Comparing warfarin to aspirin after aortic valve replacement with epic prosthesis: early results of prospective randomized trial

Objectives: Patients with prosthetic heart valves have a higher risk of developing valve thrombosis and arterial thromboembolism. Antithrombotic therapy in the early postoperative period after biological aortic valve replacement (BAVR) is controversial. This prospective randomized single institution study investigated the efficacy of postoperative warfarin compared to aspirin in patients after aortic valve replacement with St.Jude Epic prosthesis (SJEP). Methods: A total of 73 patients underwent BAVR with SJEP in 2003. They received two different antithrombotic therapies: 35 patients received warfarin (INR; range 2 to 3) for the first three months. Thirty four patients received only aspirin (100mg/day). Four patients were escluded during follow up for comparison of atrial fibrillation. The major endpoints evaluated were the rate of cerebral ischemic events, bleeding and survival. Results: There was 1 postoperative cerebral ischemic event for each group of treatment between 24 hours and 3 months (2.8%vs 2.9%, ns). After 3 months, the incidence of cerebral ischemic events did not differ between the two groups. The rate of major bleeding events, the stroke-free survival and the overall survival rates were not statistically significant between the warfarin and ASA groups. Conclusions: There seem to be no advantages in carrying out early anticoagulation therapy compared to low antiplatelet regimen with regards to early cerebral ischemic events, bleeding and survival for SJEP. At the moment, regarding to the early results presented, there is no evidence to support the fact that SJEP should receive warfarin for prevention of valve thrombosis and arterial thromboembolism.