Myocarditis is the inflammation of the heart muscle (myocardium) and is caused most of the time by a viral infection.
In rare cases, myocarditis is the result of a toxic reaction to a medication or the injection of an illegal drug, such as cocaine.
As the patient's condition deteriorates, the heart's capacity to pump blood diminishes, which results in reduced blood supply to all of the organs. Heart inflammation caused by the virus decreases the strength of its contractions and its ability to supply the body with blood.
In less severe cases of myocarditis, people may not experience any symptoms. However, they may feel symptoms similar to those of the flu: headache, fever, sore throat, joint pain and diarrhea.
In more severe cases of the illness, other symptoms may also be present:
- Chest pain
- Arrhythmia (fast or irregular heart beat)
- Shortness of breath upon exertion or even at rest
- Retention of fluids and swelling in the legs
- Fatigue
After filling out a comprehensive questionnaire and performing a physical exam, the doctor will prescribe one of the following tests if he or she suspects myocarditis:
- Electrocardiogram (ECG)
- Blood tests
- Echocardiogram
- Cardiac MRI
- Biopsy
In the majority of cases, patients improve on their own or with the help of treatment to support their heart function until they fully recover. Antiviral treatments do exist, but their efficacy has not yet been proven.
Since the heart never fully recovers after the acute phase of a viral infection, drug treatment must be continued to treat the heart failure.