Objective: Antiplatelet agents are used for prevention of thromboembolism in surgical patients and in patients with chronic atrial fibrillation. Up to date, however, results of randomized studies comparing antiplatelet agents and oral anticoagulation have not been reported. The aim of this study was to compare the efficacy and safety of triflusal (an antiplatelet agent) versus acenocoumarol for primary prevention of thromboembolism in the early postoperative period after implantation of a bioprosthesis.
Methods: In this prospective, multicentric, randomized, open pilot trial, patients were assigned to treatment with triflusal (600mg/d) or acenocoumarol (target INR 2.0-3.0). Study medication was started 24-48h after valve replacement with a bioprosthesis, and continued for 3 months. Four follow-up visits were scheduled: baseline, and at 1, 3 and 6 months thereafter. The primary end-point was a composite of the rate of thromboembolism, severe hemorrhage and valve-related mortality.
Results: A total of 193 patients were included (97 received triflusal and 96 acenocoumarol), with a mean age of 72.5 years. Half were men. Aortic valve replacement was performed in 181 patients (93.8%), mitral valve replacement in 10 patients (5.2%) and double valve replacement in 2 (1.0%). Hospital mortality was 11 (5.7%). Primary outcome was recorded in 9 patients with triflusal (9.4%) and in 10 patients with acenocoumarol (11%). There were nine episodes (4.7%) of thromboembolism, six in the triflusal group and three in the acenocoumarol group, and three episodes of permanent neurological deficits, one in the triflusal group and two in the acenocoumarol group. Severe hemorrhage: nine episodes, six in the acenocoumarol group and three in the triflusal group. None of the observed differences in efficacy were statistically significant. Regarding safety, three patients in triflusal group reported at least one hemorrhage, compared to 10 in acenocoumarol group (P=0.048).
Conclusions: There were no significant differences in efficacy between both groups, however, triflusal showed a significantly lower incidence of bleeding episodes.