Clinical Significance of Platelet Reactivity on Clopidogrel During Off-pump Coronary Artery Bypass

Objective: To evaluate the early and late prognoses of patients according to platelet reactivity after clopidogrel administration and determine whether the measurement of platelet inhibition predicted 1-year clinical outcomes after off-pump coronary bypass (OPCAB) Study design

• Prospective, observational, single-center study
• Subjects with OPCAB surgery who meet all inclusion and exclusion criteria will be enrolled.
• Platelet reactivity after 7-days clopidogrel treatment from the day of surgery will be measured by VerifyNow system.
• Dual antiplatelet therapy including aspirin and clopidogrel will be administered for 1 year after surgery and subjects will be followed-up for 1 year about primary endpoint.
• Cutoff value of P2Y12 reactivity units (PRUs) for primary endpoint will be assessed and the cohort will be divided by the PRU cutoff value (low/high platelet reactivity groups).
• The primary and secondary endpoints will be compared between two groups

Inclusion Criteria:

• Patients with indications for surgical myocardial revascularization
• Patients who undergo off-pump coronary artery bypass
• Age between 19~80 years
• Patients with signed informed consent

Exclusion Criteria:

• Patients with combined surgery with coronary bypass grafting
• On-pump conversion
• Patients with moderate renal dysfunction (creatinine>2.0mg/dl) or need for dialysis
• Patients with chronic treatment with proton pump inhibitors
• Patients with preoperative bleeding
• Thrombocytopenia (Platelet count 70,000/ml)
• Re-do surgery
• Early death before the measurement of platelet reactivity