Comparison of dual antiplatelet therapies after coronary endarterectomy combined with coronary artery bypass grafting: a cohort study

BACKGROUND: Coronary endarterectomy (CE) combined with coronary artery bypass grafting (CABG) can be the only option for complete revascularization in some patients with diffuse coronary artery disease. Unfortunately, CE can cause the lack of endothelium, resulting in increased risk of thrombotic events. Therefore, antithrombotic therapy is very important after surgery. However, there’s no consistent protocol exists till now. The aim of this study was to compare the effectiveness and safety of dual antiplatelet therapies (DAPT) including aspirin plus clopidogrel (AC) or ticagrelor (AT) after CE + CABG. METHOD: A total of 137 continuous patients (mean age 60.0 ± 9.0 years) underwent CE + CABG from January 2016 to July 2018 in our center, and patients who received dual antiplatelet therapy (DAPT) after surgery (n = 121) were included in this study. All of the patients received aspirin 100 mg daily therapy after surgery, and 67 of the patients received extra clopidogrel 75 mg (AC) daily therapy, whereas 54 received extra ticagrelor 90 mg (AT) twice daily. All patients continued aspirin monotherapy after 1 year. Occurrence of ischemic events and bleeding events between two groups were compared. Kaplan-Meier survival was used to compare freedom from major adverse cardiovascular and cerebrovascular events (MACCE) between two groups, and log-rank test was used to confirm statistical difference. RESULTS: Follow-up was completed by 99.2%, and median follow-up time was 30.0(22.5, 35.2) months. No operative death was observed, while perioperative myocardial infarction was observed in 2(1.7%) patients (AC 1.5% vs. AT 1.9%, p = ns). One patient in AC group suffered from cardiac tamponade. During the follow-up period, no death was observed. Ischemic events including nonfatal myocardial infarction, repeat revascularization and ischemic stroke were observed in 6(5.0%) patients (AC 4.5% vs. AT 5.6%, p = ns). Overt bleeding had occurred in 3(2.5%) patients (AC 3.0% vs. AT 1.9%, p = ns). Kaplan-Meier analysis indicated that MACCE-free survival of the two groups at 3 years was 97.0% in the AC group versus 94.1% in the AT group (p = ns). CONCLUSION: In patients undergoing CE + CABG, DAPT therapy can be effective and safe with comparable results between AC and AT therapy in terms of ischemic and bleeding events. Further studies are needed.