Myocarditis is an inflammation of the heart’s muscular wall, the myocardium. Although rare, it can be devastating. Myocarditis can occur with no symptoms and remain undiagnosed.

Healthy Myocardium
normal heart section
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Many cases of myocarditis have no identifiable cause. This is called idiopathic myocarditis. When a cause is identified, it falls into one of three categories: infectious, toxic, or immune-mediated.

Infectious
Toxic
  • Drugs, including chemotherapeutic drugs, lithium , or cocaine
  • Heavy metals, including copper, iron, or lead
  • Toxic substances, including arsenic, carbon monoxide, or other inhalants
  • Physical agents, including electric shock or radiation
Immune-mediated
  • Allergic reactions to penicillin or streptomycin
  • Alloantigens, including heart transplant rejection
  • Autoantigens, including Chagas’ disease, scleroderma, or lupus