Antiplatelet therapy and coronary artery bypass graft surgery: perioperative safety and efficacy

Background: Antiplatelet therapy is critical in the management of coronary artery disease. For patients undergoing coronary artery bypass graft surgery (CABG), controversy remains regarding the safety of preoperative antiplatelet therapy and the optimal postoperative antiplatelet regimen to maintain graft patency and reduce ischemic complications. Objective: The goal of this systematic review is to evaluate the risks and benefits of preoperative aspirin and clopidogrel therapy, to identify the optimal timing and dose of aspirin following CABG, and to assess the role of postoperative clopidogrel therapy. Methods: A systematic review was performed to retrieve relevant articles from the Medline database published between 1978 and 2008. Results: With respect to aspirin, the published data suggest that it should be held for 7 - 10 days preoperatively in patients undergoing elective CABG. However, in the current era of routine antifibrinolytic therapy and the high prevalence of patients with extensive atherosclerotic disease, this practice has been put into question. Clopidogrel should be held for at least 5 days before CABG to avoid perioperative bleeding complications. Following surgery, extensive evidence supports the use of aspirin, in doses of 100 - 325 mg daily, to be administered in 48 h postoperatively and continued indefinitely. Less is known regarding the use of clopidogrel following CABG, although it is now recommended as postoperative antiplatelet therapy in patients with recent acute coronary syndromes. Conclusion: Despite > 30 years of experience with antiplatelet agents during CABG, questions remain regarding their perioperative safety and efficacy. The results of continuing randomized controlled trials should further clarify the role of perioperative aspirin and clopidogrel therapy and help redefine the modern antiplatelet management of coronary artery bypass patients.