Table of Contents
Definition of Myocarditis and Causes
Myocarditis is inflammation of the heart muscle, often as a consequence of viral infection that originates elsewhere in the body (such as a cold). Viruses known to cause myocarditis include measles, rubella, coxsackie, and cytomegalovirus (cmv).
Myocarditis also may be bacterial, or the consequence of cardiotoxic exposure (such as to radiation or carbon monoxide). The autoimmune processes of systemic inflammatory disorders such as systemic lupus erythematosus (sle), sarcoidosis, and rheumatoid arthritis also can involve the myocardium. A rare and severe form of myocarditis is giant cell myocarditis, an autoimmune disorder that specifically attacks the heart.
Symptoms, Diagnosis and Treatment
Myocarditis may have few symptoms until there is significant damage to the heart (commonly in the form of cardiomyopathy and arrhythmia), and often is life-threatening. Symptoms of early or chronic myocarditis may mimic those of influenza or of heart attack.
Diagnosis is by myocardial biopsy performed via cardiac catheterization, which reveals the infiltration of lymphatic cells and other characteristic changes in the myocardium that identify an inflammatory process. Chronic or advanced myocarditis may have fibrosis (scar tissue).