Effects of Antifibrinolytics on Bleeding and Transfusion Outcomes in Patients Receiving Coronary Artery Bypass Surgery With Preoperative Clopidogrel Exposure

The use of platelet aggregation inhibitors, including aspirin and clopidogrel(CPDG), has become a standard management strategy for patients with acute coronary syndrome. On this background, an increasing percentage of patients presenting for surgical coronary revascularization is the subject to irreversible platelet inhibition.

Investigations on the effect of antiplatelet treatment on postoperative bleeding after cardiac surgery have shown that patients treated with antiplatelet agents until surgery have increased postoperative bleeding, and also an increased need for transfusions of blood products. As a result of the antiplatelet effect of clopidogrel, the frequency of serious bleeding complications has increased significantly, as seen in patients requiring coronary artery bypass grafting(CABG), especially when they received clopidogrel until surgery.

Tranexamic acid(TA) is a widely used antifibrinolytic agent, and is a promising substitute for aprotinin when the latter has seceded in 2007.The release of plasmin during cardiopulmonary bypass(CPB) activates fibrinolysis and may contribute to platelet dysfunction. Pharmacological inhibition of the fibrinolytic system may therefore ameliorate platelet dysfunction and fibrinolysis after CPB and decrease postoperative bleeding. Tranexamic acid prevents plasmin formation and inhibits fibrinolysis.

Concerning the cessation of aprotinin and the increasing proportion of patients with persistence on clopidogrel until their surgery, evolutional work is expected, especially in the eastern population.

The purpose of this study is to assess the effect of tranexamic acid in patients with clopidogrel and asprin ingestion until surgery. The investigators working hypothesis was that tranexamic acid would lower postoperative blood loss and transfusion requirements in these patients and would attenuate bleeding complication of antiplatelet therapy.