Acute changes in aortic wall mechanical properties after stent placement in rabbits.
OBJECTIVE
To evaluate mechanical property changes after endovascular stent placement in small-diameter arteries.


METHODS
Self-expanding stents (Wallstent) were placed in the infrarenal aorta of five New Zealand White rabbits via a surgical right femoral approach. Blood pressure changes (deltaP) were monitored in the aorta. Blood flow velocity was measured with a 20-MHz, pulsed Doppler probe (n = 4) to calculate the pulsatility index. Aortic diameter (dA) and diameter changes (delta(d)) were measured with a 20-MHz probe in echo-tracking mode. Diameter compliance (Cd) and distensibility coefficient (DC) were calculated as Cd = 2(delta)d/(delta)P and DC = 2delta(d)/delta(P)/dA.


RESULTS
Aortic diameter increased from 3.360 +/- 0.4033 mm to 4.020 +/- 0.3033 mm after stent placement at the stent level only. Compliance decreased from 77.644 +/- 24.306 mm kPa(-1) to 31.150 +/-8.245 x 10(-3) mm kPa(-1) at the stent level, and was then significantly lower than upstream (98.500 +/- 53.196 mm kPa(-1)) and down-stream (59.047 +/- 13.833 mm kPa(-1)). There was no significant change in pulsatility index.


CONCLUSIONS
Endovascular stent placement produces a significant decrease in arterial wall compliance of the rabbit abdominal aorta.
Vernhet
H
H
Laboratory of Cardiovascular Physiology, Montpellier I University, Faculty of Medicine, Nimes, France.
Juan
J M
JM
Demaria
R
R
Oliva-Lauraire
M C
MC
Senac
J P
JP
Dauzat
M
M
D000210:Acute-Phase Reaction; D000818:Animals; D001012:Aorta, Abdominal / Q000503:physiopathology*; D001783:Blood Flow Velocity; D001794:Blood Pressure; D001807:Blood Vessel Prosthesis / Q000009:adverse effects*; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects; D008297:Male; D023421:Models, Animal; D011673:Pulsatile Flow; D011817:Rabbits; D015607:Stents / Q000009:adverse effects*