title: Fatigue and in vivo validation of a peritoneum-lined self-expanding nitinol stent-graft.
abstract: OBJECTIVE
  To assess the fatigue and in vivo performance of a new stent-graft incorporating bovine peritoneum lining that is designed for application in peripheral vascular occlusive disease.
  
  
  METHODS
  Bovine peritoneum-lined stent-grafts were subjected to accelerated in vitro pulsatile fatigue and axial/torsional fatigue testing designed to simulate 10 years of physiological strain on the devices. At specified times the devices were evaluated for stent fracture, suture failure, or tissue tearing. Seven dogs underwent bilateral common iliac artery (CIA) balloon angioplasty injury with unilateral placement of the peritoneum-lined stent-graft. Angiography and intravascular ultrasound were performed prior to treatment, after treatment, and prior to sacrifice at 30 days. Vessels were perfusion fixed and histologically evaluated at 5 regions: above stent, proximal stent, mid stent, distal stent, and below stent.
  
  
  RESULTS
  No evidence of stent, suture, or tissue failure was present during or after pulsatile and axial/torsional fatigue testing. At 30±0.3 days after implantation, all vessels were patent. The average lumen area at explantation across stented vessels was 25.45 mm(2). Lumen areas tended to be reduced above (23.57 mm(2)) and below (24.17 mm(2)) the stent. Lumen areas were consistent across stented regions at explantation (proximal stent 27.80 mm(2), mid stent 25.88 mm(2), and distal stent 25.81 mm(2)). The mean neointimal area in peritoneum-lined stents was 2.02±1.52 mm(2), with a neointima:media ratio of 1.03±0.50. These values were significantly lower in the above and below stent areas than in the stented regions, but there was no difference in either measure within the proximal, mid, or distal stent.
  
  
  CONCLUSIONS
  The custom-designed peritoneum-lined stent-graft is promising for clinical peripheral applications due to its ability to resist relevant long-term physiological stresses and outstanding short-term patency rates in canine implantations.
authors.affiliation: 1 PeriTec Biosciences, LTD., Cleveland, Ohio, USA.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Bastijanic
authors.forename: Jordan
authors.initials: J
authors.lastname: Etscheidt
authors.forename: Mallika
authors.initials: M
authors.lastname: Sattiraju
authors.forename: Craig
authors.initials: C
authors.lastname: Bonsignore
authors.forename: George
authors.initials: G
authors.lastname: Kopchok
authors.forename: Rodney
authors.initials: R
authors.lastname: White
authors.forename: Timur P
authors.initials: TP
authors.lastname: Sarac
mesh_terms: D000497:Alloys; D000818:Animals; D001705:Bioprosthesis; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000295:instrumentation*; D002417:Cattle; D004195:Disease Models, Animal; D004285:Dogs; D057510:Endovascular Procedures / Q000295:instrumentation*; D019544:Equipment Failure Analysis; D005260:Female; D006439:Hemodynamics; D007083:Iliac Artery / Q000293:injuries / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D008422:Materials Testing; D010537:Peritoneum / Q000637:transplantation*; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012039:Regional Blood Flow; D015607:Stents; D013314:Stress, Mechanical; D013997:Time Factors; D054159:Torsion, Mechanical; D057772:Vascular System Injuries / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*
chemical_list: D000497:Alloys; C013616:nitinol
keywords: axial torsional fatigue; canine model; in vitro testing; in vivo experiment; neointimal hyperplasia; nitinol stent; peritoneum; pulsatile fatigue; self-expanding stent; stent-graft