title: Novel stent system for accurate placement in aorto-ostial renal artery disease: preclinical study in porcine renal artery model.
abstract: BACKGROUND
  Treatment of aorto-ostial renal artery stenosis has been associated with a lower procedural success and higher complication and restenosis rate, as compared to nonostial lesions. The design and delivery of currently available stent systems in ostial lesions can result in inaccurate stent positioning and placement leading to stent protrusion into the parent vessel lumen or geographic miss. A novel stent system (SquareOne Inc., Campbell, CA, USA) has been designed specifically for aorto-ostial lesions in the renal artery. This stent system aims to provide both tactile and visual confirmation of the ostium at the aorta, allow for improved accuracy during stent positioning and placement, provide complete scaffolding of the lesion at the aortic junction to the native vessel, and enable future vessel reaccess.
  
  
  METHODS
  Stents (n=12) were implanted in both renal arteries of six swine. For histology, two animals were euthanized immediately after stent implantation, and each two animals were then followed up at 2 and 4 weeks, respectively. Intravascular ultrasound (IVUS) studies were performed immediately after stent implantation and at follow-up.
  
  
  RESULTS
  Proper stent positioning and implantation was obtained in all animals. Angiographic and IVUS assessments indicated no dissection or thrombus formation. Histology demonstrated good apposition and endothelialization of the stent strut surface.
  
  
  CONCLUSIONS
  The unique flared shape of this novel ostial stent system allows for improved accuracy during stent positioning and placement, as well as complete apposition and coverage/scaffolding of the similarly-shaped luminal ostium. Future studies will determine if this novel stent system fulfills the unmet clinical need in aorto-ostial stenoses.
authors.affiliation: Division of Cardiovascular Medicine, Stanford University, Stanford, CA, USA.
authors.forename: Yoriyasu
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Ikeno
authors.forename: Jennifer K
authors.initials: JK
authors.lastname: Lyons
authors.forename: Tomomi
authors.initials: T
authors.lastname: Koizumi
authors.forename: Alan C
authors.initials: AC
authors.lastname: Yeung
mesh_terms: D000800:Angioplasty, Balloon / Q000295:instrumentation*; D000818:Animals; D001011:Aorta / Q000000981:diagnostic imaging / Q000473:pathology; D001027:Aortography; D005240:Feasibility Studies; D023421:Models, Animal; D011474:Prosthesis Design; D015641:Radiography, Interventional; D012077:Renal Artery / Q000000981:diagnostic imaging / Q000473:pathology; D012078:Renal Artery Obstruction / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy*; D012107:Research Design; D015607:Stents; D013552:Swine; D013997:Time Factors; D018084:Ultrasonography, Interventional