Antiplatelet Therapy Strategies in Patients with High Bleeding Risk Treated with Complex Percutaneous Coronary Intervention: A Descriptive Study

BACKGROUND: Following acute coronary syndrome (ACS) treated by percutaneous coronary intervention (PCI), guideline-directed dual antiplatelet therapy (DAPT) typically consists of 12 months of aspirin plus a P2Y12 inhibitor. Recent trials support antiplatelet de-escalation strategies in patients at high bleeding risk (HBR), whereas patients undergoing complex PCI are at increased thrombotic risk and may benefit from extended DAPT. The overlap between these groups with high bleeding risk and high thrombotic risk in contemporary practice is not well characterized. METHODS: Patients undergoing PCI for ACS were randomly sampled from those hospitalized at the Montreal Heart Institute between May 1, 2024 and April 30, 2025. Data were extracted from electronic health records. HBR was assessed using the Predicting Bleeding Complications in Patients Undergoing Stent Implantation and Subsequent Dual Antiplatelet Therapy-High Bleeding Risk (PRECISE-HBR) score, and complex PCI was assessed using guideline-based criteria. The primary objective was to estimate the proportion of patients meeting both criteria; secondary objectives described discharge antiplatelet strategies across risk groups. RESULTS: Of the 309 participants sampled, 35% were identified as being at HBR, 43% underwent complex PCI, and 17.5% (95% confidence interval, 13.3%-21.7%) met both HBR and complex PCI criteria. De-escalation strategies were infrequently prescribed across risk groups, even among patients at HBR without complex PCI. Among those not receiving long-term anticoagulation, only 4.2% received a de-escalation strategy. CONCLUSIONS: Nearly 1 in 6 patients undergoing PCI for ACS met both HBR and complex PCI criteria. In this setting, clinicians appeared to favour standard-duration clopidogrel-based DAPT rather than de-escalation approaches. These findings underscore the need for practical guidance to support individualized antiplatelet decision-making in patients with competing bleeding and ischemic risks.