Myocardial dysfunction in polymyositis.

Myocardial involvement in polymyositis is occasionally suspected, but symptomatic cardiac dysfunction is rarely reported. Described in the present report is a 48-year-old woman with a two-year history of polymyositis who suddenly developed near fatal ventricular arrhythmia, and a 56-year-old man with a relapsing polymyositis who developed severe systolic dysfunction. These two cases emphasize the importance of systematic cardiac evaluation when the diagnosis of polymyositis is initially made and the necessity of re-evaluating cardiac function, even in the presence of clinical remission and normalization of creatine phosphokinase with treatment.