[Secondary immunopathogenesis of cardiac diseases]

Antimyolemmal antibodies can be demonstrated in sera of patients with coxsackie B, influenza, mumps and Q-fever perimyocarditis, in sera of patients with postpericardiotomy and postinfarction syndromes, in part of the sera of patients with endocarditis and in some patients with dilated heart disease most likely due to secondary immunopathogenesis after perimyocarditis. Antimyolemmal antibodies in titres greater than 1: 40 are complement fixing and cytolytic when added to cultures of vital myocytes. In vitro cardiocytolysis indicates that humoral effector mechanisms could also play a pathogenetic role in vivo. In vitro antibody dependent and independent cellular cytotoxicity of patients lymphocytes against isolated cardiocytes could not be observed in perimyocarditis and postmyocarditic cardiomyopathy. It could be demonstrated, however, in patients with postpericardiotomy syndrome and in some patients with dilated cardiomyopathies. Immunological investigations are therefore not only of diagnostic significance but have widened our knowledge of the etiology and pathogenesis of perimyocardial diseases. Furthermore they are helpful in the follow-up and prognosis of patients with protracted perimyocardial affections.