A case of foamy myocardial transformation of infancy.

A case of infantile cardiomyopathy in a year and four months old girl, which was clinically characterized by tachycardia resistant to any drugs and marked hyperplasia of mitochondria in their cytoplasms on electron microscopic observation, was presented. In the present case light and electron microscopical proof of the diagnosis was obtained by right endomyocardial biopsy, while most of this condition has not been recognized prior to autopsy. In Japan this newly recognized infantile cardiomyopathy has not been reported, and we proposed that this condition could be designated as mitochondrial cardiomyopathy caused by unknown etiology. The literatures described previously in the world have been reviewed.