Floating thrombus in the ascending aorta: a rare cause of peripheral emboli.

The ascending aorta may be the site of origin of systemic embolization in some cases that do not have an identifiable source. We report a case in which a free-floating thrombus in the noncoronary sinus of Valsalva was detected by transesophageal echocardiography as a source of left axillary artery embolism. After removal of this pedunculated thrombus of unknown cause, which was attached on a macroscopically and histologically normal aortic wall, the patient made an uneventful recovery.