Abstract 18475: Is There Any End in Sight to This Debate on the Optimal Duration of Dual Antiplatelet Therapy After Drug-eluting Coronary Stent Implantation?

Abstract

Introduction: There is no end in sight to the ongoing debate on the optimal duration of dual antiplatelet therapy (DAPT) following drug-eluting coronary stent (DES) implantation. Hypothesis: Short-term DAPT is less effective than long-term DAPT in preventing adverse cardiovascular and cerebrovascular outcomes following DES. Methods: MEDLINE, EMBASE, Scopus and CENTRAL were searched for eligible randomized controlled trials (RCTs) that compared short-term (≤ 6 months) DAPT with long-term (≥ 12 months) DAPT following DES implantation. The primary end point was a composite of all cause death, myocardial infarction, target vessel revascularization, stroke or major bleeding. The secondary outcome were the individual components of the primary outcome, cardiovascular death, stent thrombosis and any bleeding episode. Results: A total of 15,378 patients from 7 RCTs were studied. There was no statistically significant difference between the short-term and long-term DAPT groups with respect to the occurrence of the primary outcome {Risk ratio (RR) 1.017 (0.872-1.186), I2 = 0%}, all cause death {RR 0.896 (0.708-1.134)}, cardiovascular death {RR 0.924 (0.668-1.279)}, myocardial infarction {RR 1.139 (0.887-1.461)}, target vessel revascularization {RR 1.174 (0.916-1.505)}, stent thrombosis {RR 1.264 (0.786-2.032)} and stroke {RR 0.876 (0.685-1.611)}. However there was a statistically significant lower risk of major bleeding in the short-term DAPT group {RR 0.57 (0.36-0.90), p 0.02}. There was no statistically significant difference in the sub-group analysis of patients with diabetes and patients presenting with acute coronary syndrome, {RR 1.029 (0.745-1.421)} and {RR 1.062 (0.785-1.438)}, respectively. Conclusion: There was no difference in efficacy outcomes between short-term and long-term DAPT following DES, even among high-risk patients. Longer duration of DAPT was found to be associated with increased risk of major bleeding. These results are contrary to findings from the recently published DAPT trial. However, even though the DAPT trial reported a significant decrease in the incidence of stent thrombosis and major adverse cardiac and cerebrovascular events in the long-term DAPT group, there was a paradoxical increase in mortality.