heart and blood vessel disorders
Myocarditis
Causes of Myocarditis
Myocarditis may result from infectious or noninfectious causes. Many cases are unable to be identified (idiopathic). In the United States and most other developed nations, infectious myocarditis is most often caused by a viral infection. The most common viral causes in the United States are parvovirus B19 and human herpes virus 6. The COVID-19 sometimes causes myocarditis. In lower resource areas, infectious myocarditis is most often caused by ), certain drugs, and some autoimmune and inflammatory disorders. Myocarditis may also occur after mRNA-based COVID-19 Vaccine and is rare. It occurs mostly in adolescent and young adult males, usually within a week of vaccination. Myocarditis caused by drugs is termed hypersensitivity myocarditis. Giant cell myocarditis is a rare, severe form of myocarditis that has a rapid onset. The cause is unclear but may be autoimmune. A biopsy is done for diagnosis. In people with giant cell myocarditis, the heart is suddenly unable to pump enough blood to support the body's functions (called cardiogenic shock). People also frequently have abnormal heart rhythms that are hard to correct. Giant cell myocarditis has a poor prognosis but immunosuppressive therapy can help improve survival. 