title: Transjugular intrahepatic portosystemic shunt with an autologous vein-covered stent: results in a swine model.
abstract: OBJECTIVE
  To investigate the feasibility, safety, and efficacy of an autologous vein-covered stent (AVCS) to prevent shunt stenosis in a porcine transjugular intrahepatic portosystemic shunt (TIPS) model.
  
  
  METHODS
  TIPS were created with an AVCS in 12 healthy domestic swine and with a bare stent in 10 additional swine. Tissue response was compared with use of venography, histology, and computerized morphometry analysis 2 weeks after implantation. Differences between AVCS and noncovered stents (established by a t-test), as well as regional differences within a single stent (established by an f test), were considered significant at P <.05.
  
  
  RESULTS
  Twenty of 22 TIPS procedures were technically successful. Ten of 12 shunts with an AVCS (83%) and two of 10 with bare stents (20%) remained patent (<50% diameter narrowing) at euthanasia 2 weeks later (P <.01). Histologic evaluation of harvested bare stents showed marked intimal hyperplasia (IH), composed of smooth muscle cells, myofibroblasts, and fibroblasts. In contrast, the AVCS were remarkably free of IH and thromboses. In patent TIPS in both groups, endothelial coverage of the luminal surface was present histologically. IH accounted for 57% (26.27/45.79) of total stent cross-sectional lumen area in the control group and 21% (8.34/39.54) in the AVCS group (P <.01), with no intrashunt differences (P >.05).
  
  
  CONCLUSIONS
  Based on short-term follow-up, AVCS significantly improved TIPS patency by prevention of both IH and in-stent thrombosis. TIPS created with an AVCS was feasible and safe in our porcine model.
authors.affiliation: Department of Radiology, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, New Hampshire 03756, USA.
authors.forename: Z W
authors.initials: ZW
authors.lastname: Zhuang
authors.forename: P J
authors.initials: PJ
authors.lastname: Hoopes
authors.forename: P C
authors.initials: PC
authors.lastname: Koutras
authors.forename: W H
authors.initials: WH
authors.lastname: Ebbighausen
authors.forename: R J
authors.initials: RJ
authors.lastname: Wagner
authors.forename: M A
authors.initials: MA
authors.lastname: Bettmann
mesh_terms: D000818:Animals; D005240:Feasibility Studies; D006965:Hyperplasia; D007601:Jugular Veins / Q000601:surgery; D011169:Portal Vein / Q000473:pathology; D019168:Portasystemic Shunt, Transjugular Intrahepatic / Q000379:methods*; D011172:Portography; D015642:Radiology, Interventional; D015607:Stents; D013552:Swine; D017539:Tunica Intima / Q000473:pathology; D014654:Vascular Patency