Coronary artery bypass grafting (CABG)-related bleeding complications and perioperative coronary events are strongly influenced by the management of antithrombotic therapy before and after CABG. Bleeding but also blood products transfusion increase the risk of death and compromise the long-term benefits of CABG.1 The use of new P2Y12 inhibitors, increasing pre-CABG percutaneous coronary interventions (PCI) with drug eluting stents (DES) requiring specific antiplatelet regimens, and advances in surgical technique has prompted the ESC Working Group on Cardiovascular Surgery and the ESC Working Group on Thrombosis to review the evidence of peri-CABG recommendations on antithrombotic management. Due to the paucity of randomized trials, most of the evidence is still derived from observational studies and expert consensus, further reinforcing the importance of a multidisciplinary consultation for optimal decision making. ### Benefits of preoperative aspirin Aspirin (acetylsalicylic acid, ASA) is recommended as secondary prevention therapy for all patients with proven coronary artery disease (CAD) and without contraindications. Its indication is even stronger for post-CABG patients (recommendation IA).2 The general consensus is that ASA treatment withdrawal has ominous prognostic implications in patients with CAD, especially in those with intracoronary stents, and should be advocated only when the bleeding risk clearly outweighs that of atherothrombotic events.3 The benefits of continuing ASA until the day of CABG (‘preoperative ASA’) are less clear and may explain the wide variability in the management of ASA therapy in the perioperative period and differences between guidelines endorsed by different professional and scientific societies (Supplementary material online, Table S1 ). This was based on the demonstration that ASA started the day before surgery was no more effective than ASA started 6 h after surgery at improving early (7- to 10-day) graft patency, but was associated with increased bleeding complications.4 More recent evidence suggests, however, that ASA use within 5–7 days prior to CABG …