Background: Although combination therapy for various cardiac conditions with dual antiplatelet therapy (aspirin and thienopyridine derivatives) and warfarin sodium has become increasingly popular, the safety and effectiveness of this aggressive treatment regimen remain unknown.
Methods and results: We retrospectively enrolled and analyzed 575 consecutive patients who had been implanted with drug-eluting coronary stents. The primary and secondary endpoints were major bleeding complications and major adverse cardiovascular events (MACE), respectively. At the time of discharge, 525 patients (91.3%) were prescribed with dual antiplatelet therapy, and 50 (8.7%) of them received dual antiplatelet plus anticoagulant therapy (triple therapy). The patients treated with triple therapy had a greater prevalence of comorbid conditions, including left ventricular systolic dysfunction and multi-vessel coronary disease compared to those on the dual antiplatelet regimen. During a median follow-up of 459 days, 14 (2.7%) patients receiving dual, and 9 (18.0%) receiving triple therapy reached the primary endpoint (p<0.001). These results show that warfarin use was associated with an increased risk of subsequent major bleeding. On the other hand, the incidence of MACE did not differ between the two groups (p=0.108 by the log-rank test). Multivariate analysis showed that renal impairment was an independent predictor of the risk of subsequent major bleeding in the triple therapy group.
Conclusions: Triple therapy increased the hemorrhagic complications in patients after percutaneous coronary intervention with drug-eluting stents, especially in patients with impaired renal function. Great caution should be taken with patients who necessitate the addition of anticoagulation therapy with warfarin to dual antiplatelet therapy.
Copyright 2010 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.