Inflammation of the muscle tissue of the heart, usually due to an infection

  • Age, gender, genetics, and lifestyle are not significant factors

Myocarditis is inflammation of the heart muscle, usually due to an infection Frequently, the condition goes unrecognized because there are no obvious symptoms. However, severe inflammation of the heart muscle may develop, causing chest pain and leading eventually to heart enlargement and chronic heart failure.

The most common cause of the disorder is a viral infection, usually with the coxsackie virus. Myocarditis may also be due to rheumatic fever, although this is now rare in developed countries, mainly due to the widespread use of antibiotics. Some autoimmune disorders, such as systemic lupus erythematosus, in which the body attacks its own tissues, may also cause myocarditis.

What are the symptoms?

Myocarditis often causes no symptoms. However, if symptoms do occur, they usually develop over a number of hours or days and may include:

  • Fever.

  • Tiredness.

  • Aching in the chest.

  • Palpitations (awareness of an irregular or abnormally rapid heartbeat).

Eventually, breathlessness and swelling of the ankles may develop due to heart failure. Rarely, myocarditis causes sudden death during vigorous exertion.

What might be done?

If your doctor suspects that you have myocarditis, he or she will probably arrange for an ECG to monitor the electrical activity of the heart and a chest X-ray to see if the heart is enlarged. You may have echocardiography to image the interior of the heart. Blood tests may be carried out to check for infection and for the presence of enzymes that can indicate whether or not the heart muscle is damaged.

Myocarditis is usually mild, and the heart should recover within 2 weeks. If severe heart failure does develop, a heart transplant may give the best chance of a return to normal health.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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