Pedicled or skeletonized bilateral internal mammary artery harvesting - a meta- analysis and trial sequential analysis

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.

Multi-Omics Profiling of Human Endothelial Cells from the Coronary Artery and Internal Thoracic Artery Reveals Molecular but Not Functional Heterogeneity

Major adverse cardiovascular events occurring upon coronary artery bypass graft surgery are typically accompanied by endothelial dysfunction. Total arterial revascularisation, which employs both left and right internal thoracic arteries instead of the saphenous vein to create a bypass, is associated with better mid- and long-term outcomes. We suggested that molecular profiles of human coronary artery endothelial cells (HCAECs) and human internal mammary artery endothelial cells (HITAECs) are coherent in terms of transcriptomic and proteomic signatures, which were then investigated by RNA sequencing and ultra-high performance liquid chromatography-mass spectrometry, respectively. Both HCAECs and HITAECs overexpressed molecules responsible for the synthesis of extracellular matrix (ECM) components, basement membrane assembly, cell-ECM adhesion, organisation of intercellular junctions, and secretion of extracellular vesicles. HCAECs were characterised by higher enrichment with molecular signatures of basement membrane construction, collagen biosynthesis and folding, and formation of intercellular junctions, whilst HITAECs were notable for augmented pro-inflammatory signaling, intensive synthesis of proteins and nitrogen compounds, and enhanced ribosome biogenesis. Despite HCAECs and HITAECs showing a certain degree of molecular heterogeneity, no specific markers at the protein level have been identified. Coherence of differentially expressed molecular categories in HCAECs and HITAECs suggests synergistic interactions between these ECs in a bypass surgery scenario.

Comparison of Long-term Clinical Outcomes of Skeletonized vs Pedicled Internal Thoracic Artery Harvesting Techniques in the Arterial Revascularization Trial

Importance

Recent evidence has suggested that skeletonization of the internal thoracic artery (ITA) is associated with worse clinical outcomes in patients undergoing coronary artery bypass surgery (CABG).

Objective

To compare the long-term clinical outcomes of skeletonized and pedicled ITA for CABG.

Design, Setting, and Participants

The Arterial Revascularization Trial (ART) was a 2-group, multicenter trial comparing the use of a bilateral ITA vs a single ITA for CABG at 10 years. Patients in the ART trial were stratified by ITA harvesting technique: skeletonized vs pedicled. Data were collected from June 2004 to December 2017, and data were analyzed from June to July 2021.

Interventions

In this analysis, the 10-year clinical outcomes were compared between patients who received skeletonized vs pedicled ITAs.

Main Outcomes and Measures

The primary outcome was all-cause mortality. The secondary outcomes were a composite of major adverse cardiac events (MACE) including all-cause mortality, myocardial infarction, and repeated revascularization and a composite including MACE and sternal wound complication (SWC). Cox regression and propensity score matching were used.

Results

Of 2161 included patients, 295 (13.7%) were female, and the median (interquartile range) age was 65.0 (58.0-70.0) years. At 10 years, the risk of all-cause mortality was not significantly different between the pedicled and skeletonized groups (hazard ratio [HR], 1.12; 95% CI, 0.92-1.36; P = .27). However, the long-term risks of the secondary outcomes were significantly higher in the skeletonized group compared with the pedicled group (MACE: HR, 1.25; 95% CI, 1.06-1.47; P = .01; MACE and SWC: HR, 1.22; 95% CI, 1.05-1.43; P = .01). The difference was not seen when considering only patients operated on by surgeons who enrolled 51 patients or more in the trial (MACE: HR, 1.07; 95% CI, 0.82-1.39; P = .62; MACE and SWC: HR, 1.04; 95% CI, 0.80-1.34; P = .78).

Conclusions and Relevance

While the long-term survival of patients was not different between groups, the rate of adverse cardiovascular events was consistently higher in the skeletonized group and the difference was associated with surgeon-related factors. Further evidence on the outcome of skeletonized ITA is needed.