Abstract
BACKGROUND: Dilated cardiomyopathy (DCM) is a common cause of systolic heart failure, and is the most prevalent type of non-ischemic cardiomyopathy. Primary hyperparathyroidism (PHPT) is characterized by hypercalcemia and excessive secretion of parathyroid hormone (PTH). Generally, PHPT is asymptomatic and is incidentally identified during routine laboratory assessments. CASE SUMMARY: This case report details a 52-year-old man diagnosed with DCM and refractory hypercalcemia, who presented with clinical manifestations including dyspnea, recurrent anorexia, and abdominal distention. Laboratory investigations indicated an elevated serum PTH level, and the sestamibi scan suggested the presence of a parathyroid adenoma. Hence, the patient underwent a parathyroidectomy, which pathologically confirmed the diagnosis of a parathyroid adenoma. Postoperatively, the patient's hypercalcemia was corrected, the dimensions of the cardiac chambers were reduced, and there was a marked improvement in cardiac function. CONCLUSION: Our findings emphasize the importance of PTH assessment in patients with DCM and concurrent hypercalcemia.