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

Background: The 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. Methods: Seventy-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. Results: Thermal damage of endothelium was 2.8 times higher in EC than in RF group (p ¼ 0.041) and 5 times higher in patients older than 66 years of age (p ¼ 0.002). Extent of endothelial damage (graded from 0 to 3) was significantly higher in EC group (p ¼ 0.03). Also, in EC group, in patients older than 66 years of age higher proportion of extent of endothelial damage was found (p ¼ 0.027). Conclusions: The 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