When myocarditis is severe, it can permanently damage your heart muscle. This damage might cause:

  • Heart failure. Left untreated, myocarditis can damage your heart's muscle to the point it can no longer pump blood effectively, causing heart failure. In severe cases, myocarditis-related heart failure may require a ventricular assist device or a heart transplant.
  • Heart attack or stroke. If your heart's muscle is injured and can't pump blood, the blood that pools in your heart can form clots. If a clot blocks one of your heart's arteries, you can have a heart attack. If a blood clot in your heart travels to an artery leading to your brain before becoming lodged, you can have a stroke.
  • Irregular heart rhythms (arrhythmias). Damage to your heart muscle can cause irregular heart rhythms (arrhythmias).
  • Sudden death. If your heart muscle is damaged, you may develop serious arrhythmias. It's possible certain serious arrhythmias could cause your heart to suddenly stop beating (sudden cardiac arrest). If not treated immediately, it causes sudden cardiac death.
Oct. 24, 2015