Antiplatelet therapy for patients undergoing coronary artery bypass surgery

Abstract

Considerable variation in the use and duration of antiplatelet medications during the perioperative and postoperative care of patients undergoing coronary artery bypass grafting (CABG) reflects the limited number of studies focused directly on these patients as well as the variation in the results reported. In this review we highlight the incidence and mechanisms of graft closure as well as the evidence in support of antiplatelet therapy that is balanced by the impact of antiplatelet therapy on the risk of bleeding to provide recommendations for the use of this therapy in patients undergoing CABG. Low-dose acetylsalicylic acid (ASA; ≤ 160 mg daily) reduces the incidence of perioperative myocardial infarction, acute renal injury, and mortality without increasing the risk of bleeding and so is recommended both before and after CABG. The use of dual antiplatelet therapy with ASA plus a P2Y12 antagonist adds a greater risk of bleeding. While additional studies are required, we can make the following recommendations: because of increased bleeding and mortality when patients are treated with clopidogrel preoperatively, CABG should be delayed for five days. Because of increased bleeding when patients are treated with ticagrelor preoperatively, CABG should be delayed for three days. Because of increased bleeding when patients are treated with prasugrel preopera­tively, CABG should be delayed for seven days. For patients who had a coronary stent placed preoperatively or had an acute coronary syndrome preoperatively, resumption of therapy with their P2Y12 antagonist postoperatively for 12 months reduces the subsequent incidence of cardiovascular events.