Left internal mammary artery skeletonization reduces bleeding - a randomized controlled trial.

Abstract Background The objective was to compare the impact of skeletonized vs. pedicled left internal mammary artery (LIMA) harvesting on bleeding after coronary artery by-pass grafting (CABG). Methods In a randomized single-blinded trial with parallel group design and equal allocation, we randomly assigned 62 patients undergoing primary elective CABG in a tertiary cardiac center to skeletonized or pedicled LIMA dissection. Preoperatively, all aspects of coagulation were assessed. Patients were blinded to LIMA dissection technique and monitored for cumulative drainage at 12h (primary outcome) and myocardial necrosis markers. Results With recruitment complete, there were 31 patients in each group and all patients were analyzed. Median postoperative drainage was 395 ml at 12h in all patients, and was lower by 28% at 12h (p=0.02) in patients with skeletonized LIMA (Cohen's d [95% CI], 0.6 [0.09-1.11]). Patients with LIMA pedicle received more fresh frozen plasma transfusions than skeletonized LIMA group (3 [3-5] vs. 3 [3-3], p=0.03). Study arms did not differ in blood coagulation. LIMA skeletonization (OR [95% CI], 0.04 [0.003-0.44], p=0.009) and higher body mass index (OR [95% CI], 0.63 [0.45-0.89], p=0.008) decreased the odds of being in the top drainage quartile at 12h (≥550 ml). Creatine kinase was lower in skeletonized LIMA directly after surgery (218 [175-310] vs. 424 [256-510] U/l, p=0.0001), at 6h (324 [239-424] vs. 529 [374-707] U/l, p=0.0003) and 12h postoperatively (351 [277-552] vs. 695 [509-1067] U/l, p=0.0001). Conclusions LIMA skeletonization results in a lower mediastinal drainage after CABG than pedicled LIMA harvesting. Jagiellonian University grant No. K/ZDS/007961. NCT03622671.