title: Evaluation of the small intestinal submucosa covered stent in preventing restenosis after percutaneous transluminal angioplasty in the swine.
abstract: OBJECTIVE
  To compare the performance of small intestinal submucosa (SIS)-covered endografts (SCEs) to bare nitinol stents (BSs) in injured swine iliac arteries.
  
  
  METHODS
  Twenty-eight nitinol stents were used: 14 externally SCEs and 14 BSs. Devices were implanted in each side of balloon-injured external iliac arteries of 14 swine via carotid approach. Arteriograms were obtained before and after implantation and before animal sacrifice at 4, 8, and 12 weeks. Histopathological and electron microscopy studies of explanted specimens were performed.
  
  
  RESULTS
  Implantation of all SCEs and BSs was technically successful, but one SCE and one BS were obstructed at 8 weeks after implantation. At sacrifice, the other 26 stents were patent, with angiogram showing no significant different luminal narrowing between SCEs and BSs. Proliferating cell nuclear antigen (PCNA) immunohistochemistry examination revealed that the percentage of PCNA(+) cells were lower in SCEs (p<0.05). Additionally, histomorphological analysis indicated that the neointima area and percentage of narrowing area were greater in SCEs, but there was no statistical significance. Greater endothelial cell count in SCEs than in BSs per visual field at 4000 times magnification by scanning electron microscope (p<0.05).
  
  
  CONCLUSIONS
  Compared to BSs, no definite decrease of neointima and restenosis was found in SCEs in the present study. However, it is effective in promoting endothelial regeneration and strengthening endothelial function.
authors.affiliation: Department of Interventional Radiology and Vascular Surgery, The First Affiliated Hospital of Jinan University, Guangzhou, 510630, China. xiaobaiwang@163.com
authors.forename: Xiaobai
authors.initials: X
authors.lastname: Wang
authors.forename: Jinglei
authors.initials: J
authors.lastname: Li
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000497:Alloys; D000704:Analysis of Variance; D000792:Angiography; D017130:Angioplasty; D000818:Animals; D004195:Disease Models, Animal; D006083:Graft Occlusion, Vascular / Q000517:prevention & control*; D007083:Iliac Artery / Q000293:injuries / Q000601:surgery*; D007150:Immunohistochemistry; D007413:Intestinal Mucosa; D007421:Intestine, Small; D008855:Microscopy, Electron, Scanning; D011474:Prosthesis Design; D015607:Stents; D013552:Swine
chemical_list: D000497:Alloys; C013616:nitinol