Combined antiplatelet therapy with aspirin and clopidogrel (or an alternative P2Y12 receptor blocker) is standard of care in patients with acute coronary syndromes1-3 and after percutaneous coronary intervention4-6 because it reduces myocardial infarction and death related to coronary thrombosis. Such patients commonly present for urgent and emergent CABG, where dual antiplatelet therapy is associated with a 2-fold increase in risk of blood transfusion, 5-fold increase in risk of reoperation, and 50% increase in risk of wound infection.7,8 Balancing these thrombotic and bleeding risks is critical when deciding to continue or withdraw antiplatelet agents in patients who require surgery. In the absence of randomized clinical trials that compare both strategies head to head, clinicians are forced to rely on evidence from observational studies and expert opinion to guide therapy. The current consensus recommendation from multiple expert panels is to continue aspirin therapy but withhold clopidogrel for 5 days prior to CABG in the vast majority of cases.9-12 In this issue of JAMA Surgery, Shi et al13 suggest that withdrawal of clopidogrel may not be necessary if prophylactic tranexamic acid is administered; however, this assertion should be met with skepticism. The Shi et al study can be viewed as 2 separate analyses. In the prospective cohort analysis, they nicely demonstrate that exposure to clopidogrel before CABG is associated with increased bleeding and transfusion, with morbidity highest in those exposed within 7 days of surgery, intermediate in those exposed more than 7 days before surgery, and lowest in those not exposed. In the randomized clinical trial portion, Shi et al randomize patients to tranexamic acid or placebo using a stratified block design based on preoperative clopidogrel exposure and nicely show that antifibrinolytic treatment reduces bleeding and transfusion overall and in each clopidogrel-exposure strata. The data do not suggest differential efficacy of tranexamic acid and interaction models that support such a claim are not presented. This claim derives from the analysis by Shi et al of subgroups from the cohort study, which is prone to bias due to lack of randomization to clopidogrel exposure. Although it certainly may be reasonable to continue dual antiplatelet therapy in some individuals at particularly high thrombotic risk prior to CABG, the Shi et al study does not provide robust evidence on this issue. Adherence to current consensus recommendations seems more prudent. Back to top Article Information Correspondence: Dr Faraday, Department of Anesthesiology/Critical Care Medicine and Surgery, Johns Hopkins University School of Medicine, 600 N Wolfe St, Meyer 298, Baltimore, MD 21287 ([email protected]). Published Online: February 20, 2013. doi:10.1001/jamasurg.2013.1571 Conflict of Interest Disclosures: None reported. References 1. Yusuf S, Zhao F, Mehta SR, Chrolavicius S, Tognoni G, Fox KK.Clopidogrel in Unstable Angina to Prevent Recurrent Events Trial Investigators. Effects of clopidogrel in addition to aspirin in patients with acute coronary syndromes without ST-segment elevation. N Engl J Med. 2001;345(7):494-50211519503PubMedGoogle ScholarCrossref 2. Sabatine MS, Cannon CP, Gibson CM, et al; CLARITY-TIMI 28 Investigators. Addition of clopidogrel to aspirin and fibrinolytic therapy for myocardial infarction with ST-segment elevation. N Engl J Med. 2005;352(12):1179-118915758000PubMedGoogle ScholarCrossref 3. 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