Impact of extended dual antiplatelet therapy on clinical prognosis in acute coronary syndrome patients with intermediate or high ischemic risk defined by the GRACE score

Objectives To evaluate the impact of extended dual antiplatelet therapy (DAPT) beyond 12 months in acute coronary syndrome (ACS) patients with intermediate-risk to high-risk of developing ischemia according to the Global Acute Coronary Event Registration (GRACE) score. Background The duration of optimal DAPT remains controversial in patients at higher risk of developing ischemia. Methods Overall, 9,309 ACS patients in the Optimal antiPlatelet Therapy for Chinese patients with Coronary Artery Disease (OPT-CAD) study were stratified as low-risk (n = 5,112) or intermediate-risk to high-risk (n = 4,197) according to the GRACE score on hospital discharge. Clinical outcomes at 12-24 months in patients with intermediate-to-high risk who completed 1-year DAPT without any adverse events were analyzed. The primary endpoint was 24-month net adverse clinical events (NACEs). Results Patients at intermediate-to-high-risk had significantly higher incidence of NACE (10.2 vs. 4.9%, p < .01) and ischemic events (8.3 vs. 3.8%, p < .01) than low-risk patients at 24 months. For patients at intermediate-to-high-risk, extended DAPT beyond 12 months was associated with lower risk of NACE (3.0 vs. 5.1%, p = .012), all-cause death (1.1 vs. 2.6%, p = .01), and cardiac death (0.6 vs. 1.8%, p = .01), without excessive risk of major bleeding events (0.3 vs. 0.5%, p = .47). Clinical outcomes in the propensity-matched cohort were consistent. Conclusions ACS patients with intermediate-risk or high-ischemic risk may benefit from extended DAPT beyond 1 year, an outcome than requires further confirmation in large-scale randomized trials.