title: Tantalum balloon-expandable stent: in vivo swine studies.
abstract: OBJECTIVE
  The authors describe the experimental use of a balloon-expandable tantalum vascular stent in normal and atherosclerotic microswine.
  
  
  METHODS
  Thirty-one stents (15 iliac, 13 aorta, two femoral, one renal) were placed in 11 animals. Stents were placed in both normal and stenotic atherosclerotic arteries. The animals were killed and the stents explanted 2-32 weeks after placement. Arteriography was performed just prior to death in all cases.
  
  
  RESULTS
  All stents were patent arteriographically and on gross inspection. Histopathologic study showed a thin, smooth, endothelial-lined neointima over the segments with stents. This covering had a mean thickness of 2.9 x 10(-5) mm and appeared maximally developed 2-5 weeks after stent placement. The stent design incorporates the following engineering and clinical considerations: minimal profile and surface area and maximal expansion ratio, hoop strength, flexibility, fluoroscopic visibility, biocompatibility, and ease of placement. When compressed and mounted on the balloon catheter, the stent is flexible. This allows it to be easily maneuvered through tortuous or diseased vessels. On expansion, the stent becomes a semirigid tubular structure composed of multiple rhomboid cells. Stents with an expanded diameter of less than 11 mm can be introduced through a 7-F vascular sheath.
  
  
  CONCLUSIONS
  Initial results suggest that this stent successfully incorporates a number of theoretically desirable features for a vascular prosthesis, and it may offer some advantages over previously described devices.
authors.affiliation: Department of Imaging, St Agnes Medical Center, Fresno, Calif.
authors.forename: A B
authors.initials: AB
authors.lastname: Fontaine
authors.forename: M D
authors.initials: MD
authors.lastname: Dake
authors.forename: T P
authors.initials: TP
authors.lastname: Tschang
authors.forename: S
authors.initials: S
authors.lastname: Guertin
authors.forename: M T
authors.initials: MT
authors.lastname: Stabbe
authors.forename: S
authors.initials: S
authors.lastname: Dos Passos
mesh_terms: D000792:Angiography; D000800:Angioplasty, Balloon; D000818:Animals; D001011:Aorta; D001158:Arteries; D001161:Arteriosclerosis / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy; D005263:Femoral Artery; D007083:Iliac Artery; D015641:Radiography, Interventional; D012077:Renal Artery; D015607:Stents; D013552:Swine; D013635:Tantalum
chemical_list: D013635:Tantalum