title: Preliminary experience with a novel intraoperative fluorescence imaging technique to evaluate the patency of bypass grafts in total arterial revascularization.
abstract: BACKGROUND
  Early graft failure is a common cause of cardiac morbidity and mortality after coronary artery bypass grafting (CABG), and there is particular concern about graft patency in off-pump CABG. We describe our preliminary experience with a novel imaging technique (the SPY system), based on fluorescence of Indocyanine Green when exposed to near infrared light, for the intraoperative assessment of coronary graft patency.
  
  
  METHODS
  Graft patency was assessed in patients undergoing off-pump and on-pump total arterial revascularization. The imaging technique requires injection of a 1-mL bolus of Indocyanine Green into the central venous line, followed by imaging with the SPY system.
  
  
  RESULTS
  We assessed intraoperative graft patency in 213 conduits in 84 patients (mean, 2.54 grafts per patient), of which, 65 (77%) were done off-pump. It took approximately 3 minutes to image each graft. Skeletonized conduits provided better visualization than pedicled ones. Fluorescence, confirming graft patency, was observed in all but four (1.9%) conduits in 4 (5%) patients. In these latter cases, graft revision was necessitated.
  
  
  CONCLUSIONS
  Fluorescence imaging of coronary grafts using the SPY is a uniquely simple, safe, noninvasive, and reproducible technique for intraoperative confirmation of graft patency. In 4 patients, it necessitated revision of the initial intraoperative procedure. Quantification of graft flow would enhance the value of the system.
authors.affiliation: Department of Cardiothoracic Surgery, John Radcliffe Hospital, Oxford, United Kingdom. david.taggart@orh.nhs.uk
authors.forename: David P
authors.initials: DP
authors.lastname: Taggart
authors.forename: Bikram
authors.initials: B
authors.lastname: Choudhary
authors.forename: Kyriakos
authors.initials: K
authors.lastname: Anastasiadis
authors.forename: Yasir
authors.initials: Y
authors.lastname: Abu-Omar
authors.forename: Lognathen
authors.initials: L
authors.lastname: Balacumaraswami
authors.forename: David W
authors.initials: DW
authors.lastname: Pigott
mesh_terms: D000368:Aged; D001158:Arteries / Q000637:transplantation; D002315:Cardiopulmonary Bypass; D001026:Coronary Artery Bypass; D003327:Coronary Disease / Q000601:surgery*; D023903:Coronary Restenosis / Q000175:diagnosis*; D005451:Fluorescein Angiography; D006083:Graft Occlusion, Vascular / Q000175:diagnosis*; D006801:Humans; D007208:Indocyanine Green; D007431:Intraoperative Complications / Q000175:diagnosis; D008297:Male; D019060:Minimally Invasive Surgical Procedures; D012680:Sensitivity and Specificity; D014741:Video Recording
chemical_list: D007208:Indocyanine Green