Abstract MP19: New Insight Into The Optimal Duration Of DAPT Following PCI In High-risk Twilight-like Patients With Acute Coronary Syndrome

Abstract

Introduction: Recent emphasis on shorter DAPT regimen after PCI irrespective of indication for PCI may fail to account for the substantial residual risk of recurrent atherothrombotic events in ACS patients. We aim to determine the association of extended-term (>12-month) vs. short-term dual antiplatelet therapy (DAPT) with ischemic and hemorrhagic events in high-risk "TWILIGHT-like" patients undergoing PCI for ACS in clinical practice. Methods: All consecutive patients fulfilling the "TWILIGHT-like" criteria undergoing PCI were identified from the prospective Fuwai PCI Registry. High-risk patients (n=5,404) were defined by at least 1 clinical and 1 angiographic feature based on TWILIGHT trial selection criteria. The primary ischemic endpoint was major adverse cardiac and cerebrovascular events at 30 months, composed of all-cause mortality, myocardial infarction, or stroke while BARC type 2, 3, or 5 bleeding was key secondary outcome. Results: The proportion of patients with 1-3, 4-5, or 6-9 risk factors was 19.7%, 58.6%, and 21.6%, respectively. Cessation of DAPT was less frequent in patients with ACS at 12 months (31.6% versus 68.4%), with 22.7% of ACS patients still on DAPT beyond 24 months. Of 4,875 high-risk ACS patients who remained event-free at 12 months after PCI, DAPT>12-month compared with shorter DAPT reduced the primary ischemic endpoint by 63% (1.5% vs. 3.8%; HRadj: 0.374, 95% CI: 0.256 to 0.548; HRmatched: 0.361, 95% CI: 0.221-0.590). The HR for cardiovascular death was 0.049 (0.007 to 0.362) and that for MI 0.45 (0.153 to 1.320) and definite/probable stent thrombosis 0.296 (0.080-1.095) in propensity-matched analyses. Rates of BARC type 2, 3, or 5 bleeding (0.9% vs. 1.3%; HRadj: 0.668 [0.379 to 1.178]; HRmatched: 0.721 [0.369-1.410]) did not differ significantly between two groups. Conclusions: Among high-risk ACS patients undergoing PCI, long-term DAPT, compared with shorter DAPT, reduced ischemic events without a concomitant increase in clinically meaning bleeding events, suggesting that long-term DAPT can be considered in patients with ACS following PCI who are carefully assessed to be at low bleeding risk and heightened ischemic risk, and have tolerated antiplatelet therapy without a major bleeding during 1 year of DAPT.