ObjectiveTo systematically review the effectiveness and safety of aspirin-clopidogrel combined anti-platelet therapy after coronary artery bypass grafting (CABG). MethodsDatabases including The Cochrane Library (Issue 2, 2013), PubMed, EMbase, CBM, CNKI, WanFang Data and VIP were searched electronically from their inception to September 2013 for randomized controlled trials (RCTs) about aspirin-clopidogrel combined anti-platelet therapy after CABG. Two reviewers selected literature independently according to the inclusion and exclusion criteria. After data extraction and methological quality assessment of the included studies, meta-analysis was performed using RevMan 5.2 software. ResultsA total of six RCTs involving 901 patients were included, of which 449 cases were in the aspirin-clopidogrel group (A+C) and 452 cases were in the aspirin with or without placebo group (A+P). The results of meta-analysis showed that: compared with A+P, A+C significantly reduced occlusion rates of the saphenous vein graft (RR=0.59, 95% CI 0.43 to 0.80, P=0.000 6). But no significant difference was found between the two groups in occlusion rates of the left internal mammary artery graft (RR=0.88, 95% CI 0.35 to 2.18, P=0.78), radial artery graft (RR=0.43, 95% CI 0.13 to 1.46, P=0.18), pleural fluid drainage volume (MD=-1.68, 95%CI-48.69 to 45.32, P=0.94), incidence of major bleeding events (RR=1.20, 95% CI 0.39 to 1.65, P=0.75), major cardiovascular events (OR=0.81, 95% CI 0.38 to 1.72, P=0.58), and mortality within 30 days (RR=0.64, 95% CI 0.17 to 2.44, P=0.52). ConclusionIn reducing occlusion rates of the saphenous vein graft, the A+C group is more effective than the A+P group. Due to the limited quantity and quality of the included studies, the above conclusion still needs to be verified by carrying out more high-quality RCTs.