Forty-one RCTs (n=3,996) were included.
The randomisation method was not described in 24 of the 41 RCTs and only 12 concealed the treatment allocation.
Compared with on-pump surgery, off-pump CABG was associated with a statistically significant reduction in the risk of stroke (RR 0.50, 95% CI: 0.07, 0.73), representing 10 fewer strokes per 1,000 CABG patients (27 RCTs, n=3,062), atrial fibrillation (RR 0.30, 95% CI: 0.16, 0.43) and wound infection (RR 0.48, 95% CI: 0.26, 0.63). It was also associated with a statistically non significant reduction in the risk of renal failure and myocardial infarction, and a statistically non significant increase in the risk of re-intervention. There was no statistically significant difference in mortality or angina recurrence.
There was increased crossover from off-pump to on-pump CABG (RR 3.82, 95% CI: 2.12, 6.88), representing 50 additional crossovers from off-pump to on-pump CABG (23 RCTs, n=2,804).
Off-pump CABG was associated with a statistically significant reduction in the number of distal grafts compared with on-pump surgery (weighted mean difference -0.27 per patient, 95% CI: 0.37, 0.17; 29 RCTs, n=2,457); significant heterogeneity was found (p<0.00001; I-squared 69.6%).
Funnel plots showed no evidence of publication bias.