Changes in wall mechanics after endovascular stenting in the rabbit aorta: comparison of three stent designs.
OBJECTIVE
The aim of this study was to evaluate changes in the wall mechanics of small-diameter arteries after endovascular placement of three different stents.


METHODS
Five self-expandable stents (Wallstent), five balloon-expandable noncovered Palmaz stents, and three balloon-expandable covered stents (Jostent) were placed in the infrarenal aorta of 13 New Zealand white rabbits. Systolic blood pressure changes, blood-flow velocity, systolic diameter, and diameter changes were measured and used to calculate the diameter compliance, the distensibility coefficient, and the pulsatility index.


RESULTS
Compliance (10(-3) mm kPa(-1)) was 75.3 +/- 20.1 before stenting and reached 94.7 +/- 42.2 upstream, 38.8 +/- 14.2 at the stent level (p < 0.05), and 70.8 +/- 23.2 downstream from the stent. Distensibility (10(-3) kPa(-1)) was 24.3 +/- 6.3 before stenting and reached 27.8 +/- 10.3 upstream, 10.5 +/- 4.4 at the stent level (p < 0.001), and 21.9 +/- 8.6 downstream from the stent. Compliance and distensibility were significantly lower at the stent level than upstream and downstream (p < 0.05). Aortic diameter increased significantly at the stent level from 3.11 +/- 0.40 mm before to 3.76 +/- 0.42 mm after stenting. No significant difference was found among the three stent designs for all the studied data.


CONCLUSIONS
Regardless of the three tested stent designs, endovascular stenting produces a significant decrease in arterial wall compliance of the rabbit aorta.
Vernhet
H
H
Laboratory of Cardiovascular Physiology, Montpellier I University, Faculty of Medicine, Av. Kennedy, Nîmes F 30907, France.
Demaria
R
R
Juan
J M
JM
Oliva-Lauraire
M C
MC
Sénac
J P
JP
Dauzat
M
M
D000818:Animals; D001012:Aorta, Abdominal / Q000502:physiology*; D004867:Equipment Design; D006439:Hemodynamics / Q000502:physiology; D018056:Hemorheology; D008297:Male; D011817:Rabbits; D015607:Stents