title: In-vivo measurements of coronary blood flow using 16-slice multidetector spiral computed tomography (MDCT) in a porcine model.
abstract: OBJECTIVE
  To determine whether CTCA supplemented with CT flow measurements can be used to demonstrate and semiquantitatively evaluate poststenotic coronary blood flow in a porcine model.
  
  
  METHODS
  In 10 thoracotomized pigs, transit time flow meter probes were attached to the aorta and left anterior descending artery (LAD) for real-time blood flow volumetry. A vascular silicone occluder was deployed around the LAD proximal to the probe to create medium-grade (MGS) and high-grade stenoses (HGS). The blood flow was measured by CT without vessel occlusion and distal to the stenoses. Time-density curves were generated from CT data. The curves were evaluated by calculating and cross-plotting the variables "slope of the density increase", "peak density" and "slope of the post-peak density decrease" from the LAD and aortic CT data.
  
  
  RESULTS
  The flow in the LAD dropped to 41 % +/- 9 % (mean +/- SD) for MGS and 12 % +/- 6 % for HGS of the baseline. Coronary time-density curves plateaued proportional to luminal narrowing. Unimpaired flow could be differentiated statistically significant from poststenotic flow adjacent to MGS and HGS (p < 0.000 and p < 0.002, respectively). Flow adjacent to MGS and HGS was successfully differentiated for "slope of the density increase" and "slope of the post-peak density decrease" (p < 0.003 and p < 0.030, respectively).
  
  
  CONCLUSIONS
  CT measurements allow semiquantitative evaluation of poststenotic coronary blood flow.
authors.affiliation: Institut und Poliklinik für Radiologische Diagnostik, Klinikum der Universität zu Köln, Köln, Germany. barbara.krug@uk-koeln.de
authors.forename: K B
authors.initials: KB
authors.lastname: Krug
authors.forename: H
authors.initials: H
authors.lastname: Bovenschulte
authors.forename: H J
authors.initials: HJ
authors.lastname: Geissler
authors.forename: M
authors.initials: M
authors.lastname: Flesch
authors.forename: T
authors.initials: T
authors.lastname: Schneider
authors.forename: D
authors.initials: D
authors.lastname: Brackrogge
authors.forename: H
authors.initials: H
authors.lastname: Reiter
authors.forename: I
authors.initials: I
authors.lastname: Heppelmann
authors.forename: H
authors.initials: H
authors.lastname: Christ
authors.forename: J H
authors.initials: JH
authors.lastname: Fischer
authors.forename: K-J
authors.initials: KJ
authors.lastname: Lackner
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology; D001810:Blood Volume / Q000502:physiology; D003287:Contrast Media; D017023:Coronary Angiography / Q000295:instrumentation / Q000379:methods*; D003326:Coronary Circulation / Q000502:physiology*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology; D004867:Equipment Design; D045268:Flowmeters; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007479:Iopamidol / Q000031:analogs & derivatives; D008955:Models, Cardiovascular; D012680:Sensitivity and Specificity; D013552:Swine; D036542:Tomography, Spiral Computed / Q000295:instrumentation / Q000379:methods*
chemical_list: D003287:Contrast Media; C057937:iomeprol; D007479:Iopamidol