[Surgical removal of native aortic valve thrombosis associated with acute myocardial infarction and protein C deficiency; report of a case].

Native aortic valve thrombosis is an uncommon event. We describe the case of a 76-year-old man who suffered acute myocardial infarction associated with native aortic valve thrombosis diagnosed by cardiac catheterization. Since the thrombus was localized on the right coronary cusp and occluded right coronary artery, rescue revascularization was performed using perfusion catheter, which was continuously engaged to the right coronary artery. Operation was immediately performed under cardiopulmonary bypass. After incision of ascending aorta, thrombus was removed easily and aortic valve was preserved without degenerative change. Histological study showed a typical thrombus without any specific findings. He had a good clinical course and discharged 9 days after the operation. He had no history of heart valve disease, left heart catheterization or bacterial endocarditis. Since laboratory data showed 41% in protein C antigen and 32% of protein C activity, he was diagnosed of protein C deficiency. Our report emphasize that this thrombus formation may be caused by protein C deficiency.