title: Histopathologic evaluation of a novel-design nitinol stent: the Biflex stent.
abstract: BACKGROUND
  Optimalization and improvement in stent material, stent design and deployment may alleviate the problem of restenosis after stenting. The Biflex stent is a novel-design stent made of nitinol; the vascular response after deployment in rabbit iliac arteries was evaluated.
  
  
  RESULTS
  Normocholesterolemic New Zealand white rabbits (n = 8) were used. Iliac arteries were randomized to receive either a stainless steel control stent or a nitinol stent and rabbits were euthanized at 30 days after implantation. All animals survived and there were no adverse events. Vessels were harvested and prepared for histopathologic analysis and histomorphometry. Stents were well opposed to the vessel wall and thrombi were absent. The lumen area and the area within the internal elastic lamina were significantly larger in the nitinol stent group as opposed to the control group (3.8 +/- 0.1 vs 3.3 +/- 0.1 mm, p = 0.009 and 4.6 +/- 0.1 vs 4.1 +/- 0.2 mm, p = 0.03, respectively). There were no differences in injury score, neointimal area, medial area, area within the external elastic lamina and amount of inflammatory cells. Staining for alpha-smooth muscle cell actin and endothelium did not show any differences between the two groups as assessed semiquantitatively.
  
  
  CONCLUSIONS
  This nitinol stent with a novel design demonstrated acceptable biocompatibility in iliac arteries of normocholesterolemic rabbits with minimal foreign-body reaction and minimal neointimal formation.
authors.affiliation: Cardiovascular Translational Research Institute, Antwerp, Belgium. stefan.verheye@pandora.be
authors.forename: Stefan
authors.initials: S
authors.lastname: Verheye
authors.forename: Guido
authors.initials: G
authors.lastname: De Meyer
authors.forename: Koen
authors.initials: K
authors.lastname: Salu
authors.forename: Michiel
authors.initials: M
authors.lastname: Knaapen
authors.forename: Mark
authors.initials: M
authors.lastname: Kockx
mesh_terms: D000497:Alloys; D000818:Animals; D001157:Arterial Occlusive Diseases / Q000517:prevention & control / Q000628:therapy*; D001672:Biocompatible Materials; D004867:Equipment Design; D007083:Iliac Artery / Q000473:pathology*; D008297:Male; D011817:Rabbits; D013193:Stainless Steel; D015607:Stents
chemical_list: D000497:Alloys; D001672:Biocompatible Materials; D013193:Stainless Steel; C013616:nitinol