title: Surgeon judgment and utility of transit time flow probes in coronary artery bypass grafting surgery.
abstract: OBJECTIVE
  Transit time flow (TTF) probes may be useful for predicting long-term graft patency and assessing grafts intraoperatively in patients undergoing coronary artery bypass grafting (CABG); however, studies of TTF probe use are limited.
  
  
  OBJECTIVE
  To examine 1-year graft patency and intraoperative revision rates in patients undergoing CABG based on intraoperative TTF assessment.
  
  
  METHODS
  Retrospective analysis of a multicenter randomized clinical trial conducted at 18 Veterans Affairs hospitals using the Randomized On/Off Bypass (ROOBY) Trial data set. Of the original 2203 patients undergoing CABG surgery with or without cardiopulmonary bypass from February 1, 2002, through May 31, 2008, we studied a subset of 1607 who underwent TTF probe analysis of 1 or more grafts during surgery.
  
  
  METHODS
  Use of TTF probes to assess graft flow and pulsatility index (PI) values. The decision to revise a graft was based on the judgment of the attending surgeon.
  
  
  METHODS
  Rates of 1-year FitzGibbon grade A patency and intraoperative revision were compared based on TTF measurements (<20 [low flow] vs ≥20 mL/min [normal flow]) and PI values (<3, 3-5, and >5).
  
  
  RESULTS
  We measured TTF and/or PI in 2738 grafts, and 1-year patency was determined in 1710 (62.5%) of these grafts. FitzGibbon grade A patency occurred significantly less often in grafts with a TTF with low flow (259 of 363 [71.3%]) than in those with normal flow (1174 of 1347 [87.2%]; P < .01). FitzGibbon grade A patency was also inversely correlated with increasing PI values, as found in 936 of 1093 grafts (85.6%) with a PI less than 3, 136 of 182 grafts (74.7%) with a PI of 3 to 5, and 91 of 134 grafts (67.9%) with a PI greater than 5 (P ≤ .01). Intraoperative graft revision was more frequent in grafts with low flow (44 of 568 [7.7%]) than in those with normal flow (8 of 2170 [0.4%]; P < .01). Graft revision was also more frequent as PI increased (12 of 1827 [0.7%] with a PI <3, 9 of 307 [2.9%] with a PI 3-5, and 9 of 155 [5.8%] with a PI >5; P < .01).
  
  
  CONCLUSIONS
  Intraoperative TTF probe data may be helpful in predicting long-term patency and in the decision of whether to revise a questionable graft for patients undergoing CABG surgery.
authors.affiliation: Surgery Service, Veterans Affairs (VA) Boston Healthcare System, West Roxbury, Massachusetts.
authors.forename: Jacquelyn
authors.initials: J
authors.lastname: Quin
authors.affiliation: Surgery Service, Charles George VA Medical Center, Asheville, North Carolina.
authors.forename: John
authors.initials: J
authors.lastname: Lucke
authors.affiliation: Medicine Service, Department of VA Eastern Colorado Health Care System, Denver4Department of Medicine, University of Colorado School of Medicine-Anschutz Medical Campus, Aurora.
authors.forename: Brack
authors.initials: B
authors.lastname: Hattler
authors.affiliation: Surgery Service, Northport VA Medical Center and Stony Brook University, Stony Brook, New York.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Gupta
authors.affiliation: Surgery Service, Department of VA Eastern Colorado Health Care System, Denver.
authors.forename: Janet
authors.initials: J
authors.lastname: Baltz
authors.affiliation: Surgery Service, Northport VA Medical Center and Stony Brook University, Stony Brook, New York6currently with Division of Cardiothoracic Surgery, Department of Surgery, Duke University Hospital, Durham, North Carolina.
authors.forename: Muath
authors.initials: M
authors.lastname: Bishawi
authors.affiliation: Surgery Service, Milwaukee VA Medical Center, Milwaukee, Wisconsin.
authors.forename: G Hossein
authors.initials: GH
authors.lastname: Almassi
authors.affiliation: Surgery Service, Department of VA Eastern Colorado Health Care System, Denver9Department of Surgery, University of Colorado School of Medicine-Anschutz Medical Campus, Aurora.
authors.forename: Frederick L
authors.initials: FL
authors.lastname: Grover
authors.affiliation: Cooperative Studies Program Coordinating Center and VA Medical Center, Perry Point, Maryland.
authors.forename: Joseph
authors.initials: J
authors.lastname: Collins
authors.affiliation: Surgery Service, Northport VA Medical Center and Stony Brook University, Stony Brook, New York7Surgery Service, Department of VA Eastern Colorado Health Care System, Denver.
authors.forename: A Laurie
authors.initials: AL
authors.lastname: Shroyer
mesh_terms: D001026:Coronary Artery Bypass / Q000379:methods*; D006787:Hospitals, Veterans / Q000706:statistics & numerical data; D006801:Humans; D007600:Judgment; D016343:Monitoring, Intraoperative / Q000379:methods*; D015337:Multicenter Studies as Topic; D009204:Myocardial Revascularization / Q000379:methods; D011237:Predictive Value of Tests; D016032:Randomized Controlled Trials as Topic; D012086:Reoperation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012212:Rheology / Q000379:methods*; D012501:Saphenous Vein / Q000637:transplantation; D016896:Treatment Outcome; D014654:Vascular Patency