Effects of Low Dose Aspirin Pre-treatment on Platelet Activation Undergoing Off-pump Coronary Artery Bypass Surgery

Effects of Low Dose Aspirin Pre-treatment on Platelet Activation Undergoing Off-pump Coronary Artery Bypass Surgery

Platelet activation after off pump coronary artery bypass (OPCAB) surgery may affect thrombus formation. The purpose of this study is to assess the effects of preoperative continuation of aspirin on platelet activation after off pump coronary artery bypass surgery.

Patients undergoing OPCAB surgery will be randomized to continue preoperative aspirin or discontinue aspirin before surgery.

Platelet activation can be evaluated by measuring platelet p-selectin using flowcytometry. In this study, we will compare platelet-activated markers and conventional coagulation tests.

Inclusion Criteria:

• age : 20-80
• elective OPCAB
• informed consent

Exclusion Criteria:

• coagulation disorder
• emergency operation, re-operation
• co-existing valvular disease
• less than 6 months after cerebral vascular accident
• heparin induced thrombocytopenia
• heparin resistance
• menstrual phase
• preoperative cardiopulmonary bypass, continuous veno-veno hemofiltration, intra-aortic balloon pump application
• less than 12 months after myocardiac infarction
• less than 10 days after unstable angina
• less than 30 days after percutaneous coronary intervention
• less than 6 wks after bare metal stent insertion
• less than 12 months after drug eluting stent insertion