Failure of Guideline-based Anticoagulation in a Patient with Mitral Prosthetic Valve and Recurrent Thromboembolism

Prosthetic valve (PV)-related thromboembolism is a rare but serious complication of implanted mechanical valves. There is not a design that has yet achieved mechanical perfection; therefore, using these mechanical valves is not free of mortality and morbidity. Some of the complications of using such valves include PV thrombosis, systemic embolization, bleeding, endocarditis, perivalvular leak, and structural valve failure. These valves are thrombogenic, and their use requires anticoagulation postoperatively to prevent systemic embolization and PV thrombosis. This intervention also carries the risk of bleeding, which can be detrimental for a subset of patients, especially elderly, pregnant, and those with other systemic comorbidities. In this case we present a patient with recurrent thromboembolic events and a nonobstructing St. Jude mitral PV thrombosis despite vigorous anticoagulation with Coumadin (Bristol-Myers Squibb Co., Princeton, NJ) and aspirin.