No improvement in neurocognitive outcomes after off-pump versus on-pump coronary revascularisation: a meta-analysis

The popularity of off-pump (beating heart) coronary artery bypass grafting (CABG) was initially stimulated by numerous theoretical benefits including lower incidence of stroke and neurocognitive dysfunction. With a postoperative stroke rate of less than 1% for elective CABG, it has been very difficult to demonstrate any significant differences in this outcome between techniques. However, changes in neurocognitive function are more common in the postoperative setting and thus provide greater power for demonstrating improvement with changes in surgical technique. The aim of this meta-analysis was to assess whether there were significant differences in neurocognitive outcomes in patients after undergoing off-pump versus on-pump CABG. A database search for prospective randomised controlled trials of off-pump versus on-pump CABG in any language was conducted. Eight trials incorporating 892 patients fulfilled all the inclusion criteria for reporting of neurocognitive outcomes, and were able to be included in this meta-analysis. Sufficient data were available across the seven studies to combine results for five neurocognitive tests (Rey Auditory Verbal Learning, Grooved Pegboard, Trail A and B, and Digit Symbol). Overall there were no convincing differences in outcomes in neurocognitive testing between off-pump and on-pump CABG groups. The results of this meta-analysis show that there are no significant neurocognitive benefits when comparing off-pump versus on-pump CABG.