening the right ventricle, the columnae carneae were distinctly seen contracting simultaneously with the ventricle" (Exp. 14).
EXPERIMENTAL RESEARCHES. 57
wholly. The trachea was then opened, a bellows pipe introduced, and artificial respiration established. The chest was next opened by sawing through the ribs (which were ossified) close to the sternum, and making two incisions along the intercostal spaces to- wards the spine, so as to include three or four ribs, which were then broken backwards. Large vessels were secured in the course of the operation to prevent hemorrhage, because, by taking off' the tension of the vascular system, it diminishes the loudness of the sounds.
The heart, when denuded, was beating steadily and with sur- prising power, about sixty per minute, and it continued to beat between forty and seventy per minute for two hours, the frequency increasing above sixty, whenever, from diminishing the inflation or from compressing the lungs with the hand, the supply of blood to the left side of the heart was insufficient, which was indicated by the flabbiness and diminished size of the left ventricle.
The results (which I have numbered consecutively with the two preceding series) were as follows: —
Obs. 20. The first sound is audible through interposed lung.
21. Tiie second sound is loudest over the sigmoid valves, and for two or three inches along the aorta and pulmonary artery.
22. The first sound is loudest over the parts of the ventricles nearest to the auricular valves.
Having in my written Propositions for the present series re- quested the experimenters to " make observations on the shock of the ventricles at their maximum tension/7 the following' was the answer : —
23. The impulse from lateral expansion was greatest at the mar- gins of the auricular orifices, there throwing the finger out with a violent jerk. The lateral expansion of the base (i. e. upper part) of the ventricles attended the retraction of the apex.
24. On lightly placing the finger and thumb on each side of the pulmonary artery, opposite to the valves, a shock corresponding with the closure of the valves was distinctly and repeatedly felt by Dr. Latham, Mr. Mayo, and myself (Dr. Watson having retired); and I felt the same on applying my finger to the aortic valves.
The same observation was made, a year later, by the London Committee of the British Association, but they had the priority of publication in their Report, August 1836. Their words are, "Immediately after the systole, a flapping or jerking sensation was sensible to the finger applied to the arteries at their roots" (Exp. 10). Again, "on touching the arteries in the vicinity of the valves, a sensation of flapping (or jerking) was observed by all, commencing immediately after the systole, and accompanying the second sound" (Exp. 13).
This observation proves nothing, but it corroborates others by conveying to the mind a strong feeling or impression of the force and smartness with which the semilunar valves close, and of the
58 HOPE ON DISEASES OF THE HEART.
sufficiency of such membranes, so closed, to produce such a sound as the second.
25. A hook was passed into the pulmonary artery and the valves held open. This created a sighing murmur instead of the second sound, previously very distinct. The hook being withdrawn, the murmur ceased and the second sound returned as distinct as before. This was repeated three times with the same result.
On the last occasion the hook got entangled, and on withdrawing it, the sighing murmur, with diminution of the second sound, con- tinued permanent ; which I predicted to indicate an injury of the valve, as was subsequently found to be the case ;
This valve being injured, and about an hour having elapsed, I did not venture to hook up the aortic valves, lest I should be pre- vented from making the next observation (No. 26), which was the main object of the experiment, and from which I hoped for im- portant results. On formerly trying my Proposition No. 5, viz. " push the knuckle or the auricle into each auriculo-ventricular orifice, so as to prevent the expansion of the valves, and see whether this annihilates the first sound," I had found, in Series I. and II., that pushing so large a body as the auricle into the orifice, pre- vented the influx of blood, and thus disturbed the regularity and completeness of the heart's contractions : I therefore devised the fol- lowing mode of accomplishing the same object.
26. I passed a needle of flexible wire through the insertion of the left auricle, and out at the opposite side, and then bent the needle into the ventricle, so as to prevent the sudden expansion and closure of the mitral valve.
This greatly diminished the first sound and created a very loud murmur from regurgitation, which I also felt to be attended with a strong thrill (fremissement cataire) at the margin of the auricular orifice.
Hence the loudness of the first sound is connected with the closure of the valves, but this experiment does not prove that the valves are the sole cause of the sound, because the regurgitation would diminish the tension of the muscular walls and, consequently, the sound produced by it. We occupied an hour in making this single observation, trying it in every way and with the utmost care ; when the action of the heart suddenly and spontaneously stopped, and put an end to the experiment.
Autopsy. — One of the pulmonic valves presented an oval aper- ture from laceration by the hook, capable of admitting a large quill, thus realising my anticipation that this was the cause of Ihe per- manent murmur from regurgitation.
An interesting appearance was noticed along the margins of the aperture and at several points of the pulmonary artery and interior of the ventricle, where the lining membrane had been lacerated by the point of the hook: namely, the parts were overspread with a
EXPERIMENTAL RESEARCHES. 59
number of pink, semitransparent, fibrinous coagula, the size of pins' heads, and easily removable with the handle of the scalpel. Their characters, in short, were closely analogous to those of ordinary valvular vegetations. It may be a question whether they proceeded from inflammatory exudation of lymph, or from mere entanglement of blood by the broken surface. The former view is perhaps the more probable.
[Report of Experiments on ike Action of the Heart, by C. W. Pennock and E. M. Moore.
Impressed with the importance of the experiments to illustrate the heart's action, instituted a few years since by some European physiologists, we had resolved, more than a year past, to repeat them upon the first favourable op- portunity. We were the more anxious to perform them, as the subject is one that has received but little attention in this country, and the profession seems scarcely aware of its importance. Circumstances, however, prevent- ed us from carrying our designs into effect until a short time since; when upon application to an intelligent victualler in a neighbouring village, every facility was afforded us. We have been assisted by several medical gentle- men ; but to Dr. Hardy, of the Philadelphia Hospital, who aided us in all the experiments, may be mainly attributed their successful results. We were also kindly assisted by Dr. Wood, Resident Physician of Frankford Asylum, Dr. Stille, of Pennsylvania Hospital, and Mr. Burns, of Mobile.
Before proceeding to detail the experiments, we may say that the stethos- copes or ear-trumpets used were flexible, constructed of a coil of wire, covered with gum elastic and silk; one, about four feet long, the ear-piece and hollow cone for the reception of sound, being of horn ; the other, about two feet long, the ends composed of biock- tin, and smaller than the first. This instrument is essential to the success of the experiment, as the impulse is so great with the ordinary stethoscope, as to render the analysis of sound very uncertain. In measuring the heart, the ordinary shoemaker's measure is used, by which very accurate results may be obtained. Artificial respira- tion was maintained by the bellows, at eighteen to twenty inflations of the lungs per minute.
Experiment 1st. — Present, Drs. Hardy, Wood, Pennock and Moore.
A ram about one year old was selected.
Owing to the alarm of the animal, it was found extremely difficult to ascertain the natural pulse and respiration; but during the time he was most quiet, the former ranged from ninety-six to one hundred ar.d eight per minute, and the latter from thirty to forty in the same time. The stethos- cope, applied to the left side of the chest, opposite the fourth rib, revealed the sounds of the heart distinct and normal, but faint. Upon the sternum, in the same line they could scarcely be distinguished. The animal was then deprived of sensation by several blows upon the anterior portion cf the cranium; and the bellows-tube being immediately introduced through an incision of the trachea, respiration was artificially sustained. An incision was then made down upon the sternum, and extending its whole length, with a knife whose edge was purposely roughened to prevent haemorrhage. The bone was then divided longitudinally by a saw, and its parts separated by hooks, thus presenting a cavity of six or eight inches in diameter. Ten minutes had elapsed from the time the blow was given until the chest was opened, but the heart was still observed to bent irregularly and very rapidly. The excitement, however, soon subsided, and the heart pulsated regularly, and with a frequency of ninety-six per minute. The stethoscope was first applied to the heart — the pericaidium being still unopened — and the sounds were observed to be of the same character as previously observed, but much louder. The first sound appeared to occupy about one half of the whole
60 HOPE ON DISEASES OF THE HEART.
time of a pulsation; this was followed by the second which is about one half as' long as the first, or one fourth of the whole, and is more flapping than the first ; the remaining time is occupied by repose.
The head of the auscultator being averted, and his eyes closed, the end of the stethoscope "was applied by an assistant to the base near the valves, and to the body of the heart alternately; and it was decided by each in succession, that the first sound was louder over the body of the ventricles than near the valves, while the second sound was much more distinct near the valves, than over the ventricles elsewhere. The change, however, modified the second sound much more than the first. A portion of the lungs being interposed, we found the sounds duller, but in other respects of the same character. The anterior portion of the pericardium was then remov- ed, and the heart exposed, presenting the right ventricle and auricle, and a small portion of the left ventricle, the auricle being concealed behind the heart. During the ventricular systole, the right ventricle was observed to be flattened, and the finger and stethoscope being applied, the first sound and impulse occurred at the same time. During this contraction the base of the heart revolved for a short distance to the left, supposed to be about one six- teenth of a circle, while the apex turned to the right at the same moment, thus causing the heart to assume a spiral form during the systole. The transverse diameter was much diminished by this systole; during diastole it increased, and the heart assumed a rounded appearance. The stethoscope was again applied in the same manner as heretofore detailed, and with the same result. A comparison being instituted, with the head averted as be- fore, between the character of the sounds over the right and left ventricle, it was unanimously conceded, that on the right, the first sound was flapping and shorter than on the left, while on the latter it was prolonged and rush- ing. The first sound, impulse, and ventricular systole, were synchronous. There was, however, an appreciable difference between the contraction of the ventricles, and the pulse, increasing as the distance from the heart was greater. The pulse varied from eighty-four to ninety-six, becoming irregu- lar when the artificial respiration was omitted or too rapid.
The heart pulsated two hours after opening of the chest.
Experiment 2d. — Present, Drs. Hardy, Pennock and Moore. A ram, about a year old, whose pulse was irregular, but seventy-eight per minute, was selected lor the experiment, on account of the slowness of the heart's pulsation, which facilitates the analysis both of the sounds and motion. Sen- sation was destroyed by blows upon the head, as in the preceding experi- ment, and the chest opened as before, but the heart beat feebly and irregu- larly, being congested, and expelling but a small portion of its contents. The sounds were feeble over the right ventricle, (not observed over the left,) and the second soon disappeared entirely; but the first sound remained, whilst the heart contracted, which ceased to beat in a short time.
Experiment 3d— -Present, Drs. Hardy, Pennock and Moore. A ram, six months old, was chosen; pulse, 102; respiration, 32. Was struck upon the forehead anterior to the horns. Some difficulty was experienced in intro- ducing the tube connected with the bellows, and in opening the chest. Fif- teen minutes elapsed before the heart was exposed. It was found congested and its action irregular. The sounds were more feeble, and the heart con- tracted less forcibly than in the first experiment, but the coincidence be- tween the impulse and the ventricular systole were the same, as were also the spiral motion, the peculiar character and succession of the sounds, as well as their comparative intensity at the base and body of the heart. Sus- pecting from the experiments of others, as- well as from the facts we had observed, that the semilunar valves were concerned in the production of the second sound, we attempted to elevate them by hooks introduced into the aorta and pulmonary artery, and note the effect upon the sounds. In co'nse- quence of puncturing the artery, hemorrhage succeeded, and we failed in our purpose. The heart, while still beating, was removed from the body,
EXPERIMENTAL RESEARCHES. 61
and the stethoscope applied to the ventricle. It continued to contract many- times while in the hand, and during contraction, a sound resembling the first sound was heard, differing only in being more feeble. But one sound was heard. The ventricles were then slit open longitudinally, and emptied of blood, and the same sound was elicited. Pulse lell at one time to 84 per minute. Heart beat three fourths of an hour.
Experiment Ath.— Present, Drs. Hardy, Pennock and Moore. A ram, about a year old, was opened as in experiment 3d. Our attention was now directed exclusively to raising the semilunar valves, but without success. The heart was again removed as -in former experiment, the ventricle and right auricle cut open, and emptied of blood, and the fingers thrust into the apertures, thus elevating the tricuspid and semilunar valves. A sound pre- cisely similar to that in the last experiment was detected, but less intense.
Experiment 5th. — Present, Drs. Hardy, Wood and Moore. A ram, about a year old. We administered two drachms of Allen's Prussic Acid, contain- ing ten drops of the pure acid. Spasmodic breathing was induced in a few seconds. At the expiration of one minute and a half, the trachea was opened ; and respiration established at the end of two minutes. Immediately upon cutting through the integuments, no blood was observed to flow. At the end of four minutes, the heart was exposed, but perfectly motionless and enor- mously distended.
Experiment ^th. — Present, Drs. Hardy, Pennock, Moore and Mr. Burns. The animal, an ewe, one year old. Deprived of sensation as before. Opened in fifteen minutes. Heart contracted irregularly at first. Same character of first and second sound; same relation of pulse, impulse and ventricular contraction, and same comparative character of sounds upon the left and right ventricles as in first experiment. Heart did not contract vigorously as in first experiment, and when the right ventricles became congested, the second sound disappeared over it. The contractions of the two ventricles were also synchronous. The heart being allowed to rest upon the collapsed lungs, the apex was not observed to rise. The heart during the contraction of the ventricle diminishes transversely, but elongates about one fourth of an inch, as measured from base to apex. We again failed in elevating the valves. The heart was removed as in experiments 3d and 4th, with the same results.
Experiment 7th. — As those experimenters who had preceded us had found greater success upon the calf, we procured one about nine days old. It was deprived of sensation by a blow upon the occiput. Some difficulty was ex- perienced in opening the trachea, and two minutes had elapsed before arti- ficial respiration was commenced ; and upon opening the chest, life was extinct ; a few very feeble contractions being observed in the right ventricle.
Experiment Slh.— A calf, five days old, pulse one hundred and thirty ; respiration, thirty-two. Both sounds heard distinctly through the chest. The animal was struck upon the forehead, immediately above the frontal sinus. The chest opened as in first experiment. Same spiral motion ob- served during contraction. The elongation at the same time one fourth of an inch, as measured from union of aorta and ventricle to the apex. The whole heart has an apparent motion from the base towards the apex, and the pulmonary artery turns partially around the aorta, which is a fixed point, describing about thj arc previously mentioned. The same flattening of right ventricle during its contraction as before observed. When the stethoscope was placed upon the aorta, two inches above the valves, both sounds were heard, but the second sound much louder than the first. Over the pulmonary artery both sounds were faint, but especially the second, which disappeared as the heart became feeble. A curved needle was passed into the aorta, but the sounds were indistinct, and the second appeared to be absent sometimes, and not at others, when the hook was in the artery. Upon examination after the removal of the heart, it was found that the valves were sometimes elevated, and at others not.
62 HOPE ON DISEASES OF THE HEART.
Experiment 9th. — Experiencing great difficulty in analysing some of the movements and sounds of the heart in animals of the size upon which we had experimented, we resolved to inspect the heart of a horse, in which the pulse in health ranges from thirty to forty per minute. In this experiment we were assisted by Drs. Gerhard, Stewardson, Peace, Hardy, Fell and Goddard, but to the latter gentleman, especially, we owe our thanks for the assistance rendered.
We found in the animal we had selected that the pulse was about thirty- six per minute, and respiration twenty-eight in the same time.
In order to prolong life, the trachea was opened before the blow was given. Immediately after the blow was struck, which was directed to the forehead, that the skull might be depressed upon the anterior lobes of the brain, the bellows-tube was introduced, and artificial respiration commenced. The skin was dissected back from the median line upon the thorax, the cartilages of the ribs sawn through upon the left side of the sternum, and several of the ribs cut off about one third of their whole length from their sternal ex- tremity. On account of the hemorrhage, we were obliged to secure many arteries, and twenty-five minutes had elapsed from the time the blow was given until the heart was exposed. It presented the left ventricle, the ap- pendix of the left auricle and a portion of the right ventricle. The pulsa- tions were one hundred per minute, but on account of its size we were enabled to observe the relative contraction of the auricle and ventricle, which we found to succeed each other as follows : — During the contraction of the ventricle, the auricle dilates; at the expiration of the systole, the auricle contracts, and the diastole of the ventricle commences, the auricular con- traction apparently occupying about one half the time of the ventricular diastole. During its systole, the left ventricle flattens and elongates. During its diastole it shortens, and assumes a rounded form. The sounds were detected, but not loud; the second not existing over the pulmonary artery, but heard over the body of the left ventricle.
Death arrested the further progress of the experiment, twenty minutes after the chest was opened. * * *
Although every experiment had confirmed our views of the agency of the valves of the aorta in the production of the second sound, we had heretofore failed in elevating them ; we were also still doubtful respecting the relative contraction of the auricle and ventricle, for, although the last experiment had appeared more satisfactory on this point than several of the preceding, yet, as life continued but a short time after opening the thorax, and as many circumstances unfavourable to clear and calm observation were connected with the experiment, we resolved to pursue the investigation of these obscure points, and to exhibit the facts that we had observed to a few medical friends.
Experiment 10th. — Present, Drs. Gerhard, Goddard, Stewardson, Peace, Hardy, Pennock and Moore. A ram, about six months old. Pulse, ninety- six. Deprived of sensation by a blow upon the head, and opened as in ex- periment 1st. The heart contracted well, but exhibited great irritability when touched. Its pulsations rose to one hundred and fifty per minute, ren- dering it difficult to analyse the sounds; but the first sound and impulse were observed to coincide. The spiral motion and elongation were as here- tofore detailed. While still contracting forcibly, the heart was removed from the body, and the first sound heard when entire, and also when both ventricles Avere cut open and emptied of blood.
Experiment llth. — As the last experiment had not been very satisfactory, the same gentlemen being present, we pursued the investigation upon a calf, four weeks old. Pulse, one hundred and five. Both sounds distinctly heard through the chest. Struck upon anterior portion of the cranium, and opened as before. The pericardium was left entire, to avoid the irritation of imme- diate contact with the heart. The stethoscope was placed alternately upon the aorta, the body of the right ventricle, and upon the septum, near the
EXPERIMENTAL RESEARCHES. 63
apex. Upon the aorta the second sound was found to predominate ; upon the body of the right ventricle it was scarcely heard, and the first was pre- sent ; and near the apex upon the left ventricle, or septum, both were detected; the first, louder. The spiral motion, the elongation, and elevation of the apex as before observed. A hook was passed into the aorta by Dr. Moore, and one of the semi-lunar valves elevated ; the eyes of the auscultator were closed, to prevent the possibility of bias from preconceived opinions. While in this position, the auscultator announced the absence of the second sound, and the accession of a rough bellows sound in the first sound. The hook was then withdrawn, and the second sound was declared to have returned. This experiment was tried twice by each, and by some three times in suc- cession, and the results were uniform. No hook was passed into the pulmo- nary artery, inasmuch as no sound was heard over it at this time. The auricle contracted while in the hand, emptied of blood.
Experiment \2th. — A ram, six months old. Present Drs. Stille, Hardy, Pennock and Moore. Pulse, ninety-six; respiration fifty-six. Animal struck upon forehead, as in the previous experiments, and artificial respiration established in three fourths of a minute. During the opening of the chest, much hemorrhage took place. The heart was at first tumultuous in its action, but became regular in a few minutes. The first and second sound were heard over the body of the right ventricle, but more feebly than over the left; both sounds were heard over the left ventricle and aorta, but the second louder than the first over the latter than over the former. Hooks were passed into the ventricle, for the purpose of keeping open the auriculo- ventricular valves. (These, however, failed of effecting the object, as seen upon examination afterwards.) The sounds gradually became more feeble as the heart congested, and the second sound ceased altogether, both over the heart and arteries, while the first still remained. The auricle was ob- served to contract over its entire surface, as much upon the body as upon the appendix. The contractions with reference to the ventricles were irregular at this time, except for a very short period, when they appeared to precede those of the ventricle immediately, recurring at the termination of repose. The heart contracted one hour after the blow was given.
Experiment V3th. — Wether, nine months old. This experiment failed on account of defect in the apparatus for maintaining respiration. As the heart became more feeble, the auricle appeared to contract immediately antecedent to the systole of the ventricle, but owing to the circumstances attendant upon this experiment, we feel very uncertain as regards tire observation. . Experiment lAth. — Ewe, nine months old. Struck as before. Trachea opened in half a minute. Chest opened in four minutes. Heart tumultu- ous. It gradually became more quiet, until it fell to one hundred and twenty, and contracted forcibly. The first sound alone wras heard over the right ventricle and pulmonary artery. Pressure upon this artery produced a bel- lows sound in the first sound. The auricles were pushed into the auriculo- ventricular openings by the fingers. The first sound was thus rendered much more feeble, and lost its sharp character; the ventricles contracting imperfectly and irregularly.
Experiment ihth. — A calf, five days old, pulse, one hundred and twenty- six ; respiration 30. Sensation destroyed by a blow upon the head, as before. Artificial respiration established in two minutes and a half. The heart was exposed in six minutes, rather hurried in its action, but soon fell to one hun- dred and twenty pulsations per minute. The heart contracted with a moderate force. The second sound extremely feeble over the body of the right ventricle and pulmonary artery ; but it soon disappeared over both. The sound was still heard over the left ventricle and aorta, louder over the latter. The auricle contracted with a quick motion, the contraction not being confined to the appendix, but extending over the whole body of the organ. As the heart became weaker, the pulsations were slower, and we were enabled to analyse the relative contractions of the auricle and ventricle
64 HOPE ON DISEASES OP THE HEART.
much better than at any previous experiment. They evidently bore a dif- ferent relation from what we had previously supposed. The succession is as follows: — First the auricle contracts, and the action is immediately pro- pagated to the ventricle, which contracts, instantly, accompanied with the diastole of the auricle ; the diastole of the ventricle immediately follows, accompanied with a subsidence of the auricle by passive and not active con- traction, which partially fills the ventricle; then follows the state of repose, at the termination of which, the auricle contracts. During the dilatation of the auricle, the vena cava also dilates, but it Was difficult to say, whether the cava dilated during the contraction of the auricle or not, as the con- traction of the latter was so rapid and so soon followed by the contraction of the ventricle. While still contracting, and when scarcely any sound was heard upon the ventricles, the stethoscope was applied to each auricle, and a sound similar to the first was heard, but very short, and more flapping, resembling very nearly the first sound of the foetal heart.
Experiment 16th. — A calf, two months old. Pulse ninety. Deprived of sensation as before. The chest was opened in eight minutes, and a i"ew ribs removed from the left side. The heart pulsated slowly, and at a rate of ninety -five per minute ; both sounds were distinct, but not loud. The second sound was heard more loudly over the pulmonary artery than on the right ventricle, the sound being but feeble in either position. Both sounds were heard upon the left ventricle. An instrument was introduced into the left ventricle, through the auricle, and the mitral valves prevented from col- lapsing; this produced congestion of the ventricle immediately, and the action became hurried and irregular. The stethoscope being applied to the left ventricle, the sound was not as loud and clear as before, but not modi- fied in any other manner. The instrument was then withdrawn, and the sound became loader. The relative contractions of the auricles and ventri- cles were as in the last experiment.
The difference in the intensity of the first sound in this experiment, when the mitral valve was kept open and when allowed to close, may be attri- buted to the fact that there was no fixed point for the muscle of the ventri- cle to act upon, by the retention of the blood, and it therefore could not empty itself of its contents, and, of course, would not yield a strong sound.
From the preceding experiments we draw the following conclusions:
1st. The pulse is synchronous with, and caused by, the ventricular con- traction,— and when felt externally, arises from the striking of the apex of the heart against the thorax.
2d. The expulsion of the blood from the ventricles is effected by an ap- proximation of the sides of the heart only, and not by a contraction of the apex towards the base; during the systole the heart performs a spiral move- ment, and becomes elongated. (Experiments 6th, 10th, and 11th.) ■
3d. The ventricle contracts and the auricle dilates at the same time, occupying about one half of the whole time required for contraction, diastole, and repose. Immediately at the termination of the systole of the ventricle, its diastole succeeds, occupying about one fourth of the whole time, syn- chronous with which the auricle diminishes, by emptying a portion of its blood in the ventricle, unaccompanied with muscular contraction. The re- maining fourth is devoted to the repose of the ventricles, near the termina- tion of which the auricle contracts actively, with a short, quick motion, thus distending the ventricles with an additional quantity of blood: this motion is propagated immediately to the ventricles, and thfir systole takes place, rendering their contractions almost continuous. (Experiments 15 and 16.)
4th. From the termination of their diastole to the commencement of their systole, the ventricles are in a state of perfect repose, their cavities remain- ing full, but not distended, while those of the auricles are partially so, during the whole time.
5th. The sounds are produced by the motions of the heart or its contents, and not by striking against the thorax, as proved in all the experiments;
EXPERIMENTAL RESEARCHES. 65
being much louder when the stethoscope was applied directly to the heart, than when to the chest, or with the lungs interposed.
6th. The sounds are more distinct when the muscle is thin, and contracts quickly. Hence, the clear, flapping character of the first sound over the right ventricle, as compared with the left.
7th. The first sound, the impulse, and the ventricular systole, are synchro- nous. This sound may be a combination of that caused by the contraction of the auricles, the flapping of the auriculo-ventricular valves, the rush of blood from the ventricles, and the sound of muscular contraction. From experiments 3d, 4th, 6th, and 10th, when the heart was removed from the body, the ventricles cut open and emptied of their contents, the auriculo- ventricular valves elevated, and a sound, resembling the first, still heard, it may be chiefly attributed to the muscular contraction. That these valves aid but slightly in its production, may also be inferred from Experiment 16.
8th. The second sound is caused exclusively by the closure of the semi- lunar valves from the reaction of the arterial columns of blood upon them, in its tendency to regurgitate through the aortic and pulmonary orifices. This is proved by the greater intensity of this sound over the aorta than elsewhere, the blood having a strong tendency to return through the valvu- lar opening ; by the greater feebleness of the sound over the pulmonary artery, which is short, and soon distributes its blood through the lungs, thus producing but slight impulse upon the valves in the attempt to regurgitate; by the disappearance of the sound, when the heart becomes congested and contracts feebly; and, finally, on account of its entire extinction when the valve of the aorta was elevated.
9th. The second sound is synchronous with the diastole of the ventricle.
From these experiments, it will be seen that our conclusions coincide very nearly with those of the British physiologists, — the correctness of whose results, when compared with those of the French, may be mainly attributed to the use of larger animals. From our observations, calves, of from four to eight weeks old, are decidedly preferable to other quadrupeds for these investigations. The tenacity of life of calves of this age is greater than in older animals, whilst the cardiac pulsations are slower, and more forcible, than they are in the younger. The heart of this animal, too, is of large size, and the introduction of hooks for the elevation of the valves is readily effected.
The English and Irish physiologists enjoyed great facilities in the slow and regular action of the heart, as induced by the woorara. Perhaps, at some future period, when this may be obtained, the investigations may be pursued, as other points of enquiry are offered.
C. W. Pennock, E. M. Moore.
Philadelphia, Nov. 2, 1839.
Experiments on the Motions and Sounds of the Heart, By the London Committees of the British Association for 1838-39 and 1839-40.
Experiments for 1839-40. In consequence of having been appointed to conduct the experiments on the motions and sounds of the heart for the current year, without being asso- ciated with any colleagues, I thought it desirable to avail myself of the as- sistance of such of my friends, including the other members of last year's committee, as could attend, and I accordingly requested the co-operation of a considerable number of gentlemen known to the public. Of ihese, several were able to attend on numerous occasions, and one of them, Dr. Boyd, Resident Physician of the St. Marylebone Infirmary, on every occasion, so that every observation and experiment has been witnessed by one, or in most instances several, of the following gentlemen; to several of whom I am indebted for very important assistance: —
8 — g 5 hope
66 HOPE ON DISEASES OF THE HEART.
Professor C. J. B. Williams; George Gulliver, Esq., F. R. S; John George Perry, Esq.; Dr. G. Hamilton Roe; Dr. George Burrows; Charles Cochrane, Esq.; Dr. Rutherford; Francis Kiernan, Esq., F. R. S. ; J. Sid- dell, Esq.; T. K. Pritchard, Esq.} Francis Samwell, Esq.; Dr. Edwin Harrison; R. A. Stafford, Esq.; Benjamin Phillips, Esq,, F. R. S.; Dr. Robert Boyd, and other gentlemen, private friends of the Reporter, and the last four named gentlemen, his colleagues in the staff of the St. Marylebone iDfirmary.
The experiments were performed in a convenient locality immediately adjoining the St. Marylebone Infirmary, and principally on donkey colts of a few months old. In the latter part of the series other animals, and espe- cially dogs, were used, partly for economy and in order that the limited pe- cuniary resources at my command might not be prematurely exhausted ; and partly because certain experiments contemplated were expected to prove more easily and decisively practicable on the larger heart of the ass, than on any smaller, such as that of the dog: and that in any event it was desirable to extend the range of observation as far as practicable over the animal scale.
The mode of preparation was in all cases nearly the same. In almost every case, sensibility was withdrawn as completely as was practicable, by one method or other. In donkeys, I availed myself of the stupefying pro- perty of the woorara poison, for a packet of which I had been indebted since 1838 to Sir B. C. Brodie. The woorara was brought into operation by in- jecting a couple of grains of it, partly dissolved, partly suspended in water, into the external jugular vein, as practised by Mr. Mayo in an experiment of Dr. Hope's, and the injection was usually fojlbwed in a very few minutes, by complete insensibility. In smaller animals prussic acid was used in several instances, and in a few the subject was stunned by a blow on the head. Artificial breathing was used in every warm-blooded subject, by means of a bellows and long flexible tube kept loose in the trachea; the chest was opened, nearly as directed by Galen (de admin, anat.), and as practised by former committees, and five or six ribs, at least, were separated from the sternum, and broken near the articulation, and bent back over the vertebrae. In every case, whether during the preparation or subsequent ob- servation, all convenient means were used, as advised by Galen, to prevent or lessen hemorrhage, in order to avoid, as much as possible, the anomalous modes of action attending extreme vascular depletion, and to prolong the op- portunities of observation and experiment.
The observations about to be detailed consist partly of experiments in continuation of the inquiries of former commitiees, and partly of experiments conceived and performed with a view to decide several points in dispute amongst physiologists of authority, which were not investigated, by those committees, and which seemed to me yet unsettled, and at the same time important enough to call for direct experimental investigation. The follow- ing are the principal of those undecided questions.
1. With respect to the rhy thm of ihe motions of the auricles and ventricles, several living distinguished physiological writers appear to hold, that those cavities act in strict alternation with each other, and not continuously or in immediate succession, the auricles being first in systole and diastole, and the ventricular actions being last before the Rest, as described by Steno, Har- vey, Lancisi, Haller, Senac, &c. ; and by Hope, Williams, Carlile, Pen- nock and Moore, and other distinguished living experimentalists.
2. With respect to the share in the circulation due to the auricular systole, it has been declared to be active, and of much importance, by Harvey, Senac and others; while several living writers of great weight, adhering apparently to the views of Galen, Vesalius, &c, seem disposed to refuse to the auricles any very influential or positively important share in the cardiac operations; for examples, I may cite Dr. Elliotson, Prof. Bouillaud, Dr. Hope, Sir B. C. Brodie, &c.
3. With respect to the shape and dimensions of the ventricles in systole.
EXPERIMENTAL RESEARCHES. 67
it was held by Galen, Vesalius, Harvey, &c, that the heart is shortened in diastole, and lengthened in systole; but the observations of Steno, Lower, Lancisi, Haller, and others, gave currency to opposite views. Of late, however, the ancient opinion has been received ; for example, by Professor Burdach and Professor Bouillaud, as I understand their observations, and by Drs. Pennock and Moore, the latest experimentalists on the subject that I know of, except my friends and myself.
4. With respect to the precordial impulse, the great majority of physiolo- gists, adhering unqualifiedly to the ancient opinion, advocated by Hippo- crates and Galen, amongst the Greeks, and by Vesalius, Harvey, Lancisi, Senac, Haller, Hunter, &c, ascribe the cardiac pulsation to a blow or stroke (in the popular meaning of those words) given by the heart's apex in systole to the ribs : and refer the apparent inaction in the heart, between its pulsa- tions, to the retreat of the organ during its diastole inwards, and away from the walls of the chest. But in opposition to this view may be cited the ex- periments of several recent observers, and the arguments of Mr. Carlile, of Dr. Hope, (in his last edition,) of Mr. Bryan, of Dr. Billing, &c. dec.
5. With respect to the diastole of the heart, it was held by Galen and Vesalius to include a strong force of suction, by which principally the venous current was forwarded and the auricles were emptied; and this power of inhalation or suction has been adopted by numerous living authorities; e.g. Professor Bouillaud, Dr. Hope and Dr. Copeland ; and has even been ex- tended to the auricular diastole, e. g. by Professor Allison and Dr. Elliotson. The exertion, however, of any such force has been distinctly denied to the diastolic state by Harvey, Lower, Senac, &c; and recently by Dr. Billing and Dr. Arnott, as physical absurdities, and the opinion appears, Dr. Joy remarks, to rest on no satisfactory experimental evidence whatsoever.
6. In addition to active pulsations observed in certain animals in the veins, (as in hares, rabbits, dogs, fowls, frogs, &c.,) there have been noted by several experimentalists, of whom it is sufficient to name the great Haller, certain passive pulsations, viz., an abrupt diastole of the vein attending the first part of the heart's systole, or the auricular contraction, and an abrupt systole of the vein attending the first part of the heart's diastole, or the dila- tation of the auricle ; but the connection between this venous regurgitation and the auricular systole has been doubted by several apparently, and even doubted by Dr. Elliotson.
7. Reverting to the auricular function, the systole of the auricles has usually been regarded as unattended by any intrinsic sound. Dr. Hope de- nies that any such sound occurs, and on physical grounds seems to affirm that it is not possible ; and Dr. Joy calls the auricular systole a " silent" act. (Library of Practical Medicine.) Six months probably, or more, however, before the London commissioner for 1840 had even begun his experiments, Drs. Pennock and Moore had, unknown to him and his friends, detected, as they conceived, an auricular systolic sound in a series of very interesting experiments, of which an account is published in the American Journal of Medical Science, No. 50, February, 1840.
S. The following often agitated and still moot points have appeared to the Reporter in like manner to stand in need of further examination : e. g. 1, the sizes of the cavities, &c, with respect to each other; 2, the produc- tion of sound by certain muscles while vigorously contracting; 3, the rhythm of the cardiac and arterial pulse, &c. &c. Finding on all the preceding points considerable difference of opinion, and perceiving that, in many in- stances,the decisions of highly distinguished and leadingphysiological writers were at variance with what he considered to be the best hitherto recorded experiments and observations, the Reporter found forced on his mind the conviction that on all or most of those points further data were wanting, and experiments less ambiguous, and more pointed and conclusive. Under such impressions the Reporter felt himself at liberty, if not positively called on, to advert to the various questions above alluded to, which had not been
5*
68 HOPE ON DISEASES OP THE HEART.
handled by former committees, provided that by any unlooked for good for- tune, if not through some new and happier experimental combinations, he should 'succeed in eliciting pertinent and decisive facts. Acting on such views, he has put to the test of experiment, to a greater or less extent, several of those questions, with results now to be stated.
It may be proper to mention that the instrument used in auscultation was exclusively the flexible ear-tube ; the wooden stethoscope, inconvenient in most cases, being found quite unsuited for such experiments.
Conclusions from both series of experiments and observations, viz. those of 1838-39, and those of 1839-40.
MOTIONS.
1. That the order of the motions of the auricles and ventricles is by con- tinuous succession rather than by alternation of actions. The auricles con- tract abruptly after the rest or pause, and the ventricles immediately after the auricles, without any distinct interval between the successive systoles; and the diastoles of the cavities follow in somewhat similar order, viz. the auricular diastole coinciding with the ventricular systole, and continuing after ; and the true rest or pause of the heart being constituted by the dias- toles of auricles and ventricles together, and in reality, though not in a man- ner sensible externally, ceasing on the recurrence of the auricular systole: and this rhythm of the motions seems to be universal, and common to warm and cold blooded animals. '
2. That the visible systolic and diastolic motions are first perceived at the bases or fixed parts of the cavities, viz. in the auricles at the sinuses, and in the ventricles at the fundus cordis, and that the apices of the auricles and ventricles, or free parts, are brought into full action after the other parts, and only just before the supervention of the opposite and next succeeding con- dition of the cavities respectively, whether that condition be systole or dias- tole.
3. That in systole the heart is diminished (except only in such regions or parts of the organs as may have been previously compressed or collapsed, during the unresisting flaccidity of the diastole), and then its long axis in particular is strikingly and invariably shortened.2
4. That the normal systolic action of the auricles is energetic and almost instantaneous, and quite universal: the manifestations of contraction in the appendix perceptibly succeeding to those of contraction in the sinus, although by a very minute interval ; and that the normal auricular diastole is gradual, continuous, and wholly passive, and is effected by an influx of blood from the cava progressively distending the cavity from sinus to apex, and from the termination of one systole of the cavity to the commencement of the succeeding one.
5. That the systole of the ventricles is gradual in its developement, and complex in its phenomena; part of these phenomena being attributable to contraction in the muscular parietes, and part to reaction on the part of the fluids. By the muscular contraction the heart is made to compress the
1 The only exception known to the Reporter, from books or observation, seems ap- parent rather than real, viz. an alternation of action, as noted by Lancisi, in the chick in ovo, and by several observers, for example, in cases of very rapid cardiac action. In such cases the diastoles have been so hurried and short (owing-, no doubt, to very rapid and copious influx from the veins,) that the systoles of the ventricles have been closely approximated to each other, and the intervening rest_been apparently suppress- ed, and an apparent alternation of systole and diastole without intervening rest been produced.
2 This statement is diametrically opposed to the observations of Drs. Pennock and Moore. In every experiment on the heart's action, they invariably found that organ was elongated during its systole. As this point is an extremely interesting physiologi- cal problem, it will speedily receive further investigation.
EXPERIMENTAL RESEARCHES. 69
blood, which resists in all directions alike, and thrusts out the previously- flattened, depressed, or collapsed sides of the ventricles, and effectuates in great part that shortening of the organ, that is required to admit of closure of the auri-ventricular valves; and this reaction of the fluids mainly con- tributes under certain favouring circumstances of position, &c, to cause the motion that has been described as tilting of the apex, ccc, which motion is principally, (the Reporter believes exclusively.) a result of the elevation of the long axis of the heart in systole, caused by the assumption of a convex or globular form in the central parts of the organ, instead of the superiorly and inferiorly or laterally compressed state of the previous diastole.
With respect to diastole, it appears that the ventricular diastole or dilata- tion is wholly passive, exerting no influence over the venous current, or the motion of the arterial valves, and is partly effected by an influx of blood from the veins commencing at the moment of relaxation of the ventricles, and continuing until the succeeding systole, and reinforced immediately before the latter by an abrupt influx from the auricles.
6. That the pulsations of the veins are of two kinds, at least in some ani- mals, viz. both active and passive ; and the latter or passive pulsations, which, on the authority of Haller, may be held to exist in all animals, are attributable to reflux from the auricles in their systole.
7. The precordial throb or pulsation is caused, immediately, by the undulation of the blood in its resistance to sudden muscular compression in the systole of the ventricles. This reaction of the fluids is first perceived about the fundus of the ventricles, and last about the apex, towards which it seems to be propagated by a continuous undulation from the fundus with extreme rapidity. In consequence of this reaction of the blood, the heart's sides ate rendered convex, instead of compressed or flattened as in diastole, and are, in the middle parts more especially, heaved outwards from the central axis abruptly and with great force. Thus on all parts of the surface of the organ an impulse is fell in systole, which is greatest there, when, in addition to placid flaccidity of walls, there has been collapse in the diastole (viz. the central parts), and which is least when such collapse has previously been wanting or slight (viz. the apex). This cardiac impulse is usually perceived in the healthy subject, over the apex only, owing to its being absorbed and neutralised over other parts of the heart by an interposed thick mass of spongy lung.
The heart does not oscillate on the aorta, or move to and fro in the chest from systole to diastole, and vice versa; nor does it suffer any changes in consequence of its own efforts, and exclusively of movements of the lungs and diaphragm, excepting in its shape and size, and in the thickness and tension of its parietes, and the capacities of its cavities. The doctrine that the precordial pulsation is caused by a blow received by the ribs, in conse- quence of the heart's "jumping" (ax/ux, Hippocrates,) or striking against them ("pectus ferii," Harvey. — " Costam ictu perculit," Haller, &c. &c.) appears to be superfluous with a view to explanation of phenomena (not- withstanding the ingenious illustrations of the ancient opinion by Senac and Hunter), and to be substantially unfounded in point of fact.
8. That the arterial diastole or pulse, almost every where outside of the pericardium, perceptibly succeeds to the cardiac systole, though near the heart the interval between them is very brief, and, to unpractised observers, difficult to distinguish.
SOUNDS.
9. That the first sound of the heart depends partly, but, in a slight degree, on the abrupt closure and transitory tension of the auri-ventricular valves, which gives to this sound much of its sharp well defined beginning; but that the first sound is mainly attributable to cardiac muscular tension alone, and that its prolonged duration is owing in great part to the progressive character of the full systolic effort from fundus to apex; and that this sound
70 HOPE ON DISEASES OF THE HEART.
is in no degree attributable to any blow or stroke of the heart against the ribs.
10. That the auricular systole is attended by an intrinsic sound resem- bling that of the ventricles, but more short, obtuse, and feeble. This auri- cular systolic sound is often more difficult of detection, even on the naked heart, and with tolerably vigorous action of the auricles, owing to its being, to the inexperienced ear, absorbed in, or masked by, the immediately suc- ceeding and much louder systolic ventricular sound.
11. That the sounds of friction in pericardites may, when well marked and under ordinary circumstances, be expected to be double at least, and they may be not improbably triple or more. In its systole each cavity of the heart moves so as to cause a friction of its attached lamina in one direction against the adjacent lamina of the pericardium; and in its diastole a peri- cardial friction is caused by each cavity in an opposite direction; and as the auricular appendices move to and fro independently of the ventricles, the normal pericardial frictions must be, as direct observation shows them to be, quadruple, or double with the auricles, and double with the ventricles. If, therefore, those frictions were rendered sonorous by the interposition of any rough substances between the rubbing surfaces, (as lymph for example), and supposing the heart's actions sufficiently vigorous, we might, under ordinary circumstances, anticipate with confidence, a duplication of murmurs at least, one systolic and one diastolic. Now this duplication of sounds must be the principal element in the acoustic diagnosis of pericardites, since effused lymph may be of any thickness, consistence, extent, &c. &c. and may be situate on any portion of the heart's surface between its nearest part and its furthest, and may. therefore, cause friction sounds of the most variable seat, depth, and character. But, of course, another physical means of distinction of great importance remains, viz. the comparatively equable diffusion ol the sounds of pericardial friction all around the seat of attrition rather than in any one or exclusive direction.
12. That the sounds of the structurally healthy heart are much liable to modification by deviations from the normal standard in the condition of the fluids, and in the order and force, and equability of action of the carneag columnse, and other contractile parts governing or influencing the action of the valves, and the closure and opening again of the orifices of the ventricles ; and this dependence of the heart's sounds on conditions material or dynamic, wholly excluding structural defect, is so considerable that the second sound may, in the normal heart, for a time be very variously modified, or masked by strange murmurs, or even apparently suppressed, in consequence of hemorrhage, or from the introduction of poison into the veins; and the first cardiac sound, though never wholly wanting during the active existence of the heart, may still, under similar circumstances to those just referred to, present various abnormal features ; may, ex. gr. be as short as the second sound, or be attended or followed by anomalous murmurs, and be otherwise strikingly modified.
13. Other conclusions, more or less satisfactorily deducible, as the Re- porter conceives, from the facts stated, are, that the peculiar sounds occur- ring in pericardites, and attributable to pericardial frictions, are not referable only to vascular turgescence, or to abnormal dryness, &c. of the pericar- dium, but to lymph effused by and adhering to that membrane, or other similar obstacle to the easy and noiseless gliding over each other of the ad- jacent parts of the pericardium.
14. That the ventricles are of equal capacity during life, and that the in- equality usually met with after death, is an illusion, as explained long since by Harvey.
15. That the suction influence upon the venous circulation, attributed to inspiration by various writers, is well founded.
16. That the action of the long muscles, and more especially those of the abdominal parietes, is attended by an intrinsic sound. The notice of this
EXPERIMENTAL RESEARCHES. 71
fact by the Reporter has been rendered necessary in consequence of some attempts at verification, and some criticisms on an experiment of the Lon- don Committee for 1836-37, published in the last edition of Dr. Hope's ex- cellent work on the heart.
17. That the sounds of the heart, like the motions, are governed by the same law in all warm blooded animals hitherto examined, and probably in all kinds whatsoever, viz., that the first sound in all animals is longer and obtuser, and the second sound shorter and sharper; that those sounds are, as in the human heart, respectively systolic and diastolic j that their causa- tion likewise follows the same law as those of man, the first sound being mainly muscular, and the second exclusively valvular; likewise, that there is the same causation and mutual relation of the cardiac and arterial pulsa- tions.
JOHN CLENDINNING, M. D. Oxon. and Edin., Fellow of the Roy. Col. of Physicians, &c. &c.
P.]
CONCLUSIONS FROM THE WHOLE OF THE EXPERIMENTS ON THE SOUNDS.
CONCLUSIONS ON THE FIRST SOUND.
I shall not notice those theories which ascribe the first sound,
1st. To the collision of the particles of the blood against each other and against the walls, in the interior of the heart (formerly- broached by myself, but discarded in 1832).
2d. To the collision of the opposite interior surfaces of the ven- tricles at the conclusion of their systole — both these theories having been sufficiently disproved.
The theory of M. Magendie is. that the first sound is occasioned by the collision of the heart against the ribs during its systole, and the second, by its collision against the sternum during the diastole. This theory is completely refuted, 1st, by my two origi- nal series of experiments on the ass in 1830 (see p. 39), proving that the sounds were perfect when the sternum and ribs were re- moved : 2d, by my foregoing experiments on the sounds, Obs. 11, in. which cc both sounds were distinctly heard through the lung interposed between the heart and the end of the stethoscope5' — an observation which I made specifically to refute M. Magendie, and which was subsequently verified by the London Committee of the British Association : 3d, it is refuted by hydro-pericardium ; as the sounds are perfect though the interposed fluid prevents the heart from impinging against the walls of the chest. This theory, I should have dismissed more summarily, but that I perceive it has been partially admitted by the London Committee of the British Association, and by one of its members in a separate publication. " An extrinsic or subsidiary sound,'' say the committee, "which, in a variety of circumstances, contributes largely to the first sound, arises from the impulse of the heart against the parietes chiefly of
the thorax;" and Dr. W , in his separate publication, says, "I
am disposed to admit that, in violent action of the organ, its more sudden and abrupt strokes against the chest do cause a sound,
72 HOPE ON DISEASES OF THE HEART.
which constitutes the loud termination of the first sound in these cases, and which seems nearer the ear, and more like a knock, than what is heard in the ordinary action of the heart. In common pul- sations, the apex of the organ is drawn upwards and forwards at each systole, and sliding obliquely on the smooth pericardium, does not impel against the ribs with sufficient abruptness to cause sound. But in quicker and more violent pulses, the abruptness of the mo- tion, and the force of the blow against the side of the chest, are such as can scarcely fail to produce sound." (On Diseases of the Chest, p. 178.)
These conclusions are precipitate. They proceed on an assump- tion which is doubtful at least, if not absolutely erroneous : namely, that the heart "impinges upon" (committee), or gives a "blow
against" (Dr. W ) the chest. Now, as has indeed been well
remarked by Mr. Bryan (Lancet, vol. xxix. p. 501), the heart is held in contact with the walls of the chest by a force of fifteen pounds to each square inch : if held in contact, it cannot impinge or strike a blow : it can merely heave the chest, and such heaving, however sudden or powerful, cannot produce sound. The com- mittee rest on the fact that " leaning" to the left or forwards gave additional force to the impulse and loudness to the sound; while inclination of the body, such as to cause the heart to gravitate away from the ribs, diminished at once the "sound and impulse." But in both these positions, the heart is still in contact with the walls of the chest, as is proved to demonstration by the continuance of dulness on percussion^ — impaired indeed by leaning backwards, but increased by leaning forwards. If, therefore, the heart is more decidedly and positively in constant contact with the chest on lean- ing forward, that is precisely the time when the increase of sound observed by the committee ought not to be referable to the organs " impinging" or " striking a blow" against the chest. This argu- ment alone is conclusive against the doctrine in question; but as the committee attaches much weight to the following experiment, it may be desirable to point out its inconclusiveness.
"When a small opening," say they, "was made in the. carti- lages opposite to the heart, the heart during systole was felt, both outside and inside the chest, to press with force against the sternum and cartilages." But here, if air was not admitted, and the heart was kept in contact with the walls by atmospheric pressure, the observation proves nothing to the point ; as it proves, not a blow, but merely " pressure with force against the sternum" — which pres- sure is insufficient to produce sound. But if air was admitted, the observation still proves nothing; as the air, by causing collapse of the lung, created any interval that existed between the heart and the walls of the chest.
But though it is thus proved that the first sound does not receive an augmentation from the heart impinging against the walls of the chest (a conclusion to which I may here