Abstract 11867: Effects of the Use of Preoperative Aspirin Among Patient Undergoing Cardiac Surgery

Background: Continuing or stopping aspirin prior to coronary artery bypass graft (CABG) surgery remains controversial with a major concern of risk of bleeding, but some studies have shown that aspirin did not increase the risk of bleeding and may be beneficial to be continued until the time of surgery or after surgery. Hypothesis: The preoperative aspirin could have short- and long-term effects on patients with CABG or valve surgery. Methods: Consecutive patients (9584) with cardiac surgery from Thomas Jefferson University hospital, Abington Memorial hospital and UC Davis Medical Center during 2001 to 2015 were included in this study. The preoperative use of aspirin was defined as within 5 days preceding surgery. Patients excluded were those with preoperative anticoagulants (except unfractionated heparin), adenosine diphosphate receptor inhibitors, glycoprotein IIb/IIIa inhibitors, anti-platelets, unknown preoperative aspirin use. Outcomes were analyzed with the use of propensity scores and inverse-probability-weighting adjustment to reduce treatment selection bias. Results: Among 6219 patients met inclusion criteria, 4033 (64.8%) had preoperative aspirin (PreASA) and 2186 (35.0%) didn’t (No-PreASA). The median follow-up period was 3.6 years. At 30 days after surgery, there was significant difference in adjusted mortality between the groups (3.69% in the PreASA group vs. 5.31% in the No-PreASA group; risk ratio, 0.69; 95% confidence interval [CI], 0.59 to 0.84). At 4 years, there was still lower mortality with PreASA than with No-PreASA (15.79% in the PreASA vs. 17.78% in the No-PreASA group; risk ratio, 0.89; 95% CI, 0.86 to 0.92). With the use of different analytic methods and sensitivity analysis to assess residual confounding, similar results were noted in postoperative renal failure (4.02% in the PreASA group vs. 5.81% in the No-PreASA group; odds ratio: 0.74; 95%CI: 0.63-0.88 ) and major adverse cardiocerebral events (10.76% in the PreASA group vs. 14.46% in the No-PreASA group; odds ratio: 0.77; 95%CI: 0.69-0.85). Conclusions: In this observational study, we found that among patients with cardiac surgery, there was a short- and long-term survival advantage among patients who used preoperative aspirin as compared with patients who didn’t.