Effect of Electrocautery on Endothelial Integrity of the Internal Thoracic Artery: Ultrastructural Analysis with Transmission Electron Microscopy

Abstract

The internal thoracic artery (ITA) is typically harvested from the chest wall by means of conventional electrocautery. We investigated the effects of electrocautery on endothelial-cell and vessel-wall morphology at the ultrastructural level during ITA harvesting. Internal thoracic artery specimens from 20 patients who underwent elective coronary artery bypass grafting were investigated in 2 groups. The ITA grafts were sharply dissected with use of a scalpel and clips in the control group (n=10) and were harvested by means of electrocautery in the study group (n=10). Each sample was evaluated for intimal, elastic-tissue, muscular-layer, and adventitial changes. Free flow was measured intraoperatively. Light microscopic examinations were performed after hematoxylin-eosin and Masson's trichrome staining. Transmission electron microscopy was used to evaluate ultrastructural changes in the endothelial cells and vessel walls of each ITA. In the sharp-dissection group, the endothelial surfaces were lined with normal amounts of original endothelium, endothelial cells were distinctly attached to the basal lamina, cytoplasmic organelles were evident, and intercellular junctional complexes were intact. Conversely, in the electrocautery group, the morphologic integrity of endothelial cells was distorted, with some cell separations and splits, contracted cells, numerous large cytoplasmic vacuoles, and no visible cytoplasmic organelles. The subendothelial layer exhibited disintegration. Free ITA flow was higher in the sharp-dissection group (P=0.04). The integrity of endothelial cells can be better preserved when the ITA is mobilized by means of sharp dissection, rather than solely by electrocautery; we recommend a combined approach.

Clipless internal mammary artery harvesting for minimally invasive coronary artery bypass grafting using the shear-tip harmonic scalpel

“…During skeletonization, Metzenbaum scissors and electrocautery are commonly used to separate the IMA from the surrounding tissue of the sternum prior to clipping the branch vessels ( 23 ). Electrocautery can cause endothelial damage or graft wall thrombosis ( 24 , 25 ). Electrocautery devices deliver electrical energy resulting in heat ranging from 100–1,200 °C in the tissue, which can result in thermal damage to surrounding tissues within 2 cm ( 26 , 27 ).…”

Ultrastructural Investigations of Arterial Bypass Conduits after the Use of Different Harvesting Techniques Using an Electron Microscope

“…Frequently, the harmonic scalpel as a new medical device is used for cutting and coagulating with high-frequency ultrasonic vibrations in laparoscopic surgery. Unlike electrocautery, the harmonic scalpel can be used closer than 1 mm from vascular tissue without any hemorrhagic complication during tissue dissections in a number of surgical procedures [Takao 2000;Ohtsuka 1998;Onan 2014].…”

“…Pathologic changes of the arterial conduits, including endothelial disintegration, corruption, or dissection and spasm related to thermal injury, have been reported in a number of investigations [Ohtsuka 1998;Onan 2014]. Endothelial complications as a result of the use of electrocautery have been reported by Onan et al [2014]. They suggested a sharp dissection method during ITA mobilization to ensure endothelial integrity of the ITA conduit rather than electrocautery [Onan 2014].…”

“…Endothelial complications as a result of the use of electrocautery have been reported by Onan et al [2014]. They suggested a sharp dissection method during ITA mobilization to ensure endothelial integrity of the ITA conduit rather than electrocautery [Onan 2014]. Therefore, different techniques and devices have been proposed to decrease endothelial injury, harvesting time, and frequency of spasm.…”