Dacron-covered stent-grafts in transjugular intrahepatic portosystemic shunts: initial experience

Shunt stenosis or occlusion after transjugular intrahepatic portosystemic shunt

Transjugular intrahepatic portosystemic shunt (TIPS) has been extensively used to treat the complications of portal hypertension and should be considered the first-line treatment for hemorrhage of acute esophagogastric varices caused by portal hypertension. However, stent stenosis or occlusion after TIPS is the main cause of shunt dysfunction and surgical failure. This paper aims to make a comprehensive review of stents, with the focus being on the development of stents and stent coat material, the reason of shunt stenosis or occlusion, and the revision of shunt.

Contrast-enhanced ultrasound: a new method for TIPS follow-up

PURPOSE

To determine the diagnostic value of contrast-enhanced ultrasound (CEUS) for the detection of TIPS (transjugular intrahepatic portosystemic shunt) complications.

MATERIALS AND METHOD

67 cirrhotic patients who underwent TIPS between 2001 and 2008 were retrospectively reviewed. Sixty-two vascular examinations in 37 patients for suspicion of TIPS dysfunction based on the clinical or radiological criteria were analyzed and compared with the 62 related Doppler and CEUS examinations obtained previously. Abnormal CEUS was defined as poor opacification of the prosthesis compared to the native portal vein, stent stenosis, hepatic vein stenosis, and occlusion of the stent.

RESULTS

Among the 62 vascular examinations, 56 were considered as pathologic, including: 20 occlusions, 25 stent stenoses, 9 hepatic vein stenoses, 1 arterial-TIPS fistula, and 1 strong flow stealing through a voluminous paraumbilical vein associated with a patent shunt. 50 were exactly correlated with a previous CEUS examination, including 20/20 occlusions (100%), 23/25 stent stenoses (91%), 5/9 hepatic vein stenoses (56%), 1/1 fistula (100%), and 1/1 strong flow stealing (100%). Two CEUS and 14 Doppler examinations were false negative.

CONCLUSION

CEUS allows direct visualization of intra-prosthetic flow, with a qualitative and anatomic study, in addition to the Doppler examination. This is a new, simple, and effective technique for TIPS follow-up.

Comparison study of Doppler ultrasound surveillance of expanded polytetrafluoroethylene-covered stent versus bare stent in transjugular intrahepatic portosystemic shunt

OBJECTIVE

This prospectively randomized controlled study aimed to assess with Doppler ultrasound (US) the shunt function of expanded polytetrafluoroethylene (ePTFE)-covered transjugular intrahepatic portosystemic shunt (TIPS) stent versus bare stent and to evaluate the usefulness of routine TIPS follow-up of ePTFE-covered stents.

METHODS

Sixty consecutive patients were randomized for bare or covered transjugular TIPS stenting in our institution between April 2007 and April 2009. Data of follow-up Doppler US, angiography, and portosystemic pressure gradient measurements were collected and analyzed.

RESULTS

The follow-up period was 8.34 + or - 4.42 months in the bare-stent group and 6.16 + or - 3.89 months in the covered-stent group. Baseline clinical characteristics were similar in both groups. Two hundred three US studies were performed in 60 patients, with a mean of 3.4 per patient, and demonstrated abnormalities in 28 patients (21 bare stents, 7 ePTFE-covered stents), 19 of them (13 in bare-stent group, 6 in covered-stent group) showing no clinical evidence of recurrence. Ten of 13 patients in the bare-stent group underwent balloon angioplasty or additional stent placement, whereas only one of six patients in the covered-stent group needed reintervention for intimal hyperplasia. The average peak velocity in the midshunt of ePTFE-covered stent was 139 + or - 26 cm/s after TIPS creation and 125 + or - 20 cm/s during follow-up, which was significantly higher than the bare-stent group (p < 0.05). The main portal vein and hepatic artery showed higher flow velocities in the ePTFE-covered stent group than in the bare-stent group. ePTFE-covered stents maintained lower portosystemic pressure gradient than bare stents (9.5 + or - 2.9 versus 13.2 + or - 1.5 mmHg, p < 0.05).

CONCLUSIONS

ePTFE-covered stents resulted in higher patency rates and better hemodynamics than bare stents. Routine US surveillance may not be necessary in patients with ePTFE-covered TIPS stent.

TIPS: comparison of shunt patency and clinical outcomes between bare stents and expanded polytetrafluoroethylene stent-grafts

PURPOSE

To compare shunt patency and clinical outcomes in two groups of patients who received a transjugular intrahepatic portosystemic shunt (TIPS): one group with bare stents and one with expanded polytetrafluoroethylene stent-grafts.

MATERIALS AND METHODS

TIPS were created with bare stents (n = 41) or stent-grafts (n = 40). Overall TIPS patency rates were compared between these two groups, as were clinical outcomes in patients with variceal bleeding and those with ascites.

RESULTS

In the bare stent group, primary shunt patency rates were 63%, 48%, and 24% at 3, 6, and 12 months, respectively. Secondary patency rates were 75% and 62% at 3 and 6 months, respectively. In the stent-graft group, primary patency rates were 94%, 67%, and 38% at 3, 6, and 12 months, respectively. Secondary patency rates were 100% and 92% at 3 and 6 months, respectively. All stent patency rates were higher in the stent-graft group, but only the difference in the 3-month primary patency rate (63% vs 94%) reached significance (P = .03). In patients with variceal bleeding as well as those with ascites, early and overall clinical success rates were higher in the stent-graft group, but only the 3-month and 12-month differences were statistically significant.

CONCLUSIONS

TIPS created with stent-grafts had better 3-month primary patency rates and better 3-month and 12-month clinical success rates compared with those created with bare stents.

A modified procedure for transjugular intrahepatic portosystemic shunt flow reduction

The authors present a modified transjugular intrahepatic portosystemic shunt (TIPS) flow reduction procedure to treat TIPS-related refractory hepatic encephalopathy, giving the results and follow-up on six patients. A 6-mm-diameter Uni Wallstent was introduced over a guide wire and deployed beyond the angulated portion of the TIPS. A Wallgraft was then introduced over the same guide wire, pushed through the Uni Wallstent coaxially, and deployed in the TIPS. All cases were technically and clinically successful. There were no deaths in the first month after the procedure. In this study, three patients had more than 1 year's patency.