Etiology.—The disease may follow an acute attack, the effused material not being completely absorbed, and the sticky, gluey residue becomes organized, and adhesions follow. Again the disease comes on so insidiously that it is never suspected, even though extensive adhesions have taken place, and they are only revealed during an autopsy. In the latter case, no history of an acute attack can be discovered, and the disease becomes chronic from repeated irritations, probably due to rheumatic attacks, or it' may be the result of tuberculosis or malignant growths.
Pathology.—The amount of adhesions varies, depending largely upon the character of the inflammation. In some it is very slight, while other cases present a total obliteration of the cavity, and between these extremes are every gradation of organization.
When tuberculosis or malignant growths involve the heart, the thickening is quite extreme. In the rarer case the pericardium undergoes calcification, or even ossification. This follows more often when the effusion has been purulent in character.
Drummond reported a case of extreme calcification of the heart in a sailor aged forty-three, who was able to perform his work up to a few wrecks before his death. On autopsy, it was found that the pericardial sac was nearly obliterated, and the pericardial layers were extensively calcified.
The process of calcification had extended so as to involve the heart muscles, in which had developed great bonelike plates, which had to be sawn through, and which had a thickness, in spots, of an inch. The whole posterior surface of the right ventricle was composed of a triangular chalk-plate three inches high and three and one-half inches broad at the base. A thick, bone-like mass ran across the whole left ventricle, penetrating the entire wall of the heart like a wedge, and reaching into the cavity of the left ventricle. ("Twentieth Century Practice.")
Symptoms.—The symptoms are obscure in many cases, and not sufficiently pronounced to attract attention, the disease not being suspected during life, and only revealed post-mortem while searching for other conditions. Where there is extensive thickening or calcification of' the pericardium, the circulation is more or less obstructed and attended by precordial oppression and a sense of constriction and dyspnea. The pulse is rapid, feeble, and irregular, and of low tension, known as the pulsus paradoxus.
The free movement of the heart is prevented where the adhesions are marked; hence hypertrophic dilatation of its chambers is a frequent sequence.
Physical Signs.—Since the general symptoms in many cases are insufficient to draw the attention of the physician to the patient's true condition, the attendant should make a physical examination of all of his chronic cases, especially those with a history of rheumatism, for quite definite knowledge may be thus gained.
Inspection.—As a result of the adherent pericardium, there will be a sunken or depressed condition in the intercostal spaces and over the precordial region. One of the most common as well as most valuable signs is "the systolic tug," which occurs with each pulsation and may be seen near the sternum, between the seventh and eighth interspace.
On examining the back of the patient a visible retraction of the chest will be observed between the eleventh and twelfth ribs, during each systole. This is known as Broadbent's sign.
If dilatation has not taken place, the apex-beat is visible over a much larger area than normal; but after dilatation, owing to its enfeebled condition, the apex beat can not be seen.
Palpation.—The apex beat remains in a fixed area notwithstanding a change of position. One of the most reliable physical signs is the diastolic rebound or shock following the drawing in of the anterior chest-wall during each systole. This rapid rebounding of the chest-wall may suddenly empty the jugular veins, giving rise to the diastolic collapse, or Friedreich's sign; this, however, may also occur in cardiac dilatation without adhesions.
Percussion.—In a majority of cases of pericarditis there are adhesions between the pleura and pericardium, thus preventing an overlapping of the heart by the lung; this accounts for the increased area of dullness upward and to the left; this, however, is not pathognomonic, as we have a large area of dullness where the pleura is adhered to the chest-wall, and no cardiac lesion.
Auscultation.—The sounds heard on auscultation are variable, and, on the whole, not very reliable, since similar murmurs are heard in other cardiac affections. Before dilatation takes place, no murmurs are to be heard, but with the gradual dilatation the murmurs begin, increasing in intensity with the progressive increase of the cavities.
Diagnosis.—We are to distinguish this from pericarditis with effusion, and also from simple hypertrophic dilatation. We recognize it from the former by the fixed apex beat not being influenced by change of position, by the concave or depressed precordial region, while in the latter there is convexity or bulging of the intercostal spaces. The diastolic shock or rebound is absent where there is effusion. In simple hypertrophic dilatation the murmurs are almost identical, but the apex beat is not so circumscribed and there is no depression of the interspaces.
Prognosis.—The compensatory changes that take place in hypertrophy of the heart establish a harmonious balance of forces, and the patient, if not overtaxed, is comparatively comfortable, and may live for years after there are pronounced adhesions. In course of time, however, myocardial degeneration takes place, and if this be accompanied by dilatation, a sudden termination need cause no surprise. The disease is very chronic in its character.
Treatment.—The physician is rarely ever consulted in the early stages of the disease, or the diagnosis is not made till such organic changes have taken place that a radical cure is almost out of the question, and the best the physician may hope to accomplish, is to stay further organic changes, relieve such unpleasant complications as may arise, and render the patient as comfortable as possible.
Where the patient is able to profit by such advice, we would recommend for residence a climate where the air is dry, pure, and where there is abundant sunshine and equable temperature; where the patient can live in the open air the greater part of his time with the least expenditure of vital force. He should avoid all excitement and such exercise as would prove exhausting or overtax the heart. The diet should be nutritious and easily digested.
Cactus, digitalis, crataegus, strophanthus, and like remedies, will be administered as they may be needed. Cactus, especially, will be a good remedy to continue indefinitely, three or four doses per day. Iodide of arsenic, 2x, may be given, with the possible hope that it may assist in the absorption of fibroid deposits, but too much dependence should not be placed in drugs to accomplish this end.
After dilatation becomes marked, cactus, digitalis, and strychnia will be used to support the heart's action, and the patient must be kept very quiet.