Definition.—Cardiac atrophy is a decrease in the size, strength, weight, and activity of the heart.
Etiology.—The causes depend somewhat upon the character of the atrophy, whether general or local. Thus mitral stenosis gives rise to a local atrophy, the left ventricle being the part affected. Other parts may atrophy when degenerative changes are confined to a portion of the heart, while general cardiac atrophy may arise from causes that impair or interfere with the nutrition of the body, the heart sharing in the general atrophy, cancer of the stomach, phthisis pulmonalis, suppurative processes where long continued, Bright's disease, etc., being examples. Partial obstruction of the coronary arteries may give rise to atrophy by impairing the heart's nutrition. Senile atrophy is usually the result of failing nutrition. General atrophy may also be congenital.
Pathology.—The degree of atrophy varies, Bramwell reporting a case in an adult where the heart weighed only two and three-fourths ounces. The surface of the heart loses its regular outline, becoming wrinkled or rough, while the coronary arteries are quite tortuous. As the waste exceeds the supply, the sub-pericardial fat early disappears, and may be replaced by a granular or mucous tissue.
The color varies: it may be pale and firm, or it may be yellow and known as yellow atrophy: again it may be pigmented, soft, and granular, and known as brown atrophy. The muscular fibers may be replaced in part by granular or fatty material.
Symptoms.—The symptoms of cardiac atrophy are not very pronounced, feebleness of action being the most prominent; but as this is characteristic of all wasting diseases, we may not gain much information from this source. The apex-beat is quite weak and often invisible, and, though percussion shows the area of dullness diminished, it may be due to pulmonary emphysema.
Diagnosis.—While atrophy may be suspected, a positive diagnosis is only made post-mortem.
Prognosis.—The prognosis depends more upon the underlying disease than upon the extent of the atrophy of the heart; for, though diminished in size, there is diminished work required, and a proper balance is maintained.
Treatment.—The treatment will be tonic and restorative. Where the primary lesion can be overcome, our treatment will be directed to the accomplishment of that end. Gentle exercise in the open air, a good, nutritious, and easily digested food supplied, will be an important factor in the treatment. All measures that look to a better blood supply will aid in prolonging life. Incidentally cactus or crataegus may be given as heart tonics.