Eight RCTs (3,702 participants, 6,898 grafts) were included in the review. One trial had 2,203 participants; others ranged from 110 to 401 participants. Six trials reported that outcome events committees were blinded to treatment group. Six trials reported intention-to-treat data; one trial reported no crossovers.
Compared with on-pump coronary artery bypass graft (CABG), off-pump CABG was associated with an increase in overall graft occlusion (RR 1.32, 95% CI 1.18 to1.48; no significant heterogeneity, p=0.20). Exclusion of any single trial did not significantly alter the results.
In subgroup analyses, an increase in saphenous vein graft occlusion was associated with off-pump CABG, compared with on-pump CABG (RR 1.37, 95% CI 1.22 to 1.55; no significant heterogeneity, p=0.95); there was no effect for internal thoracic artery grafts.