DIAGNOSIS OF PRIMARY CARDIAC LEIOMYOSARCOMA BY ENDOMYOCARDIAL BIOPSY

We report a case of a primary right ventricular leiomyosarcoma in a 58 -year-old woman diagnosed by endomyocardial biopsy. Clinical findings included a 5-year history of atypical chest pain and atrial fibrillati on as well as a 30-lb weight loss. A ventricular mass was identified b y echocardiography and magnetic resonance imaging, and an endomyocardi al biopsy was performed. Biopsy was guided by right ventriculography, which revealed a mobile mass in the cavity of the right ventricle. Lig ht microscopy revealed a fasciculated, spindle cell sarcoma, most cons istent with leiomyosarcoma, and immunohistochemical staining for muscl e-specific actin was strongly positive in nearly all tumor cells, conf irming its myogenous differentiation. Endomyocardial biopsy provided a definitive tissue diagnosis of this rare primary malignant cardiac ne oplasm without the need for a surgical procedure.