Background: The effects of aspirin-free strategy on bleeding and cardiovascular events in patients undergoing percutaneous coronary intervention with oral anticoagulation (OAC) have not been fully elucidated.
Methods and results: We conducted the prespecified subgroup analysis based on the use of OAC, including vitamin K antagonist and direct oral anticoagulants, within 7 days before percutaneous coronary intervention in the STOPDAPT-3 (Short and Optimal Duration of Dual Antiplatelet Therapy-3) trial, which randomly compared prasugrel monotherapy (2984 patients) to dual antiplatelet therapy (DAPT) with prasugrel and aspirin (2982 patients) in patients with acute coronary syndrome or high bleeding risk. The coprimary end points were major bleeding events (Bleeding Academic Research Consortium types 3 or 5) and cardiovascular events (a composite of cardiovascular death, myocardial infarction, definite stent thrombosis, or ischemic stroke) at 1 month. Among 5966 study patients, there were 530 patients (8.9%) with OAC (no aspirin: N=248, and DAPT: N=282) and 5436 patients (91.1%) without OAC (no aspirin: N=2736, and DAPT: N=2700). Regardless of the use of OAC, the effects of no aspirin compared with DAPT were not significant for the bleeding end point (OAC: 4.45% and 4.27%, hazard ratio [HR], 1.04 [95% CI, 0.46-2.35]; no-OAC: 4.47% and 4.75%, HR, 0.94 [95% CI, 0.73-1.20]; P for interaction=0.82), and for the cardiovascular end point (OAC: 4.84% and 3.20%, HR, 1.53 [95% CI, 0.64-3.62]; no-OAC: 4.06% and 3.74%, HR, 1.09 [95% CI 0.83-1.42]; P for interaction =0.46).
Conclusions: The no-aspirin strategy compared with the DAPT strategy failed to reduce major bleeding events irrespective of the use of OAC. There was a numerical excess risk of the no-aspirin strategy relative to the DAPT strategy for cardiovascular events in patients with OAC.
Keywords: aspirin‐free strategy; oral anticoagulation; percutaneous coronary intervention.