Cardiac Involvement in Sporadic Inclusion-Body Myositis

Abstract

A 36-year-old man came to the emergency department with acute onset of exertional chest pain. He had had no recent infections, and no cardiovascular risk factors were present. However, the patient had used a wheelchair since his mid-20s because of sporadic inclusion-body myositis, as established by muscle biopsy. There were no other physical findings. Inflammatory markers and troponin T were normal, and the creatine kinase was elevated 2-fold with a significant muscle brain fraction. Chest roentgenogram was normal, but ECG showed a normal sinus rhythm at 62 bpm with deep Q waves, tall R waves in the right precordial leads, interventricular conduction delay, and T wave inversion in the left lateral leads (Figure 1). Echocardiography did not reveal any abnormalities. Cardiovascular magnetic resonance (CMR) examination was next performed. Figure 1. Twelve-lead electrocardiogram demonstrating deep Q waves, tall R waves in the right precordial leads, interventricular conduction delay, and T inversion in the left lateral leads. Two-chamber (Movie I of the …