The natural history of hypertrophic cardiomyopathy in infants of diabetic mothers.

Eleven infants of diabetic mothers with hypertrophic cardiomyopathy have been followed for 30 to 40 months. All infants presented with cardiorespiratory distress and were found to have disproportionate septal hypertrophy on echocardiogram. Cardiac catheterization was done in four infants; three had significant subaortic obstruction. One infant had remarkable improvement after treatment with propranolol. Two infants who received digoxin did poorly and responded favorably to cessation of therapy. The natural history of HCM-IDM appears to be benign, with a resolution of symptoms within two to four weeks and a resolution of septal hypertrophy within two to 12 months. Most of the infants need only supportive care; if pharmacologic intervention is deemed necessary, propranolol appears to be the drug of choice. The natural history of this entity is that of spontaneous regression of symptoms and septal hypertrophy irrespective of therapy.