Aneurism may be confined to the valves—valvular aneurism; or may involve the walls of the myocardium—aneurism of the heart-wall.
Etiology.—Aneurism of the valve results from endocarditis, either acute or chronic, whereby the reflection of the endocardium upon the valve becomes softened or destroyed, and the intro-cardial blood-pressure produces dilatations, spherical in form, the convex side facing the least resistance. Thus, when of the aortic valve, the most frequently involved, the aneurism bulges into the left ventricle; while if the mitral valve be the one involved, the aneurism projects into the left auricle. When rupture occurs, valvular incompetency is pronounced.
Aneurism of the wall is usually due to weakening of the tissue by myocarditis, though the various degenerations, which occur in the heart, as well as mural endocarditis, may be responsible for it. Knife-wounds have also been followed by aneurism. Pericardial adhesions may so weaken the wall as to favor dilatation.
Pathology.—The dilatation, followed by sacculation, is usually found near the apex in the left ventricle. In size, they vary from that of a marble to that of a croquet-ball. There is usually only one, though this may be sacculated, forming two patches in one cavity, and Peacock reports a case where there were three pouches. The endocardium is found to be opaque, while the myocardium may undergo degeneration or sclerosis.
Symptoms.—The symptoms are not sufficiently definite to excite suspicion of the true character of the disease. There is general enfeeblement, due to the lesions that give rise to it, and sometimes a bulging, pulsating tumor may be seen in the apex region.
Diagnosis.—A positive diagnosis is only made post-mortem.
Prognosis.—The prognosis is unfavorable, and, though death may occur suddenly from syncope and rupture, it is usually due to exhaustion depending upon the myocarditis or the degenerations which give rise to it.
Treatment.—The same line of treatment as was suggested in cardiac degenerations will be followed in aneurism. Hygienic, dietetic, and such cardiac remedies as may be required to meet special conditions, will compose the treatment.
The Eclectic Practice of Medicine, 1907, was written by Rolla L. Thomas, M. S., M. D.