Comparison of thermal damage of the internal thoracic artery using ultra high radiofrequency and monopolar diathermy

BackgroundThe internal thoracic artery (ITA) has been accepted worldwide as a first choice conduit for myocardial revascularisation. It still remains questionable what is the best method for ITA harvesting in a skeletonized fashion according to structural integrity of artery, as a risk factor of early and late graft failure. The purpose of this study was to determine the impact of the ultra-high radiofrequency energy used for ITA harvesting on arterial structural integrity, in particular on the endothelial layer.MethodsSeventy-four ITA specimens were divided into two groups depending on device used for harvesting (radiofrequency-knife (RF) or electrocauter (EC)). Thermal damage on arterial structural integrity was measured using light microscope, morphometric imaging analysis and immunohistochemical methods.ResultsThermal damage of endothelium was 2.8 times higher in EC than in RF group (p = 0.041) and 5 times higher in patients older than 66 years of age (p = 0.002). Extent of endothelial damage (graded from 0 to 3) was significantly higher in EC group (p = 0.03). Also, in EC group, in patients older than 66 years of age higher proportion of extent of endothelial damage was found (p = 0.027).ConclusionsThe endothelial damage was more often in EC than in RF group as in the patients older than 66 years of age. Demonstrated results suggest that the radiosurgery in comparison to conventional electrocautery is safe and effective method, and significantly reduces thermal damage to endothelial layer of artery.