Clinical Impact of Dual Antiplatelet Therapy Use in Patients Following Everolimus-eluting Stent Implantation： Insights from the SEEDS Study

Background： Studies have suggested that use of prolonged dual antiplatelet therapy （DAPT） following new generation drug-eluting stent implantation may increase costs and potential bleeding events. This study aimed to investigate the association of DAPT status with clinical safety in patients undergoing everolimus-eluting stent （EES） implantation in the SEEDS study （A Registry to Evaluate Safety and Effectiveness of Everolimus Drug-eluting Stent for Coronary Revascularization） at 2-year follow-up. Methods： The SEEDS study is a prospective, multicenter study, where patients （n = 1900） with small vessel, long lesion, or multi-vessel diseases underwent EES implantation. Detailed DAPT status was collected at baseline, 6-month, 1- and 2-year. DAPT interruption was defined as any interruption of aspirin and/or clopidogrel more than 14 days. The net adverse clinical events （NACE, a composite endpoint of all-cause death, all myocardial infarction （MI）, stroke, definite/probable stent thrombosis （ST）, and major bleeding （Bleeding Academic Research Consortium II-V）） were investigated according to the DAPT status at 2-year follow-up. Results： DAPT was used in 97.8% of patients at 6 months, 69.5% at 12 months and 35.4% at 2 years. It was observed that the incidence of NACE was low （8.1%） at 2 years follow-up, especially its components of all-cause death （0.9%）, stroke （1.1%）, and definite/probable ST （0.7%）. DAPT was not an independent predictor of composite endpoint of all-cause death/Ml/stroke （hazard ratio [HR]： 0.693, 95% confidence interval [C/I： 0.096-4.980, P = 0.715） and NACE （HR： 1.041, 95% CI： 0.145-7.454, P = 0.968）. Of 73 patients who had DAPT interruption, no patient had ST at 12-month, and only 1 patient experienced ST between 1- and 2-year （I.4%）. There was a high frequency of major bleeding events （53/65, 82.5%） occurred in patients receiving DAPT treatment. Conclusions： Prolonged DAPT use was not associated with improved clinical safety. The study emphasized that duration of DAPT needs to be shortened in Chinese patients following EES implantation （ClinicalTrials.gov identifier： NCT 01157455）.