Aspirin + Clopidogrel Post-CABG Improve Overall Bypass Graft Patency

SAN FRANCISCO, CA—The immediate post-operative addition of clopidogrel to aspirin after coronary artery bypass grafting (CABG) proved to be safe and improved overall graft patency, according to data presented at ACC.13, the American College of Cardiology's 62nd Annual Scientific Session.

Improved survival, graft patency, and reduced ischemic events have been observed with the use of aspirin immediately after CABG. Conflicting results comparing combination clopidogrel and aspirin therapy vs. aspirin therapy alone after CABG have been reported.

Jack C. Sun, MD, MSc, FRCSC, from the University of Washington in Seattle, WA and colleagues conducted a systematic review and meta-analysis to evaluate the aspirin and clopidogrel combination vs. aspirin alone. 

Two reviewers independently conducted a MEDLINE and PubMed search for both English and non-English randomized controlled trials studying combination clopidogrel and aspirin therapy, to aspirin therapy alone after CABG. The primary endpoint for this study was graft patency, and safety was measured using incidence of bleeding events.

Researchers chose four randomized controlled trials consisting of 761 patients (n= 380 clopidogrel and aspirin, n=381 aspirin alone), of which only 638 (89.8%) had follow-up imaging of 2,252 bypass grafts to check for patency. Follow-up imaging was conducted at 50–365 days after surgery.

Improved overall graft patency was seen for patients receiving both clopidogrel and aspirin vs. aspirin alone (OR 1.58 [1.13, 2.21]). A significant reduction in saphenous vein graft failure (OR 1.68 [1.16, 2.43]) occurred with clopidogrel, but not for internal mammary arteries or radial artery graft. Total bleeding events in both groups did not differ (0.92 [0.44, 1.92]).

Dr. Sun concluded that the addition of clopidogrel to aspirin is safe immediately following CABG, and that it is “driven by reduction in saphenous vein graft failure.”