Transjugular intrahepatic portosystemic stent-shunt (TIPSS) occlusion and the role of biliary venous fistulae

Comparison of the Covered Self-Expandable Viatorr CX Stent with the Covered Balloon-Expandable BeGraft Peripheral Stent for Transjugular Intrahepatic Portosystemic Shunt (TIPS) Creation: a Single-Centre Retrospective Study in Patients with Variceal Bleeding

PURPOSE

This study compares the safety and efficacy of the ePTFE-covered self-expansible nitinol stent (VIATORR® Controlled Expansion, Gore, Flagstaff, USA) with the ePTFE-covered, balloon-expandable, metallic stent (BeGraft peripheral, Bentley, Hechingen, Germany) for the creation of the transjugular intrahepatic portosystemic shunt (TIPS).

MATERIAL AND METHODS

From September 2016 to December 2020, 72 consecutive patients receiving TIPS for acute variceal bleeding (rescue and early TIPS, n = 15) or for prophylaxis of variceal rebleeding (n = 57) were enrolled. The main contraindications were patients with vascular liver disease (portal vein thrombosis and Budd-Chiari syndrome). Forty patients (55.6%) received a Viatorr CX stent and 32 patients (44.4%) a BeGraft peripheral stent. Safety endpoints were technical and clinical adverse events and early deaths within 30 days after TIPS implantation. Efficacy endpoints were rebleeding rates, recurrence of large varices requiring endoscopic band ligation, or TIPS revision.

RESULTS

Groups receiving the Viatorr CX or BeGraft peripheral stent were comparable in all respects except the TIPS indication for acute variceal bleeding (5% vs. 25%, p = 0.015). All patients had a successful intervention, and the physical variables of stent implantation (intervention and fluoroscopy time, reduction of the portosystemic pressure gradient) as well as adjunctive embolization of varices were similar in both groups. Severe clinical complications (Viatorr CX: 5% vs. BeGraft peripheral: 3.1%, p = 0.692), post-TIPS hepatic encephalopathy (12.5% vs. 18.8%, p = 0.743) and death (5% vs. 0%, p = 0.793) were not different between Viatorr CX and BeGraft peripheral groups. With respect to efficacy, freedom from rebleeding and from variceal band ligation during follow-up (100% vs. 100%, p = 1.0), as well as the need for shunt revision (10.5% vs. 18.8%, p = 0.327), was comparable.

CONCLUSION

Compared to the present gold standard, the Viatorr CX stent, the balloon-expandable BeGraft peripheral stent, showed similar results with respect to safety and efficacy.

Bone Marrow Endothelial Cells Take Up Blood-Borne Immune Complexes via Fcγ Receptor IIb2 in an Erythropoietin-Dependent Manner

Immune complexes (ICs) in blood are efficiently removed mainly by liver reticuloendothelial systems consisting of sinusoidal endothelial cells and Kupffer cells expressing FcγR. The bone marrow (BM) also has sinusoidal vasculatures, and sinusoidal BM endothelial cells (BMECs) bear unique function, including hematopoietic niches and traffic regulation of hematopoietic cells. In this study, we found that sinusoidal BMECs express FcγRIIb2, which is markedly increased in anemic conditions or by the administration of erythropoietin (Epo) in healthy mice. BMECs expressed Epo receptor (EpoR), and the Epo-induced increase in FcγRIIb2 expression was abolished in Epor^-/- ::HG1-Epor transgenic mice, which lack EpoR in BMECs except for BM erythroblasts, suggesting the effect was directly mediated via EpoR on BMECs. Further, although BMECs hardly captured i.v.-injected soluble ICs in healthy mice, Epo administration induced a remarkable increase in the uptake of ICs in a FcγRIIb-dependent manner. Enhancement of the IC incorporation capacity by Epo was also observed in cultured BMECs in vitro, suggesting the direct effect of Epo on BMECs. Moreover, we found that i.v.-injected ICs in Epo-treated mice were more rapidly removed from the circulation than in PBS-treated mice. These results reveal a novel function of BMECs to efficiently remove circulating blood-borne ICs in an FcγRIIb2-mediated manner.

α-Imaging Confirmed Efficient Targeting of CD45-Positive Cells After 211At-Radioimmunotherapy for Hematopoietic Cell Transplantation

α-radioimmunotherapy targeting CD45 may substitute for total-body irradiation in hematopoietic cell transplantation (HCT) preparative regimens for lymphoma. Our goal was to optimize the anti-CD45 monoclonal antibody (mAb; CA12.10C12) protein dose for (211)At-radioimmunotherapy, extending the analysis to include intraorgan (211)At activity distribution and α-imaging-based small-scale dosimetry, along with immunohistochemical staining.

METHODS

Eight normal dogs were injected with either a 0.75 (n = 5) or 1.00 (n = 3) mg/kg dose of (211)At-B10-CA12.10C12 (11.5-27.6 MBq/kg). Two were euthanized and necropsied 19-22 h after injection, and 6 received autologous HCT 3 d after (211)At-radioimmunotherapy, after lymph node and bone marrow biopsies at 2-4 and/or 19 h after injection. Blood was sampled to study toxicity and clearance; CD45 targeting was evaluated by flow cytometry. (211)At localization and small-scale dosimetry were assessed using two α-imaging systems: an α-camera and an ionizing-radiation quantum imaging detector (iQID) camera.

RESULTS

(211)At uptake was highest in the spleen (0.31-0.61% injected activity [%IA]/g), lymph nodes (0.02-0.16 %IA/g), liver (0.11-0.12 %IA/g), and marrow (0.06-0.08 %IA/g). Lymphocytes in blood and marrow were efficiently targeted using either mAb dose. Lymph nodes remained unsaturated but displayed targeted (211)At localization in T lymphocyte-rich areas. Absorbed doses to blood, marrow, and lymph nodes were estimated at 3.1, 2.4, and 3.4 Gy/166 MBq, respectively. All transplanted dogs experienced transient hepatic toxicity. Liver enzyme levels were temporarily elevated in 5 of 6 dogs; one treated with 1.00 mg mAb/kg developed ascites and was euthanized 136 d after HCT.

CONCLUSION

(211)At-anti-CD45 radioimmunotherapy with 0.75 mg mAb/kg efficiently targeted blood and marrow without severe toxicity. Dosimetry calculations and observed radiation-induced effects indicated that sufficient (211)At-B10-CA12.10C12 localization was achieved for efficient conditioning for HCT.

The transjugular intrahepatic portosystemic shunt in the treatment of portal hypertension: current status

The transjugular intrahepatic portosystemic shunt (TIPS) represents a major advance in the treatment of complications of portal hypertension. Technical improvements and increased experience over the past 24 years led to improved clinical results and a better definition of the indications for TIPS. Randomized clinical trials indicate that the TIPS procedure is not a first-line therapy for variceal bleeding, but can be used when medical treatment fails, both in the acute situation or to prevent variceal rebleeding. The role of TIPS to treat refractory ascites is probably more justified to improve the quality of life rather than to improve survival, except for patients with preserved liver function. It can be helpful for hepatic hydrothorax and can reverse hepatorenal syndrome in selected cases. It is a good treatment for Budd Chiari syndrome uncontrollable by medical treatment. Careful selection of patients is mandatory before TIPS, and clinical followup is essential to detect and treat complications that may result from TIPS stenosis (which can be prevented by using covered stents) and chronic encephalopathy (which may in severe cases justify reduction or occlusion of the shunt). A multidisciplinary approach, including the resources for liver transplantation, is always required to treat these patients.

Should stent-grafts replace bare stents for primary transjugular intrahepatic portosystemic shunts?

Transjugular intrahepatic portosystemic shunt (TIPS) creation using bare stents is a second-line treatment for complications of portal hypertension due in part to the relatively high number of reinterventions and the occurrence of new or worsened encephalopathy. Initially, custom-made stent-grafts were used for TIPS revision in cases of biliary fistulae. Subsequently, custom stent-grafts were used for de novo TIPS creation. With the introduction of the VIATORR(®) TIPS endoprosthesis a dedicated stent-graft became available for TIPS creation and revision. The VIATORR(®) demonstrated its efficacy and superiority to uncovered stents in retrospective analyses, case-matched analyses, and randomized studies. The improved patency of stent-grafts has led many to requestion the role of TIPS as a second-line therapy. Currently, randomized trials are warranted to redefine the role of TIPS in the treatment of complications of portal hypertension.

Causes of TIPS dysfunction

OBJECTIVE

Transjugular intrahepatic portosystemic shunt (TIPS) creation is an effective method to control portal hypertension. TIPS creations with bare stents have shown limited and unpredictable patency. In nearly all cases of rebleeding or recurrent ascites after TIPS creation, there is shunt stenosis or occlusion. The purpose of this article is to review the biologic and technical factors that predispose to TIPS failure and how the use of an expandable polytetrafluoroethylene (PTFE)-covered-stent has significantly improved TIPS patency.

CONCLUSION

Biologic and technical factors may predispose to shunt failure. The combination of improved technique and expandable PTFE has significantly improved TIPS patency. The need for follow-up venography and secondary interventions has been reduced significantly as a result of improved shunt patency.

Transjugular intrahepatic portosystemic stent-shunt: technical factors and new developments

The introduction of expandable metal stents in the mid 1980s led to the development of transjugular intrahepatic portosystemic stent-shunt (TIPSS) as we know it today. Short-lived detrimental effects on the hyperdynamic circulation in cirrhosis accompany the acute reduction in portal pressure following TIPSS creation. Caution is needed in patients with cardiac dysfunction or pulmonary hypertension. With increasing expertise and careful patient selection, fatal procedural complications are rare and TIPSS can even be safely used as a bridge to liver transplantation. Shunt insufficiency and hepatic encephalopathy are more common following TIPSS. Currently, however, novel approaches to tackling both these limitations exist. These include the combination of uncovered TIPSS with variceal band ligation, and the introduction of polytetrafluoroethylene covered stents. Despite the lack of controlled studies, covered stents are now widely used and have the potential to drastically reduce shunt insufficiency, the need for long-term shunt surveillance and even hepatic encephalopathy.

The natural history of parallel transjugular intrahepatic portosystemic stent shunts using uncovered stent: the role of host-related factors

OBJECTIVES

Parallel shunts (PS) are used in the management of transjugular intrahepatic portosystemic stent-shunt (TIPS) insufficiency, a major limitation of the technique. This study describes the natural history of PS, and uses them as a model to assess the role of host factors in the development of primary shunt insufficiency.

METHODS

Out of 338 patients with TIPS, 40 (11.8%) patients required insertion of a PS. Baseline and follow-up data of these patients were collected. Regular shunt surveillance involved biannual clinic visits and transjugular portography.

RESULTS

The non-PS group (group 1; n = 298) and the PS group (group 2; n = 40) had similar baseline demographic and disease characteristics. Index shunts of both groups and the PS produced a significant portal pressure gradient drop (P < 0.001), which was less in the index shunts of Group 2 (P < 0.02 for both). PS had similar cumulative shunt patency rates to those of the index shunts of Group 1, and both were greater than those of index shunts in Group 2 (P < 0.001 for both). The intervention rate (number of interventions/number of check portograms x 100) was similar for PS and the index shunts of Group 1 (38.7% and 43% respectively), but was significantly higher in the index shunts of Group 2 (85.6%; P < 0.01 for both). In Group 1 and Group 2, 144 patients (48.3%) and 21 patients (52.5%) died during follow-up after a median period of 23.4 and 8.9 months respectively.

CONCLUSIONS

These findings do not support the hypothesis that shunt insufficiency is related to host factors.

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.

MATERIALS AND 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.

CONCLUSION

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.

Improved clinical outcome with transjugular intrahepatic portosystemic stent-shunt utilizing polytetrafluoroethylene-covered stents

BACKGROUND AND AIMS

Transjugular intrahepatic portosystemic stent-shunt (TIPSS) with standard uncovered stents has a 50% one-year primary patency rate, and is complicated by hepatic encephalopathy in 35% of patients. Newer covered stents appear to have improved patency. This large study aimed to assess the shunt function and clinical efficacy of polytetrafluoroethylene-covered stents in a single centre.

METHODS

A total of 316 patients with uncovered stents before the introduction of covered stents (group 1) and 157 patients with the Viatorr Gore polytetrafluoroethylene-covered stents at the time of TIPSS creation (group 2) were studied.

RESULTS

The mean follow-up was 22.8+/-25.4 and 13.1+/-12.5 months, respectively (P<0.01). Shunt insufficiency was greater in group 1 [54 versus 8% at 12 months; relative hazard (RH) 8.6; 95% confidence interval (CI) 4.8-15.5; P<0.001]. The incidence of variceal rebleeding was greater in group 1 (11 versus 6% at 12 months; RH 2.4; 95% CI 1.1-5.1; P<0.05). The incidence of hepatic encephalopathy was greater in group 1 (32 versus 22% at 12 months; RH 1.5; 95% CI 1.1-2.3; P<0.05). Mortality was similar in the two groups.

CONCLUSION

The Viatorr type of polytetrafluoroethylene-covered stent results in vastly improved patency compared with uncovered stents, with reduced rates of variceal rebleeding and hepatic encephalopathy. This type of covered stent has the potential for superior clinical efficacy compared with uncovered stents.

Bile Resistance of Coated Transjugular Intrahepatic Portosystemic Shunt Stents in a Flow-Model

PURPOSE

We sought to test the bile resistance of transjugular intrahepatic portosystemic shunt (TIPS) stents with 3 different coatings.

MATERIALS AND METHODS

Three stents with different coating materials (monolayer polyethylene terephthalate [PETP], monolayer polytetrafluoroethylene [PTFE], and double layer [PTFE]) were tested in a flow model. After testing the sealing of the system with isotonic saline solution, fresh human bile was circulated. Constant pressure was 50 cm H2O. Bile resistance of the stent membranes was analyzed.

RESULTS

Two of the 3 stents proved completely resistant to water. Only the PETP stent was resistant to bile. The PTFE-coated stents were not bile resistant.

CONCLUSION

The bile resistance of coated TIPS stents and, thus, the dependency of TIPS shunt patency is called into question. The stent with the reported superior patency rates does not show experimental bile resistance.

[Increased long-term permeability of transjugular intrahepatic portosystemic shunt (TIPS) in 218 cirrhotic patients, with strict monitoring]

OBJECTIVE

To measure the impact of strict monitoring on long term permeability of TIPS.

METHODS

From November 1991 to December 2002, 208 patients (152 men and 66 women managed for the placing of a TIPS following failure with sclerotherapy or refractory ascites were included. The permeability of the prosthesis was controlled on the surgical piece. Revision of the TIPS was performed at the same time as the diagnosis of obstruction using trans-jugular angiography. The TIPS permeability was classified into 3 categories: primary permeability (duration of permeability recorded up until any intervention); assisted primary permeability (duration of continuous permeability with or without percutaneous intervention); secondary permeability (total duration of permeability with or without treated occlusion).

RESULTS

Among the 218 patients in the study, 108 had been monitored for less than one year (49.5%), 29 for between 1 and 2 years (13.5%), 27 between 2 and 3 years (12.5%), 16 between 3 and 4 years (7.5%), 15 between 4 and 5 years (7%) and 23 for more than 5 years (10%). The mean follow-up period was of 24.1 +/- 27.2 months (median: 13.7). Current survival of these patients was of 81.2 +/- 2.9% at 1 year, 62.9 +/- 4.2% at 3 years and 52 +/- 4.9% at 5 years. Thirty-four patients were lost to follow-up (16%), after a mean follow-up of 22.9 +/- 26.7 months (median: 9.7). All these patients exhibited a permeable TIPS during their last control. One hundred and thirty-five patients (62%) had never presented obstruction of the TIPS, with a mean follow-up of 19.5 +/- 26.2 months (median: 7.4); 83 patients (38%) exhibited 117 episodes of obstruction; 24 two episodes, 7 three and 3 more than three; 4 exhibited thrombosis provoked by an invalidating encephalopathy and contraindicating transplantation, 2 of them following a first episode of thrombosis. The current primary, primary assisted and secondary permeability rates were respectively: 67.7 +/- 3 and 514 +/- 3.7%, 79.9 +/- 2.3% and 69.3 +/- 3.4%, 94.4 +/- 1.8% and 91 +/- 2.6% at 1 and 3 years (p = 0.0001, Log Rank = 65.3). Univariate analysis revealed a relationship between the onset of an episode of early or late obstruction and the patients' age at the time the TIPS was inserted, Child's score before, and the pre- and post-surgical gradient. In multivariate analysis, none of these elements reached significance.

CONCLUSION

Although the use of TIPS in the treatment of portal hypertension follows the course of development of all surgery towards minimally invasive methods, it should not be considered as a surgical portal shunt or as a permanent treatment: long-term permeability is only obtained with strict and regular monitoring and the possibility of rapid intervention in the case of obstruction.

Transjugular Intrahepatic Portosystemic Shunts: Long-term Patency and Clinical Results in a Patient Cohort Observed for 3–9 Years

PURPOSE

To retrospectively assess the outcome of transjugular intrahepatic portosystemic shunt (TIPS) placement in a nonselected group of consecutive patients.

MATERIALS AND METHODS

TIPS placement was attempted in 82 patients. Patients were followed up for at least 3 years according to a standard protocol that included repeated shunt evaluations. Fifty-four patients underwent TIPS placement for variceal bleeding, 24 for refractory ascites, and four for other indications. Recurrent bleeding, effect on ascites, long-term patency, development of encephalopathy, and survival and complication rates were evaluated with Kaplan-Meier survival analysis and Cox multivariate analysis.

RESULTS

TIPS placement was successful in 75 patients (91%). Mean follow-up lasted 29.4 months. Primary patency was 22% and 12%, primary-assisted patency was 67% and 46%, and secondary patency was 91% and 91% at 1- and 5-year follow-up, respectively. Nonalcoholic liver disease (P =.007) and increasing platelet counts (P =.006) independently predicted development of shunt insufficiency. The 1- and 5-year rates of recurrent variceal bleeding were 21% and 27%, respectively. In the majority of patients with refractory ascites, a beneficial effect of TIPS placement was observed. The risk for encephalopathy was 25% at 1-month follow-up and 52% at 3-year follow-up. The risk for chronic or severe intermittent encephalopathy was 15% at 1-year follow-up and 20% at 3-year follow-up. Serum creatinine levels (P =.001) and age (P =.02) were independent risk factors. Overall survival rate was 61%, 49%, and 42% at 1-, 3-, and 5-year follow-up, respectively. Age (P =.03), serum albumin level (P =.02), and serum creatinine level (P <.001) were independently related to mortality.

CONCLUSION

The risk for definitive loss of shunt function was 17% at 5-year follow-up, indicating that surveillance with shunt revision-when indicated-results in excellent long-term TIPS patency. TIPS placement effectively protects against recurrent bleeding.

Polytetrafluoroethylene-covered stent grafts for TIPS procedure: 1-year patency and clinical results

OBJECTIVES

Polytetrafluoroethylene (PTFE)-covered stent grafts appear to have the potential to improve TIPS patency, but data available are few and controversial. The aim of this prospective nonrandomized trial was to assess TIPS safety and 1-yr patency with a new commercially available PTFE-covered stent graft in comparison with a group of historical controls treated with conventional stents.

METHODS

Between July 1992 and December 1999, 87 consecutive cirrhotics underwent TIPS with conventional stents, while from January 2000 to November 2001, 32 consecutive cirrhotics were treated with PTFE-covered stent grafts. All patients were followed by the same medical team according to a prospective protocol for a diagnostic work-up and a surveillance strategy.

RESULTS

The two groups were comparable for age, sex, etiology, and severity of cirrhosis. The 1-yr probability of remaining free of shunt dysfunction tended to be higher in the covered stent group: 76.3% (95% CI = 58.7-93.9%) versus 57.5% (95% CI = 46.6-68.4%); log rank test: p = 0.055. However, stenoses inside the stent were significantly higher in patients with bare stents (88% vs 17%), while stenoses at the hepatic or portal vein were more frequent in PTFE-covered stent-graft group (50% vs 9% and 33% vs 3%, respectively), (chi2 = 15.42; df = 2.0; p = 0.0004). Stenoses inside the covered portion of the stent did not occur. One-year cumulative rebleeding, encephalopathy, and survival were similar.

CONCLUSIONS

PTFE-covered stents are able to solve pseudointimal hyperplasia within the stent tract, but have a high incidence of hepatic or portal vein stenosis. Improvements in stent design and insertion techniques are necessary to fully achieve the potential benefit of this new device.

TIPS: an update

During the last 15 years the transjugular intrahepatic portosystemic shunt (TIPS) procedure has become a safe and effective treatment of portal hypertension. Its major obstacle, the high rate of shunt insufficiency, is going to be solved by the availability of covered stents showing a patency rate of up to 90%. The treatment of acute oesophageal and gastric variceal bleeding is an unsolved problem because variceal bleeding remains the major cause of death in patients with cirrhosis. TIPS has become the rescue treatment of choice because it combines high efficacy with low invasiveness. In this context, the timing of the rescue TIPS is of major importance for achieving definitive haemostasis before multi-organ failure develops. In the prevention of re-bleeding, TIPS is accepted as a second-line treatment, required in about 10-20% of patients. TIPS may be indicated when more than two significant re-bleedings occurred within a time frame of 12 months in spite of adequate first-line measures i.e. drugs or ligation. Refractory ascites is the third main indication for TIPS. Five randomized studies comparing TIPS with paracentesis show good response and comparable survival. Interpretations of authors and comments of reviewers are, however, controversial and do not permit a definitive recommendation.

Covered stents in transjugular portosystemic shunt: healing response to non-porous ePTFE covered stent grafts with and without intraluminal irradiation

The aim of this study was to evaluate the healing response to a new commercially available ePTFE-covered stent graft used to create transjugular intrahepatic portosystemic shunts (TIPS) in an animal model with and without intraluminal irradiation. The study was designed for ten domestic normotensive pigs. The TIPS was created using a ePTFE-covered stent graft (Viatorr, Gore, Flagstaff, Ariz.). Five animals were scheduled for intraluminal irradiation with iridium 192 immediately after TIPS creation with a dosage of 18 Gy. Shunt venograms were performed every 2 weeks. Animals from the irradiated and non-irradiated group were killed at 2-week intervals. Maximum follow-up was planned for 8 weeks in each group, with two animals in reserve. Gross specimen evaluation and histological examination, including scanning electron microscopy, was performed. Two animals died from interventional complications. In the irradiation group, one shunt occlusion and one stenosis occurred after 2 weeks. The stenosis regressed until the end of the 8-week follow-up period and probably was caused by a resolving thrombus. In the non-irradiated group, no shunt dysfunction was observed. One animal died early due to encephalopathy. Histology revealed an increased inflammatory reaction in the irradiation group, a lesser degree of incorporation of the stent graft, and a lesser degree of endothelialization of the inner surface compared with the non-irradiated group. No significant foreign body reaction was found at any time in any of the animals. The Viatorr stent graft was well tolerated in the pig model. Intraluminal irradiation seemed to have an adverse effect on the healing response. The TIPS patency was prolonged in both the irradiated and non-irradiated group compared with data from the literature; however, seemingly better results were observed in the non-irradiated group.

Repeat interventions for maintenance of transjugular intrahepatic portosystemic shunt function in patients with Budd-Chiari syndrome

The authors report the role of transjugular intrahepatic portosystemic shunts (TIPS) and consecutive interventions, including brachytherapy (n = 2) and stent-graft placement (n = 3), to increase secondary patency and consequently postpone orthotopic liver transplantation (OLT) in the treatment of Budd-Chiari syndrome in eight patients. Two patients (with hematologic diseases) died 2 weeks after the TIPS procedure. Median follow-up in the six survivors was 42.5 months (range, 11-79 mo). Multiple TIPS occlusions occurred in three patients (range, 2-7 revisions). Reocclusions occurred despite brachytherapy and Hemobahn stent-graft placement and necessitated OLT in one patient. Revision-free patency was achieved in the other two patients after VIATORR stent-graft placement (16 and 32 months after TIPS creation). All patients with stable TIPS (n = 5) are without ascites, no liver failure occurred, and no patients are currently on the transplant list.

TIPS is a useful long-term derivative therapy for patients with Budd-Chiari syndrome uncontrolled by medical therapy

Patients with Budd-Chiari syndrome (BCS) may require treatment with portal decompressive surgery or liver transplantation. Transjugular intrahepatic portosystemic shunt (TIPS) represents a new treatment alternative, but its long-term effect on BCS outcome has not been evaluated. Twenty-one patients with BCS consecutively admitted to our unit were evaluated. The mean follow-up was 4 +/- 3 years. Seven patients had nonprogressive forms and were successfully controlled with medical therapy; 1 case, with a short-length hepatic vein stenosis was successfully treated by angioplasty. All 8 patients are alive and asymptomatic. The remaining 13 patients, had a TIPS because of clinical deterioration (in one of them, because early TIPS thrombosis a successful side-to-side portacaval shunt [SSPCS] was performed) followed by an improvement in clinical condition. However, a patient with fulminant liver failure before TIPS insertion, died 4 months later and another patient with cirrhosis at diagnosis had liver transplantation 2 years later. The remaining 11 patients are alive and free of ascites. In 3 of these patients TIPS is patent after 3, 6, and 12 months. The remaining 8 patients developed late TIPS dysfunction. In two of these cases, after angioplasty and restenting, TIPS is patent after a follow-up of 9 and 80 months. In 5 other patients, recurring TIPS occlusion was not further corrected because no signs of portal hypertension were present. In conclusion, in patients with BCS uncontrolled with medical therapy, TIPS is a highly effective technique that is associated with long-term survival.

Creation of transjugular intrahepatic portosystemic shunts with stent-grafts: initial experiences with a polytetrafluoroethylene-covered nitinol endoprosthesis

PURPOSE

To evaluate the safety and performance of a recently developed expanded polytetrafluoroethylene (ePTFE)-covered nitinol stent-graft to create transjugular intrahepatic portosystemic shunt (TIPS) in patients with portal hypertension and related complications.

MATERIALS AND METHODS

The ePTFE-covered nitinol stent-graft was used to create TIPS in 16 patients with recurrent variceal bleeding (n = 13) or refractory ascites (n = 3). Follow-up was performed with duplex ultrasonography, clinical assessment, and venography at 6 months. Technical success and portosystemic pressure gradients (PPGs) before and after stent-graft implantation and at follow-up were assessed. Two patients died during follow-up. Histopathologic follow-up data were available for one patient at autopsy and for the other after liver transplantation.

RESULTS

The implantation technical success rate was 100%. Mean (+/- SD) PPG was reduced from 24 mm Hg +/- 5 to 9 mm Hg +/- 2. Histopathologic analysis of the explanted endoprostheses revealed no inflammatory response or neointima formation. The venographic follow-up data available for 10 patients demonstrated 100% in-graft patency (mean follow-up, 289 days +/- 26). Revisions with implantation of a new ePTFE-covered nitinol stent-graft or another commercially available stent in 10 patients were necessary because of hepatic vein stenosis above the grafted portion and/or relative diameter mismatch causing TIPS dysfunction.

CONCLUSION

The ePTFE-covered nitinol stent-graft was used successfully to create TIPS and has the potential to prolong TIPS patency upon complete coverage to the hepatocaval junction.

A new stent-graft for transjugular intrahepatic portosystemic shunts

The transjugular intrahepatic portosystemic shunt (TIPSS) has become an effective method of treatment for the complications of portal hypertension, however shunt dysfunction is common. Covered stent-grafts have been tested in animal models, and customized or "home-made" devices have been deployed in several institutions. We report the use of a new commercially available TIPSS stent-graft in six patients undergoing primary shunting as well as two cases of revision or secondary TIPSS. The device has proved relatively easy to handle and appears to have the technical features likely to improve primary patency. Further follow-up is required to properly assess shunt patency and re-intervention rates.

Intravascular US-guided direct intrahepatic portacaval shunt with a PTFE-covered stent-graft: feasibility study in swine and initial clinical results

PURPOSE

To determine the feasibility of the creation of a direct intrahepatic inferior vena cava (IVC)-to-portal-vein shunt with puncture guided by a transfemorally placed intravascular ultrasound (IVUS) probe and use of a polytetrafluoroethylene (PTFE)-covered stent-graft.

MATERIALS AND METHODS

In five swine, transjugular access was used to perform a direct puncture from the IVC to the portal vein with use of a modified Rosch-Uchida Portal Access set directed with real-time IVUS (9 MHz) introduced from a transfemoral venous approach. The direct intrahepatic portocaval shunt (DIPS) was then created with single or overlapping PTFE-covered Palmaz stents placed through a 10-F sheath and dilated to a diameter of 8 mm. Follow-up was performed with transhepatic portography at 2, 4, and 8 weeks. Animals were killed when shunts occluded or at the termination of the study at 8 weeks. Gross and microscopic histologic study was performed on sacrificed animals. A similar technique was used to create DIPS in five patients with intractable ascites, with follow-up by US and venography.

RESULTS

All experimental DIPS created in swine were created without complications. Portal vein punctures were achieved in four of five swine on the first or second pass of the needle. Follow-up transhepatic portography at 2 weeks demonstrated occlusion of two shunts, both explained by technical reasons at sacrifice. At 4 and 8 weeks, the remaining three shunts were patent on portography. Histology showed a thin neointimal lining with no significant tissue ingrowth or hyperplasia. Clinically, in five patients, successful puncture of the portal vein from the IVC was achieved in one to three passes. Creation of DIPS led to a reduction of mean portosystemic gradient from 18-29 mm Hg (mean, 24 mm Hg) to 9-10 mm Hg (mean, 9 mm Hg). One patient died of liver failure 2 days after creation of DIPS. The other four patients were doing well 2-15 months (mean, 8 months) after the procedure, with patency confirmed by US and venography.

CONCLUSION

Creation of DIPS is technically feasible, and the direct IVC-to-portal-vein puncture can be done accurately with real-time IVUS guidance. Further studies and longer follow-up are necessary to determine if the short length of the PTFE-covered stent-graft and avoidance of the hepatic vein will increase the long-term patency compared to standard transjugular intrahepatic portosystemic shunt creation.

Transjugular intrahepatic portosystemic stent-shunt insufficiency and the role of diabetes mellitus

BACKGROUND/AIMS

Maintenance of long-term patency of transjugular intrahepatic portosystemic stent-shunts (TIPSS) has proved problematic. Various prognostic variables have been assessed as predictors, but the role of diabetes mellitus, which induces vascular endothelial cell dysfunction, has not been assessed.

METHODS

We analysed the records of 248 patients who underwent TIPSS between July 1991 and July 1997, followed-up through to August 1998. Patients with at least one shunt assessment by portography and available blood glucose levels were eligible (177 patients; median follow-up, 15.0 months). Fourteen patients had a pre-procedural diagnosis of diabetes (one insulin dependent, seven oral hypoglycaemic treated and six diet controlled). In another 14 patients, diabetes was diagnosed at TIPSS insertion, giving a 28/177 (15.8%) prevalence of diabetes in our patients. Fifty-nine patients were excluded from the final analysis (including five diabetics), as they either died or had early shunt insufficiency (within 1 month of stent placement), leaving 118 patients (including 23 diabetics) to be included in the final analysis.

RESULTS

Mean age, sex distribution, median follow-up (months) and pre-shunt portal pressure gradient were comparable in the two groups (diabetics versus non-diabetics). Child-Pugh classes A and B were more common in the diabetic group (P < 0.01), and the mean inserted stent diameter was larger in the diabetic group (P < 0.05). The presence of diabetes was associated with a higher incidence of delayed shunt insufficiency (P = 0.02), but there was no evidence of an association between presence of diabetes and variceal haemorrhage post TIPSS. Kaplan-Meier analyses revealed earlier insufficiency in diabetic patients compared with those without diabetes (P = 0.04). Age, gender and presence of diabetes are included in the final logistic regression model. Individuals who have diabetes are more likely to experience shunt insufficiency independent of age and gender.

CONCLUSIONS

Diabetes mellitus is common in patients undergoing TIPSS and is associated independently with increased incidence of primary delayed shunt insufficiency.

The ADP-ribosylating CTA1-DD adjuvant enhances T cell-dependent and independent responses by direct action on B cells involving anti-apoptotic Bcl-2- and germinal center-promoting effects

We recently developed a novel immunomodulating gene fusion protein, CTA1-DD, that combines the ADP-ribosylating ability of cholera toxin (CT) with a dimer of an Ig-binding fragment, D, of Staphylococcus aureus protein A. The CTA1-DD adjuvant was found to be nontoxic and greatly augmented T cell-dependent responses to soluble protein Ags after systemic as well as mucosal immunizations. Here we show that CTA1-DD does not appear to form immune complexes or bind to soluble Ig following injections, but, rather, it binds directly to B cells of all isotypes, including naive IgD+ cells. No binding was observed to macrophages or dendritic cells. Immunizations in FcepsilonR (common FcRgamma-chain)- and FcgammaRII-deficient mice demonstrated that CTA1-DD exerted unaltered enhancing effects, indicating that FcgammaR-expressing cells are not required for the adjuvant function. Whereas CT failed to augment Ab responses to high m.w. dextran B512 in athymic mice, CTA1-DD was highly efficient, demonstrating that T cell-independent responses were also enhanced by this adjuvant. In normal mice both CT and CTA1-DD, but not the enzymatically inactive CTA1-R7K-DD mutant, were efficient enhancers of T cell-dependent as well as T cell-independent responses, and both promoted germinal center formation following immunizations. Although CT augmented apoptosis in Ag receptor-activated B cells, CTA1-DD strongly counteracted apoptosis by inducing Bcl-2 in a dose-dependent manner, a mechanism that was independent of the CD19 coreceptor. However, in the presence of CD40 stimulation, apoptosis was low and unaffected by CT, suggesting that the adjuvant effect of CT is dependent on the presence of activated CD40 ligand-expressing T cells.

Transjugular intrahepatic portosystemic shunts formed with polyethylene terephthalate-covered stents: experimental evaluation in pigs

PURPOSE

To evaluate the safety, efficacy, and tissue response associated with Wallstents covered with polyethylene terephthalate (PETP) compared with those associated with uncovered Wallstents for creation of transjugular intrahepatic portosystemic shunts (TIPS) in a porcine model.

MATERIALS AND METHODS

Thirteen TIPS were created in 13 minipigs: eight with PETP-covered Wallstents, five with standard Wallstents. Shunt venography was performed at 5-8 weeks, and necropsy was performed at 7-8 weeks. Histopathologic, immunohistochemical, and scanning electron microscopic examinations were performed.

RESULTS

Mean shunt stenoses of the control and graft groups were 45% and 53%, respectively. Graft stenoses involved the entire graft-bearing segment, whereas bare stent stenoses were localized within the liver tract. Myofibroblast and extracellular collagen matrix proliferation encompassed both control and graft-covered stents. There was one graft TIPS occlusion. One control TIPS stenosis was due to transstent proliferation of normal porcine hepatic tissue. A small focus of bile staining was seen on the abluminal surface of one TIPS, which was a patent PETP-lined shunt.

CONCLUSION

PETP graft TIPS provided equal, but not superior, patency to that of bare stent TIPS. The pattern of PETP TIPS graft healing differed from that of bare stents but was similar to that reported with other polyester graft vascular implants and consisted of diffuse transmural penetration and paving of the graft surface by extracellular collagen matrix and myofibroblasts.

Stent-grafts for de novo TIPS: technique and early results

PURPOSE

To evaluate the potential benefits of placing a polytetrafluoroethylene (PTFE)-covered stent-graft during initial creation of a transjugular intrahepatic portosystemic shunt (TIPS) in clinical practice.

MATERIALS AND METHODS

De novo TIPS were created with a PTFE stent-graft in four male and four female patients with symptomatic portal hypertension awaiting liver transplant. Their ages ranged from 35 to 62 (mean, 47) years. Patients were followed with TIPS ultrasound (US) and/or venography until liver transplantation or death; one remains under active study. Six recovered specimens underwent gross and microscopic evaluation.

RESULTS

All TIPS placements were successful. Six shunts were primarily patent, with a mean patency of 289 days, through completion of the study. Five were found to be patent at transplant and one was found to be patent at autopsy. Explant evaluation revealed a smooth, thin layer of neointima and exclusion of biliary secretions. Three patients developed a total of four stenoses (one tandem lesion) during follow-up, leading to revision in two patients. Mean primary and total patency in these patients was achieved after 279 and 463 days, respectively. A previously occult moderate stenosis was detected after explant in another patient. Only one (nonsignificant) stenosis clearly developed in an area covered by PTFE.

CONCLUSION

Placement of a de novo PTFE stent-graft during TIPS creation is feasible and may extend primary shunt patency. Appropriate positioning of the stent-graft is critical.

Primary implantation of polyester-covered stent-grafts for transjugular intrahepatic portosystemic stent shunts (TIPSS): A pilot study

PURPOSE

To investigate whether placement of a polyester-covered stent-graft increases the primary patency of transjugular intrahepatic portosystemic stent shunts (TIPSS).

METHODS

Between 1995 and 1997 Cragg Endopro or Passager MIBS stent-grafts were used for the creation of TIPSS in eight male patients, 35-59 years of age (mean 48 years). All patients suffered from recurrent variceal bleeding and/or refractory ascites due to liver cirrhosis. Seven stent-grafts were dilated to a diameter of 10 mm, one to 12 mm. Follow-up was performed with duplex ultrasound, clinical assessment, and angiography.

RESULTS

The technical success rate for creation of a TIPSS was 100%. The mean portosystemic pressure gradient decreased from 25 mmHg to 12 mmHg. In seven of eight patients TIPSS dysfunction occurred between 2 days and 3 years after stent-graft placement. In one patient the TIPSS is still primarily patent (224 days after creation). The secondary patency rates are 31 days to 3 years.

CONCLUSION

The primary use of polyester-covered stent-grafts for TIPSS did not increase primary patency rates in our small series.

Recurrent TIPS failure associated with biliary fistulae: treatment with PTFE-covered stents

PURPOSE

To evaluate the efficacy of covered stents for the treatment of transjugular intrahepatic portosystemic shunt (TIPS) obstruction in human subjects with identified or suspected biliary fistulae.

METHODS

Five patients were treated for early failure of TIPS revisions. All had mid-shunt thrombus, and four of these had demonstrable biliary fistulae. Three patients also propagated thrombus into the native portal venous system and required thrombolysis. TIPS were revised in four patients using a custom-made polytetrafluoroethylene (PTFE)-covered Wallstent, and in one patient using a custom-made PTFE-covered Gianturco Z-stent.

RESULTS

All identified biliary fistulae were successfully sealed. All five patients maintained patency and function of the TIPS during follow-up ranging from 2 days to 21 months (mean 8.4 months). No patient has required additional revision. Thrombosis of the native portal venous system was treated with partial success by mechanical thrombolysis.

CONCLUSION

Early and recurrent failure of TIPS with mid-shunt thrombosis, which may be associated with biliary fistulae, can be successfully treated using covered stents. Stent-graft revision appears to be safe, effective, and potentially durable.

Polyurethane-coated Dacron-covered stent-grafts for TIPS: results in swine

PURPOSE

To evaluate shunt patency after placing a new polyurethane-coated Dacron-covered spiral Z stent-graft to create a transjugular intrahepatic portosystemic shunt (TIPS).

METHODS

TIPS stent-grafts were placed in six young swine, using polyurethane-coated, Dacron-covered spiral Z stent-grafts. Animals were followed weekly by transhepatic portal venography until shunt occlusion or up to 6 weeks, then were sacrificed for gross and histologic evaluation.

RESULTS

Five of six TIPS stent-grafts were found to be occluded by 3 weeks and none were patent at 6 weeks. Histologic evaluation demonstrated a marked foreign body reaction with superimposed thrombosis occluding the graft lumen.

CONCLUSION

Polyurethane-coated Dacron-covered stent-grafts do not improve TIPS patency.

Prevention of transjugular intrahepatic portosystemic stent shunt thrombosis

The transjugular intrahepatic portosystemic stent shunt (TIPS) is being increasingly used in cirrhotic patients with complications of portal hypertension. Clinical trials using this nonsurgical method of decompressing the portal system have been shown to lead to control of acute variceal bleeding, prevention of recurrent hemorrhage [1–6] and improvement of ascites, refractory to medical treatment [7–9].

Patency and reintervention rates during routine TIPSS surveillance

PURPOSE

To assess the medium-term outcome of transjugular intrahepatic portosystemic stent shunts (TIPSS) by measuring the incidence of shunt obstruction or failure during routine surveillance and the number of interventions performed.

METHODS

This is a retrospective study covering a 4-year period, from 1992 to 1996, during which 102 TIPSS procedures were performed. Indications for treatment were variceal bleeding (76%) and refractory ascites (24%). Follow-up protocol after TIPSS included transfemoral or transjugular portal venography and measurement of portosystemic pressure gradient (PPG) at 3 months, 12 months, and then at yearly intervals. The results of the first 155 venograms on 62 patients (mean follow-up 14 months) have been reviewed and Kaplan-Meier analysis performed.

RESULTS

One hundred and thirty-seven of 155 (88%) examinations showed patent shunts. Fifty-six of 137 (41%) of the patent TIPSS had elevated PPG with signs of stenosis. The majority (41/56) of shunt stenoses with elevated pressure gradients were related to neointimal hyperplasia in the hepatic venous aspect of the shunt. Interventions used to reduce the pressure gradient or to restore patency included: angioplasty (62/102 interventions), additional stents (21/102), a second TIPSS procedure (2/102), and thrombolysis or thrombectomy (4/102). The primary patency rate was 66% at 1 year (52% at 2 years). Primary assisted patency was 72% at 1 year (58% at 2 years). Secondary patency was 86% at 1 year (63% at 2 years).

CONCLUSION

The majority of TIPSS shunts will remain patent when regular portal venography, with appropriate intervention, is undertaken. Although there is a high reintervention rate this mainly takes the form of balloon angioplasty.

The first decade of the transjugular intrahepatic portosystemic shunt (TIPS): state of the art

The transjugular intrahepatic portosystemic shunt (TIPS) is an interventional treatment resulting in decompression of the portal system by creation of a side-to-side portosystemic anastomosis. Since its introduction 10 years ago, more than 500 publications have appeared demonstrating rapid acceptance and increasing clinical use. This review summarizes the present knowledge of technical aspects and complications, follow-up of patients, and indications. With respect to the technique, the TIPS procedure is probably one of the most difficult interventions and, therefore, technical success and complications clearly depend on the skills of the operator. Thus, the number and kind of complications reported in this review do not necessarily relate to the procedural complications of an experienced center. The follow-up of the TIPS patient has to assess shunt patency, liver function and hepatic encephalopathy. Shunt patency can best be monitored by duplex-sonography. Routine radiological revision seems not to be helpful and does not improve results, i.e., rebleeding and survival. Short term patency may be improved by anticoagulation, while such a treatment does not influence long-term patency. With respect to the indications of TIPS, much is known about treatment of variceal bleeding. The nine randomized studies that are available to date show that survival is comparable between patients receiving TIPS or endoscopic treatment. The second group of patients is the group with refractory ascites and related complications, such as hepatorenal syndrome and hepatic hydrothorax. It has been demonstrated that TIPS improves these complications, but randomized studies are still lacking. In addition, TIPS has been applied successfully to patients with Budd-Chiari syndrome, portal vein thrombosis, before liver transplantation, and for the treatment of ectopic portal hypertensive bleeding.

Stent-grafts for revision of TIPS stenoses and occlusions: a clinical pilot study

PURPOSE

To assess the clinical and technical results of stent-graft placement for revision of transjugular intrahepatic portosystemic shunt (TIPS) stenoses and occlusions.

MATERIALS AND METHODS

Six patients who developed recurrent TIPS stenosis or occlusion of the parenchymal tract underwent shunt revision with use of polytetrafluoroethylene (PTFE) stent-grafts anchored at both ends by Z stents and centrally supported by Wallstents.

RESULTS

Before graft placement, mean primary patency was 50 days (range, 9-100 days). Patients underwent one to eight revisions with angioplasty or stent placement (mean, 3.2). Three patients had biliary-TIPS fistulas documented with use of a prototype double occlusion balloon catheter. Stent-grafts were successfully placed within the obstructed shunt, creating an excellent lumen in all cases. The portosystemic gradient was decreased from a mean of 24.3 mm Hg (range, 12-35 mm Hg) to a mean of 10.3 mm Hg (range, 7-16 mm Hg). Five of six patients were asymptomatic and no complications occurred (median clinical follow-up, 331 days). One patient died of pre-existing multi-organ system failure. The duration of primary patency after stent-grafting was improved (mean, 229 days; range, 27-324 days) and the difference approached statistical significance despite the small sample size (P = .056, paired t test). Three patients remained primarily patent at a mean venographic follow-up of 315 days. One shunt occluded at 1 month from residual thrombus in the portal vein, and one stenosis occurred that was secondary to misplacement of the original stent-graft. Patency was re-established in each of these patients.

CONCLUSION

PTFE covered stent-grafts are effective for shunt revision in patients with tract stenosis or occlusion and appear to improve TIPS patency.