A systematic review of randomized trials comparing revascularization rate and graft patency of off-pump and conventional coronary surgery

ObjectiveAlthough many trials have been conducted to evaluate the benefits of off-pump coronary surgery, few have concentrated on graft patency. We sought to evaluate the impact of off-pump surgery on completeness of revascularization and graft patency compared with conventional surgery.MethodsA systematic literature search was undertaken of all randomized trials of off-pump coronary surgery in MEDLINE, EMBASE, the Cochrane Library Controlled Trials Register, the National Research Register, and abstracts from major conferences.ResultsIn total, 132 publications were identified. From this number, we excluded 43 without a conventional surgery arm and 80 that did not evaluate graft patency. One trial was excluded for selective angiography and one abstract was excluded because of insufficient information. A total of 7 trials were eligible for overview. On initial analysis, the relative risk of graft patency in off-pump coronary surgery compared with conventional surgery was 0.959 (95% confidence interval 0.936-0.983; P = .001). The analysis was repeated after excluding one specific trial because of clinical and statistical heterogeneity (χ26 = 27.78; P < .001), and a relative risk of 0.953 (95% confidence interval 0.927-0.980; P = .001) was obtained with no further evidence of heterogeneity (χ25 = 5.35; P = .374). In 5 trials that included the mean number of grafts performed per arm, the standardized mean difference in revascularization comparing off-pump with conventional surgery was −0.164 (−0.286 to −0.043; P = .008).ConclusionIn a meta-analysis of randomized trials, patients undergoing off-pump coronary surgery had a lower rate of revascularization and lower graft patency than did patients undergoing conventional coronary surgery.