Perioperative Bleeding in Patients With Acute Coronary Syndrome Treated With Fondaparinux Versus Low-Molecular-Weight Heparin Before Coronary Artery Bypass Grafting

{The perioperative bleeding risk in patients receiving fondaparinux versus low-molecular weight heparin before coronary artery bypass grafting has not been reported. We evaluated perioperative coronary artery bypass grafting-related bleeding in patients with acute coronary syndrome preoperatively treated with fondaparinux or low-molecular weight heparin. All patients with acute coronary syndrome from the prospective, European multicenter registry on coronary artery bypass grafting preoperatively treated with fondaparinux or low-molecular weight heparin undergoing isolated primary CABG were eligible. The primary outcome measure was severe or massive bleeding defined according to the Universal Definition of Perioperative Bleeding stratified by P2Y(12) inhibitor discontinuation. Secondary outcome measures included 3 additional definitions of major bleeding used in cardiac surgery trials. Propensity score matching was performed to adjust for differences in pre- and perioperative covariates. 1,525 patients were included, of whom 276 (18.1%) received fondaparinux and 1,249 (81.9%) low-molecular weight heparin preoperatively. In the propensity score-matched cohort (245 pairs), the risk of major bleeding according to the universal definition of perioperative bleeding severe or massive bleeding (11.8 vs 9.0%