Abstract
A 58-year-old man with a recent history of generalized myalgia and muscle weakness was transferred to our hospital because of acute progressive dyspnea. The patient underwent left ventricular (LV) assist device (LVAD) implantation due to cardiogenic shock with a LV ejection fraction (LVEF) of 6%. The histological findings obtained from LV apex showed the infiltration of multinucleated giant cells and severe myocardial contusion. Combining this histological finding with our experienced neurologists comments, resulted in a final diagnosis of fulminant giant cell myocarditis associated with polymyositis. A day after LVAD implantation, the patient received corticosteroid and immunosuppressive therapy, and the LVEF recovered to 68%.