An Aspirin-Free Strategy for Patients Undergoing Staged Percutaneous Coronary Intervention　- A Subgroup Analysis of the STOPDAPT-3 Trial.

BACKGROUND:

No previous studies have evaluated the effect of an aspirin-free strategy for patients undergoing staged percutaneous coronary intervention (PCI).

METHODS AND RESULTS:

We conducted a post hoc subgroup analysis in patients undergoing staged PCI within 1 month in STOPDAPT-3 (n=6,002), which randomly compared prasugrel monotherapy with dual antiplatelet therapy (DAPT) in patients with acute coronary syndrome or high bleeding risk. The co-primary endpoints were major bleeding (Bleeding Academic Research Consortium 3 or 5) and cardiovascular events (a composite of cardiovascular death, myocardial infarction, definite stent thrombosis, or stroke) at 1 month. There were 814 patients undergoing staged PCI within 1 month (no-aspirin group, n=401; DAPT group, n=413). The median interval from randomization to the first staged PCI was 8 (interquartile range 5-13) days. More than 90% of the patients received assigned antiplatelet agents at all staged PCI procedures. The effect of no-aspirin relative to DAPT was not different for the co-primary bleeding (3.74% vs. 1.94%; HR 1.94; 95% CI 0.82-4.57) and cardiovascular (3.49% vs. 2.42%; HR 1.44; 95% CI 0.64-3.25) endpoints. The no-aspirin group compared with the DAPT group had a numerically higher incidence of the co-primary cardiovascular endpoint, which occurred after the first staged PCI procedure (2.49% vs. 1.21%; HR 2.07; 95% CI 0.71-6.05).

CONCLUSIONS:

An aspirin-free prasugrel monotherapy relative to DAPT had numerically higher risks of cardiovascular and major bleeding events in patients undergoing staged PCI at 1 month.