Aspirin-free strategy for percutaneous coronary intervention in acute coronary syndrome based on the subtypes of acute coronary syndrome and high bleeding risk: the STOPDAPT-3 trial

Abstract

Background and aims: High bleeding risk (HBR) and acute coronary syndrome (ACS) subtypes are critical in determining bleeding and cardiovascular event risk after percutaneous coronary intervention (PCI).

Methods and results: In 4476 ACS patients enrolled in the STOPDAPT-3, where the no-aspirin and dual antiplatelet therapy (DAPT) strategies after PCI were randomly compared, the pre-specified subgroup analyses were conducted based on HBR/non-HBR and ST-segment elevation myocardial infarction (STEMI)/non-ST-segment elevation ACS (NSTE-ACS). The co-primary bleeding endpoint was Bleeding Academic Research Consortium (BARC) type 3 or 5, and the co-primary cardiovascular endpoint was a composite of cardiovascular death, myocardial infarction, definite stent thrombosis, or ischaemic stroke at 1 month. Irrespective of the subgroups, the effect of no-aspirin compared with DAPT was not significant for the bleeding endpoint (HBR [N = 1803]: 7.27 and 7.91%, hazard ratio (HR) 0.91, 95% confidence interval (CI) 0.65-1.28; non-HBR [N = 2673]: 3.40 and 3.65%, HR 0.93, 95% CI 0.62-1.39; Pinteraction = 0.94; STEMI [N = 2553]: 6.58 and 6.56%, HR 1.00, 95% CI 0.74-1.35; NSTE-ACS [N = 1923]: 2.94 and 3.64%, HR 0.80, 95% CI 0.49-1.32; Pinteraction = 0.45), and for the cardiovascular endpoint (HBR: 7.87 and 5.75%, HR 1.39, 95% CI 0.97-1.99; non-HBR: 2.56 and 2.67%, HR 0.96, 95% CI 0.60-1.53; Pinteraction = 0.22; STEMI: 6.07 and 5.46%, HR 1.11, 95% CI 0.81-1.54; NSTE-ACS: 3.03 and 1.71%, HR 1.78, 95% CI 0.97-3.27; Pinteraction = 0.18).

Conclusion: In patients with ACS undergoing PCI, the no-aspirin strategy compared with the DAPT strategy failed to reduce major bleeding events irrespective of HBR and ACS subtypes. The numerical excess risk of the no-aspirin strategy relative to the DAPT strategy for cardiovascular events was observed in patients with HBR and in patients with NSTE-ACS.

Keywords: Acute coronary syndrome; Antiplatelet therapy; High bleeding risk; Non-ST-segment elevation acute coronary syndrome; ST-segment elevation myocardial infarction.