title: Harmonic scalpel versus electrocautery for harvest of radial artery conduits: reduced risk of spasm and intimal injury on optical coherence tomography.
abstract: OBJECTIVE
  Vasospasm is the primary obstacle to widespread adoption of the radial artery as a conduit in coronary artery bypass grafting. We used optical coherence tomography, a catheter-based intravascular imaging modality, to measure the degree of radial artery spasm induced by means of harvest with electrocautery or a harmonic scalpel in patients undergoing coronary artery bypass grafting.
  
  
  METHODS
  Radial arteries were harvested from 44 consecutive patients with a harmonic scalpel (n = 15) or electrocautery (n = 29). Vessels were imaged before harvesting and after removal from the arm, with saphenous vein tracts serving as internal controls. Optical coherence tomographic findings for the degree of harvesting-induced injury were validated against histologic measures.
  
  
  RESULTS
  Optical coherence tomographic measures of endovascular dimensions and injury correlated strongly with histologic findings. Mean luminal volume, a measure of vasospasm, decreased significantly less after harvesting with a harmonic scalpel (9% +/- 7%) than with electrocautery (35% +/- 6%, P = .015). Completely intact intima was present in 11 (73%) of 15 radial arteries harvested with a harmonic scalpel (73%) compared with 9 of 29 arteries harvested by means of electrocautery (31%, P = .011). Intraoperative flow measurements and patency rates at 5 days postoperatively were not significantly different among groups.
  
  
  CONCLUSIONS
  Optical coherence tomography provides a level of speed and accuracy for quantifying endothelial injury and vasospasm that has not been described for any other modality, suggesting potential as an intraoperative quality assurance tool. Our optical coherence tomographic findings suggest that the harmonic scalpel induces less spasm and intimal injury compared with electrocautery.
authors.affiliation: Division of Cardiac Surgery, University of Maryland School of Medicine, Baltimore, MD, USA.
authors.forename: Philip S
authors.initials: PS
authors.lastname: Brazio
authors.forename: Patrick C
authors.initials: PC
authors.lastname: Laird
authors.forename: Chenyang
authors.initials: C
authors.lastname: Xu
authors.forename: Junyan
authors.initials: J
authors.lastname: Gu
authors.forename: Nicholas S
authors.initials: NS
authors.lastname: Burris
authors.forename: Emile N
authors.initials: EN
authors.lastname: Brown
authors.forename: Zachary N
authors.initials: ZN
authors.lastname: Kon
authors.forename: Robert S
authors.initials: RS
authors.lastname: Poston
mesh_terms: D000368:Aged; D001026:Coronary Artery Bypass / Q000379:methods*; D004564:Electrocoagulation / Q000379:methods; D005260:Female; D006801:Humans; D007431:Intraoperative Complications / Q000517:prevention & control; D008297:Male; D017534:Radial Artery / Q000033:anatomy & histology / Q000637:transplantation*; D013035:Spasm / Q000517:prevention & control*; D020858:Tissue and Organ Harvesting / Q000379:methods*; D041623:Tomography, Optical Coherence; D017539:Tunica Intima / Q000033:anatomy & histology; D014654:Vascular Patency