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.
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.
Seo
Tae Seok
TS
Department of Diagnostic Radiology, Korea University Guro Hospital, Seoul, Korea.
Oh
Joo Hyeong
JH
Park
Young Koo
YK
Song
Ho Young
HY
Park
Sang Joon
SJ
Yuk
Sun Hong
SH
D000497:Alloys; D000818:Animals; D003907:Dexamethasone / Q000008:administration & dosage*; D006965:Hyperplasia; D019168:Portasystemic Shunt, Transjugular Intrahepatic; D015607:Stents; D013552:Swine
D000497:Alloys; C013616:nitinol; D003907:Dexamethasone