Impact of PTFE-covered stent position and extension on TIPS patency.

Purpose: The objectives of this study were to determine the effects of expanded polytetrafluoroethylene (PTFE)-covered stent location and TIPS extension on primary patency.
Methods: This retrospective cohort study examined patients with PTFE-covered TIPS creation between 07/2002 and 06/2016. Clinical information and patency outcomes at 24 months were extracted. At TIPS creation, extension was performed at the discretion of the operator. Kaplan-Meier curves of primary patency were generated with conditional variables of HVO-HCJ distance, extension status, and covered versus uncovered extensions. Additional logistic regression analyses of distances were performed.
Results: Of 393 patients, 115 patients (29%) underwent stent extension, 79 (20% of total cohort) of which were at the HVO end alone. Primary patency for all TIPS was 75%, 68%, and 54% at 3, 6, and 12 months. The data endpoint were transplant or death in 92 (23%) and 116 (30%). Kaplan-Meier curves showed no statistically significant difference between the variables and primary patency at 12 and 24 months: distance up to versus greater than 10 mm (p = 0.32, 0.81); extension versus no extension (p = 0.83, 0.85); uncovered versus covered extensions (p = 0.58, 0.70). Logistic regression analyses showed a trend toward statistical significance.
Conclusion: In the setting of PTFE-covered TIPS creation, extended TIPSs and unextended well-positioned TIPSs have no difference in primary patency rates. Stent position and extension length may have an effect on primary patency, but were likely obscured by "user recognition" effects.