Ultrasonic scalpel versus electrocautery for internal mammary artery harvesting: a meta-analysis

Objective Although an ultrasonic harmonic scalpel (HS) has been used to harvest the internal mammary artery (IMA) for coronary artery bypass grafting, the benefits and risks compared to conventional electrocautery (EC) are not clear. We aimed to compare the outcomes of HS versus EC for IMA harvesting. Methods An electronic search was performed to identify all relevant studies. Baseline characteristics, perioperative variables, and clinical outcomes were extracted and pooled for meta-analysis. Results This meta-analysis included 12 studies. Pooled analyses demonstrated that both groups had comparable preoperative baseline characteristics including age, gender, and left ventricular ejection fraction. HS included more diabetic patients [33% (95% CI 30, 35) vs. 27% (23, 31), p = 0.01]. Harvest time for unilateral IMA was significantly longer with HS than EC [39 (31, 47) minutes vs. 25 (17, 33) minutes, p < 0.01]. However, the rate of pedicled unilateral IMA was significantly higher for EC compared with HS [20% (17, 24) vs. 8% (7, 9), p < 0.01]. The rate of intact endothelium was significantly higher with HS than EC [95% (88, 98) vs. 81% (68, 89), p < 0.01). There was no significant difference in postoperative outcomes including bleeding [3% (2, 4)], sternal infection [3% (2, 4)], and operative/30-day mortality [3% (2, 4)]. Conclusions HS required longer IMA harvest times which could be partially attributed to a higher skeletonization rate in this category. HS may cause less endothelial injury than EC; however, no significant differences in postoperative outcomes were seen between the groups.