BACKGROUND Chronic hypocalcemia may cause electrocardiographic (ECG) changes and mimic acute myocardial infarction. It has also been associated with reversible cardiac dysfunction. On the other hand cardiomyopathy and heart failure have been reported in patients with idiopathic hypoparathyroidism or celiac disease. METHODS A 39-year-old male was admitted to the emergency room with acute retrosternal pain and dyspnea. He exhibited severe hypocalcemia and acute renal failure. High creatine kinase (CK) levels did not correlate with biomarkers of myocardial necrosis (negative troponin test, heart type creatine kinase isoenzyme (CK-MB) < 1% of CK value). The ECG showed an extremely long QT interval (0.6 sec) and T-wave inversions on V(4) through V(6). The left ventricular ejection fraction (LVEF) was as low as 25%, while coronary angiography was normal. Investigation of the hypocalcemia revealed primary hypoparathyroidism (Parathyroid hormone (PTH) < 3 pg/ml) and concomitant celiac disease with positive antigliadin and endomysial antibodies. The cardiovascular episodes and the dilated heart failure were attributed to the chronic hypocalcemia since no other cause was found. The correction of hypocalcemia has not been sufficient to reverse the end-stage heart failure after more than 6 months of treatment, even though ECG abnormalities have receded, implying permanent cardiac impairment. CONCLUSIONS This case demonstrates an unusual clinical condition where 2 calcium homeostasis disorders led to severe hypocalcemia with clinical manifestations of end-stage heart failure. The severe cardiac failure appeared to be nonreversible after calcium repletion suggesting permanent cardiac muscle dysfunction due to associated cardiomyopathy.