title: Use of 64-slice CT in symptomatic patients after coronary bypass surgery: evaluation of grafts and coronary arteries.
abstract: OBJECTIVE
  Although previous generations of multislice computed tomography (CT) have demonstrated accurate detection of obstructive bypass graft disease, progression of coronary disease is a more frequent cause for ischaemic symptoms late after bypass graft surgery. We explored the diagnostic performance of 64-slice CT in symptomatic patients after bypass surgery, for the assessment of both grafts and native coronary arteries.
  
  
  RESULTS
  The 64-slice CT angiography (Siemens Sensation 64, Germany) was performed in 52 symptomatic patients, 10 +/- 5 years after bypass surgery. Two independent, blinded observers assessed all grafts and coronary arteries for stenosis, using conventional quantitative angiography as a reference. A total of 109 grafts (182 graft segments), 123 distal coronary run-offs, and 116 non-bypassed coronary branches (288 segments) were analysed. Per-segment detection of graft disease yielded a sensitivity of 99% (71/72) and specificity of 96% (106/110). Sensitivity and specificity to detect run-off disease were 89% (8/9) and 93% (106/114), positive predictive value was 50% (8/16). In non-grafted coronary segments, CT detected significant stenosis with a sensitivity and specificity of 97% (62/64) and 86% (192/224). Overestimation occurred more frequently in calcified segments (P = 0.002).
  
  
  CONCLUSIONS
  The 64-slice CT allows angiographic evaluation of grafts and coronary arteries, although overestimation of coronary obstruction occurs, particularly in the presence of calcified disease.
authors.affiliation: Department of Cardiology, Thorax Centre, Erasmus Medical Center, PO Box 2040, Rotterdam 3000CA, The Netherlands.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Malagutti
authors.forename: Koen
authors.initials: K
authors.lastname: Nieman
authors.forename: Willem B
authors.initials: WB
authors.lastname: Meijboom
authors.forename: Carlos A G
authors.initials: CA
authors.lastname: van Mieghem
authors.forename: Francesca
authors.initials: F
authors.lastname: Pugliese
authors.forename: Filippo
authors.initials: F
authors.lastname: Cademartiri
authors.forename: Nico R
authors.initials: NR
authors.lastname: Mollet
authors.forename: Eric
authors.initials: E
authors.lastname: Boersma
authors.forename: Peter P
authors.initials: PP
authors.lastname: de Jaegere
authors.forename: Pim J
authors.initials: PJ
authors.lastname: de Feyter
mesh_terms: D000368:Aged; D017023:Coronary Angiography; D001026:Coronary Artery Bypass; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000473:pathology; D023921:Coronary Stenosis / Q000175:diagnosis; D003331:Coronary Vessels / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D015607:Stents; D013997:Time Factors; D014055:Tomography, Emission-Computed / Q000295:instrumentation*; D016896:Treatment Outcome