In-vivo measurements of coronary blood flow using 16-slice multidetector spiral computed tomography (MDCT) in a porcine model.
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.
Krug
K B
KB
Institut und Poliklinik für Radiologische Diagnostik, Klinikum der Universität zu Köln, Köln, Germany. barbara.krug@uk-koeln.de
Bovenschulte
H
H
Geissler
H J
HJ
Flesch
M
M
Schneider
T
T
Brackrogge
D
D
Reiter
H
H
Heppelmann
I
I
Christ
H
H
Fischer
J H
JH
Lackner
K-J
KJ
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*
D003287:Contrast Media; C057937:iomeprol; D007479:Iopamidol