Cardiac catheterization through the radial artery approach (RA) has been shown to significantly reduce access-site complications compared with the femoral artery approach (FA) in many clinical settings. However, in the subset of patients with previous coronary artery bypass grafting (CABG), optimal vascular access site for coronary angiography and intervention is stilt a matter of debate. We aimed to perform a systematic review and meta analysis of available studies comparing RA with FA in patients with previous CABG. Data were extracted by two independent reviewers; weighted mean differences and 95% confidence interval (CI) were calculated for continuous outcomes, whereas odds ratio (OR) and 95% CI were calculated for dichotomous outcomes. Summary statistics were calculated by random-effects model using Review Manager 5.3 software. The meta-analysis included 1 randomized and 8 nonrandomized studies, with a total of 2,763 patients. Compared with FA, RA required similar procedural time (mean difference 3.24 minutes, 95% CI -1.76 to 8.25, p = 0.20), fluoroscopy time (mean difference 0.62 minutes, 95% CI -0.83 to 2.07, p = 0.40), and contrast volume (mean difference -2.58 ml, 95% CI -18.36 to 13.20, p = 0.75) and was associated with similar rate of procedural failure (OR 1.32, 95% CI 0.63 to 2.80, p = 0.46), higher rate of crossover to another vascular access (OR 7.0, 95% CI 2.74 to 17.87, p <0.0001), and lower risk of access-site complications (OR 0.46, 95%CI 0.26 to 0.80, p = 0.006). In conclusion, the present meta-analysis suggests that in patients with previous CABG undergoing coronary procedures, RA, compared with FA, is associated with increased crossover rate but may reduce access-site complications. (C) 2016 Elsevier Inc. All rights reserved.