Myocarditis is an inflammation of the myocardium, which is the heart’s muscular wall. Although rare, it can be devastating. Myocarditis can occur with no symptoms and remain undiagnosed. It can also occur with great intensity and lead to congestive heart failure.
A large percentage of myocarditis cases have no identifiable cause. This is called idiopathic myocarditis. When a cause is identified, it falls into one of the following categories: infectious, toxic, or immune-mediated.
- Viral infection, including:
- Measles virus
- Rabies virus
- Bacterial infection, including:
- Fungal infection, including:
- Drugs, including:
- Chemotherapeutic drugs
- Heavy metals, including:
- Toxic substances, including:
- Carbon monoxide
- Physical agents, including:
- Alloantigens, including:
- Heart transplant rejection
- Autoantigens, including:
- Chagas’ disease
There are no known risk factors for developing myocarditis.
The symptoms of myocarditis vary from person-to-person depending on the cause and the severity. Symptoms may appear slowly or come on suddenly. Some people have no symptoms (asymptomatic).
- Flu-like complaints, including fever, fatigue, muscle pain, vomiting, diarrhea, and weakness
- Rapid heart rate
- Chest pain
- Shortness of breath and respiratory distress
- Loss of consciousness
- Sudden, unexpected death
If you have any of these symptoms you should contact your doctor right away.
The diagnosis of myocarditis is often difficult; there is no specific test to diagnose it. Many other causes of heart problems must be ruled out. To do this, your doctor will ask about your symptoms and medical history, and perform a physical exam.
Tests may include the following:
- Electrocardiogram (ECG)–a test that records the heart’s activity by measuring electrical currents through the heart muscle
- Chest X-ray–a test that uses radiation to take pictures of structures inside the body
- Cardiac Enzyme –measured through blood tests; in some cases certain enzymes are elevated
- Echocardiogram–a test that uses high-frequency sound waves (ultrasound) to examine the size, shape, and motion of the heart
- Biopsy–removal of a sample of heart tissue to test for infection
- Cardiovascular magnetic resonance–the use of magnetic waves to take pictures of structures inside the body
The universally recommended therapy for myocarditis is bed rest, 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 the cause is a bacterial infection, antibiotics are prescribed. If it is viral, antiviral agents will be prescribed. Immunosuppressive therapy may be recommended in people if myocarditis is due to an autoimmune disorder such as lupus or scleroderma.
If heart failure symptoms are present, medications are given to support the function of the heart. These include diuretics, ACE-inhibitors, beta-blockers, and antiarrhythmic 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.
Myocarditis is hard to prevent. To help reduce your chances of getting myocarditis, reduce your exposure to identified causes. Some examples include:
- Practice good hygiene to avoid the spread of infection–for example, wash your hands regularly
- Always use latex condoms during sexual activity
- Have sex with only one partner (who has sex only with you)
- Do not use illegal drugs