Prognostic significant of indium-111 antimyosin antibody uptake in patients with dilated and hypertrophic cardiomyopathy.

The prognostic significance of myocardial uptake of indium-111 antimyosin was evaluated in 15 patients with idiopathic cardiomyopathy: 10 patients with dilated cardiomyopathy and 5 patients with hypertrophic cardiomyopathy. Seven of the 10 patients with dilated cardiomyopathy showed positive images; three of these 7 patients with strongly positive scans died within 3 months after scintigraphic examination. Four of the 5 patients with hypertrophic cardiomyopathy showed positive images; two of these patients with dilated left ventricle had prominent positive scans and higher heart to lung ratio. One of these two patients died 12 months after antimyosin scan. The heart to lung ratio of antimyosin uptake in total patients was correlated with left ventricular end-diastolic dimension (r = 0.51, P less than 0.05), end-systolic dimension (r = 0.57, P less than 0.05) and ejection fraction (r = -0.60, P less than 0.05) measured by echocardiography. Although the number of patients is small and the study is preliminary, indium-111 antimyosin antibody imaging could be of value in establishing prognosis of patients with dilated and hypertrophic cardiomyopathy, in selecting patients for cardiac transplantation, and in evaluating the effects of therapeutic interventions.