title: Non-invasive assessment of functionally relevant coronary artery stenoses with quantitative CT perfusion: preliminary clinical experiences.
abstract: OBJECTIVE
  We developed a quantitative Dynamic Contrast-Enhanced CT (DCE-CT) technique for measuring Myocardial Perfusion Reserve (MPR) and Volume Reserve (MVR) and studied their relationship with coronary stenosis.
  
  
  METHODS
  Twenty-six patients with Coronary Artery Disease (CAD) were recruited. Degree of stenosis in each coronary artery was classified from catheter-based angiograms as Non-Stenosed (NS, angiographically normal or mildly irregular), Moderately Stenosed (MS, 50-80% reduction in luminal diameter), Severely Stenosed (SS, >80%) and SS with Collaterals (SSC). DCE-CT at rest and after dipyridamole infusion was performed using 64-slice CT. Mid-diastolic heart images were corrected for beam hardening and analyzed using proprietary software to calculate Myocardial Blood Flow (MBF, in mL∙min(-1)∙100 g(-1)) and Blood Volume (MBV, in mL∙100 g(-1)) parametric maps. MPR and MVR in each coronary territory were calculated by dividing MBF and MBV after pharmacological stress by their respective baseline values.
  
  
  RESULTS
  MPR and MVR in MS and SS territories were significantly lower than those of NS territories (p < 0.05 for all). Logistic regression analysis identified MPR∙MVR as the best predictor of ≥50% coronary lesion than MPR or MVR alone.
  
  
  CONCLUSIONS
  DCE-CT imaging with quantitative CT perfusion analysis could be useful for detecting coronary stenoses that are functionally significant.
authors.affiliation: Imaging Program, Lawson Health Research Institute, London, Ontario, Canada. aso@imaging.robarts.ca
authors.forename: Aaron
authors.initials: A
authors.lastname: So
authors.forename: Gerald
authors.initials: G
authors.lastname: Wisenberg
authors.forename: Ali
authors.initials: A
authors.lastname: Islam
authors.forename: Justin
authors.initials: J
authors.lastname: Amann
authors.forename: Walter
authors.initials: W
authors.lastname: Romano
authors.forename: James
authors.initials: J
authors.lastname: Brown
authors.forename: Dennis
authors.initials: D
authors.lastname: Humen
authors.forename: George
authors.initials: G
authors.lastname: Jablonsky
authors.forename: Jian-Ying
authors.initials: JY
authors.lastname: Li
authors.forename: Jiang
authors.initials: J
authors.lastname: Hsieh
authors.forename: Ting-Yim
authors.initials: TY
authors.lastname: Lee
mesh_terms: D000704:Analysis of Variance; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D004176:Dipyridamole; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D007091:Image Processing, Computer-Assisted; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology; D012372:ROC Curve; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods; D014665:Vasodilator Agents
chemical_list: D003287:Contrast Media; D014665:Vasodilator Agents; D004176:Dipyridamole