title: Computerized tomography may underestimate the patency of internal thoracic artery composite grafts.
abstract: BACKGROUND
  Multidetector-row computerized tomography (MDCT) has been regarded as useful for noninvasive assessment of the bypass grafts after coronary artery bypass grafting (CABG), but there have been few reports validating its accuracy in assessment of composite arterial graft patency.
  
  
  METHODS
  In 108 patients who underwent CABG with a Y-composite graft made of bilateral internal thoracic arteries (ITAs), early postoperative (mean interval, 4.9 months) MDCT findings were compared with the findings of subsequent conventional coronary angiography (19 patients, mean 4.7 months after initial MDCT) or later MDCT (89 patients, mean 31.0 months after surgery). A total of 248 grafts with 409 distal anastomoses (mean 3.8/patient) were assessed.
  
  
  RESULTS
  In the early MDCT, the left ITA was patent in 94.4%. The right ITA with multiple sequential anastomoses was completely patent in 73.8% and partially patent in 21.4%. Discrepancy of findings between early computed tomography (CT) and later imaging studies was found in 18 patients (16.7%). Fourteen (42.4%, 4 left and 10 right ITAs) among the 33 initially nonvisualized grafts showed improved patency in later MDCT or conventional angiogram. The positive predictive value of the early MDCT for ITA composite graft occlusion was calculated at 57.6% or lower, whereas the negative predictive value was 97.8% or higher.
  
  
  CONCLUSIONS
  For a composite graft made of bilateral ITAs, especially for those with multiple sequential anastomoses, MDCT may reflect only the functional patency and underestimate the actual anatomic patency.
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Cheong
authors.initials: C
authors.lastname: Lim
authors.forename: Kay-Hyun
authors.initials: KH
authors.lastname: Park
authors.forename: Tae-Hun
authors.initials: TH
authors.lastname: Kim
authors.forename: Yochun
authors.initials: Y
authors.lastname: Jung
authors.forename: Il
authors.initials: I
authors.lastname: Park
authors.forename: Sang Il
authors.initials: SI
authors.lastname: Choi
authors.forename: Eun Ju
authors.initials: EJ
authors.lastname: Chun
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017023:Coronary Angiography / Q000706:statistics & numerical data; D001026:Coronary Artery Bypass / Q000295:instrumentation / Q000706:statistics & numerical data; D003324:Coronary Artery Disease / Q000453:epidemiology* / Q000601:surgery*; D005188:False Negative Reactions; D005260:Female; D005858:Germany / Q000453:epidemiology; D006084:Graft Rejection / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008323:Mammary Arteries / Q000000981:diagnostic imaging* / Q000637:transplantation*; D008875:Middle Aged; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data*; D016896:Treatment Outcome