by EBSCO Medical Review Board


Myocarditis is a rare inflammation of the heart’s muscle.

Healthy Myocardium
normal heart section
Copyright © Nucleus Medical Media, Inc.


In most children, this problem is caused by a viral infection. Other causes may be:

  • Infections by bacteria, parasites, or fungus
  • Problems with the immune system, such as systemic lupus erythematosus
  • Taking certain medicines
  • Exposure to toxins, such as heavy metals

Sometimes the cause is not known.

Risk Factors

There are no known risk factors.


Some children may not have symptoms. This is common in babies and young children.

Those who do have problems may have:

  • Fever
  • Weakness and lack of energy
  • Muscle or joint pain
  • Vomiting
  • Belly pain
  • Diarrhea
  • Swelling of the face, feet, or legs
  • Urinating less than usual
  • Problems breathing
  • Fast heartbeat
  • Chest pain
  • Loss of consciousness


The doctor will ask about your child’s symptoms and health history. A physical exam will be done. It will focus on the heart. This is often enough to make the diagnosis. There is no specific test for myocarditis.

A blood test or tissue biopsy will be done to look for signs of myocarditis.

Images may be taken of your child's bodily structures. This can be done with:

The electrical activity of your child's heart may be measured. This can be done with an electrocardiogram (ECG) .


Emergency care will be needed. Any underlying cause will be treated.

The goal of treatment is to manage symptoms and promote healing. Activity will be limited. Medicines will be given, such as:

  • Antibiotics or antiviral medicine to fight infection
  • Medicine to suppress the immune system
  • IV immunoglobulin to ease inflammation

Medicine may also be given to support heart function and remove extra fluid from the lungs or other body tissues.


There are no known guidelines to prevent this health problem.


American Heart Association 

National Heart, Lung, and Blood Institute 


Canadian Cardiovascular Society 

Health Canada 


Dasgupta S, Iannucci G, et al. Myocarditis in the pediatric population: A review. Congenit Heart Dis. 2019 Sep;14(5):868-877.

Myocarditis. Children's Hospital of Philadelphia website. Available at: Accessed March 9, 2021.

Myocarditis. EBSCO DynaMed website. Available at: Accessed March 9, 2021.

Myocarditis. Seattle Children's Hospital website. Available at: Accessed March 9, 2021.

Revision Information

  • Reviewer: EBSCO Medical Review Board Kari Kassir, MD
  • Review Date: 12/2020
  • Update Date: 03/09/2021