Myocarditis is an inflammation of the heart’s muscular wall, the myocardium. Although rare, it can be devastating. Myocarditis can occur with no symptoms and remain undiagnosed.
Many cases of myocarditis have no identifiable cause. This is called idiopathic myocarditis. When a cause is identified, it falls into one of 3 categories:
Some people have no symptoms of myocarditis. In those that have them, symptoms can vary from person-to-person depending on the cause and the severity. Symptoms may appear slowly or come on suddenly.
Sudden, intense myocarditis can lead to heart failure.
The diagnosis of myocarditis is often difficult. There is no specific test for it. Many other causes of heart problems must be ruled out. To do this, your doctor will ask about your symptoms and medical history. A physical exam will be done.
Tests may include:
Imaging tests evaluate the heart and surrounding structures:
The universally recommended therapy for myocarditis is bedrest, no physical activity, and supplemental oxygen. Corticosteroids may be given to help inflammation. You will most likely be admitted to a hospital.
Specific treatment is directed at the underlying cause if possible. For instance:
If heart failure symptoms are present, medications are given to support the function of the heart. These include diuretics, angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, and anti-arrhythmic agents.
Additionally, a defibrillator, which helps maintain the normal rhythm of the heart, may be implanted into your chest. Severe cases may require a cardiac transplant.
To help reduce your chance of myocarditis, reduce your exposure to identified causes:
American Heart Association
National Heart, Lung, and Blood Institute
Canadian Cardiovascular Society
Drory Y, Turetz Y, et al. Sudden unexpected death in persons less than 40 years of age. Am J Cardiol. 1991;68:1388-1392.
Felker GM, Thompson R, et al. Underlying causes and long-term survival in patients with initially unexplained cardiomyopathy. N Engl J Med. 2000;342:1077-1084.
Brady WJ, Ferguson JD, et al. Myocarditis: Emergency department recognition and management. Emergency Medicine Clinics of North America. 2004;22(4):865-885.
Feldman AM, McNamara D. Myocarditis. N Engl J Med. 2000;343(19):1388-1398.
Myocarditis. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T114167/Myocarditis. Updated December 8, 2015. Accessed September 29, 2016.
Understand your risk of heart failure. American Heart Association website. Available at: http://www.heart.org/HEARTORG/Conditions/HeartFailure/UnderstandYourRiskforHeartFailure/Understand-Your-Risk-for-Heart-Failure_UCM_002046_Article.jsp. Updated October 24, 2014. Accessed December 30, 2014.
Last reviewed December 2015 by Michael J. Fucci, DO
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.