Abbreviated versus standard dual antiplatelet therapy time after PCI in high bleeding risk patients with acute coronary syndrome - a report from the SWEDEHEART registry

Background The use of a short duration of dual antiplatelet therapy (DAPT) has become increasingly common in patients with high bleeding risk (HBR). This study aimed to evaluate outcomes for an abbreviated DAPT strategy compared to standard DAPT time strategy for high bleeding risk-patients with acute coronary syndrome (ACS) treated with percutaneous coronary intervention (PCI). Methods A total of 22310 patients from the SWEDEHEART-registry with at least one high bleeding risk criteria who underwent PCI for ACS in Sweden between January 1, 2013, until January 15, 2021, were enrolled. Patients were grouped according to their planned DAPT time at discharge: standard DAPT with 12 months of any P2Y12 inhibitor and aspirin or an abbreviated DAPT duration (<6 months DAPT or 12-month single APT) and matched for intended P2Y12 inhibitor type (clopidogrel or prasugrel/ticagrelor). The primary outcome was net adverse clinical events (NACE) at one year defined as the first occurrence of cardiac mortality or hospitalization due to myocardial infarction, ischemic stroke or clinically significant bleeding. Major adverse cardiovascular events and the individual components of NACE were defined as secondary endpoints. Results No significant difference in NACE was observed between the abbreviated compared to standard DAPT time groups, Kaplan-Meier event rate: 12.9% (n = 584) vs 13.1% (n = 594) hazard ratio (HR) 0.99; 95% confidence interval (CI) 0.88-1.11, p=0.83. No differences were observed for MACE (HR 1.08; 95% CI 0.94-1.25) or any of the elements of the primary composite outcome. The results were consistent in all HBR-subgroups. Conclusion For patients with a high bleeding risk undergoing PCI due to an ACS, an abbreviated DAPT strategy was associated with comparable rates of NACE and MACE as compared to a standard DAPT time strategy. The results add real-world evidence that abbreviated DAPT-regimes can be a viable treatment option for patients with ACS with a high bleeding risk.