Dual antiplatelet therapy shows no benefit over aspirin after CABG in patients with acute coronary syndrome

Dual antiplatelet therapy (DAPT) was not more effective than aspirin alone for the prevention of major adverse cardiovascular events and increased major bleeding in patients with acute coronary syndrome (ACS) who underwent coronary artery bypass grafting (CABG), according to late-breaking research presented in a Hot Line session today at ESC Congress 20251 and simultaneously published in New England Journal of Medicine.

ESC Guidelines recommend DAPT with aspirin plus a P2Y12 inhibitor over single antiplatelet therapy for patients with ACS (heart attacks or unstable angina) who have undergone CABG.

These recommendations are mainly based on extrapolation of data from non-CABG studies, sub-studies of ACS trials and smaller randomised studies with surrogate endpoints. Data from larger randomised trials with clinically relevant endpoints are lacking. We conducted the TACSI trial to investigate whether 12 months of DAPT with ticagrelor and aspirin would reduce the risk of all-cause death and cardiovascular events compared with aspirin alone in ACS patients after CABG."

Anders Jeppsson, Principal Investigator, Professor from Sahlgrenska University Hospital, Gothenburg, Sweden

The TACSI trial was an investigator-initiated pragmatic, open-label, registry-based randomised trial conducted in all 22 cardiothoracic surgery centres in Sweden, Denmark, Norway, Finland and Iceland. Patients undergoing their first isolated CABG were randomised 1:1 within 3-14 days to either DAPT (ticagrelor 90 mg twice daily plus aspirin 75 mg once daily) or aspirin only (75-160 mg daily according to local protocols) for 12 months. The primary efficacy endpoint of major adverse cardiovascular events (MACE) was a composite of all-cause death, myocardial infarction, stroke or new coronary revascularisation within 12 months. The primary safety endpoint was major bleeding.

The 2,201 patients included had a mean age of 66 years and 14.4% were women. The primary endpoint of MACE occurred in a similar proportion of patients in each group: 4.8% of patients in the DAPT group and 4.6% in the aspirin only group (hazard ratio [HR] 1.09; 95% confidence interval [CI] 0.74 to 1.60; log rank p=0.77). Major bleeding was more frequent in the DAPT group (4.9% vs. 2.0%; HR 2.50; 95% CI 1.52 to 4.11).

A key secondary endpoint of net adverse clinical events (the primary endpoint plus major bleeding) was higher in the DAPT group than in the aspirin group (9.1% vs. 6.4%; HR 1.45; 95% CI 1.07 to 1.97). A total of 0.7% of patients with DAPT and 0.2% with aspirin only died during the first year after randomisation (HR 4.01; 95% CI 0.85 to 18.9).

Concluding, Professor Jeppsson said: "Our 12-month data do not support the use of DAPT over aspirin alone in ACS patients after CABG, given the lack of improvement in MACE and the increased risk of major bleeding. However, further long-term follow-up is needed."