Humoral and cellular immune reactions to the myocardium in myocarditis.

Myocarditis is characterized by an infiltration of poly- and mononuclear leucocytes next to necrosis of myofibers in the heart. Various viruses induce this cardiac disorder in most cases, either by their direct cytotoxic action on the cardiocytes or by humoral and cellular immune reactions to the myocardium arising after the infection. Epidemiological and experimental and serological studies suggest, that viral myocarditis may lead to dilated heart muscle disease. Therapy consists of reducing cardiac stress by physical inactivity and drugs decreasing cardiac pre- and afterload. Immunosuppression is beneficial in some but not all patients with myocarditis.