Inflammation of the heart muscle.

Myocarditis is a heart condition commonly caused by a viral infection. But bacteria, parasites and fungal infections can cause it too. Some medicines and exposure to chemicals or radiation may cause to myocarditis. Myocarditis makes it hard for the heart to pump blood. Severe myocarditis can weaken the heart and cause heart failure.

Symptoms include chest pain, shortness of breath, feeling very tired, and rapid and irregular heartbeats. The feet and ankles may become swollen. Some people also have flu-like symptoms.

Treatment may include rest and medicines. Some people need surgery or a procedure to place a medical device to help the heart work better. A heart transplant may be needed if myocarditis is severe.