Continuation of Dual Antiplatelet Therapy Beyond 12 Months Versus Early De-escalation to Aspirin Monotherapy at Discharge After Percutaneous Coronary Intervention for Acute Coronary Syndrome: Associations With Bleeding, Cardiac Function, and Clinical Outcomes

Abstract

Background: In patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI), antiplatelet decisions after discharge are frequently individualized. Real-world data comparing clinician-guided prolonged clopidogrel-based dual antiplatelet therapy (DAPT) beyond 12 months with early de-escalation to aspirin monotherapy, and their associations with bleeding, transfusion, cardiac autonomic recovery, cardiac function, biomarkers, and major adverse cardiovascular events (MACE), remain limited. We therefore sought to characterize the safety and short-term clinical and physiological correlates of these two discharge strategies in routine ACS practice. Methods: This single-center retrospective cohort study enrolled patients with ACS undergoing PCI between January 2021 and December 2023. All patients received in-hospital DAPT and were discharged to either prolonged DAPT beyond 12 months or early de-escalation to aspirin monotherapy. Bleeding was classified using International Society on Thrombosis and Haemostasis (ISTH) and Bleeding Academic Research Consortium (BARC) criteria. Cardiac autonomic function, echocardiography, and biomarkers were assessed at baseline and 6 months, and major adverse cardiovascular events were recorded over 12 months. Results: A total of 148 ACS patients were included; 74 were discharged to prolonged DAPT beyond 12 months and 74 to early de-escalation to aspirin monotherapy. Older age, lower baseline hemoglobin, higher American Society of Anesthesiologists (ASA) physical status grade, and percutaneous coronary intervention duration greater than 120 minutes were associated with bleeding and or transfusion risk. At 6 months, prolonged DAPT was 3 associated with greater improvements in heart rate variability indices, left ventricular ejection fraction, left ventricular end diastolic diameter, E/e′, N terminal pro B type natriuretic peptide, and soluble suppression of tumorigenicity 2. Total 12 month MACEs were lower with prolonged DAPT (6/74 [8.1%] vs 15/74 [20.3%], P = 0.034), driven mainly by fewer heart failure rehospitalizations (2 vs 8, P = 0.049). Conclusion: Prolonged clopidogrel-based DAPT beyond 12 months was associated with a lower 12-month incidence of MACE. Major bleeding and transfusion events were uncommon in both groups, and estimates for clinical events should be interpreted cautiously given nonrandomized treatment selection and low event counts. These findings are hypothesis generating and warrant confirmation in larger, multicenter prospective studies with longer follow-up.