Dual Antiplatelet Therapy Duration in Medically Managed Acute Coronary Syndrome Patients: Sub-Analysis of the OPT-CAD Study.

Ma, Sicong; Jiang, Zaixin; Qiu, Miaohan; Li, Zhiguo; Bian, Liya; Li, Yi; Han, Yaling

INTRODUCTION Optimal dual antiplatelet therapy (DAPT) duration for medically managed acute coronary syndrome (ACS) (MMACS) patients is still unknown. We explored the efficacy and safety of ≥ 12-month DAPT among MMACS patients. METHODS In this sub-analysis of the optimal antiplatelet therapy for Chinese Patients with Coronary Artery Disease study (NCT01735305), clinical outcomes among MMACS patients were compared between the < 12-month and ≥ 12-month DAPT groups. The primary efficacy endpoint was a composite of cardiac death, myocardial infarction, and stroke. Safety endpoints included the Bleeding Academic Research Consortium (BARC) 2-5, BARC 3-5, and all bleeding events. Propensity score matching (PSM) was used to compare baseline characteristics between the < 12-month and ≥ 12-month DAPT groups. RESULTS In this cohort of ACS patients (n = 10,016), MMACS patients (n = 2967) were less likely to use DAPT at 12 (31.64% vs. 67.47%, P < 0.0001) and 24 (13.82% vs. 18.71%, P < 0.0001) months and experienced more ischemic events at 12 (4.55% vs. 3.40%, P = 0.006) and 24 (6.88% vs. 5.08%, P = 0.0004) months than those treated with percutaneous coronary intervention (n = 7049). Among MMACS patients, the rate of primary efficacy endpoint occurring within the second year was significantly higher in the < 12-month DAPT group than in the ≥ 12-month group both before (2.88% vs. 1.60%, P = 0.040) and after (3.19% vs. 1.71%, P = 0.045) PSM. After PSM, no significant differences in all bleeding, BARC 2-5, and BARC 3-5 bleeding were found between the groups. CONCLUSION MMACS patients with insufficient DAPT management experienced relatively more ischemic events. DAPT for at least 1 year may be beneficial to this special population without significantly increasing the bleeding risks. TRIAL REGISTRATION ClinicalTrials.gov identifier, NCT01735305.