Flow capacity of skeletonized versus pedicled internal thoracic artery in coronary artery bypass graft surgery: systematic review, meta-analysis and meta-regression

Many surgeons are concerned about the flow capacity of a skeletonized internal thoracic artery (ITA) in comparison with a pedicled ITA used during coronary artery bypass graft (CABG). This work aims to summarize the evidence comparing the flow capacity of a skeletonized versus pedicled ITA during CABG. We performed systematic review and meta-analysis according to the PRISMA statement based on a search in MEDLINE, EMBASE, CENTRAL/CCTR, ClinicalTrials.gov, SciELO, LILACS, Google Scholar and reference lists of relevant articles. Studies included were original studies whose populations comprised patients undergoing CABG; compared outcomes between skeletonized versus pedicled ITA; the outcomes included data regarding intraoperative flow capacity of the grafts; the studies were prospective or retrospective or non-randomized or randomized controlled trials. In total, eight studies were identified and reviewed for eligibility and data were extracted. Forest plots and the summarized difference in means including 95% confidence intervals (CIs) were estimated and meta-regressions were performed. There was a statistically significant difference in favour of the skeletonized ITA compared with the pedicled ITA in terms of flow capacity (random-effect model: additional 20.8 ml/min, 95% CI 6.6-35.0, P = 0.004), being the summary measures under the influence of heterogeneity of the effects, but free from publication bias. We observed a difference with regard to the type of study, since non-randomized studies together demonstrated the superiority of a skeletonized ITA (random-effect model: additional 32.3 ml/min, 95% CI 21.0-43.6, P < 0.001), but the randomized studies together did not show it (random-effect model: additional 13.2 ml/min, 95% CI -1.1 to 27.6, P = 0.071). Meta-regression demonstrated some modulation influence by female gender, age and diabetes on the flow capacity of grafts. In summary, in terms of flow capacity, a skeletonized ITA appears to be superior in comparison with a pedicled ITA during CABG.