Keywords:
Ischaemia / Infarction, Experimental investigations, Balloon occlusion, CT-Quantitative, CT, Cardiac, Animal (veterinary) studies
Authors:
G. J. Pelgrim1, T. duguay2, M. Stijnen3, A. Varga-Szemes4, S. Van Tuijl3, U. J. Schoepf4, M. Oudkerk1, R. Vliegenthart1; 1Groningen/NL, 2Charleston/US, 3Eindhoven/NL, 4Charleston, SC/US
Results
All hearts recovered in stable sinus rhythm.
In one case,
a mechanical failure in the pressure wire prevented analysis of the pressure drop across the stenosis.
Therefore,
this heart was excluded from analysis.
In five of the six hearts,
all dynamic perfusion scans acquisitions were analysable.
There were no significant artefacts that influenced image evaluation.
During the five successful experiments,
arterial blood flow in the system ranged from 800 to 1210 mL/min with a mean value of 1021 mL/min and heart rate ranged from 83 to 115 beats per minute (bpm) with a median heart rate of 111 bpm.
The mean arterial pressure ranged from 73 to 90 mmHg with a mean value of 81 mmHg.
80 (16 segments x 5 hearts) myocardial segments per stenosis grade (480 segments including all six stenosis grades) were analysed.
22 of 80 segments showed a perfusion defect,
based on the total occlusion scan,
resulting in a total of 132 ischaemic segments (6 stenosis grades x 22 segments) in the Cx territory.
At FFR ≤ 0.70,
a significant difference in CT-determined MBF was found between ischaemic and non-ischaemic segments (Mann-Whitney-U-test,
p<0.05) with a median MBF of 79 mL/100mL/min (IQR: 66-90) for non-ischaemic segments and 56 mL/100mL/min (IQR: 46-73) for ischaemic segments.
For MBV,
a significant difference between ischaemic and non-ischaemic segments was found at a FFR ≤ 0.80 (Mann-Whitney-U-test,
p<0.05) with median MBV values of 7.6 (IQR: 7.0-8.3) and 7.1 ml/100ml (IQR: 6.0-8.2) for the non-ischaemic and ischaemic myocardial segments,
respectively.