Transient hypertrophic subaortic stenosis in infants of diabetic mothers.

Three newborn infants with congestive heart failure had hemodynamic, angiographic, and echocardiographic features of hypertrophic subaortic stenosis (hypertrophic obstructive cardiomyopathy). Treatment with digitalis and diuretic drugs was ineffective, but improvement occurred when these agents were withheld in one patient, and when treatment with propranolol was begun in two patients. Echocardiography was helpful in establishing the diagnosis in two patients and showed resolution of the condition during the first six months of life. Serial cardiac catheterizations confirmed resolution of the outflow obstruction in the third patient. Family studies revealed no evidence of familial cardiomyopathy, but the mothers of two infants had insulin-dependent diabetes mellitus and the mother of the third was presumed to be prediabetic.