Giant Organized Thrombus in the Left Sinus of Valsalva Causing Intermittent Left Coronary Obstruction: An Unusual Case of Acute Myocardial Infarction

A 48-year-old Japanese man was admitted to hospital for acute myocardial infarction associated with a giant organized thrombus occupying the left sinus of Valsalva. Cardiac catheterization revealed no organic stenosis in either coronary artery, but left ventriculography and aortography showed a filling defect above the left coronary cusp. Transesophageal echocardiography was immediately performed and showed a round mass filling the left sinus of Valsalva. A solid, round mass approximately 2.5 cm in diameter was removed during emergency surgery and determined to be a thrombus on the basis of microscopic findings. This is the second report of a giant organized thrombus occupying the entire left sinus of Valsalva, obstructing the ostium of the left coronary artery intermittently, and leading to acute myocardial infarction. (Circ J 2004; 68: 795 - 798)