Cardiac Myopathy, Probably of Congenital Origin

The clinical and pathologic findings are presented in a 1-year-old child with an unusual cardiac myopathy of the left ventricle.[see figure in the PDF file][see figure in the PDF file]The clinical findings suggested the diagnosis of anomalous origin of the left coronary artery from the pulmonary trunk. These features included insidious onset of cardiac failure in the first year of life, massive cardiomegaly with nearly normal pulmonary vasculature, absence of cyanosis and of a cardiac murmur, and electrocardiographic and vectorcardiographic findings of left ventricular hypertrophy with severe myocardial ischemia or infarction.[see figure in the PDF file]Angiocardiograph studies, which did not support this diagnosis, revealed an aneurysmally dilated left ventricle with unusual internal septations and loculations.The necropsy showed concentric semicircular muscular ridges and grooves in the apical portion of the left ventricle and a peculiar fibrous endocardial network of the same chamber. It is suggested that this process may be congenital in origin.