2224Preoperative dual antiplatelet therapy and early outcomes in patients undergoing coronary artery bypass grafting

Abstract Background Recent evidence suggests that preoperative antiplatelet regimen with aspirin can be safely used for patients scheduled for coronary artery bypass grafting (CABG), aiming to maintain graft patency and reduce ischemic complications at an acceptable bleeding risk. However, little is known regarding the safety and efficacy of preoperative low-dose dual antiplatelet therapy with aspirin combined clopidogrel for CABG patients. Objective To investigate the efficacy and safety of preoperative low-dose dual antiplatelet therapy with aspirin combined clopidogrel for patients receiving elective isolated CABG. Methods We retrospectively reviewed data from patients underwent isolated elective CABG in our single institution from January 2013 to March 2017. Dual antiplatelet therapy was determined as aspirin (100 mg daily) five days and clopidogrel (75 mg daily) three days proximity to the surgery. Propensity score matching was used to generate matched groups from patients taken dual antiplatelet therapy and aspirin alone. The Kaplan–Meier method and the log-rank test were applied to create and examine survival curves. Cox proportional hazards regression was employed to explore the differences in early-term outcomes between the two strategies. The primary outcome was in-hospital major adverse cardiac and cerebrovascular events (MACCEs, including all-cause death, nonfatal MI and nonfatal stroke). The secondary outcomes were perioperative bleeding complications (re-exploration for bleeding and blood products transfusion), and MACCEs at six months after surgery. Results From January 2013 to March 2017, 1102 patients received 100 mg aspirin daily five days prior to CABG, and 295 of them combined clopidogrel (75mg daily). Patients on dual antiplatelet therapy with aspirin combined clopidogrel were more often underwent previously stent implantation (14.2% versus 7.7%), and no significant difference regarding other patient baseline characteristics was observed between the two groups. Propensity score matching created 295 well-matched sets (dual antiplatelet therapy versus aspirin alone). Compared with preoperative aspirin alone, dual antiplatelet therapy was associated with more in-hospital major adverse cardiac and cerebrovascular events (Odds Ratio [OR], 2.59; 95% confidence internal [CI], 1.05–6.39; P=0.039), and also higher rates of perioperative blood products transfusion (47.1% versus 34.6%, OR 1.69, 95% CI, 1.21–2.35, P=0.002). After 6 months' follow-up (median 198 days), there were 25 patients (8.5%) with an event in the dual antiplatelet therapy group and 12 patients (4.1%) with an event in the aspirin alone group (Hazard Ratio [HR], 2.12; 95% CI, 1.06–4.22; P=0.033). MACCEs at 6 months after CABG Conclusions For patients receiving elective isolated CABG, preoperative low-dose dual antiplatelet therapy with aspirin combined clopidogrel may result in increased early major adverse cardiac and cerebrovascular events and more perioperative blood transfusions.