Safety of drug eluting stents in patients on chronic anticoagulation using long-term single antiplatelet treatment with clopidogrel.

BACKGROUND: Use of triple therapy with aspirin, clopidogrel, and anticoagulants significantly increases bleeding, thus drug eluting stents (DES) are usually avoided in patients requiring anticoagulation. We tested use of DES vs. BMS using a long-term therapy with clopidogrel only and anticoagulants in this group of patients.

METHODS: We enrolled 165 consecutive patients, 79 receiving DES (age 67 +/- 9 years, 84% with atrial fibrillation) and 86 receiving bare metal stents (BMS) (age 70 +/- 11 years, 71% with atrial fibrillation). All patients received aspirin + clopidogrel + oral anticoagulants for 4 weeks, then aspirin was stopped and clopidogrel was continued during the 12-month follow-up. Primary end point was the combined incidence of major adverse coronary events and major bleedings.

RESULTS: Incidence of the primary endpoint was 10.1% in patients with DES and 26.7% in patients with BMS (P = 0.01). There was a large difference in incidence of target vessel revascularization (8.1% for DES, 23.3% for BMS, P = 0.01), whereas incidence of myocardial infarction (3.8% in DES vs. 8.1% in BMS) and major bleeding (1.3% vs. 2.3%, respectively) were not significantly different. There were no cases of stent thrombosis. On multivariate Cox regression analysis, the only factor associated with a reduced risk of the primary endpoint was use of DES (hazard ratio 0.35 with 95% confidence interval 0.14-0.85, P = 0.02).

CONCLUSIONS: Results of our cohort study suggest that use of DES associated with a treatment with clopidogrel only may be safe and significantly reduce the need for new revascularization in patients requiring chronic anticoagulation.