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.