Spontaneous native aortic valve thrombosis.

Spontaneous thrombosis of a native aortic valve is an uncommon event that usually follows local trauma, such as cardiac surgery or left heart catheterization, or occurs as a complication of bacterial endocarditis. We report the case of a 65-year-old woman with a history of retinal artery occlusion and severe aortic valve stenosis, in whom transesophageal echocardiography revealed a mobile mass attached to the ventricular surface of the aortic valve. There was no evidence of any hypercoagulable state or infection process. Surgery was performed and a severely stenotic valve resected; a partially organized and firmly adherent free-floating thrombotic mass was observed on the ventricular surface of the aortic valve. Histologic examination demonstrated an organized thrombus. Eleven months after surgery the patient is doing well.