Myocarditis is an inflammation of the myocardium, the middle layer of the heart wall. Myocarditis is usually caused by a viral infection. Symptoms of myocarditis include chest pain, heart failure and abnormal heart rhythms.

Severe myocarditis can weaken the pumping action of the heart impairing the heart’s ability to supply enough blood to the rest of the body. Clots can also form in the heart and cause a stroke or a heart attack.

Treatment options for myocarditis vary depending on the underlying cause.



In mild cases of myocarditis there may be no noticeable symptoms. However, in serious cases the symptoms of myocarditis can vary depending on the cause of the disease.

Common symptoms of myocarditis include:

  • Chest pain
  • Rapid or abnormal heartbeat (arrhythmia)
  • Shortness of breath
  • Fluid retention with swelling of the legs, ankles and feet
  • Fatigue
  • Headache, body aches, joint pain, fever, sore throat or diarrhea


Myocarditis in children


  • Fever
  • Fainting
  • Breathing difficulties
  • Rapid breathing
  • Bluish or grayish discoloration of the skin



Sometimes the exact cause of an individual case of myocarditis is not identified. However, there are many potential causes of myocarditis:


  • Viruses: Coxsackievirus B, adenovirus, parvovirus B19, gastrointestinal infections (echoviruses), mononucleosis (Epstein-Barr virus), rubella and HIV.
  • Bacteria: Staphylococcus, streptococcus, bacteria that causes diphtheria, Lyme disease.
  • Parasites: Trypanosoma cruzi and toxoplasma
  • Fungi: Yeast infections (candida), molds (aspergillus) and other fungi
  • Medications or illicit drugs: Penicillin, sulfonamide drugs, anti-seizure medications or illegal drugs such as cocaine
  • Other diseases: Lupus, connective tissue disorders and rare inflammatory conditions



Severe myocarditis can permanently damage the heart muscle. The damage may cause:


  • Heart failure: Damage to the heart muscle can impair the ability of the heart to pump blood effectively and cause heart failure.
  • Heart attack or stroke: A damaged heart increases the clotting factors, which increase the risk of a clot to block one of the arteries and cause a heart attack or stroke.
  • Irregular heartbeats (arrhythmias)
  • Sudden death: A severely damaged heart muscle can lead to a strong arrhythmia that causes the heart to suddenly stop beating (sudden cardiac arrest). If it is not treated immediately, it causes sudden death.



Ways to prevent infections that may lead to myocarditis:

  • Avoiding people with viral or flu-like illness
  • Maintaining a good hygiene
  • Avoiding risky behaviors such as unprotected sex or using illegal drugs
  • Minimizing exposure to ticks
  • Being up to date on recommended immunizations