Hypocalcemic cardiomyopathy due to untreated hypoparathyroidism.

Hypocalcemic cardiomyopathy due to hypoparathyroidism is a very rare condition which is usually refractory to conventional treatment for cardiac failure but which responds favorably to restoration of normocalcemia. A 55-year-old man and a 46-year-old woman with a history of postoperative hypoparathyroidism presented with symptoms of cardiac failure and hypocalcemia. A presumptive diagnosis of dilated cardiomyopathy was considered by echocardiography and endomyocardial biopsies were consistent with cardiomyopathy. The coronary angiograms were normal and there was no apparent cause for dilated cardiomyopathy in these patients. The history of the patients and partial recovery of cardiac function after restoration of normocalcemia suggest that hypocalcemia was the cause of dilated cardiomyopathy.