Usefulness of endomyocardial biopsy in tertiary care.

Over a 51-month period, 143 patients underwent right ventricular endomyocardial biopsy as part of their evaluation for cardiac disease. Of these, 82 patients presented with a clinical dilated cardiomyopathy, 28 patients with unexplained arrhythmia, 22 with other cardiomyopathies, 7 with anthracycline exposure, and 4 with miscellaneous indications. Overall, 47 of the 143 patients (33%) had findings on endomyocardial biopsy that changed the clinical diagnosis. Of these, 18 (38%) had a change in diagnosis based on nonspecific criteria. Although 32 of the 143 patients (22%) had specific therapeutic alterations based on the endomyocardial biopsy findings, the vast majority of these received immunosuppression for myocarditis, a therapy that is currently of unproven benefit. Therefore, endomyocardial biopsy is of limited therapeutic use for most patients with primary myocardial disease. Its current primary indications are for clinical diagnosis and investigation.