Endomyocardial biopsy finding in two patients with idiopathic dilated cardiomyopathy receiving long-term treatment with amiodarone

Abstract

Amiodarone, a highly effective antiarrhythmic agent, accumulates in different tissues, causing a variety of adverse effects.1–3 Long-term amiodarone treatment may cause diffuse interstitial pulmonary fibrosis and inflammation, with accumulation of cytoplasmic bodies containing electron-dense lamellas in pneumyocytes and alveolar macrophages 1,2. Similar bodies have been described in liver, lymph nodes, blood leukocytes, cornea, endothelial cells of skin, colonie mucosa, 3 and Schwann cells. Such bodies also have been found in cardiac myocytes of experimental animals treated with multiple doses of this drug 4,5; however, to our knowledge, they have not been reported in the myocardium of patients treated with amiodarone. This report describes ultrastructural changes in the myocardium of 2 patients with idiopathic dilated cardiomyopathy who had received long-term amiodarone treatment.