Overview

Myocarditis is an inflammation of the heart muscle (myocardium). The inflammation can reduce your heart's ability to pump and cause rapid or abnormal heart rhythms (arrhythmias).

Infection with a virus usually causes myocarditis. Sometimes myocarditis can result from a reaction to a drug or be part of a more general inflammatory condition. Signs and symptoms include chest pain, fatigue, shortness of breath, and rapid or irregular heartbeats.

Severe myocarditis weakens your heart so that the rest of your body doesn't get enough blood. Clots can form in your heart, leading to a stroke or heart attack.

Treatment for myocarditis depends on the cause.