Degenerations of the Myocardium.
Anemic necrosis, anemic infarct, or white infarct, is the term given to that form of myocardiac degeneration due to occlusion of the branches of the coronary artery. As the anterior coronary artery is most frequently the seat of the obstruction, the infarcts are most frequently found in the left ventricle and septum, parts supplied by this branch of the artery, and consist of patches of grayish white or grayish red, wedge-shaped masses. These may become softened and break down, forming what is known as myo-malacia cordis. This softened, and therefore weakened area, may cause a rupture of the heart.
At other times these spots, in place of softening, change to a hyalin appearance, which in turn become sclerotic. The minute changes in the muscular tissue are the replacement of the muscle .fibers with granular material. At other times they assume a hyalin form, and finally become sclerotic.
The symptoms are obscure, unreliable, and of no diagnostic value. Death may occur suddenly, and an autopsy alone reveal the lesion.
Calcareous degeneration, or calcification of the myocardium, is of very rare occurrence, and consists of the displacement of the muscular fiber by limy deposits.
Calcification of the valves occurs more frequently. Following myocardial abscesses, chalky nodules may sometimes be found.
Amyloid Degeneration.—This, like calcification, is a rare disease, and results from the same causes that give rise to amyloid disease of any other part. It is more apt to be confined to the blood-vessels and interstitial tissues, and is frequently preceded by suppurative processes, tuberculosis, syphilis, etc.
Hyalin Degeneration.—This has already been noticed in connection with anemic necrosis, and may also be found in connection with amyloid degeneration. The connective tissue is replaced in limited areas by a glossy, transparent material.
It may occur independently of other degenerations and follows prolonged suppurative fevers. The fibers become swollen, and are changed into a homogeneous translucent material.
Brown Atrophy.—This is a form of degeneration that is frequently found in connection with other degenerations, especially fatty, and consists of a deposit in the muscular tissue of a yellowish-brown, granular material. It is found in advanced valvular troubles sometimes, and.in old people.
The diagnosis is made post-mortem.
Parenchymatous Degeneration has been considered in chronic myocarditis.
Fatty Degeneration.—This is not to be confused with fatty infiltration or fatty overgrowth. Fatty degeneration is the replacement of the muscle fiber by oil globules or fat. This is perhaps the most common of all degenerations and is due to faulty nutrition. This may arise from many conditions. We may say that all wasting diseases, such as tuberculosis, carcinoma, acute and chronic anemia, and the various infectious diseases, are causal conditions.
Syphilis, by its poisoning effect, may change the nutritive properties of the blood to such an extent as to render the fiber unable to reproduce itself. Pericarditis and the valvular lesions, which have already been considered, also favor this condition. Disease of the coronary arteries, by impairing nutrition, is a frequent cause. It is also associated with other degenerations, parenchymatous, white, infarct, etc. The disease is more frequently met with after middle life, and is more common in men than in women.
Certain poisons, such as phosphorus, arsenic, and alcohol, are followed by fatty degeneration. When due to phosphorus or arsenic, the degeneration is sometimes quite rapid, while if from alcohol it involves a much longer time.
Pathology.—The degeneration may be confined to local areas or the entire organ may be involved. Usually the left ventricle and papillary muscles are the seat of the tissue change. Yellowish patches are seen, which are friable and easily torn. Sometimes it is of a reddish-brown color, and frequently occurs with brown atrophy. Its friability favors rupture of the organ, which sometimes occurs. If the entire organ be involved, there is enlargement, its walls being flabby.
Fatty degeneration of the heart is not infrequently associated with fatty degeneration of other parts of the body. As a result of its friability, dilatation of its cavities is not uncommon. Sclerosis of the coronary arteries is often found.
Symptoms.—The symptoms of this form of degeneration are not characteristic and may not be separated from myocarditis. Enfeeblement is always a prominent condition, and palpitation, dyspnea, and a quick, feeble, and irregular pulse, with cool, clammy extremities, are symptoms that would arouse suspicion of the true condition.
Cardiac asthma, with occasional attacks of angina pectoris, may also be present.
Physical signs are similar to those of cardiac dilatation.
Diagnosis.—The diagnosis is extremely difficult. The age of the patient, the enfeebled action, the small, irregular pulse, the evidence of dilatation, the dyspnea and palpitation, cardiac asthma and angina pectoris, and, in advanced stages, the Cheyne-Stokes respiration, would all suggest fatty degeneration, though a positive diagnosis should not be made.
Prognosis.—The prognosis is unfavorable as to a cure, though the patient may live for years after tissue changes have taken place. Undue exertion, or great mental excitement may result in rupture of the heart, and sudden death.
Treatment.—If one keeps in mind the conditions that give rise to degenerations, the line of treatment will suggest itself. Impaired nutrition, enfeebled vitality, and cell formation prevent normal tissue formation. To make a good blood, to renew the tissue, and to break down the old and imperfect tissue, is a difficult task, and one that many times is impossible to accomplish.
Hygienic measures are important. An equable climate, an out-of-door life, gentle exercise, regular habits, and the avoidance of severe exertion or mental excitement, will do much for the patient. A nutritious but easily digested diet, with a restriction of fluids, especially at meal-times, will assist largely in maintaining the health, and further stay tissue change.
Cactus, pulsatilla, crataegus, lobelia, etc., will be used as occasion demands.
The Eclectic Practice of Medicine, 1907, was written by Rolla L. Thomas, M. S., M. D.