Chapter XLII: Part 42

Acute interstitial myocarditis occurs in connection with the infectious fevers, and also with pericarditis, more rarely endocarditis. It is characterized by the presence of numerous round cells in the interfibrillar tissue, multiplication of the corpuscles, and degeneration, granular or fatty, of the muscle-fibres. The coarse appearances are--a relaxed state of the cardiac walls, pale or turbid condition of substance, in extreme instances a sodden, soft friable state, so that the muscle readily tears on pressure. In acute pericarditis the superficial myocardium, for a line or two beneath the membrane, frequently presents this condition in a typical manner; it looks pale and turbid, contrasting strongly with the deeper parts, and on examination presents infiltration of leucocytes, swelling of the interstitial tissue, sometimes effusion of blood-corpuscles, and a swollen, granular, or fatty state of the muscle-fibres. Although the process may be intense, suppuration rarely occurs, whereas in myocarditis supervening upon inflammation of the endocardium it is, as we have seen, not uncommon. A similar diffuse interstitial process is met with in many of the fevers. In rheumatism, typhus, scarlet fever, small-pox, and diphtheria the myocardium may be found relaxed and soft, the chambers dilated, the substance pale, easily torn, in some instances extremely soft; and this condition has been variously described as inflammatory or degenerative. While not denying that such a state of the muscle-fibre may be brought about by the action of the fever or the influence of some specific poison without any signs of inflammatory action, yet in other instances changes have been found which are evidently of the nature of a myocarditis. In these cases the intermuscular connective tissue is swollen, infiltrated with round cells and nuclei, the vessels are dilated, and often there are minute extravasations and the muscle-fibres are granular and fatty, with indistinct striæ and nuclei. As Leyden[10] has pointed out, this condition probably affords an explanation of some of the cases of sudden death in diphtheria. It may occur without the coarse or microscopic appearance of degeneration of the muscle-fibres, and when of any duration may produce areas of atrophy. Though usually diffuse, it may be patchy and limited in distribution. Martin[11] has described in cases of sudden death in diphtheria and typhoid fever an acute endarteritis of the small branches of the coronary arteries, which probably has a close relationship with this acute interstitial myocarditis.

[Footnote 10: _Zeitschrift für klinische Medicin_, Bd. iv.]

[Footnote 11: _Revue de Médecine_, 1881.]

{606} The SYMPTOMS of acute myocarditis are those of cardiac weakness and irritability, and it is the conditions under which these occur which make us suspect involvement of the myocardium rather than any special features pertaining to the disease. We may reasonably suspect its presence in a case of rheumatism, puerperal fever, or other specific fever when the patient complains of cardiac distress or actual pain, with shortness of breath, and on examination we find a weakened impulse, feeble, indistinct first sound, and a small, irregular pulse. The area of heart-dulness is increased, and there may be a murmur due to muscular incompetence. There is usually fever, but this is generally due to the primary affection. The symptoms are those of a weak and dilated heart, and are peculiar only in the mode of onset and the circumstances under which they arise. A point of note observed by Stokes is the weakening or disappearance of organic murmurs during an attack of acute myocarditis. In acute pericarditis grave implication of the myocardium may be suspected when the pulse gets small and rapid, dyspnoea urgent, and the cardiac pain is increased. Such symptoms, in the absence of copious effusion, would appear to indicate extension of the inflammation to the heart-muscle. Even the occurrence of suppuration has no distinctive symptoms, as it almost invariably occurs as part of a pyæmic process, and the cardiac weakness which supervenes may be regarded as an outcome of the septic or febrile condition. The bursting of an abscess into the pericardium will excite violent pericarditis. In the case of Kortüm, referred to by Friedrich,[12] an abscess in the septum burst into the ventricle; the symptoms, which developed suddenly during a lecture, were a sense of constriction in the chest, dyspnoea, and lividity, and death occurred in six hours.

[Footnote 12: _Virchow's Handbuch_, Bd. v.: "Herzkrankheiten," S. 275.]

The DIAGNOSIS can rarely be made with certainty; at the best we can suspect its presence under the conditions above mentioned.

The course of suppurative myocarditis is always unfavorable, but the fatal termination of the case is usually dependent on concomitant causes. The possibility of recovery in some instances of abscess of the heart is suggested by the occurrence of caseous and cretaceous masses, probably the remnants of collections of pus.

The chief danger in interstitial myocarditis is heart paralysis and sudden death, as occur in diphtheria and occasionally in rheumatism. From mild grades of the disease recovery may take place, and even when general and severe it has often been some indiscretion which has induced the collapse, as sudden sitting up in bed or getting out to attend to the calls of nature. Possibly the slight intramuscular scars and spots of atrophy furnish evidence of past acute myocarditis.

When suspected, the TREATMENT should consist of absolute rest, muscular and mental, with careful feeding and stimulation. If a rheumatic case upon the alkaline or salicylate treatment, the remedies should be stopped. I saw sudden death from heart failure in a case of acute rheumatism in which during four days the full alkaline treatment of Fuller was followed, and in which, by mistake, a much larger quantity of the bicarbonate of soda was given each day than had been intended. Strychnia and small doses of quinine may be given. Shall digitalis be employed in acute myocarditis? Upon this point authorities differ. If we regard it as simply increasing the force of the muscular contractions, we can understand the fear of straining a weakened heart; but digitalis has important trophic influences, and, while it stimulates the vigor of the contraction, improves the nutrition of the heart-muscle and renders it better able to contract. After all, the question amounts to the giving of digitalis in dilatation, and with a weak first sound and feeble action the careful administration, in conjunction with stimulants, will be found beneficial. Peter[13] speaks highly of the application of a blister in the region of the heart.

[Footnote 13: _Loc. cit._]

{607} Chronic Myocarditis (Fibroid Heart).

A condition characterized by the substitution in areas of variable extent of a fibrous connective tissue for the muscular substance. It is an interstitial growth, comparable to the cirrhosis of other organs, and the muscle-elements in the affected regions are wasted or entirely destroyed. The process may occur in a mild grade throughout the organ, but it is more common to find it distributed in certain parts which seem specially prone to this form of degeneration.

The conditions under which it is most likely to occur are those which we find in connection with arterio-sclerosis. It is an affection of adult and advanced life, and is met with most frequently associated with disease of the coronary arteries. In chronic valvular affections it is very common, and may be part of the so-called cyanotic induration or an extension from the thickened endocardium. Sometimes it seems a part of a general arterio-capillary fibrosis. In a few cases there is direct extension from the pericardium. Rheumatism is in this way indirectly responsible; possibly some of the cases are directly traceable to acute interstitial myocarditis occurring in this disease. Chronic alcoholism, syphilis, and gout are prominent factors in the etiology. Some of the most marked cases give no clue in the history or habits of any conditions which we could reasonably connect with the disease. Males are more often affected than females. The tendency to arterio-sclerosis seems to run in some families. Mental anxiety is not without influence, and when the disease is established seems very liable to bring on the anginoid attacks. The situation and extent of the fibrosis are very variable. The papillary muscles and the columnæ carneæ of the left ventricle are most frequently affected, less often the corresponding structures on the right side. The middle portion of the muscular bundles and the apices of the papillæ are first involved. In the latter the process may extend almost to their bases, but on section it will be found that it is more advanced in the superficial than the deep parts. This change is very common in cases of valvular disease with hypertrophy, especially mitral stenosis, but it often occurs in elderly persons who have had no special heart symptoms.

Beneath patches of pearly-white thickened endocardium local fibrosis may occur, often seen at the upper part of the septum in left ventricle, and in the dilated and thickened left auricle of mitral stenosis, and occasionally in other parts. This is usually regarded as an extension from a chronic endocarditis. More rarely the fibrosis extends from a thickened pericardium, but cases are on record of the conversion of the outer layers of the muscular fibres into a firm, hard tissue. We frequently meet with scattered areas of fibrosis in septum and ventricular walls without any implication of peri- or endocardium. During foetal life an endo-myocarditis may occur in the conus of the right ventricle, less frequently in the left, and produce very great narrowing by the gradual contraction of the newly-formed tissue. But the condition to which the term fibroid heart can be most properly given is an extensive affection of the left ventricle, involving most commonly the anterior wall near and at the apex and the lower part of the septum. In these cases there may be marked bulging at the apex, and on section the wall cuts with great resistance, and a dense fibrous tissue of a grayish-white appearance occupies the position of the myocardium. In extreme cases a large part of the septum and anterior wall is in this state, and may present only traces of muscular tissue. There is usually thinning, sometimes thickening, of the affected portions, and the septum bulges toward the right ventricle. The endocardium is opaque, often much thickened, and directly continuous with the fibrous tissue. The columnæ carneæ may be narrow and flattened, and the lacunæ {608} between them very small. The chamber is usually dilated. The upper third of the septum and the base and posterior wall of the ventricle in such cases present a marked contrast to the affected parts, and may look natural, but more commonly are hypertrophied. The other chambers may not show any special change or there may be scattered areas of fibrosis. The thinning and dilatation at the apex and septum are the conditions which precede and lead to the formation of cardiac aneurism. The valves may be normal, but in many cases there is sclerotic endocarditis and retraction. The histological appearance varies much with the stage of the process. When early or where advancing, the muscle-bundles are seen separated by round and elongated cells. The process is usually more marked about groups of fibres, which gradually become isolated by the increase of the growth, and in this way one often sees streaks or patches of muscle-tissue surrounded by the fibrous elements. The destruction of the muscle-cells is apparently by pressure; they gradually waste and present the condition of brown atrophy, the pigment of which remains and indicates the position of the fibres. The intimate pathology of the process is of great interest. Doubtless in some instances we may attribute the fibrosis to an extension of an indurative process from the endo- or pericardium, but the researches of Tautain,[14] Martin,[15] Huber (Karl),[16] and others have thrown a new light on the subject, and it seems probable that in most instances the fibroid degeneration is associated with changes in the coronary arteries. The former describes an endarteritis and a periarteritis of the small vessels, leading to disturbance of nutrition and increase of the connective tissue (sclérose dystrophique). Huber in a considerable number of cases has traced the connection between the arterio-sclerosis, chiefly of the smaller twigs, and the indurative process. The region supplied by the obliterated arteriole is in the condition of an infarct and undergoes an anæmic necrosis, and subsequently by a proliferating myocarditis is transformed into a fibroid area. The condition is well described and figured by Ziegler.[17] Why this obliterating endarteritis should be so limited in the majority of cases to the vessels of the left ventricle is not very clear. The parts most distant from the aorta seem most liable to the process, as the apex and the tips of the papillæ; and it is interesting in this connection to note that the left coronary artery is more frequently diseased than the right.

[Footnote 14: _Thèse de Paris_, 1878.]

[Footnote 15: _Revue de Medicine_, 1883.]

[Footnote 16: _Virchow's Archiv_, Bd. lxxxix.]

[Footnote 17: _Pathologische Anatomie_, Lief. ii., 1884.]

In the milder grades of fibrous myocarditis, when only the apices of the papillæ and thin layers beneath the endocardium are involved, the heart does not appear to be seriously affected; but when of any extent the vigor and force of the contractions are impaired, and the ventricle is unable to do the work of a healthy muscle. Compensatory hypertrophy is not readily established, possibly on account of the arterial sclerosis on which many of the cases seem to depend, although in rare instances, as in a specimen referred to by Quain,[18] there may be very great muscular hypertrophy. Dilatation of the left ventricle is much more apt to follow, as the fibroid walls have not the resisting power of muscular tissue, and the patients finally present a clinical picture of heart failure. The gradual yielding of the fibroid region may result in aneurism.

[Footnote 18: "Lumleian Lectures," _Lancet_, 1872, i.]

There are no characteristic symptoms to indicate the condition. The fibroid heart is a weak heart, and it is scarcely possible to distinguish it from fatty degeneration. A feeble, irregular, sometimes slow, pulse, dyspnoea on exertion, and painful anginoid attacks--symptoms which may have persisted for many years--are special clinical features in many cases. In a patient I examined some years ago for Palmer Howard of Montreal--a typical instance of the condition under consideration--the first symptoms began eight years before death with angina, and there were repeated attacks of cardiac asthma. {609} A careful study of the case was made by Howard[19] extending over several years, and weak heart, dyspnoea on exertion, and anginoid attacks were the prominent symptoms.

[Footnote 19: "Fibroid Disease of the Heart," _Canada Med. and Surgical Journal_, vol. viii., 1880.]

Several very careful studies of the disease have been made within the past few years.[20] Among the symptoms the following may be specially considered. The first place seems accorded by all to the cardiac weakness, and in consequence the pulse is feeble. By some (Rühle) irregularity is regarded as a special feature (delirium cordis), but Ebstein refers to three cases in which the pulse was always regular. Juhel-Renoy also speaks of it as frequent and regular. In many cases the number of beats appears about normal; in others there is a great increase; while in a third set the pulse may be very slow, sinking to 40 or 50 per minute. It is evident that in regard to regularity and frequency of the pulse there are very great differences. In this connection it is interesting to refer to the case of thrombosis of the coronary artery reported by Hammer,[21] in which the pulse sank to 8 per minute.

[Footnote 20: Rühle, "Zur Diagnose der Myocarditis," _Deutsches Archiv f. klin. Med._, Bd. xxii.; Ebstein, _Zeitschrift für klinische Medicin_, Bd. vi.; Leyden, _Ibid._, Bd. viii.--a most important and exhaustive article; Welch, in a paper read before the Medical Section of the American Medical Association, Washington Meeting, 1884; Juhel-Renoy, _Archives gén. de Médecine_, Juillet, 1883.]

[Footnote 21: _Wiener Med. Wochenschrift_, 1878, No. 5.]

Angina is a most important symptom; attacks may recur for years, and death may take place in a paroxysm. Asthmatic attacks are very common: a feeling of impending suffocation, and gasping for breath amounting in some instances to urgent dyspnoea. Oedema of the lungs may occur in these attacks. Fainting and pseudo-apoplectic attacks are frequent symptoms. The physical signs are not very definite or constant. The apex-beat may be displaced and weak, perhaps unrecognizable. With an increase in the area of dulness this is a sign of dilatation. A systolic murmur at the apex is not infrequent. There may be the bruit de galop; gradual heart failure, with general dropsy, is the mode of termination in a considerable number of cases.

The DIAGNOSIS can rarely be made with certainty. The combination of weakened heart, atheromatous arteries, and angina attacks occurring in a person above fifty years of age is certainly suggestive of the existence of this condition; but, as will be seen, this group of symptoms occurs also in fatty degeneration, although the anginoid attacks are probably not so frequent.

In spite of the admirable clinical memoirs above referred to, we are still in need of careful studies of an extensive series of cases, whereby we can get information which will enable us to distinguish more clearly than we can at present the diseases of the myocardium from one another. In this respect our pathological knowledge is in advance of our clinical.

The TREATMENT is largely that of cardiac dilatation and angina, which will be elsewhere considered. The condition is a chronic one, and often associated with hypertrophy, and many of the symptoms are dependent upon failing compensation. Under such circumstances digitalis is indicated, but when there are attacks of angina caution must be exercised in its use.

The Degenerations of the Heart-Muscle.

Under this division we shall consider the following conditions, all of which are characterized by an alteration in the quality and an impairment of function in the affected tissue: 1. Anæmic necrosis; 2. Parenchymatous degeneration; 3. Fatty changes, infiltration and degeneration; 4. Brown atrophy; 5. Amyloid degeneration; 6. Hyaline degeneration; and 7. Calcareous degeneration.

{610} 1. Anæmic necrosis is a condition which results in the heart-muscle when a branch of the coronary artery is blocked either by a thrombus or an embolus, or is obliterated by a progressive sclerosis. The region supplied by the affected vessel is deprived of blood and undergoes a process of infarction. In some instances the tissue is not infiltrated with blood, as in an ordinary infarct, but has a pale yellowish color and is very soft. When there is extravasation the color is more reddish-brown. Histologically, the muscle-cells are found in a state of granular degeneration, and on staining the nuclei do not take the tint, and the whole tissue ultimately assumes the homogeneous granular aspect of coagulation necrosis. There may be fatty degeneration in the contiguous muscle-fibres, and finally, as with infarcts in other organs, fibroid induration takes place. This process, as before mentioned, plays an important part in the production of the fibroid patches scattered through the myocardium. When fresh, the softening of the affected region may be marked, and the name myomalacia cordis which Ziegler[22] has suggested is so far suitable, but it seems more appropriately applied to that condition of general softening of the organ met with in severe fevers. This process most frequently affects the left ventricle, and if extensive may lead to rupture.

[Footnote 22: _Loc. cit._]

The clinical aspects of this condition, as induced by sclerosis of the coronary arteries, have been recently studied with great care by Leyden.[23] In acute cases death occurs in a few hours with symptoms of intense angina pectoris and heart failure. The subacute cases are characterized by recurring anginoid attacks lasting from a few minutes to half an hour. There may be attacks of asthma with heart weakness, and signs of oedema of the lungs. The clinical picture is that of angina pectoris, and the patient may have had similar attacks on previous occasions.

[Footnote 23: _Zeitschrift f. klin. Med._, Bd. vii., 1884.]

2. Parenchymatous Degeneration.--The relation of inflammation of the heart-substance to this degeneration is still somewhat indefinite. I have under Myocarditis described an acute interstitial form characterized by inter-fibrillar swelling with exudation and proliferation of corpuscles, and often granular or fatty degeneration of the muscle-cells. These changes may certainly be regarded as inflammatory, and they are met with either in association with endo- or pericarditis or in connection with specific fevers. Under the term parenchymatous degeneration or cloudy swelling Virchow described[24] a change of frequent occurrence in the heart-muscle and elsewhere, which I think should be distinguished from myositis, although the two processes may lead to alterations difficult to distinguish macroscopically. It is characterized by a pale, turbid state of the cardiac muscle, general, not limited, and a relaxed, soft, brittle condition of the walls. The turbidity and softness are the special features; there are no peri- or endocardial changes--simply the loss of color and consistence. It is the softened heart of Laennec and of Louis; and Stokes speaks of an instance in which "so great was the softening of the organ that when the heart was grasped by the great vessels and held with the apex pointing upward, it fell down over the hand, covering it like the cap of a large mushroom."[25] Microscopically, the fibres are indistinct, the protoplasm occupied by fine granules which obscure the striæ, and sometimes the nuclei. Proliferative changes rarely occur, although swelling and multiplication of the nuclei and the interstitial cells have been described. The granules may be extremely minute, or so large that they are mistaken for fat. They are generally uniform in size, and are scattered irregularly through the fibres. In extreme grades the entire fibre may be occupied by them, and no trace of structure can be seen. Dilute acids and alkalies dissolve the granules, but they resist the action of ether, indicating their albuminous nature. This condition is met with in the infectious diseases--typhoid, {611} typhus, small-pox, pyæmia, remittent fever, etc.--particularly when the disease is protracted and the temperature high. Apparently, we must regard it as an expression of the effect of the poison upon the metabolism of the fibres, inducing a separation of albuminous particles in a granular form. That the high temperature alone does not produce it is demonstrated by its absence in many other diseases in which this condition prevails. The relation to fatty degeneration is not clear. It would appear to precede the development of this change.

[Footnote 24: _Archiv_, vi.]

[Footnote 25: _Diseases of the Heart_, Am. ed., p. 373.]

The effect of this degeneration is virtually the same as that of myocarditis, already described. It produces the weak heart of fever so well described by Stokes,[26] with indistinct impulse, feeble or imperceptible first sound, and progressive diminution of contractile power. There is often a great reduction in the number of beats, which may sink to 40 or 50 per minute. In severe cases of typhoid fever we often have an opportunity of studying the progressive enfeeblement of the heart with weakening or disappearance of the first sound.

[Footnote 26: _Loc. cit._, chap. vii.]

To Stokes we are indebted for the suggestion of the use of alcohol in this condition, and the experience of the past forty years has fully confirmed this practice of the Dublin school.

3. Fatty Heart.--Two conditions of the heart are recognized under this heading--viz. fatty infiltration and fatty degeneration.

Fatty Infiltration.--Cor adiposum, Lipomatosis cordis, and Fatty hypertrophy or overgrowth are synonyms found in the older and more recent works.

A condition in which there is an excess of fat beneath the pericardium and a growth of the same between the fibres of the myocardium. There is normally a certain amount of fat in the cardiac groves, particularly the auriculo-ventricular, and along the coronary arteries. An excess is not infrequently met with in connection with general atrophy, whether the result of disease or the natural decay of old age. Here it serves as padding, and has no pathological significance. In very corpulent persons there is always much subpericardial fat; it forms a part of the general obesity, and in this state an excessive accumulation may lead to a dangerous or even fatal impairment of the contractile power of the heart. Obesity is the expression of a morbid tendency, generally hereditary, to the deposition of fat in the connective tissues. A sedentary life and the consumption of food rich in carbohydrates favor this tendency, but we see it arise under conditions just the opposite when the predisposition to polysarcia is marked. Males are more usually affected than females, at least in Great Britain and Germany.

In the inspection of the bodies of very corpulent persons we find the mediastinum occupied by masses of fat which may completely cover the pericardium. The entire heart may be enveloped in a thick sheeting of fat, through which not a trace of muscle-substance can be seen. Along the groves, the regions of normal deposit, the layer may be an inch or more in diameter. In some cases the muscle-substance beneath seems but slightly involved; there may be superficial infiltration and penetration of columns of fat between the bundles, but the thickness of musculature is normal, and apart from the excessive deposition there is not much amiss. In other instances the muscle-substance is seriously affected; on section of the ventricular wall the fat is seen to infiltrate the entire muscle, separating strands of fibres and reaching almost to the endocardium. There may be places, indeed, in the thinner parts of the ventricular walls in which there appears to be complete substitution of the muscle by fat. Even the papillary bundles may contain adipose tissue. The chambers are usually dilated and the entire organ soft and relaxed. Microscopically, the fat-cells are everywhere {612} seen infiltrating the muscle-tissue, separating the fibres and inducing atrophy. In some cases, even when the condition is advanced, the muscle-fibres appear normal, but in the majority fatty degeneration is also present. Often in these cases the coronary vessels will be found atheromatous.

The SYMPTOMS of fatty overgrowth will depend greatly on the degree of infiltration, the state of the muscle-fibres--whether normal or degenerated--and on the presence or absence of coronary atheroma. Many very fat persons enjoy excellent health and have actively beating hearts, which fail them only on severe exertion, when they get out of wind and experience cardiac distress, perhaps palpitation. The pulse is good and the heart sounds are clear. The signs of heart failure (which may be due either to excessive infiltration or secondary degeneration of the muscle, or both combined) in obese persons are generally very marked--breathlessness on slight exertion, amounting oftentimes to dyspnoea; attacks of asthma of a distressing nature coming on without cause or after a full meal; cough, with or without bronchitis; dizziness and pseudo-apoplectic attacks. Sudden death from syncope or rupture of the heart is common. Dropsical symptoms and cyanosis may supervene. The physical signs are those of heart weakness; impulse imperceptible or very diffuse; area of dulness increased, but often hard to delimit, with fat chest-walls and fatty mediastinum; sometimes a soft systolic murmur at apex; radial pulse rapid, weak, and irregular, in some instances very slow.

The DIAGNOSIS of the condition with such a series of symptoms in an excessively stout person can offer but little difficulty.

The TREATMENT in the early stage should be directed to reducing the general obesity, and such persons should be warned against taking too violent exertion or subjecting the heart to unusual strain. Moderate exercise, mental quietude, and careful dieting may do much toward postponing heart failure, which, when established, calls for the treatment which shall be described under Dilatation.

Fatty Degeneration.--An anomaly or disturbance of nutrition in which minute particles of fat accumulate in the protoplasm of the muscle-fibres, and impair the functional activity of the organ.

This is one of the most common of post-mortem conditions, and in mild grades is met with in a great variety of diseases. The fat is a product of the metabolism of the protoplasm of the muscle-fibres, and in a normal state it (or its immediate antecedents) is oxidized; but when either there is increased transformation or reduced oxidation the products accumulate in the protoplasm, and are evident as minute molecules or as distinct fine oil-droplets. The condition of cloudy swelling or parenchymatous degeneration appears in many cases to precede that of fatty degeneration, and sometimes the granules are of such a size, so abundant, and resemble fat so closely that chemical tests alone can distinguish between them.

A practical division of fatty degeneration is into--1, cases in which the process has attacked a normal heart; and 2, cases in which we find it associated with valvular disease and hypertrophic states of the muscular walls.

In the first group we have _(a)_ The degeneration which accompanies the failing nutrition of old age, of wasting diseases, and of cachectic states. _(b)_ The fatty change in the heart-muscle so often a sequence to, or coexisting with, the parenchymatous degeneration of fevers. _(c)_ The extreme fatty degeneration so constantly associated with profound anæmia. _(d)_ Certain poisons, particularly phosphorus; arsenic, lead, and antimony also act in the same way. The slow poisoning by alcohol is a very frequent cause of a gradually fatty degeneration of the heart. And _(e)_ some local causes are important in inducing this change in the previously normal organ. Pericarditis is almost invariably associated with involvement of the superficial myocardium, {613} either inflammatory or degenerative. Disease of the coronary arteries is a frequent and important cause of fatty metamorphosis. When due to the general conditions above mentioned, the affection is widely distributed in the organ; when the result of gradual narrowing of the vessels by atheroma, the distribution is in the regions supplied by the affected vessels.

The second group comprises those cases in which the fatty degeneration involves the muscle-substance in a condition of hypertrophy, and is an important element in inducing the disturbance of compensation upon which so many heart symptoms depend. Here the process may be more local, affecting, for example, the left ventricle chiefly, as in the hypertrophy from aortic valve disease or in association with contracted kidneys, or the right ventricle in chronic lung affections and mitral stenosis. More rarely we find the process confined chiefly to the auricles, but there may be advanced changes of this nature in the hypertrophied left auricle in mitral stenosis. The fatty degeneration of an hypertrophied heart may be induced by any of the general causes above referred to, but there are also special ones to which it is liable. The chronic congestion which accompanies a dilated heart affects the walls of the organ as well, and diminishes the vigor of the coronary circulation. In emphysema and in mitral stenosis, and other diseases which induce a dilated state of the right heart, fatty degeneration, sometimes combined with fibroid change, is, as Jenner pointed out,[27] very common. This state of the right chambers also interferes with the proper oxygenation of the blood in the lungs, and so acts in a double way. Degenerative changes in the coronary arteries are specially prone to accompany valvular diseases, on which the majority of cases of hypertrophy depend, and we have here one of the most serious causes of fatty degeneration in this state. And, finally, we see this change in some hypertrophied hearts without being able to ascertain any exciting cause: a nutritive breakdown occurs, of which the fatty degeneration is the expression. Possibly in such cases the trophic nerve-influences may be at fault.

[Footnote 27: _Medico-Chirurgical Transactions_, xliii.]

Defective oxidation, in whatever way brought about, seems the common factor in all forms of fatty degeneration. The process may be almost confined to the heart or be more or less general in the solid viscera and voluntary muscles. The diaphragm is sometimes much involved with the heart, even when the other muscles show no signs of the change. There certainly seems to be a special proneness to fatty degeneration in the heart-muscle which may perhaps be associated with its incessant activity. So great is the need of an abundant oxygen-supply that it early feels any deficiency, and in consequence is the first muscle to show nutritional changes.

Fatty degeneration is met with at all ages. I have seen it in the hypertrophied right ventricle of a new-born infant, with stenosis of the pulmonary artery. The cases dependent upon vascular changes are most frequent after middle life. Males appear more frequently affected than females. The form associated with anæmia is an exception to this rule. Stout persons are not more liable to be affected than thin ones; indeed, it is often, to use Paget's phrase, "a lean degeneration." Sedentary habits, worry, grief, and other depressing emotions are believed by some to have a predisposing influence. Persons with gouty and arthritic tendencies are more prone to this change.

The anatomical condition is very characteristic even to the naked eye, and the microscope may be required only in corroboration. It may be local or general. In the former case the left ventricle is most frequently affected, the right ventricle more rarely, and the auricles very seldom. The amount of subpericardial fat may be slight. If the process is advanced and in all the chambers, the heart looks large and is flabby and relaxed. It is pale, of a light yellow-brown tint, buff color, or, as it is sometimes expressed, a {614} faded-leaf color. The consistence is greatly diminished, and the substance tears easily and the finger can be readily thrust through the wall. Extreme grades are met with in profound anæmia and in phosphorus-poisoning. The fatty degeneration of coronary disease and of valvular affections is usually more local, and the heart has often a brownish-yellow tint from the coexistence of brown atrophy. In the left ventricle the papillary columns and the layers of muscle just beneath the endocardium are most affected, and in a curious streaked or patchy way--the tabby mottling of some authors. A similar change may be seen in the right ventricle, particularly in the hypertrophy from mitral disease. In the auricles the right may show patches on the musculi pectinati, but on the left, which is most often affected, the thick endocardium usually obscures it. Chemically, it has been shown that in fatty degeneration the heart may contain from 3 to 5 per cent. more fat than normal.

On microscopical examination of teased portions of the muscle the fibres are broken and irregular, and there is much free fat, in form of droplets, among them. The appearance of the fibres will vary with the intensity of the process; in mild grades there are minute scattered droplets in the protoplasm, not obscuring the nuclei or the striæ; but in an advanced condition the fibres seem occupied completely with minute globules, and no trace of structure can be seen. The patchy distribution of the fatty degeneration in many cases, usually evident to the naked eye, is corroborated by the microscope, and one may obtain portions of the muscle with scarcely a normal fibre, while in a contiguous bit the fibres are little if at all affected. In some instances of general fatty degeneration in anæmia, and even in fevers, as diphtheria, the process is so advanced that it is difficult to find any normal-looking fibres. Brown atrophy is a frequent accompaniment of fatty degeneration.

The effect of this change upon the heart is seen in a diminution of its functional power; the contractile force is weakened and the organ rendered incapable of doing its work efficiently. If the change occurs in a previously normal heart, much will depend on the rapidity with which it has supervened. Repeated hemorrhages or poisoning by phosphorus will induce in a few days an extreme degree of weakness rarely seen in the fatty degeneration of chronic anæmia--perhaps equally extensive. As a consequence of the enfeebled action of the heart, the arteries are not well filled during the systole, and there is anæmia of the organs. The mural weakness readily permits of dilatation, with imperfect emptying of the chambers and distension of the venous system. In hypertrophy the failing compensation is frequently due to the onset of fatty degeneration. During a sudden strain or a more continued effort than usual there may be heart failure, asystolism, or the walls may tear and sudden death occur from rupture.

The SYMPTOMS of fatty degeneration of the heart are by no means definite, being those of defective cardiac power. It is often met with post-mortem when not expected, and on the other hand we may fail to find it even when the symptoms seem to point very clearly to its existence. In chronic anæmia, in chlorosis, in fevers and wasting diseases the process may be extreme, without leading to any more marked symptoms than feeble action of the heart, palpitation on exertion or excitement, with signs of slight dilatation, and a soft mitral systolic murmur from incompetency of the valves. In cases of idiopathic anæmia, in which the fatty degeneration is perhaps more marked than in any other condition except phosphorus-poisoning, the pulse is frequently full, though soft, and regular so long as the patient is quiet. The symptoms of fatty degeneration in cases of valvular disease with hypertrophy are simply those of failing compensation, and we see the same process in the non-valvular hypertrophy of chronic Bright's disease. But, apart from these conditions, fatty degeneration occurs as part of a process of general failure {615} of nutrition, premature or senile. These form the cases of idiopathic fatty heart which seem so constantly to be associated with atheromatous changes in the coronary vessels. English writers have dealt specially with this form, which certainly appears to be more prevalent in Great Britain than on this continent or in Europe. In these cases there may be general obesity, but as often the subjects are of spare habit, with full atheromatous arteries, and other indications, perhaps, of early senility. They are usually persons who have lived freely and taken stimulants in excess. Among the symptoms believed to indicate fatty degeneration in these cases are--weak, irregular action of the heart, with a small intermittent pulse; cardiac pain, sometimes anginoid in character; dyspnoea, particularly on exertion, as in ascending an incline; signs of cerebral anæmia, indicated by vertigo or pseudo-apoplectic attacks and loss of mental power; the presence of an arcus senilis; and, as a final symptom, Cheyne-Stokes respiration.

Persistent irregularity in the action of the heart in a person with atheromatous arteries, and dyspnoea on exertion, without signs of valvular affection, are certainly suggestive of degeneration of the muscle-fibres of the heart. In some instances there has been noted a greatly diminished number of beats, 40 or 50 per minute, or even slower. Irregular action of the heart may, however, persist for years without indicating any serious mischief.[28] The yellow fatty arcus senilis is believed by many physicians to indicate a weak fatty heart, and it does occur in many persons of soft flabby habit of body with degenerated arteries and evidences of premature decay; but by itself it is of no value as a sign of vascular degeneration. It must not be confounded with the opaque white calcareous arcus not uncommon in elderly people, and met with occasionally in middle-aged persons. The Cheyne-Stokes breathing so often referred to as specially associated with fatty heart is, in my experience, a much more frequent concomitant of uræmic states.

[Footnote 28: In the spring of 1882, I saw, for Geo. W. Campbell, a gentleman aged eighty-two, a man of remarkable vigor, mental and bodily. He had an extraordinarily irregular yet full pulse, with atheromatous arteries--a condition which he assured me had been constantly present for close upon forty years, and had been a source of needless anxiety to many physicians, and for some years to himself.]

The physical signs of fatty degeneration of the heart are a weak impulse, often diffuse, and if the patient is thin the area of dulness may be found increased. In stout persons it is difficult to determine dilatation on account of the fat inside and out. The sounds on auscultation are generally weak, distant, and muffled, but in the fatty degeneration of anæmia the first will often be found sharp and distinct, though short and more like the second sound. A soft murmur, systolic in character, is not infrequently heard at the apex, and believed to be due to muscular incompetency.

The DIAGNOSIS is beset with difficulties, and in most cases we have to be content with probabilities, except in the instances due to anæmia, etc. Permanent weakness of impulse and the symptoms it entails, with signs of degeneration of tissue as shown by atheromatous arteries, are the most suggestive features, but even about them there are uncertainties. My own errors and a contemplation of those of several very eminent clinicians, taken in connection with the fact that some of the most typical cases of fatty heart which come under my observation have been instances of sudden death in persons pursuing their avocations, have made me very cautious in the diagnosis of this condition.

The PROGNOSIS depends entirely on the circumstances under which the degeneration has developed. In the weak fatty heart of chlorosis and anæmia, with a return to a normal blood-condition, the nutrition of the heart is improved and its action strengthened. Doubtless many cases of failing compensation are due to it, and a subsidence of the symptoms under {616} rest, digitalis, and careful feeding may simply mean improved nutrition of heart-muscle and disappearance of the fat which clogs its action. Where due to atheromatous changes, no permanent improvement can be expected; and in these cases, particularly if combined with fatty infiltration, rupture or fatal syncope may occur. In not a few of such cases the persons have not complained either to their physicians or friends of cardiac distress. The case of the celebrated Scotch divine, Chalmers, described by Begbie,[29] is an illustration of advanced fatty heart with sudden death in a man of extraordinary vigor of mind and body.

[Footnote 29: _Contrib. to Pract. Med._, 1862.]

The TREATMENT should be directed to the removal of the cause when possible, as the anæmia, febrile condition, etc. In all cases rest, quiet, and avoidance of excitement are to be rigidly enforced. Sudden exertions may prove instantly fatal. In the cases where there is hypertrophy with or without valvular disease, and the failing compensation is due to this cause, digitalis acts well, and should be combined with stimulants. In the senile and atheromatous cases great care must be exercised: the bowels should be kept loose, and the patient cautioned not to strain at stool or make any sudden exertion. He should lead a very quiet, regular life, and exercise great moderation in food, drink, and venery. Warm and Turkish baths are most dangerous. Iron, arsenic, and nux vomica are remedies from which benefit may be expected. Digitalis is, as a rule, contraindicated. We must remember that, as Sir William Jenner has remarked, fatty degeneration is sometimes a preservative lesion, and induces a due proportion between the cardiac strength and the arterial resistance, reducing the former when there is great atheroma and brittleness of the vessels. The application of blisters is often of use in allaying the pain, and nitrite of amyl should be given in the anginoid attacks.

4. Brown atrophy is a very common degenerative change in the heart-muscle, particularly in the hypertrophied organ of valve affections. In old people and in persons dead of wasting diseases it seems invariably present. When advanced, the color of the muscle is quite distinctive--a dark red-brown and the consistence may be greater than normal. Microscopically, the fibres present a central accumulation of brown pigment, generally arranged about the nuclei and extending up and down the cells. The cement-substance between the cells is often unusually distinct in these cases, and seems more fragile than in healthy muscle. The composition of the pigment has not, so far as I know, been determined, but it is doubtless, like that of the brown induration of the lung and red atrophy of the liver, derived from the hæmoglobin, and possibly, as in these latter conditions, is connected with feeble venous circulation.

5. Amyloid degeneration of the heart is occasionally met with, but rarely in so advanced a grade as to be recognizable macroscopically. It occurs in the intermuscular connective tissue and in the blood-vessels, not in the fibres, and occasionally may be extensive, as in a case mentioned by Ziegler.[30]

[Footnote 30: _Pathologische anatomie_, 3te Aufl., Lief. i., §59.]

6. The hyaline degeneration of Zenker is sometimes seen in the heart-muscle in cases of prolonged fever. The affected fibres are swollen, homogeneous, translucent, and the striæ very faint or entirely absent.

7. Calcareous degeneration may occur in the myocardium, involving the fibres and forming a definite calcareous infiltration of the protoplasm, as well figured and described by Coats.[31] It is a rare condition, whereas extensive calcified plates in endo- and pericardium are by no means uncommon.

[Footnote 31: _Pathology_, 1883.]

{617} Spontaneous Rupture of the Heart.

Laceration of the wall of the heart is usually associated with fatty infiltration or degeneration, most frequently the latter. It is doubtful if in any instance the healthy muscle has broken. Rare causes are--acute softening, in consequence of embolism of a branch of a coronary artery; abscess from pyæmia; or an acute ulcer of the endocardium. Cysts simple or hydatid are mentioned, but the extreme rarity of causes other than fatty changes may be inferred from the statistics of Quain,[32] who states that of 100 cases of rupture collected by him, fatty degeneration was noted (microscopically) in 77, and in the others there was softening in all but 2, or no mention was made of the condition of the wall.

[Footnote 32: _Loc. cit._]

Males are more frequently the subject of this accident than females, and the great majority of cases occur in persons over sixty years of age--two-thirds of the eases tabulated by Quain.[33]

[Footnote 33: _Loc. cit._]

The rent may occur in any of the chambers, but the most frequent site is the left ventricle on the anterior wall, not far from the septum. Statistics give, for 55 cases,[34] 43 in left ventricle, 7 in right ventricle, and 3 in right auricle and 2 in the left auricle.

[Footnote 34: Elleaumé, _Essai sur les Ruptures du Coeur_, Paris, 1857.]

The break is generally a ragged, irregular rent in the course of the fibres, and the trajét may be oblique and crossed by strands of muscle. The internal orifice may be larger than the external; the opposite is rarely the case. Two or more rents have been found. Usually the fissure is not very long--from a quarter of an inch to an inch--but there are cases of long rents extending from base to apex. Clots usually block the orifices, and the pericardium also contains large coagula. Evidence is sometimes found to indicate that the tear has occurred slowly, as attempts at repair may be present.

The wall in the vicinity of the break has usually been found in a state of degeneration, and we can readily understand how sudden and violent contractions might strain a weak part and tear the substance. Perhaps irregularity in the contractions may be an important factor, such as we may suppose occurs when a wave of contraction reaches a patch of advanced fatty change or softening from embolism.

The accident usually takes place during exertion or excitement. Many cases are reported during straining at stool, others while lifting weights, running, or during coitus. Cases are mentioned as occurring during sleep or while at rest.

There may be no preliminary symptoms, and without warning the patient falls, and with a few gasps or a cry is dead. This occurred in 71 of the 100 cases collected by Quain. In other instances there is great pain in the præcordial region, a sense of suffocation and anguish, with vomiting, and life may be prolonged several hours. In one instance the patient lived eleven days.[35] Probably in such cases there is a small rent at first which gets blocked with clots, and only a small amount of blood oozes into the pericardium with each systole. The symptoms may be those of simple heart failure, as in a case I examined for Burland of Montreal, in which the patient lived thirteen hours after the onset of the symptoms, and was able, though with difficulty, to continue his walk up a rather steep hill.[36] Death appears to occur from shock or syncope, sometimes from compression of the heart by the extravasated blood. In the case just mentioned the amount of blood in the pericardium was {618} very much less than I have seen in cases of rupture of an aneurism into this sac.

[Footnote 35: Barth, _Archiv. générales_, 1871.]

[Footnote 36: This was a case which illustrated well the latency of many cases of fatty heart. The patient was an active merchant, aged sixty, who had never complained of cardiac trouble, and had only a short time before his death effected a reinsurance upon his life for a large amount.]

In protracted cases the nausea and vomiting may for a short time lead to the supposition that the case is one of severe indigestion, but, as mentioned above, in the great majority of cases death occurs at once, and in the others there can rarely be any question of diagnosis, and still less of treatment.

Atrophy of the Heart.

DEFINITION.--A diminution in size and weight of the organ, due to degeneration and atrophy of the muscular fibres.

The old writers applied the term phthisis of the heart to this condition. The decrease is always in weight, and usually in size; it is doubtful if there is an atrophic and dilated heart in which, with the wasting, the size is maintained by the dilatation. In many of the degenerations, particularly fatty and fibroid, there is local atrophy of the muscle-fibres and yet the weight and size of the organ are not changed.

The varieties which have been recognized correspond to those of hypertrophy--viz. the simple, eccentric, and concentric forms, but the two latter are probably only conditions of contraction or dilatation in a wasted heart. The post-mortem contraction in the small left ventricle of persons dead of chronic disease may be excessive; and here, as in concentric hypertrophy, the examination must be made with care.

ETIOLOGY.--The atrophy is either congenital or acquired. The congenital atrophy which is most frequently seen in women is in association with defective development of the arterial system and the generative organs. This is occasionally very marked in chlorosis, and is described and figured by Virchow in his monograph on this subject.[37] But apart from this general hypoplasia of the heart and vessels in women, we sometimes in the post-mortem room find in a man, dead perhaps of an acute disease and without any cardiac symptoms, a heart small out of all proportion to the size and general nourishment of the body. Many of the older writers mention this. Gowers refers to a case which Allan Burns narrates, in which the heart of an adult was not larger than that of a child of six or seven. Morgagni has a similar observation.

[Footnote 37: _Ueber die Chlorose_, Berlin, 1872.]

The great majority of the cases are secondary or acquired, and are met with in the wasting diseases, as cancer, phthisis, prolonged suppuration, and diabetes. The cardiac wasting is part of the general marasmus which affects the whole body. In about half the cases of phthisis the heart is small.[38] In cancer of the pylorus the most extreme wasting has been found. Disease of the coronary arteries is an occasional cause, but it most frequently produces local atrophy or degeneration. Compression by pericardial effusion, fatty infiltration, and pericardial adhesions are mentioned as rare causes.

[Footnote 38: Quain, _loc. cit._]

A rough guess at the proportional size of the heart may be made by comparing it with the closed right fist of the person. Weighing gives the most accurate test, and in each instance regard must be had to the size of the body. In some instances the organ has weighed only two or three ounces. The heart figured by Bramwell,[39] one of the smallest on record, weighed only 2 ounces and 2 drachms. Quain[40] refers to one, from a girl aged fourteen, which weighed only 1 ounce 14 drachms.

[Footnote 39: _Diseases of the Heart_, 1884.]

[Footnote 40: _Loc. cit._]

Usually, in secondary atrophy, the visceral pericardium is wrinkled and the coronary arteries prominent and tortuous--two features of great importance in determining atrophy and in distinguishing between the acquired and {619} congenital forms. The pericardial fat is variable in amount. Microscopically, brown atrophy is the most constant change; fatty degeneration much less common. Senile atrophy may present very similar appearances. The heart may be tough and firm from an increase in the fibrous elements. The pericardial fluid I have often noticed to be much increased.

There are no characteristic SYMPTOMS. The heart-muscle may be able to fulfil the requirements of the wasted frame. A feeble impulse and diminished area of dulness may be present, but in the marasmus of middle-aged or elderly people emphysema of the anterior margin of the lung may seriously interfere with a proper examination. The increased pericardial effusion occurs toward the end. The heart sounds are feeble and the pulse weak. Palpitation is frequent, and there may be the usual signs of anæmia, dizziness, etc.

The condition may be suspected, but is rarely diagnosed during life.

The PROGNOSIS depends upon the disease to which the atrophy is secondary, to the amelioration of which also the treatment must be directed.

Hypertrophy of the Heart.