RIGHT VENTRICULAR ENDOMYOCARDIAL BIOPSY - CLINICOPATHOLOGIC CORRELATES IN 100 CONSECUTIVE PATIENTS

Abstract

The first 100 consecutive patients to undergo right ventricular endomyocardial biopsy at the Mayo Clinic [Rochester, Minnesota, USA] were divided retrospectively into 5 groups, depending on the prebiopsy clinical diagnosis. The biopsies were reviewed histologically in a single-blind format. Group 1 consisted of 34 patients with a diagnosis of unexplained congestive heart failure and a dilated heart; of these, 4 (12%) had active myocarditis by biopsy. Of the 6 patients in group 2 with a clinical diagnosis of myocarditis, only 1 (17%) had biopsy evidence of inflammation, but 2 (33%) had changes that, in the clinical setting, were suggestive of cardiomyopathy. Group 3 consisted of 27 patients with dysrhythmia, syncope or cardiac arrest but without congestive heart failure; of these, 4 (15%) had active myocarditis by biopsy and 8 (30%) had changes that, with the clinical history, were consistent with cardiomyopathy. Group 4 included 19 patients with unexplained congestive heart failure and a nondilated heart; 4 (21%) had cardiac amyloid on biospy. Group 5 was a diverse group of 14 patients with possible cardiac involvement by a known systemic disease; myocardial disease was documented by biopsy in 7 (50%). Endomyocardial biopsy is suggested in the following groups: in patients with dilated cardiomyopathy in whom myocarditis is suspected, in patients with the clinical diagnosis of active myocarditis in whom tissue documentation is indicated before treatment with antiinflammatory or immunosuppressive drugs, in patients with clinically unexplained life-threatening dysrhythmias in whom myocarditis or cardiomyopathy may be present, and in patients with apparent hypertrophic or restrictive cardiomyopathy in whom cardiac amyloid may be present.