- 6 months of DAPT in patients with HBR and ACS after PCI.
- 12 months of DAPT in patients without HBR and with ACS after PCI.
- In patients without ACS, 1 to 3 months of DAPT in patients with HBR after PCI.
ESC 2023: New data showed an aspirin-free strategy after PCI did not reduce major bleeding event risk vs DAPT, while omission of aspirin proved noninferior for CV events in high-risk patients.
An aspirin-free strategy following percutaneous coronary intervention (PCI) did not reduce major bleeding event risk compared with dual antiplatelet therapy (DAPT), according to data from the STOPDAPT-3 clinical trial. Omission of aspirin, however, proved noninferior for cardiovascular (CV) events in high-risk patients.
Findings were presented in a Hot Line session at the European Society of Cardiology (ESC) 2023 Congress in Amsterdam.
“The aspirin-free strategy compared with the DAPT strategy failed to reduce major bleeding within 1 month after PCI, but it was non-inferior for the co-primary cardiovascular endpoint with a relative 50% margin,” said presenting author Masahiro Natsuaki, MD, of Saga University in Japan, in an ESC press release.
According to the ESC release, short durations (ie, 1-3 months) of DAPT followed by P2Y12 inhibitor monotherapy has been found to decrease bleeding events without increasing cardiovascular (CV) events compared with standard durations of DAPT post-PCI using drug-eluting stents. “However,” wrote the ESC, “the incidence of major bleeding events within the 1-month mandatory DAPT period after PCI remains high in real clinical practice, particularly in patients with [acute coronary syndrome] or [high bleeding risk].”
It is possible that bleeding events during early weeks after PCI could be reduced by omitting aspirin and without an increased risk of CV events. “However, the efficacy and safety of this strategy has not been proven in randomized trials,” continued the ESC in the release.
Natsuaki and colleagues conducted the randomized, open-label trial to examine the safety and efficacy of aspirin-free prasugrel monotherapy compared with 1-month DAPT with aspirin and prasugrel in patients with acute coronary syndrome (ACS) or high bleeding risk (HBR) undergoing PCI with cobalt-chromium everolimus-eluting stents, according to the ESC.
Researchers included patients with ACS or HBR between January 2021 and April 2023 from 72 centers in Japan. Before undergoing PCI, participants were randomly assigned in a 1:1 fashion to either prasugrel monotherapy (3.75 mg/day) or DAPT with aspirin (81-100 mg/day) and prasugrel. Both groups received a loading dose of prasugrel 20 mg, noted the ESC.
The 2 primary endpoints were major bleeding events—defined for the purpose of the study as Bleeding Academic Research Consortium type 3 or 5 (for superiority) and a composite CV endpoint of CV death, myocardial infarction, stent thrombosis, stroke (for noninferiority), both at 1 month.
The major secondary endpoint was a composite of the 2 primary endpoints at 1 month representing net clinical benefit, added the ESC.
A total of 5966 patients (mean age, 71.6 years; 23.6% women) were enrolled in the study, with 2984 in the no-aspirin group and 2982 in the DAPT group, according to the release.
Investigators observed that at 1 month, the cumulative incidence of major bleeding was 4.47% in the no-aspirin group and 4.71% in the DAPT group (hazard ratio [HR] 0.95, 95% CI 0.75-1.20; P for superiority=.6). The cumulative incidence of the composite CV endpoint was 4.12% in the no-aspirin group and 3.69% in the DAPT group (HR 1.12, 95% CI 0.87-1.45; P for noninferiority=.01).
There was no between-group difference in the incidence of all-cause mortality (2.28% vs 2.11%). The major secondary endpoint occurred in 7.14% of patients in the no-aspirin group and 7.38% of patients in the DAPT group, “with no between-group difference, indicating a similar effect on net clinical benefit for both groups,” said the ESC.
Investigators noted an excess of any coronary revascularization (1.15% vs 0.57%) and definite or probable stent thrombosis (0.71% vs 0.44%) in the no-aspirin group compared with the DAPT group, while definite stent thrombosis was not different between the 2 arms (0.47% vs 0.37%).
In results from a subgroup analysis stratified by ACS and non-ACS, the excess risk of CV events in the no-aspirin group compared with the DAPT group was seen in participants with ACS, but not in those without ACS.
“Aspirin used for a limited period of 1 month after PCI as a component of DAPT might have exerted a protective effect on vulnerable coronary lesions, particularly in patients with ACS, without a large increase in major bleeding,” concluded Natsuaki. “DAPT should remain the standard strategy for PCI even in the new-generation drug-eluting stent era.”
Source: Dual-antiplatelet therapy should remain standard strategy after stent implantation. European Society of Cardiology. News release. August 26, 2023. Accessed August 29, 2023. https://www.escardio.org/The-ESC/Press-Office/Press-releases/Dual-antiplatelet-therapy-should-remain-standard-strategy-after-stent-implantation