title: Efficacy of a dexamethasone-eluting nitinol stent on the inhibition of pseudo-intimal hyperplasia in a transjugular intrahepatic portosystemic shunt: an experimental study in a swine model.
abstract: OBJECTIVE
  We wanted to evaluate the feasibility and efficacy of using a dexamethasone (DM)-eluting nitinol stent to inhibit the pseudo-intimal hyperplasia following stent placement in the transjugular intrahepatic portosystemic shunt tract (TIPS) of a swine.
  
  
  METHODS
  Fifteen stents were constructed using 0.15 mm-thick nitinol wire; they were 60 mm in length and 10 mm in diameter. The metallic stents were then classified into three types; type 1 and 2 was coated with the mixture of 12% and 20%, respectively, of DM solution and polyurethane (PU), while type 3 was a bare stent that was used for control study. In fifteen swine, each type of stent was implanted in the TIPS tract of 5 swine, and each animal was sacrificed 2 weeks after TIPS creation. The proliferation of the pseudo-intima was evaluated both on follow-up portogram and pathologic examination.
  
  
  RESULTS
  One TIPS case, using the type 1 stent, and two TIPS cases, using the type 2 stent, maintained their luminal patency while the others were all occluded. On the histopathologic analysis, the mean of the maximum pseudo-intimal hyperplasia was expressed as the percentage of the stent radius that was patent, and these values were 51.2%, 50% and 76% for the type 1, 2, and 3 stents, respectively.
  
  
  CONCLUSIONS
  The DM-eluting stent showed a tendency to reduce the development of pseudo-intimal hyperplasia in the TIPS tract of a swine model with induced-portal hypertension.
authors.affiliation: Department of Diagnostic Radiology, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Tae Seok
authors.initials: TS
authors.lastname: Seo
authors.forename: Joo Hyeong
authors.initials: JH
authors.lastname: Oh
authors.forename: Young Koo
authors.initials: YK
authors.lastname: Park
authors.forename: Ho Young
authors.initials: HY
authors.lastname: Song
authors.forename: Sang Joon
authors.initials: SJ
authors.lastname: Park
authors.forename: Sun Hong
authors.initials: SH
authors.lastname: Yuk
mesh_terms: D000497:Alloys; D000818:Animals; D003907:Dexamethasone / Q000008:administration & dosage*; D006965:Hyperplasia; D019168:Portasystemic Shunt, Transjugular Intrahepatic; D015607:Stents; D013552:Swine
chemical_list: D000497:Alloys; C013616:nitinol; D003907:Dexamethasone