Myocarditis is an inflammation of the heart muscle.
Myocarditis is collection of diseases of infectious, toxic, and autoimmune. Myocarditis may develop as a complication of an infectious disease, usually caused by a virus. It can occur in people of all ages and is diagnosed more often in men than in women. Myocarditis is likely caused by a wide variety of infectious organisms, autoimmune disorders, and exogenous agents, with genetic and environmental predisposition. Myocarditis is defined as inflammatory changes in the heart muscle and is characterized by myocyte necrosis. Many organisms can infect and injure the heart. Type B, a virus among those that usually infect the gastrointestinal tract, is believed to be the most common offending agent. Many other viruses, such as those of polio, rubella and influenza, have been associated with myocarditis. Myocarditis can occur as a rare complication of bacterial infections, including diphtheria, tuberculosis, typhoid fever, and tetanus. Other infectious organisms, such as rickettsia and parasites, may also cause inflammation in the heart muscle.
Myocarditis is often associated with pericarditis, and many patients present with signs and symptoms that suggest concurrent myocarditis and pericarditis. Myocarditis can be caused by a variety of pathogens including bacteria, viruses, and parasites. Some people have an irregular heartbeat (arrhythmia) or trouble breathing. Usually, a mild case of myocarditis will go away without any lasting damage. Myocarditis can then cause heart failure (with symptoms of shortness of breath, fatigue, fluid accumulation in the lungs, etc.) as well as heart rhythm irregularities from inflammation and/or scarring of the electrical system of the heart. Most cases of myocarditis are subclinical; therefore, the patient rarely seeks medical attention during acute illness. These subclinical cases may have transient ECG abnormalities. Certain chemicals. These may include substances such as arsenic and hydrocarbons. Medications that may cause an allergic or toxic reaction. These include antibiotics such as penicillin and sulfonamide drugs, as well as some illegal substances, such as cocaine.
Myocarditis may start as a flu-like illness that lingers longer than the usual several days. In series of routine autopsies, 1-9% of all patients had evidence of myocardial inflammation. In young adults, up to 20% of all cases of sudden death are due to myocarditis. In South America, Chagas' disease (caused by Trypanosoma cruzi) is the main cause of myocarditis.
As most viral infections cannot be treated with directed therapy, symptomatic treatment is the only form of therapy for those forms of myocarditis, e.g. NSAIDs for the inflammatory component and diuretics and/or inotropes for ventricular failure.
Treatment for Myocarditis