Left atrial leiomyosarcoma: manifestation as unexplained pulmonary vascular disease.

Primary, left-sided cardiac tumors are a rare cause of unexplained pulmonary hypertension. We describe herein two patients with leiomyosarcoma of the left atrium, who were initially seen with symptoms suggestive of primary pulmonary hypertension, venoocclusive disease, or multiple, small thromboemboli. Postmortem examination showed extension of the leiomyosarcoma into the pulmonary veins, which resulted in pulmonary venous hypertension. Although unusual, the occurrence of left-sided cardiac neoplasms should be included in the differential diagnosis of patients who are initially seen with unexplained pulmonary hypertension. An open lung biopsy should be considered and may indicate a venous origin for the hypertension.