title: Coronary bypass graft patency cannot be determined by multidetector spiral computed tomography.
abstract: OBJECTIVE
  Angiography by selective catheterization is the reference standard for coronary bypass graft patency assessment but carries a risk of serious complications. We have investigated whether 16-slice multidetector spiral computed tomography (MDCT) can substitute for selective angiography.
  
  
  METHODS
  Two to three years after coronary artery bypass grafting, 45 patients with a total of 156 bypasses (100 single and 28 sequential grafts) were examined with both MDCT and conventional selective angiography on the same day. The bypasses were classified as patent, stenotic or occluded.
  
  
  RESULTS
  The likelihood ratio for MDCT-detected occlusion was 40, reflecting a fairly high combined sensitivity and specificity. However, 24% of the distal anastomoses could not be evaluated by MDCT, mainly because of respiratory movements, artifacts due to metal clips, and small vessel dimensions. Moreover, seven out of 117 bypasses (6%) deemed evaluable by MDCT were wrongly classified by this method.
  
  
  CONCLUSIONS
  At present, 16-slice MDCT cannot replace selective angiography for assessment of coronary bypass graft patency since 24% of bypasses could not be evaluated by this method, and an error rate of 6% is unacceptable.
authors.affiliation: Department of Cardiothoracic and Vascular Surgery, University Hospital North Norway, Tromsø, Norway. kristian.bartnes@unn.no
authors.forename: Kristian
authors.initials: K
authors.lastname: Bartnes
authors.forename: Trude
authors.initials: T
authors.lastname: Sildnes
authors.forename: Amjid
authors.initials: A
authors.lastname: Iqbal
authors.forename: Oystein
authors.initials: O
authors.lastname: Dahl-Eriksen
authors.forename: Thor
authors.initials: T
authors.lastname: Trovik
authors.forename: Terje Kristian
authors.initials: TK
authors.lastname: Steigen
authors.forename: Rica
authors.initials: R
authors.lastname: Mortensen
authors.forename: Jan Torbjørn
authors.initials: JT
authors.lastname: Mannsverk
authors.forename: Dag Glen
authors.initials: DG
authors.lastname: Sørlie
authors.forename: Truls
authors.initials: T
authors.lastname: Myrmel
mesh_terms: D000328:Adult; D000368:Aged; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods / Q000592:standards*; D001026:Coronary Artery Bypass; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway; D011237:Predictive Value of Tests; D012119:Respiration; D013673:Technology Assessment, Biomedical; D036542:Tomography, Spiral Computed / Q000379:methods / Q000592:standards*; D014654:Vascular Patency
chemical_list: D003287:Contrast Media