Passive expansion of submaximally dilated transjugular intrahepatic portosystemic shunts and assessment of clinical outcomes

To assess for passive expansion of submaximally dilated transjugular intrahepatic portosystemic shunts (TIPS) and compare clinical outcomes with maximally dilated TIPS. PTFE-covered TIPS were created in 313 patients from July 2002 to December 2013. 230 patients had TIPS maximally dilated to 10 mm, while 43 patients had 10 mm TIPS submaximally dilated to 8 mm. Group characteristics (age, gender, MELD score, post-TIPS portosystemic gradient) and clinical outcomes (primary patency, primary assisted patency, clinical success, severe hepatic encephalopathy requiring TIPS reduction) for these patient populations were compared. 14 patients with submaximally dilated TIPS (VIATORR®) underwent follow-up computed tomography (CT) imaging, which was used to evaluate for passive expansion with 3D imaging software (TeraRecon). The two groups demonstrated no statistically significant difference in group characteristics or clinical outcomes. For the 14 patients with CT imaging, the median imaging follow-up was 373 days. There was an increase in median TIPS diameter, median percent diameter change, median area, and median percent area change in patients with CT follow-up greater than 6 months after TIPS placement compared to follow-up within 6 months (8.45 mm and 8.05 mm, 5.58% and 0.67%, 56.04 mm2 and 50.94 mm2, 11.48% and 1.34%, respectively; P < 0.01). While there was passive expansion of submaximally dilated 10 mm Viatorr® TIPS stents after 6 months, there was no difference in clinical outcomes compared to maximally dilated TIPS. Submaximal dilation may be an acceptable method to prevent complications related to overshunting in select patients, although our study found no difference in severe hepatic encephalopathy requiring TIPS reduction.