Prolonged dual antiplatelet therapy after drug-eluting stent implantation improves long-term prognosis for acute coronary syndrome: five-year results from a large cohort study.

Abstract

To investigate the most appropriate dual antiplatelet therapy (DAPT) duration for patients with acute coronary syndrome (ACS) after drug-eluting stent (DES) implantation in the largest cardiovascular center of China. We enrolled 5,187 consecutive patients with ACS who received DES from January to December 2013. Patients were divided into four groups based on DAPT duration: standard DAPT group (11-13 months, n=1,568) and prolonged DAPT groups (13-18 months [n=308], 18-24 months [n=2,125], and >24 months [n=1,186]). Baseline characteristics and 5-year clinical outcomes were recorded. Baseline characteristics were similar across the four groups. Among the four groups, those with prolonged DAPT (18-24 months) had the lowest incidence of major adverse cardiovascular and cerebrovascular events (MACCEs) (14.1% vs. 11.7% vs. 9.6% vs. 24.2%, P<0.001), all-cause death (4.8% vs. 3.9% vs. 2.1% vs. 2.6%, P<0.001), cardiac death (3.1% vs. 2.6% vs. 1.4% vs. 1.9%, P=0.004), and myocardial infarction (MI) (3.8% vs. 4.2% vs. 2.5% vs. 5.8%, P<0.001). The incidence of bleeding was not different among the four groups (9.9% vs. 9.4% vs. 11.0% vs. 9.4%, P=0.449). Cox multivariable analysis showed that prolonged DAPT (18-24 months) was an independent protective factor for MACCEs (hazard ratio [HR] 0.802, 95% confidence interval [CI] 0.729-0.882, P<0.001), all-cause death (HR 0.660, 95% CI 0.547-0.795, P<0.001), cardiac death (HR 0.663, 95% CI 0.526-0.835, P<0.001), MI (HR 0.796, 95% CI 0.662-0.957, P=0.015), and target vessel revascularization (HR 0.867, 95% CI 0.755-0.996, P=0.044). Subgroup analysis for high bleeding risk showed that prolonged DAPT remained an independent protective factor for all-cause death and MACCEs. For patients with ACS after DES, appropriately prolonging the DAPT duration may be associated with a reduced risk of adverse ischemic events without increasing the bleeding risk.