Tumor invasion of the pulmonary veins: a unique source of systemic embolism detected by transesophageal echocardiography.

Two patients with a malignancy involving the lungs and spontaneous systemic embolization in whom transesophageal echocardiography detected masses consistent with tumor invading the pulmonary veins are reported. In the first patient, tumor embolization resulted in acute aortic obstruction. Transesophageal echocardiography revealed tumor present in the pulmonary veins that extended into the left atrium. This was confirmed by magnetic resonance imaging. The second patient had a stroke. Transesophageal echocardiography demonstrated a mass in the right pulmonary vein in this patient as well. In patients with pulmonary malignancy who have a systemic embolic event, tumor emboli from the pulmonary vein should be included in the differential diagnosis of possible causes of the event. Transesophageal echocardiography is a valuable tool for diagnosis of tumor involvement of the pulmonary veins in such patients.