Timing Strategy of Preoperative Aspirin and Its Impact on Early Outcomes in Patients Undergoing Coronary Artery Bypass Grafting: A Propensity Score Matching Analysis

Impact of aspirin on bleeding and blood product usage in off‐pump and on‐pump coronary artery bypass graft surgery

“…These differences are more pronounced in comparison to aspirin‐discontinued patients than in comparison to controls given the greater intensity and frequency of blood product usage and increased bleeding not seen in control comparisons. Such findings in OPCABG contradict published works [9–12], but these studies have significant limitations including: small study sizes (< 25 per group) [9], comparator groups being confounded by patients taking clopidogrel and warfarin within < 7 days of surgery [9], ambiguous group definitions with it being unclear if the comparators were acting more like an aspirin discontinuation group (stopping 5–7 days prior) or a control group (stopping antiplatelet > 7 days prior) [10, 11], failure to assess administration of platelets or cryoprecipitate, intraoperative product administration or changes in haematological parameters following surgery [10], no measurement of mean differences in product administration [11], lack of outcome measures assessing bleeding or blood product usage [12] and lack of comparison to previous guideline discontinuation protocols (stopping 5–7 days prior) [12]. We believe our study includes a more robust assessment of bleeding and blood product usage and better defines comparator groups therefore better describing the effects of continuing aspirin prior to OPCABG.…”

“…Both studies also lacked data on continuing aspirin prior to off-pump CABG (OPCABG): only 3% of cases in Myles et al were OPCABG [6] with no OPCABG sub-group testing by Hastings et al due to small numbers [7]. Other studies have reported the effect of continuing aspirin until the day of OPCABG, but these too have important limitations including small sample sizes, ambiguous or lack of comparator groups and lack of information on bleeding and blood product use [9][10][11][12].…”

“…This study addresses these limitations [9][10][11][12] and better assesses the true in vivo effects of continuing aspirin having eliminated the confounding effects of cardiopulmonary by-pass (CPB) including high-dose heparin, loss of large von-Willebrand Factor (VWF) multimers [13], hypothermia-induced coagulopathy [14][15][16][17] and protamine-induced platelet dysfunction [18] via OPCABG analyses. As all included aspirin patients had an indication for therapy prior to surgery, our study population better represents patients taking aspirin prior to CABG as patients included in Myles et al [6] and Hastings et al [7] had no history of aspirin use prior to surgery.…”

“…due to small numbers [ 7 ]. Other studies have reported the effect of continuing aspirin until the day of OPCABG, but these too have important limitations including small sample sizes, ambiguous or lack of comparator groups and lack of information on bleeding and blood product use [ 9 , 10 , 11 , 12 ].…”

Point-of-Care Platelet Function Monitoring: Implications for Patients With Platelet Inhibitors in Cardiac Surgery

“…A more recent retrospective propensity score analysis suggested that discontinuing aspirin before CABG surgery might increase mortality and major thromboembolic events by more than 50%. 22 In contrast, the largest RCT, the Aspirin and Tranexamic Acid for Coronary Artery Surgery (ATACAS) trial, including 2,100 CABG patients, found no benefit of continued aspirin administration regarding mortality, myocardial infarction, and stroke within 30 days and 1 year after surgery. 23,24 Further, the 2017 meta-analysis found a slightly higher rate of RBC transfusion in patients with continued aspirin administration but no difference in chest drainage output or incidence of repeat thoracotomy.…”