Clinical analysis of five infants with glycogen storage disease of the heart--Pompe's disease.

Five cases of infant glycogen storage disease of the heart are reported. Their ages ranged from 2 to 7 months. They all presented with generalized hypotonia and respiratory tract infections. Four of the diagnosis were proven by skeletal muscle biopsy and enzymatic assay of alpha-1,4-glucosidase. All 5 infants had clinical signs of cardiac failure, cardiomegaly shown by chest X-ray, short PR intervals, severe left or bi-ventricular hypertrophy shown on electrocardiograms, increased thickness of the right and left ventricular walls and interventricular septum both on M-mode and two-dimensional echocardiograms and angiocardiograms. Four of them died during the follow-up period with a mean age at death of 7.5 months.