Chapter XLVII: Part 47

Palpation.--The apex-beat is indistinct, except in cases where there is marked hypertrophy of the left ventricle. Pulsation occurs in the epigastrium, which may be due to reflux into the enlarged hepatic veins or to the fact that the dilated and hypertrophied right ventricle so presses on the liver that the impulse is conveyed through the diaphragm with each cardiac pulsation. Guttman thinks epigastric pulsation is due wholly to reflux into the veins of the liver, and not to right ventricular pulsation.

{680} Early in the disease the impulse in the jugulars is confined to the lower part of the vessels, particularly to the sinus. Beyond this point the vein merely undulates. Later, a systolic pulsation is felt as high up as the angle of the jaw, and may be accompanied by distinct though feeble presystolic pulsation.

The liver may first simply undergo systolic depression, chiefly at the left lobe; secondly, the whole liver may have an impulse coming from an enormously dilated vena cava; and thirdly, the systolic pulsation of the veins within the organ may give to it a palpable expanso-pulsatory movement. The hepatic pulsation is rhythmical with the cardiac impulse. In rare cases it precedes jugular pulsation. Sometimes pulsation is felt in the femoral veins.

Sphygmographic tracings of the jugular pulse show it to be dicrotic.

Percussion shows an increase in the area of cardiac dulness to the right and upward, sometimes as far as the second intercostal space.

Auscultation.--The murmur of tricuspid insufficiency is heard with, or takes the place of, the first sound of the heart; it is superficial, of low pitch, blowing, soft, and faint, and is heard with the greatest intensity over the lower part of the sternum, at its left border, between the fourth and sixth ribs. It is rarely audible above the third rib or to the left of the apex-beat. This murmur is transmitted from the region at the base of the xiphoid cartilage upward and to the right from one to two inches. Sometimes it is heard only over a very limited area, and then it may be overlooked.

DIFFERENTIAL DIAGNOSIS.--A tricuspid regurgitant murmur may be confounded with that due to aortic obstruction, pulmonic obstruction, and mitral regurgitation. A tricuspid regurgitant murmur is never audible above the third rib; is not accompanied by an accentuation of the second sound over the pulmonary artery, but by jugular and epigastric pulsation; and is heard with maximum intensity near the base of the ensiform cartilage. These points are sufficient to differentiate it from an aortic or pulmonary obstructive murmur. The differential diagnosis between it and a mitral regurgitant murmur has been given.

PROGNOSIS IN VALVULAR DISEASES OF THE HEART.--Any statements as to the duration of life in valvular diseases of the heart, and their relative frequency as a cause of death (especially of sudden death), must be based upon personal observation, and necessarily will differ with different observers.

In order to establish, if possible, a basis of comparison for the different valvular lesions, I give a résumé which I have made of 81 cases, in all of which autopsies were made and the diagnosis of valvular disease verified.[25]

[Footnote 25: _Med. Rec. N.Y._, April 1, 1870, p. 66 _et seq._]

In 14 cases of various valvular lesions, each of which was accompanied by cardiac hypertrophy and dilatation, 50 per cent. of the deaths were due directly to the valvular lesion. In 1 of these, where there was stenosis at both auriculo-ventricular orifices, death was sudden.

In 15 cases of valvular disease, in which there was only cardiac hypertrophy, there were 11 deaths from the heart lesion. In 5 of these death occurred suddenly, and these 5 sudden deaths were all directly due to the heart lesion.

In 6 cases of valvular disease accompanied by dilatation alone, 4 deaths resulted directly from the heart lesion, and 2 of these were sudden.

In 15 cases where the aortic valves were involved (either calcified, rigid, or atheromatous) the heart lesion was not the cause of death in any case. Of these 15 cases, sudden death occurred but in 2; in 1 there were firm and long-standing pericardial adhesions, and in the other cerebral apoplexy.

In 12 cases of calcification of the mitral valve, no death occurred as the direct result of the valvular lesion, and there were only 2 sudden deaths, both from cerebral apoplexy.

{681} The aortic and mitral valves were diseased in 14 cases; in 2 of these only did death result from the heart lesion, and the only three sudden deaths in this class were from uræmia, apoplexy, and croupous laryngitis.

The aortic and pulmonic valves were both diseased in 3 cases which died suddenly, and in no instance was death due directly to the heart lesions.

In 2 cases there was disease at the aortic, mitral, and tricuspid orifices, and no sudden death.

Thus it will be seen that of these 81 cases, in 24 only was death due directly to the heart lesion. There were only 8 sudden deaths due directly to the heart lesion.

The results of personal, clinical, and pathological observation lead me to the opinion that the loudness, harshness, and the area of diffusion of any cardiac murmur have little to do with its prognosis.

I deduce from the above-mentioned cases that cardiac murmurs rarely necessitate a bad prognosis unless hypertrophy and dilatation coexist; but so soon as the signs of considerable dilatation and hypertrophy are present a great variety of complications are liable to occur.

In 1870, I had a patient sixty years of age with extensive aortic reflux, who had been under my observation eight years, during which time he had three attacks of pneumonia. There were no appreciable signs of cardiac dilatation in his case.

Walshe says: "The order of relative gravity, as estimated not only by their ultimate lethal tendency, but by the amount of complicated miseries they inflict, is--1, tricuspid regurgitation; 2, mitral obstruction and regurgitation; 3, aortic regurgitation; 4, pulmonic obstruction, 5, aortic obstruction."

The following are conditions which render the prognosis in each valvular lesion more or less unfavorable:

In aortic stenosis the prognosis is less grave than in any other valvular lesion. Life may be prolonged and good health enjoyed for many years. Yet it must be remembered that extensive aortic stenosis rarely exists without attendant regurgitation.

So long as the hypertrophy of the left ventricle compensates for the obstruction, the prognosis is good; but when the hypertrophied walls fail to overcome the obstruction, dilatation begins, and the ventricular systole becomes feeble and intermitting, and the arterial supply to the brain is so much diminished as to lead to cerebral anæmia.

If after sudden exertion or violent muscular effort there is interruption or great irregularity in the heart's action, sudden death may occur from a complete arrest of the ventricular systole.

Evidences of excessive hypertrophy and dilatation, the occurrence of syncope, signs of cerebral anæmia, attacks of vertigo, great muscular prostration, continued and marked paleness of the face, and irregularity of the pulse, render the prognosis exceedingly unfavorable in aortic stenosis.

If the presence of vegetations can be determined, there is danger from cerebral embolism.

When there are no evidences of alterations in the ventricular walls after an aortic obstructive murmur has existed for some time, it may be assumed that no vegetations exist on the valves, and that the murmur is not due to extensive aortic stenosis, and consequently is not dangerous to life.

When the mitral valves become involved, the combined lesions render the prognosis unfavorable.

Death may result from cerebral complications, pulmonary oedema, or cardiac degeneration.

Aortic insufficiency is a much graver form of valvular disease than aortic stenosis. It is difficult to estimate the probable duration of life in aortic {682} insufficiency, for it frequently gives rise to no symptom that would lead to its diagnosis until it is far advanced. Twenty-one days and five years are the extreme limits that have been recorded. It must always be borne in mind in estimating the factors for and against a good prognosis that in no other valvular lesion is sudden death so liable to occur. Yet the record of the cases which I have given (page 680) indicates that mitral stenosis is nearly, if not quite, as frequently a cause of sudden death.

A diseased valve can never be restored to its normal functions, and the shorter and more gushing the murmur the more extensive the regurgitation. The effects of the regurgitation must be carefully estimated before a prognosis can be given in any case. When one aortic flap is puckered and shrunken, the other two may elongate and compensate for the patency. But this occurs only in very young subjects.

Aortic regurgitation is, however, more serious in the very young than in adults. In children the valvular changes are less atrophic and more inflammatory in character.

Where the disease is met with in middle life, in those who daily undergo severe mental or bodily strain, the prognosis is unfavorable. And when in such patients there are the evidences of arterial degeneration or a tendency to it, the dangers are greatly increased, for the hypertrophied ventricle drives out the blood from its dilated cavity with greater than the normal force, and the vessels being weakened there is great danger of their rupture; hence the frequent occurrence of apoplexy and infarctions. In the very old I have seen aortic incompetence last a long time and cause little inconvenience.

Again, the prognosis is bad when cyanosis and dropsy result from the failure of a dilated and hypertrophied left ventricle to empty itself. This weakness is the result of that interference with the coronary circulation which brings about impaired nutrition, and therefore degeneration of the heart-walls.

When mitral insufficiency is secondarily induced, then obstruction to the systemic circulation leads to induration of the liver and kidneys, which interferes with the performance of their functions and hastens the fatal issue.

Sudden rupture of a valve or valvular disease that has developed very rapidly is more dangerous than when the valvular insufficiency is slowly developed. The flap or flaps involved can sometimes be determined during life, and then the prognosis will be more or less favorable according as the anterior or posterior are incompetent. In all cases the prognosis depends more upon the condition of the heart-walls and on the general nutrition than upon any other element.

When aortic regurgitation is complicated by aortic stenosis, mitral regurgitation, or by the vascular and visceral conditions resulting from the derangement of the circulation, the prognosis is exceedingly unfavorable. Death may result from embolism, apoplexy, dropsy, pulmonary oedema, from sudden cardiac insufficiency, or from visceral complications. When the radial impulse is felt a little after the apex-beat, it is always important to determine whether the action of the heart remains regular under mental excitement or violent physical exertion: if it does, the prognosis is far better than when it becomes irregular.

Mitral stenosis admits of but slight compensation; if extensive, it is always a grave disease. The prognosis in any case can be estimated by the severity of the thoracic symptoms. When physical exertion greatly exacerbates the thoracic symptoms, the prognosis is especially bad; for during violent exercise such patients are not only liable to pulmonary congestion and oedema, but to pulmonary infarctions and pulmonary apoplexy with large extravasations.

Where mitral stenosis is extensive it ranks next to aortic regurgitation in its danger of sudden death. The statistics furnished by Bellevue Hospital show sudden death to occur as often in mitral stenosis as in aortic reflux.

{683} Congenital mitral stenosis is not dangerous, and does not cause much embarrassment, for it is invariably associated with hyperplasia of the pulmonary arterial system. The later in life mitral stenosis occurs, the more unfavorable the prognosis.

Mitral regurgitation uncomplicated by any other valvular lesion gives rise to very little disturbance of the systemic or capillary circulation. It is more often fully compensated for than any other valvular lesion. The changes which lead to it are of slow growth and their tendency is to remain stationary. Patients with a moderate regurgitation at the mitral orifice suffer very little except during or after violent physical exercise, and, were it not for the slight dizziness which attends it, it would pass unnoticed. As long as the compensatory hypertrophy of the right ventricle is sufficient to overcome the obstruction to the pulmonary circulation, patients with this form of heart disease may not suffer from dyspnoea even after violent physical exercise. As regards the duration of life, the prognosis in mitral regurgitation is good. When, however, mitral stenosis and regurgitation coexist, the liability to sudden pulmonary complications becomes so great that a very guarded prognosis must be given; and it must be remembered that combined reflux and stenosis at the mitral orifice is a frequent combination.

In very many instances it is unnecessary to tell a patient with mitral reflux that he has an incurable heart disease, for with no other valvular lesion the individual may live to advanced life. But when it is combined with mitral stenosis it must be regarded as a very serious form of valvular lesion. As soon as symptoms occur that show failure of the right heart, the prognosis becomes unfavorable. Oedema of the extremities or fluid in any of the serous cavities, cyanosis, dyspnoea, and hæmoptysis, are indications of such failure.

Death may result from general anasarca, from serous effusions into the pleuræ, peritoneum, or pericardium, from pulmonary oedema and congestion, or from heart-insufficiency.

Extensive obstruction or regurgitation at the pulmonic orifice would necessarily lead to serious results, but there are no reliable data upon which the prognosis can be based.

The prognosis in tricuspid obstruction and regurgitation, when associated with mitral disease, is very grave; but it is not as bad as when it results from chronic bronchitis and pulmonary emphysema.

When in any case jugular and epigastric pulsation are marked, the changes in the various organs of the body already referred to rapidly ensue. Walshe says that "tricuspid regurgitation is the worst of all valvular lesions." Patients with tricuspid reflux are in extreme danger from intercurrent attacks of acute pulmonary hyperæmia.

Tricuspid disease, of all valvular lesions, leads most rapidly to cyanosis and dropsy.

TREATMENT.--The treatment of aortic stenosis and of aortic regurgitation may be summed up under three heads--viz. rest, diet, and regimen.

Rest is most important; it must be mental as well as physical; the appetite, emotions, and passions must be kept under perfect control: these indications are best maintained by a sedentary country life. Straining, especially when the hands are above the head, should be carefully avoided.

The stomach also must have all the rest compatible with the most perfect nutrition; it is frequently a difficult matter to combine both indications, for it should be remembered that the more perfectly the nutritive processes are maintained the longer will the cardiac muscle resist degeneration. Sugar, sweet vegetables, and animal fat must be sparingly indulged in. The food should consist of nitrogenous, albuminoid material, and should be taken in quantities that do not disturb the heart's action.

{684} In aortic incompetence patients in sleeping should assume, as nearly as possible, a horizontal posture. By lying on their backs they lower the height of the distending column of blood, and thus relieve both the cardiac circulation and the tendency to pulmonary congestion. Sometimes, when defective aortic pressure reacts injuriously on both the gastric and hepatic secretions and limits both their supply and their efficiency, moderate alcoholic stimulation may be cautiously employed to tide over a weakly period. The bowels should be gently moved once daily. That the cutaneous circulation may be active the body should be warmly clothed. Any prolonged exposure of the surface to cold is to be avoided. In winter the warm bath may be occasionally used, and in summer the patient is frequently benefited by a warm sea-water bath.

Medicinal agents are not to be resorted to until the cardiac hypertrophy fails to be compensatory. Then relief is demanded for the failing heart-power. In aortic regurgitation with feeble heart-action the tincture of digitalis and the tincture of the perchloride of iron are to be given in ten-minim doses three times a day. The iron is especially indicated whenever anæmia is evidenced. Digitalis is given to produce a sedative action, and therefore should be given in very small doses and regulated according to its effects on each patient. An infusion of the English leaves is the preparation which is most reliable, although the tincture, if fresh and well prepared, is equally good. When rapid and immediate action is demanded, digitalis may be given hypodermically. There is one guide to its use not unimportant to remember: that is, as long as it causes an increase in the flow of the urine it is safe to continue its use. When vertigo and syncope are prominent symptoms quinine and strychnia may be given with the digitalis. When the heart in aortic reflux acts with violence and rapidity, and the arteries are in a state of high tension, aconite will be found of service in quieting the heart's action. In aortic incompetence small doses of arsenic seem to have a stimulating effect, especially when given with digitalis and iron. Iron may disturb the stomach, arsenic seldom if ever does. It is always a safe rule when giving iron to administer at the same time a bitter vegetable infusion, as quassia or columba.

When the hepatic and gastric vessels are engorged, three or four leeches over the liver or epigastrium, followed by a warm fomentation, will afford temporary relief.

At no time should a large quantity of fluid be taken into the stomach. Symptoms of angina pectoris, with local pain and dyspnoea, are evidences of aortitis. This demands the application of leeches over the sternum and continued small doses of mercury.

The treatment of dyspnoea, dropsy, pulmonary oedema, and other late and distressing symptoms will be considered in connection with mitral disease. Sometimes the pain of aortic disease is so severe as to require an anodyne for its relief: opium must not be given by the mouth, but the sulphate or the hydrochlorate of morphine can be safely given hypodermically. The severe angina-like pain of aortic regurgitation can often be promptly relieved by the nitrate of amyl.

Barlowe and Fagge both advise senega and ammonia carbonate for the less severe effects of aortic reflux. They advance no reason for the use of these drugs, but their cases show that they have a markedly beneficial effect. All authorities unite in regarding aortic insufficiency as less amenable to treatment than other valvular lesions.

In all cases the idiosyncrasy of each patient should be carefully considered.

No treatment can restore a diseased valve to its normal condition, or prevent, for any considerable time, cardiac dilatation and hypertrophy when the normal function of the valves is greatly interfered with.

{685} The first step in the treatment of a serious lesion at the mitral valves is to make the patient clearly understand his exact condition, that he may see the reasonableness of the advice given, for his treatment for the most part must be carried on by himself. A patient must be fully persuaded of its necessity before he will regulate his habits and mode of life in accordance with the requirements of his case. The rules as to nutrition are the same as those to be observed in aortic stenosis and reflux. There should be a gentle and regular daily evacuation from the bowels. Straining at stool must be avoided, and any use of alcohol, strong tea, coffee, and tobacco is to be prohibited. If in either form of mitral valvular disease the patient is anæmic, iron should be given. This is given as a food to such patients, and is best administered about half an hour after meal-time. Ten or twenty grains of Vallette's mass may be given with benefit to anæmic patients two or three times a day for a long period.

Patients with mitral reflux should avoid a prolonged use of the voice, especially in speaking or singing. Small doses of quinine and strychnine, alternating with the administration of iron, are often of service. If there is anorexia, infusion of quassia or columba may be given with the iron. The triple phosphates of iron, quinine, and strychnine, or small doses of dilute sulphuric acid, will be found to improve the condition of these patients when they show signs of extreme debility.

In every case of mitral disease there comes a period when the pulmonary hyperæmia shows that the compensation of the right heart has failed. An adjustment of the heart to the circulation is now effected by the judicious administration of digitalis. Digitalis should only be given at those times when the heart-failure is imminent and there is marked pulmonary congestion. Half an ounce of the infusion every two hours for twenty-four or forty-eight hours is often required to overcome the heart-failure. The time will come when digitalis ceases to have its sustaining effect upon the heart-muscle; hence it should always be most sparingly and carefully used, and the patient should never be allowed to use it continually.

When the pulse is rapid, feeble, and irregular, more time is needed for the flow of blood into the ventricle, and greater force and regularity in the ejection of the blood from that ventricle are demanded. Digitalis fulfils all these conditions: the pulse becomes regular, beating about sixty per minute, full and forceful. The urine, before scanty, now becomes abundant and normal. Pulmonary engorgement diminishes, and commencing dropsy gradually but totally disappears.

Hayden advises ten minims of the spirits of chloroform and fifteen minims each of the tincture of digitalis and the tincture of the perchloride of iron in an ounce of water every three hours.

Whenever asystolism is present or suppression of urine is threatened, digitalis should be given whether the other indications are present or not. In most cases of mitral stenosis it is best to avoid the use of digitalis as far as possible.

The dropsy which accompanies advanced mitral regurgitation may be promptly relieved by compound jalap powder, combined with calomel in sufficient quantity to produce prompt and free catharsis. In some cases of cardiac dropsy, squill, juniper, brown cream of tartar, and copaiba act as diuretics. This latter drug is best exhibited in the form of the resin.

In mitral reflux a combination of digitalis and nitrous ether will often be found to act as a diuretic. In all cases when a diuretic is given in heart disease the loins should be cupped or warm poultices applied and the bowels freely purged. In copious hæmoptysis in cardiac disease ergotin may be given in full doses either by the mouth or hypodermically.

The hæmoptysis which accompanies pulmonary apoplexy of heart disease {686} sometimes temporarily relieves the dyspnoea. On this basis Dickenson and Fagge and other English writers recommend venesection for the relief of the pulmonary engorgement or heart-failure. Pain in the præcordial region which accompanies valvular insufficiency may sometimes be relieved by the application of leeches over the præcordial space. Hyoscyamus, hydrochlorate of morphia, nitrate of amyl, chloroform, and a belladonna plaster over the præcordial space have all been employed for the same purpose.

It is to be remembered that such pain is the cry of the heart-muscle for a higher degree of nutrition.

Bleeding in heart disease favors dropsy by thinning the blood and by diminishing the heart-power. It should never be resorted to except in great emergencies. Niemeyer advises arsenic and antimony in mitral valvular disease, but does not say in what cases or for what reason they are to be used. When in the late stages of mitral disease the free use of digitalis fails to regulate the pulse and to relieve the pulmonary engorgement, its prolonged administration does harm rather than good; but in every case of mitral disease where the drug has not been used it may be safely affirmed that its administration will give prompt relief.

If it becomes necessary to use an anodyne or hypnotic at any period in the course of mitral valvular disease, morphia hypodermically is to be preferred to all others.

The rules in regard to hygiene, diet, and exercise which have been given for the management of mitral disease are equally indicated in the management of pulmonary obstruction or regurgitation. Beyond this their treatment is purely symptomatic.

The treatment of tricuspid obstruction depends upon the gravity and sequelæ of the accompanying disease--viz. mitral. Stenosis of the tricuspid orifice never occurs until mitral obstruction is excessive, and the latter condition is always the predominant one.

The same rules of hygiene and diet which have already been given for mitral disease must be followed with the utmost care by those suffering from tricuspid reflux. The patient must lead a life of perfect quiet, and should live in a warm, equable climate. When occurring with mitral disease digitalis should not be omitted; for although the drug, by increasing the action of the heart, would seem to be injurious, yet it promotes ventricular contraction, and thus tends to relieve the tricuspid pressure. In tricuspid insufficiency with pulmonary emphysema this drug should be very cautiously exhibited, and its use or omission must depend upon the effects produced in each case. If the cerebral symptoms are exaggerated, it must be discontinued. The indications for the use of tonics, such as iron, quinine, strychnine, are the same and follow the same demands as in mitral disease. When venous engorgement demands prompt relief, drastic cathartics or the abstraction of a few ounces of blood from the arm will temporarily diminish the high venous tension. The treatment of the dropsy and the local oedema is the same as for similar condition occurring in mitral disease. There are many subsidiary remedies which will have to be employed for the relief of gastric, hepatic, and intestinal symptoms, which are often the most troublesome occurrences of this disease.

{687}

CYANOSIS AND CONGENITAL ANOMALIES OF THE HEART AND GREAT VESSELS.

BY MORRIS LONGSTRETH, M.D.

The questions involved in the subject of the congenital defects of the heart and its great vessels and their causes are not easy of settlement. In the first place, the seat, the extent, and the consequences of the deficiency or defect are not regular or constant. Secondly, the causes and the mode and date of their origin are involved in great obscurity. Their classification either on a purely topographical or on a purely etiological basis is almost impossible on the one hand, because the changes are so irregular and varying, and, on the other hand, because our knowledge of the primary cause or causes of the alterations is quite defective. The views which at the present time find most favor arrange the various malformations into classes according to the period of development of the foetus at which the arrest or change of tissue occurred--as it were, a chronological classification. The ideas in respect to the pathology or the pathological causes of malformed hearts have undergone great changes--changing in some degree pari passu with the mode of classification, and in great degree inducing and compelling such changes.

In early times deformed hearts were looked upon as monsters, curiosities, lusus naturæ. When a knowledge of foetal development and circulation was acquired the deformed heart was compared with the heart-formation in classes of a lower grade than mammals. Such were the beliefs of comparative anatomy and physiology that it was held that the human foetus was matured by stages from the forms found in the lowest invertebrates through the various ascending scales of the animal kingdom. This classification was, on the basis of comparative anatomy, purely anatomical. The underlying thought of such pathological teaching was that in the original ovum something was left out--an actual deficiency of parts which, when developed in the natural manner, made man different from the lower animals; or else, supposing these parts to have been originally present, there was a defect of plasticity, causing a failure of the proper adhesion of symmetrical portions. Excessive development was looked upon as a surplus of parts in the ovum, and by their growth certain of the openings of the heart were prematurely closed. In this view of the pathological alterations no expression of opinion was made how the excess or deficiency of structure was occasioned: the malformation was merely a failure of the parts to rise and pass through the various grades of development--a too rapid or a too slow growth of one or more of the various parts of the foetal heart. There was no reason assigned why the human ovum had in it deficiencies or excesses of material, and thus came to resemble in one of its parts the conditions found in lower animals.

About 1850, Dittrich of Erlangen, by his studies of inflammation of the heart during intra-uterine life, quite diverted public opinion from the older views of the subject. Peacock's earlier studies preceded this work by a few {688} years, and a few years later came Meyer,[1] who greatly extended the scope and influence of the inflammatory theory of Dittrich. Ten years later commenced the clinical recognition of congenital heart defects, and especially the anatomical changes in congenital narrowing of the pulmonary artery, by Von Dusch and by Mannkopff,[2] and by Stoelker.[3] Friedberg had, however, as early as 1844, published his studies of the stages of development of the circulatory organs in the human embryo, and had in accordance therewith divided the malformation of the heart into three groups, corresponding to the three periods of the heart's growth. This was the classification adopted quite independently by Peacock of London in his first publication in 1857. It was not until after Dittrich's studies[4] and Meyer's that any distinctive cause was assigned for the failure to develop.

[Footnote 1: _Virch. Arch._, Bd. xii., 1857.]

[Footnote 2: _Ann. des Charité-Krankenh. zu Berl._, 1863.]

[Footnote 3: _Diss._, Bern, 1865.]

[Footnote 4: See Dorsch's (his student) dissertation, _Die Herzmuskelentzundung als Ursache angeborner Herzcyanose_, Erlangen, 1855.]

Carl Heine,[5] and also Halbertsma, proposed a classification based on the quantitative and qualitative differences. Under the first division the former placed such changes as absence of the heart, deficiency of individual parts, abnormal smallness, atresia, and fissures; and, in the other direction, duplication of the heart as a whole or in its individual parts, and abnormal largeness. The qualitative differences were deviations of form, of position, and of the arrangement of the great vessels.

[Footnote 5: _Angeborene Atresie d. Ostium arteriosum dextrum, Beitrag z. Lehre v. d. angeborenen Herzanomalium_, Tübingen, 1861.]

Peacock's classification in his earlier edition (1858) was partly on the basis of the time at which arrest of development occurs, and partly on the degree of impediment to the circulation and the functions of the heart. In his second edition he adheres to the same classes, with slight modifications, thus: 1. Arrest of development early in foetal life (fourth to sixth week; heart with two or three cavities; single or imperfectly divided arterial trunk); 2. Arrests at a later period (sixth to twelfth week; imperfect auricular or ventricular septa; imperfect or misplaced vessels); 3. Those after the third foetal month (closure and patency of foetal passages; irregularities of valves, cavities, etc.).

Kussmaul (1865) published a very important work on malformations due to defects of the pulmonary artery,[6] and these malformations he considers under two general groups--viz. those having their origin before the ventricular septum closes, and those occurring after this period. His most valuable contribution to the subject is the importance which attaches to the distinction between primary and secondary defects or arrests of development--_i.e._ between an original alteration of growth or morbid condition, and those which follow from it as a necessary consequence. Of his classification, and of the importance of pulmonary artery malformations, a further description will be given.

[Footnote 6: _Ueber angeborene Enge und Verschluss der Lungenarterienbahn_, Freiburg, i. B.]

For study, one would wish to arrange the malformations in classes convenient for clinical purposes. For example, separate them into groups of the defects compatible with extra-uterine existence and those incompatible with adult life. Unfortunately, this division is not possible. We find many cases of defects involving originally the same seat: in one the individual lives many years, in another the obstruction immediately induces symptoms, and death soon comes. A classification according to the seat of the disease alone, if it could be made, would give the subject a simplicity equal to that of valvular heart disease in the adult. Here, however, we find such variations in the details of the alteration that if this principle of classification alone is {689} employed the confusion becomes very great. It would seem, therefore, that the principle first made use of by Kussmaul, of classifying the defects by distinguishing the primary malformations from their secondary effects, renders the subject the most simple, and at the same time affords the advantage of more readily understanding the mechanism of their production.

It will be useful to pass over seriatim, following the course of the foetal circulation, the various valves, orifices, and foetal openings to be able to comprehend which are most liable to defects or to see which defects most frequently occur, and also to find which alterations produce the greatest disturbance of the circulation.

1. The Foramen Ovale and Septum of the Auricles.--In markedly deformed hearts the entire septum may be in greater or less degree wanting, as seen in cases of the bilocular or trilocular organ. This defect is comparatively rare, and the foetus has but a short extra-uterine life. In other cases the septum is complete, but the foramen may be unusually large, and remain unclosed wholly or in part; perforations may be present, or the valve may merely fail to adhere. Of the latter cases, the patent foramen is found in conjunction with defects at other parts, while small sieve-like perforations or the mere non-adherence of the membrane--both of very common occurrence--may be owing to a temporary obstruction during the early hours of life or to any unknown cause, or may possibly be due to a reopening of the foramen from an acquired disturbance of the circulation. Opinions vary as to the mechanism of the closure of the foramen. Some consider it a passive process due to increased blood-pressure in the left auricle, coming from the entrance of the current of aërated blood from the lungs; others speak of it as an active process resulting from the excitation to contraction of the muscular fibres in the membranous valve. Whatever may be the mechanism, patency of the foramen ovale of undoubted foetal origin (excepting the minute perforations and oblique slits) must be looked upon in nearly every case as a secondary defect--secondary to an obstruction to the outflow of blood from the ventricles through the great arterial trunks, or it may be from the auricle itself through defect of the auriculo-ventricular orifice. In a vastly preponderating number of cases it results from pulmonary artery obstruction. The foramen may close, however, in such a case if an outlet is provided by the aorta through an open septum ventriculorum, or when this vessel arises from both ventricles. Narrowing or closure of the right auriculo-ventricular orifice, as a primary cause, can prevent the closure of the foramen ovale; primary narrowing of the tricuspid orifice is very rare, single or combined with other defects. In these cases the direction of the blood is from the right auricle to the left. There are, however, cases on record of patency of the foramen ovale in which the blood-current is from the left to right side, the reverse of the foetal course. Here the cause to be looked to is a congenital deficiency of the mitral orifice, or a narrowing, closure, or malposition of the aorta.

2. The Right Auriculo-ventricular Orifice and Tricuspid Valve.--A primary deficiency of this orifice and the valve guarding it very rarely occurs as a primary defect and uncombined with malformation of other parts of the pulmonary circulation. It does come in certain cases in conjunction with great narrowing of the pulmonary orifice or artery, but by no means commonly. If the pulmonary outlet is normal and in the usual position, the right auriculo-ventricular orifice is never found closed, although the leaflets have been seen defective, permitting regurgitation. In certain other cases the orifice and valve, as well as entire right ventricle, show a failure to develop, and all these parts appear shrivelled. This condition is a secondary result, due to a great deficiency of the pulmonary artery and narrowing of the pulmonary conus. The malformation of the pulmonary artery in such cases results from an unequal division of the truncus communis--the narrowing {690} of the conus generally from endo-myocarditis. The aorta is unusually large in diameter. The blood from the right auricle passes through the foramen ovale to the left side of the heart; the ductus arteriosus Botalli remains open, or in very rare cases the mixed venous blood reaches the lung through collateral channels. In rare cases the blood, in addition to the open foramen ovale, has a direct passage from the right auricle into the left ventricle.

3. The Pulmonary Artery and the Right Conus Arteriosus.--This situation presents by far the largest number of cases of congenital heart malformation of primary occurrence. The defects at this part require different interpretations according as they are found within the right ventricle or in the pulmonary artery itself. So frequent are the defects at these seats that Kussmaul bases his classification, for a large proportion of cases, on the malformation of the pulmonary artery track, and describes them as combined with defects secondarily resulting in other parts.

The narrowing or closure may exist either at the limit between the sinus and the conus of the right ventricle, the conus arteriosus may be uniformly narrowed, or the defective development may involve the orifice only or the whole length of the pulmonary artery. Many of these defects, resulting in closure or narrowing, are due, as Rokitansky was the first to show, to inflammatory changes. It is Kussmaul's great merit to have pointed to the fact that a very large proportion of all malformations owe their origin primarily to diseased conditions originating at this seat. The varieties of these defects and their secondary consequents will be described later.

4. Patency of the Septum Ventriculorum.--The degree of deficiency of the septum varies greatly. The entire partition between the ventricles may be wanting or exist in merely a rudimentary condition. Ordinarily, there is found a triangular, rounded, or oval opening in the septum close to the base of the heart, at the portion which in the normal heart consists of only a membrane (pars membranacea). Besides this usual opening, one, or even two, others may present themselves at other points of the septum, thus forming multiple communications between the cavities. In narrowing or closure of the pulmonary passage the septum is more or less deflected toward the left ventricle to allow a freer passage of blood from the right side of the heart through the open septum into the aorta. In other cases the passage of blood may be from the left ventricle into the right--the reverse of the usual direction. The defects of the septum are usually of a secondary character, dependent on primary malformation of other parts, and, as already said, chiefly those of the pulmonary track. They are of congenital origin, commencing early in foetal life, before the third month, when normally the septum closes. Hence patency of this septum furnishes in many cases a valuable means of determining the date of the primary defects with which it is found combined. This malformation, however, does very rarely stand as an isolated defect, and still more rarely it is believed to have been acquired through an ulcerative destruction (myocarditis) of a portion of the septum, either during foetal or extra-uterine life; wasting or atrophy of the membranous part is sometimes thought to have occurred. In these latter cases a misdirection of the blood-current of a marked sort rarely occurs unless the inflammatory or other changes affect the main arterial orifices.

5. The aortic and mitral orifices are very much less frequently found narrowed or obstructed as the result of congenital primary defects than the orifices and their valvular apparatus of the right heart; and, also following the rule which obtains on the right side, the mitral is less frequently affected than the aortic orifice.

6. Of the Malformations of the Great Vessels.--Such changes may come alone, though usually they are combined with simultaneous or consecutive defects in other parts of the central circulatory apparatus. Of the sorts of {691} defects or malformation which these two vessels suffer, there are two chief forms to be described: 1, such as result from an unequal division of the vessels in their formation from the truncus communis; 2, those which result in more or less complete transposition of their origins. Of the transpositions we may find two sorts: in one the vessels maintain nearly their normal relative positions to each other, but each communicates with the improper ventricle; in the other they are transposed relatively to each other and also to the respective ventricles. In the first of these classes, unequal division, one variety may be ascribed to a defective or irregular development of the septum by which the vessels are formed of unequal sizes; the other, originating later in foetal life--_i.e._ after the third month (for the septum between the vessels is completed nearly simultaneously to the ventricular septum)--results from inflammatory or other morbid change in or about the orifice and trunk of one or other vessel, causing a narrowing or closure, the other vessel showing compensatory enlargement. This form is not a true unequal division of vessels. The apparent origin of one or both vessels from the same ventricle in these cases is not a true example of transposition of the vessel, but is due to a deviation of the septum ventriculorum toward one side or the other from increased blood in the ventricle from which the outflow is more or less completely obstructed. True transpositions of the vessels, both relatively to each other as well as to the ventricles, originate very early in foetal life, and these as well as the unequally-divided vessels are primary defects, and are usually accompanied by many secondary changes. Another malformation occasionally found, involving the beginning portion of the great vessels, is a failure of complete division: the septum truncus communis remains rudimentary, and the blood of the aorta is free to mingle with that in the pulmonary artery. This defect may be accompanied with a rudimentary septum ventriculorum.

7. Ductus Arteriosus Botalli.--This foetal orifice varies greatly in the conditions which are presented; sometimes it is entirely wanting, in others patulous and even in a state of dilatation; in others, again, a short portion is patent (this state is probably comparable to failure to adhere seen in the valve of the foramen ovale or the sieve-like opening in the fossa ovalis; unlike the valve of the foramen, the ductus probably never reopens), or in yet others the ductus is closed in some cases of malformation, and in others of very similar character it remains open. It becomes difficult to explain the varied states of the duct, so dissimilar are they to other defects of development present. In none of the conditions which are presented can the malformations be regarded as of a primary character. Our surprise at certain of its conditions probably must depend on a failure to justly appreciate the primary malformation present, or else on changes in the heart and the circulation coming at a period subsequent to the date of origin of the malformation of the duct itself. When the duct is open at one end and closed at the other, the open part communicates usually with the pulmonary artery, since the closing process commences normally at the aortic extremity: the closure beginning at the pulmonic extremity is occasionally seen in malformations of heart where the blood-current has had a reverse direction through the duct.

The premature closure of the ductus arteriosus Botalli, which is spoken of by some authors, seems to be a rather unfair designation to apply to the condition. In most cases it is in reality an absence of the duct dependent on the defective development of certain of the branchial arches. In other cases the apparent premature closure is due to general uniform narrowing, almost closure, of the pulmonary orifice and vessels; in such cases the lungs are supplied by the enlarged bronchial arteries or other collateral branches. The ductus arteriosus Botalli remains patulous when the pulmonary artery is {692} narrowed or closed; in these cases the blood from the right side of the heart to reach the lungs must pass either through an opening in the septum ventriculorum or through the patent foramen ovale. The duct is generally open in cases of transposition of the main arteries, or even in cases of obstruction of the aortic orifice, or of uniform narrowing of the descending aorta or its main branches. Its usual length and its point of origin from the pulmonary artery or its branches, as well as its junction with the aorta, may vary. Two ducts have been found--one from each pulmonary branch, one of them joining the aorta as usual, the other seeking one of its branches. A distinct duct has been found arising directly from the right ventricle. None of these defects are to be considered as primary malformation, but as the secondary results from alterations of the circulation occasioned by other malformations of the heart or of its great vascular trunks.

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Fully bearing in mind the distinction which must be made between primary and secondary defects, and the fact that congenital lesions of the orifices and valves are mostly located on the right side of the heart, let us look at various causes which are capable of producing malformations. In many cases, from the condition of the parts, it is possible to say positively that the alterations are dependent on an inflammatory process commencing in the endo-myocardium at an early period of foetal existence; this is true even after excluding cases in which the inflammatory products present may fairly be considered to be the result of defective development and not its cause. Inflammation was, as has already been shown, long ago pointed out as the cause of these obstructive malformations. Rokitansky (1844) was followed in his views by many, who asserted, probably wrongly, that this condition was the sole cause of the misdirection of development. It was considered that while in very many cases the evidences of the inflammation remained indubitable, in others, through a greater lapse of time, the inflammatory products became less distinct or were wholly removed. Thus, all defects of development may be traced as the results of some obstruction of the pathways of the foetal blood, which, on the one hand, effects the closure of certain vessels or orifices, or on the other hand maintains patent others which normally should be obliterated. It is much easier to trace these causes when they operate during the later periods of development, after the heart and great vessels have assumed the general shape they maintain, than those which operate at the earlier periods of transition. It is plain to us that an obstruction of the pulmonary artery or its branches coming before the end of the third foetal month must, by preventing the flow of blood through it from the right ventricle, maintain an opening of greater or less size in the incomplete septum ventriculorum. It is much less easy--or, in fact, impossible--to be positive about an obstruction or other change which causes the transposition or an unequal division of the great vessels, or which prevents entirely the development of either septum. Nevertheless, we can believe that some obstruction of the foetal circulation causes the former defect as well as the latter, if we may judge of so dark a question by the analogies. In fact, what would present itself as a trifling obstacle in the third or fourth month of foetal life would in the sixth week be an impassable obstruction.

It has been urged against the view that some inflammatory process is the invariable cause of the obstacle, by those who support the development theory, that, as the heart remains in a rudimentary condition, the defects result from a want of formative or plastive activity of the parts. It seems, however, as difficult to account for the want of formative activity which prevents the development of the septum or causes an unequal division of great arterial trunks as to find the traces of an obstruction. Maternal impressions or shocks have doubtless caused many headless {693} foetuses or otherwise misshapen the product of conception during the early months of development. The effect on the foetus from such shocks cannot of course be a direct nervous impression, such as those seen producing local disturbances of nutrition or of formative activity in the adult's own organism, but it is due to disturbances of the placental circulation, by which the blood-current is delayed in the foetal circuit. Such delay may result in a temporary obstruction of the blood in certain foetal vessels. A delay of the blood-current during a few hours in the early period of development of the foetus, when formation is excessively rapid, may result in changes which become permanent. The evidences of such obstruction may fade completely. Osler[7] has recently urged that it is difficult to suppose an endocarditis limited to the pulmonary valves in an embryo not more than an inch in length, and whose heart could not be above a few millimeters in size. But is it not possible to suppose an endocardial inflammation which affects at the same time, for example, the vascular orifices and the line of the rudimentary septum? The septum may thus be prevented from further development, and the orifice suffer malformation by subsequent contraction. The evidences of the inflammation would greatly lessen as the size of the heart expanded. Cannot inflammation, syphilis, or other communicable disease, from which we know the foetus suffers, be substituted for the unknown "want of formative activity"? In respect to the extent of surface involved in the foetal heart in inflammatory or other morbid processes, can we not suppose that the area exhibiting evidences of disease in the minute heart would be as restricted as in the adult heart? In rheumatic endocarditis of the adult the cause which leads to the inflammation is a general one; the evidences we find of the morbid process, however, are confined to very narrow limits. The reasons for this restriction may be the same.

[Footnote 7: _Montreal Gen. Hos. Reps._, vol. ii.]

The simple narrowing of a blood-track where direct evidence is wanting may be explained by the occurrence of a specific morbid process as satisfactorily as by an appeal to lack or excess of formative power. The real difficulty arises in the explanation of cases of transposition of the great vessels. The problem is in every way a most difficult one for solution under any supposition. If it were true that the formation of the pulmonary artery and the aorta was from the start by separate blood-channels, and these distinct vessels suffered a genuine transplantation and became attached to the wrong ventricle, the aorta to the right and the pulmonary to the left ventricle, then undoubtedly we should be compelled to accept the developmental theory as usually expressed. But it is not the case that these vessels are developed in distinct trunks: their development results from the division of a common trunk through an infolding of the walls or the gradual formation of a septum proceeding contemporaneously with the septum of the ventricles, the vessels at the same time making a half turn on their axis. A delay in the formation of either septum may result in the malapposition of the vessels to the ventricles. The septum which is probably delayed in formation is the vascular septum, since it is apparently the growth of this septum that applies the force which results in the axis rotation of the vessels. Are we again to explain the abortive formation of the vascular septum or any portion of the branchial arches by the unknown want of formative power? The want of formative power must have a cause; it does not come spontaneously. Are not inflammatory endarteritis and syphilitic lesions of the blood-channels probable causes of the contraction or obliteration of portions of the branchial arches?

Another question, dark and obscure, requires a short comment. It is commonly accepted, if an abnormal communication (speaking of small openings) exists between the two ventricles, that the septum has been prevented from {694} closing by the blood-current being diverted from its usual course through narrowing of an arterial ostium, and compelled to flow into one or the other ventricle. The patency or the closure of the ventricular septum is held as a criterion of the date of origin of the primary malformation. We know that certain ulcerations of the endo-myocardium may result in forming openings between the two ventricles, but is it not possible that a perforation may be made in the ventricular septum after it has closed by a lesion originating at an arterial ostium of the same character as one that prevented the septum from closing? The muscular tissue of the heart from the third to the sixth foetal month, and even later, is of very soft character. A rapidly-coming closure, or even temporary obstruction, of one or the other great arterial trunks would greatly increase the blood-pressure within the corresponding ventricular cavity. The ventricular septum would become stretched and thin, and might readily be perforated, so delicate is the muscular tissue.