Preoperative aspirin therapy is associated with improved postoperative outcomes in patients undergoing coronary artery bypass grafting

Background - Aspirin is beneficial in the setting of atherosclerotic cardiovascular disease. There are limited data evaluating preoperative aspirin administration preceding coronary artery bypass grafting and associated postoperative outcomes. Methods and Results - Using prospectively collected data from 1636 consecutive patients undergoing first-time isolated coronary artery bypass surgery at our institution from January 2000 through December 2002, we evaluated the association between aspirin usage within the 5 days preceding coronary bypass surgery and risk of adverse in-hospital postoperative events. A logistic regression model, which included propensity scores, was used to adjust for remaining differences between groups. Overall, there were 36 deaths (2.2%) and 48 adverse cerebrovascular events (2.9%) in the postoperative hospitalization period. Patients receiving preoperative aspirin (n=1316) had significantly lower postoperative in-hospital mortality compared with those not receiving preoperative aspirin [1.7% versus 4.4%; adjusted odds ratio (OR), 0.34; 95% CI, 0.15 to 0.75; P=0.007]. Rates of postoperative cerebrovascular events were similar between groups (2.7% versus 3.8%; adjusted OR, 0.67; 95% CI, 0.32 to 1.50; P=0.31). Preoperative aspirin therapy was not associated with an increased risk of reoperation for bleeding (3.5% versus 3.4%; P=0.96) or requirement for postoperative blood product transfusion (adjusted OR, 1.17; 95% CI, 0.88 to 1.54; P=0.28). Conclusions - Aspirin usage within the 5 days preceding coronary artery bypass surgery is associated with a lower risk of postoperative in-hospital mortality and appears to be safe without an associated increased risk of reoperation for bleeding or need for blood product transfusion.