The use of endomyocardial biopsy in heart failure.

Endomyocardial biopsy in this study of 1250 biopsied patients (mean of five samples/patient) proved to be a remarkably safe technique with no lethal complications. It may help to detect the underlying cause of heart failure but is handicapped by sampling error in focal disease processes (such as myocarditis and sarcoid heart disease) when conventional light and electron microscopy are used. In this biopsy series 123 patients (9.8%) suffered from severe heart failure; lymphocytic infiltrates were found in only 10 (8%). Immunohistological data suggested a secondary humoral immunopathogenesis in all patients with myocarditis and perimyocarditis, in 75% of patients with postmyocarditic heart muscle disease and in 48% of patients with primary dilated cardiomyopathy. There may thus be a need for a new classification of heart muscle diseases that includes immunological parameters of humoral and cellular autoreactivity.