Transjugular intrahepatic portosystemic shunt (TIPS), a highly effective procedure reducing portal hypertension, has been in use for over seven decades and is now a cornerstone in managing portal hypertension-related complications such as variceal bleeding and ascites. Historically, TIPS has dealt with two main challenges: ensuring stent patency and preventing post-TIPS hepatic encephalopathy. The introduction of PTFE-coated stents markedly reduced the risk of TIPS dysfunction and stent patency is no longer a major concern. However, despite improved patient selection criteria, hepatic encephalopathy continues to be a significant and persistent issue. In addition, the broader application of TIPS in recent decades has brought to light additional, albeit less common, complications, such as post-TIPS heart failure. This review offers a comprehensive overview of TIPS historical evolution, advancements in technique, and its application in the treatment of portal hypertension.

This editorial describes the milestones to optimize of transjugular intrahepatic portosystemic shunt (TIPS) technique, which have made it one of the main methods for the treatment of portal hypertension complications worldwide. Innovative ideas, subsequent experimental studies and preliminary experience of use in cirrhotic patients contributed to the introduction of TIPS into clinical practice. At the moment, the main achievement in optimize of TIPS technique is progress in the qualitative characteristics of stents. The transition from bare metal stents to extended polytetrafluoroethylene-covered stent grafts made it possible to significantly prevent shunt dysfunction. However, the question of its preferred diameter, which contributes to an optimal reduction of portal pressure without the risk of developing post-TIPS hepatic encephalopathy, remains relevant. Currently, hepatic encephalopathy is one of the most common complications of TIPS, significantly affecting its effectiveness and prognosis. Careful selection of patients based on cognitive indicators, nutritional status, assessment of liver function, etc., will reduce the incidence of post-TIPS hepatic encephalopathy and improve treatment results. Optimize of TIPS technique has significantly expanded the indications for its use and made it one of the main methods for the treatment of portal hypertension complications. At the same time, there are a number of limitations and unresolved issues that require further randomized controlled trials involving a large cohort of patients.

More than five decades after it was originally conceptualized as rescue therapy for patients with intractable variceal bleeding, the transjugular intrahepatic portosystemic shunt (TIPS) procedure continues to remain a focus of intense clinical and biomedical research. By the impressive reduction in portal pressure achieved by this intervention, coupled with its minimally invasive nature, TIPS has gained increasing acceptance in the treatment of complications of portal hypertension. The early years of TIPS were plagued by poor long-term patency of the stents and increased incidence of hepatic encephalopathy. Moreover, the diversion of portal flow after placement of TIPS often resulted in derangement of hepatic functions, which was occasionally severe. While the incidence of shunt dysfunction has markedly reduced with the advent of covered stents, hepatic encephalopathy and instances of early liver failure continue to remain a significant issue after TIPS. It has emerged over the years that careful selection of patients and diligent post-procedural care is of paramount importance to optimize the outcome after TIPS. The past twenty years have seen multiple studies redefining the role of TIPS in the management of variceal bleeding and refractory ascites while exploring its application in other complications of cirrhosis like hepatic hydrothorax, portal hypertensive gastropathy, ectopic varices, hepatorenal and hepatopulmonary syndromes, non-tumoral portal vein thrombosis and chylous ascites. It has also been utilized to good effect before extrahepatic abdominal surgery to reduce perioperative morbidity and mortality. The current article aims to review the updated literature on the status of TIPS in the management of patients with liver cirrhosis.

Variceal hemorrhage is a feared complication of portal hypertension, with high rates of morbidity and mortality. Optimal management requires a thoughtful, multidisciplinary approach. In cases of refractory or recurrent esophageal hemorrhage, endovascular approaches such as transjugular intrahepatic portosystemic shunt (TIPS) have a well-defined role. For hemorrhage related to gastric varices, the optimal treatment remains to be established; however, there is increasing adoption of balloon-occluded retrograde transvenous obliteration (BRTO). This article will review the concept, history, patient selection, basic technique, and outcomes for TIPS, BRTO, and combined TIPS + BRTO procedures for variceal hemorrhage.

Transjugular Intrahepatic Portosystemic Shunt (TIPS) is used to control refractory variceal bleeding secondary to portal hypertension. This meta-analysis was conducted to systematically review polytetrafluoroethylene-covered stent grafts (CS) versus bare stents (BS) in TIPS procedure.

Systematic search of literature databases was done from January-1990 till April-2017, using predecided keywords. Outcome measures studied were (1) primary-patency (PP) at 1 year (defined as absence of shunt insufficiency at 1 year), (2) rebleeding (RE) (3) new-onset hepatic encephalopathy ([HE] new-onset or worsening encephalopathy following the procedure), and (4) survival at 1 year (SU). Odds ratio (OR) was calculated for each outcome variable. Between-study heterogeneity was assessed by the I² statistics and χ² Q-test.

Fourteen studies (4 RCTs, 2 prospective nonrandomized, and 8 retrospective) were included with 2519 patients (1548 patients in BS group and 971 patients in CS group). Three-quarter outcome measures showed significantly better results with CS. PP was pooled from 13 studies and showed an OR = 4.75 (95% confidence interval [CI] = 3.32-6.79; P < .00001; I² = 44%) in favor of CS. RE was pooled from six studies with odds ratio (OR) = 0.37(95% CI = 0.24-0.56; P < .00001; I² = 0%) in favor of CS. SU was pooled from 11 studies with OR = 1.85 (95% CI = 1.44-2.38; P < .00001; I² = 0%) in favor of CS. On subset analysis for RCTs, three outcome variables favored CS with minimal heterogeneity [PP: OR = 4.18 (95% CI = 2.66-6.55; P < .00001; I² = 0%). RE: OR = 0.43 (95% CI = 0.25-0.72; P < .001; I² = 0%). SU: OR = 1.85 (95% CI = 1.44-2.38, P < .00001; I² = 0%)]. HE showed no difference between two stents on the overall and subset pooled analysis. Overall: OR = 0.86 (95% CI = 0.68-1.08; P = .19; I² = 4%). Only RCTs: OR = 0.91 (95% CI = 0.63-1.32, P = .63; I² = 0%).

CS is associated with better primary patency and survival and lesser rate of rebleeding than BS in patients undergoing TIPS procedure. There is no difference in new-onset hepatic encephalopathy.

The incorporation, 25 years ago, of transjugular intrahepatic portosystemic shunting, better known by the acronym TIPS, represents an indisputable improvement in the treatment and management of patients with symptoms due to portal hypertension. This article discusses the origins of the technique and the technical innovations that have been progressively added through the years. The implantation of coated stents, which protect the stent from processes in the parenchymal track that can lead to stenosis, have helped ensure long-term patency, thus reducing the need for reintervention. Solid evidence from valuable publications has situated TIPS at the forefront of the treatment options in a wide variety of clinical situations associated with portal hypertension.

Although transjugular intrahepatic portosystemic shunt (TIPS) was first described in 1971, it took 15 more years for technology, in the form of expandable metallic stents, to be developed to make TIPS a viable, widespread clinical procedure. Currently, expanded polytetrafluoroethylene-covered stent grafts that exhibit significantly greater long-term patency are used for TIPS creation by most interventionalists. TIPS creation requires specific interventional skills, tools, and devices for success. In the hands of skillful, experienced interventional radiologists, TIPS creation is performed safely and successfully in greater than 95% of cases.

Incident acoustic output (IAO) dependent subharmonic signal amplitudes from ultrasound contrast agents can be categorized into occurrence, growth or saturation stages. Subharmonic aided pressure estimation (SHAPE) is a technique that utilizes growth stage subharmonic signal amplitudes for hydrostatic pressure estimation. In this study, we developed an automated IAO optimization algorithm to identify the IAO level eliciting growth stage subharmonic signals and also studied the effect of pulse length on SHAPE. This approach may help eliminate the problems of acquiring and analyzing the data offline at all IAO levels as was done in previous studies and thus, pave the way for real-time clinical pressure monitoring applications. The IAO optimization algorithm was implemented on a Logiq 9 (GE Healthcare, Milwaukee, WI) scanner interfaced with a computer. The optimization algorithm stepped the ultrasound scanner from 0% to 100% IAO. A logistic equation fitting function was applied with the criterion of minimum least squared error between the fitted subharmonic amplitudes and the measured subharmonic amplitudes as a function of the IAO levels and the optimum IAO level was chosen corresponding to the inflection point calculated from the fitted data. The efficacy of the optimum IAO level was investigated for in vivo SHAPE to monitor portal vein (PV) pressures in 5 canines and was compared with the performance of IAO levels, below and above the optimum IAO level, for 4, 8 and 16 transmit cycles. The canines received a continuous infusion of Sonazoid microbubbles (1.5 μl/kg/min; GE Healthcare, Oslo, Norway). PV pressures were obtained using a surgically introduced pressure catheter (Millar Instruments, Inc., Houston, TX) and were recorded before and after increasing PV pressures. The experiments showed that optimum IAO levels for SHAPE in the canines ranged from 6% to 40%. The best correlation between changes in PV pressures and in subharmonic amplitudes (r=-0.76; p=0.24), and between the absolute PV pressures and the subharmonic amplitudes (r=-0.89; p<0.01) were obtained for the optimized IAO and 4 transmit cycles. Only for the optimized IAO and 4 transmit cycles did the subharmonic amplitudes differ significantly (p<0.01) before and after increasing PV pressures. A new algorithm to identify optimum IAO levels for SHAPE has been developed and validated with the best results being obtained for 4 transmit cycles. The work presented in this study may pave the way for real-time clinical applications of estimating pressures using the subharmonic signals from ultrasound contrast agents.

The efficacy of using subharmonic emissions from Sonazoid microbubbles (GE Healthcare, Oslo, Norway) to track portal vein pressures and pressure changes was investigated in 14 canines using either slow- or high-flow models of portal hypertension (PH). A modified Logiq 9 scanner (GE Healthcare, Milwaukee, WI, USA) operating in subharmonic mode (f(transmit): 2.5 MHz, f(receive): 1.25 MHz) was used to collect radiofrequency data at 10-40% incident acoustic power levels with 2-4 transmit cycles (in triplicate) before and after inducing PH. A pressure catheter (Millar Instruments, Inc., Houston, TX, USA) provided reference portal vein pressures. At optimum insonification, subharmonic signal amplitude changes correlated with portal vein pressure changes; r ranged from -0.82 to -0.94 and from -0.70 to -0.73 for PH models considered separately or together, respectively. The subharmonic signal amplitudes correlated with absolute portal vein pressures (r: -0.71 to -0.79). Statistically significant differences between subharmonic amplitudes, before and after inducing PH, were noted (p ≤ 0.01). Portal vein pressures estimated using subharmonic aided pressure estimation did not reveal significant differences (p > 0.05) with respect to the pressures obtained using the Millar pressure catheter. Subharmonic-aided pressure estimation may be useful clinically for portal vein pressure monitoring.

The aim of this study was to investigate the efficacy and feasibility of local delivery of paclitaxel to inhibit pseudointimal hyperplasia/intimal hyperplasia in swine transjugular intrahepatic portosystemic shunt (TIPS) models TIPS were created in seven healthy domestic swine (15-20 kg). Before TIPS stent insertion, we performed a short-term infusion of paclitaxel (treatment group: n = 4) and saline (control group: n = 3) into the TIPS tract using a balloon catheter in which two 0.010 inch holes were created on opposite sides of the balloon. Paclitaxel or saline was given to all animals via the hepatic parenchymal and venous outflow tract. The animals were followed for up to two weeks and then killed. Gross and histological evaluations of the shunts were performed, and the maximum pseudointimal/intimal hyperplasia thicknesses were calculated for each animal The average infusion time of paclitaxel or saline was 7.6 min (6-9 min). At gross and histological evaluation, considerable pseudointimal hyperplasia had formed in the control group and statistically significant differences were found upon microscopic evaluation in the maximum pseudointimal hyperplasia thickness between the control (2.41 mm, range 1.7-3.16 mm) and animals receiving paclitaxel (0.63 mm, range 0.42-0.98 mm, p<0.05) Local delivery of paclitaxel at the time of TIPS creation may have been effective in reducing pseudointimal/intimal hyperplasia in swine TIPS models.

We wanted to evaluate the effectiveness of intraluminal irradiation with Holmium-166 ((166)Ho) for reducing the pseudointimal hyperplasia (PIH) in the transjugular intrahepatic portosystemic shunt (TIPS) tract in a swine model.

TIPS was performed in 12 domestic pigs, after the creation of portal hypertension by intraportal injection of a mixture of N-butyl-2-cyanoacrylate (NBCA) and lipiodol. Five pigs first underwent intraluminal irradiation (30 Gy) in the parenchymal tract with using a (166)Ho solution-filled balloon catheter, and this was followed by the placement of a nitinol stent in the TIPS tract. For the seven control pigs, the balloon was filled with saline and contrast media mixture. Two weeks later, follow-up portography and histological analysis were performed.

TIPS was successfully performed in all twelve pigs with achieving artificially induced portal hypertension. Portography performed two weeks after TIPS showed the patent tracts in the TIPS tracts that were irradiated with (166)Ho (5/5, 100%), whereas either completely (5/6, 83.3%) or partially (1/6, 16.7%) occluded TIPS were seen in the seven pigs of the nonirradiated control group, except in one pig that experienced periprocedural death due to bleeding. Histological analysis showed a statistically significant difference for the maximal PIH (irradiated: 32.8%, nonirradiated: 76.0%, p < 0.001) between the two groups.

Intraluminal irradiation with 30 Gy of (166)Ho for TIPS significantly improved the TIPS patency in a swine model of portal hypertension during a 2-week period of follow-up.

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.

To investigate the feasibility, safety, and efficacy of an autologous vein-covered stent (AVCS) to prevent shunt stenosis in a porcine transjugular intrahepatic portosystemic shunt (TIPS) model.

TIPS were created with an AVCS in 12 healthy domestic swine and with a bare stent in 10 additional swine. Tissue response was compared with use of venography, histology, and computerized morphometry analysis 2 weeks after implantation. Differences between AVCS and noncovered stents (established by a t-test), as well as regional differences within a single stent (established by an f test), were considered significant at P <.05.

Twenty of 22 TIPS procedures were technically successful. Ten of 12 shunts with an AVCS (83%) and two of 10 with bare stents (20%) remained patent (<50% diameter narrowing) at euthanasia 2 weeks later (P <.01). Histologic evaluation of harvested bare stents showed marked intimal hyperplasia (IH), composed of smooth muscle cells, myofibroblasts, and fibroblasts. In contrast, the AVCS were remarkably free of IH and thromboses. In patent TIPS in both groups, endothelial coverage of the luminal surface was present histologically. IH accounted for 57% (26.27/45.79) of total stent cross-sectional lumen area in the control group and 21% (8.34/39.54) in the AVCS group (P <.01), with no intrashunt differences (P >.05).

Based on short-term follow-up, AVCS significantly improved TIPS patency by prevention of both IH and in-stent thrombosis. TIPS created with an AVCS was feasible and safe in our porcine model.

Portal-systemic encephalopathy is the prototype among the neuropsychiatric disorders that fall under the term Hepatic Encephalopathies. Ammonia toxicity is central to the pathophysiology of Portal-systemic encephalopathy, and neuronal ammonia toxicity is modulated by activated astrocytes. The calcium-binding astroglial key protein S100beta is released in response to glial activation, and its measurement in serum only recently became possible. Serum S100beta was determined by an ultrasensitive ELISA in patients (n=36) with liver cirrhosis and transjugular intrahepatic portosystemic stent-shunt. Subclinical portal-systemic encephalopathy and overt portal-systemic encephalopathy were determined by age-adjusted psychometric tests and clinical staging, respectively. Serum S100beta, was specifically elevated in the presence of subclinical or early portal-systemic encephalopathy, but not arterial ammonia. S100 levels elevated above a reference value (S100beta < or = 110pg/ml) or the cut off value determined in our group of patients (112pg/ml) predicted subclinical portal-systemic encephalopathy with a specificity and sensitivity of 100 and 56.5%, respectively. Serum S100beta was significantly dependent on liver dysfunction (Child-Pugh score), but was more closely related to cognitive impairments than the score. Serum S100beta seems to be a promising biochemical surrogate marker for mild cognitive impairments due to portal-systemic encephalopathy.

The most successful transplantation site of nonencapsulated islets of Langerhans is the liver. Because usual alginate poly-L-lysine microcapsules were too large (700-1200 microm diameter) for intravascular implantations and were almost exclusively implanted intraperitoneally, the question of the preferred implantation site of microencapsulated islets has received little attention. The feasibility of implanting smaller (approximately 315 microm) alginate poly-L-lysine microcapsules into the liver and the effect of such implantations on portal pressure and liver histology was evaluated in Wistar rats. A bolus of 10,000 microcapsules of 315 microm diameter was injected intraportally (group 1; n = 22). The portal pressure increased from 6.4 +/- 1.8 mmHg to a maximum of 19 mmHg, returned to basal levels within 2 h, and remained normal after 2 months. In group 2 (n = 3), following the injection of 10,000 larger microcapsules (420 microm), the portal pressure increased to > 60 mmHg and two out of the three rats died within 3 h. When 5,000 microcapsules of 420-microm diameter were injected (group 3; n = 5), the portal pressure peaked to 30 +/- 8 mmHg and remained elevated after 4 h (12 +/- 3 mmHg), but returned to normal (8 +/- 1 mmHg) after 2 weeks. Histological studies showed normal hepatic architecture without collagen deposition into portal tracts occupied by microcapsules.

intrahepatic implantations of approximately 315-microm alginate poly-L-lysine microcapsules are feasible and safe. These results justify further investigation of this potential implantation site for microencapsulated islets.

To assess whether the use of a prosthesis covered by a Dacron sheath might prevent pseudointimal hyperplasia in a transjugular intrahepatic portosystemic shunt (TIPS).

A TIPS procedure was performed in nine pigs, after creation of a portal vein microembolization model of portal hypertension, by using a Dacron-covered nitinol stent. The first centimeter on the lower extremity of this specially made prototype was uncovered, to avoid portal vein thrombosis. Three weeks later, the seven surviving animals underwent transjugular hemodynamic and angiographic follow-up and were then killed for gross and histologic evaluation.

Shunt insertion was possible in all pigs; two died of complications of the procedure. After 3 weeks only two shunts were patent, although a 50%-60% narrowing of the initial portion of the shunt was present; the remaining shunts were occluded. Histologic examination showed pseudointimal hyperplasia associated, in the cases of occlusion, with a luminal thrombosis.

This Dacron-covered stent did not prevent pseudointima formation over the stent and resulted in a high early occlusion rate, probably related to a pronounced tissue fibrotic response likely due to Dacron-induced inflammation.

To determine whether embolization of portal vein branches would stimulate hepatocyte replication in pigs.

The portal vein branches supplying 50%-70% of the liver were embolized in eight pigs by using a combination of coils and polyvinyl alcohol particles. The extent of embolization was assessed at portography in all animals and at computed tomography in one animal. Hepatocyte replication was determined by calculating the percentage of cells that incorporated bromodeoxyuridine into their nuclei. Animals survived up to 35 days after the procedure.

Embolization of the portal vein branches supplying the left and median lobes caused transient increases of less than 70% in portal vein pressures and of less than 100% in liver enzyme levels. Indocyanine green clearance was measured in two animals and decreased less than 50%. The percentage of replicating hepatocytes in the nonembolized lobe was 0% on day 0, 7% on day 2, 14% on day 7, and 2% on day 12.

Substantial hepatocyte replication occurred 2-7 days after embolization of portal vein branches. Further research will help determine if this procedure can facilitate retroviral transduction in large animals. If successful, the low morbidity of this method may allow its use in humans for gene therapy.

Shunt dysfunction due to draining hepatic vein and/or stent stenosis is a common long-term complication of transjugular intrahepatic portosystemic shunts (TIPS). Currently, Doppler sonography is the preferred modality for routine screening of TIPS for the detection of these complications. However, this method is time-consuming, highly operator-dependent, and difficult to perform because of the anatomic attributes of the cirrhotic liver. The use of helical CT angiography (HCTA) for imaging TIPS has been recently described. HCTA of TIPS is performed after a rapid i.v. injection of a bolus of low osmolality contrast medium, followed by helical data acquisition of the region of the shunt using thin sections. The data are then reprocessed a overlapping intervals and various reformations are obtained. Preliminary reports show the sensitivity and specificity of the helical CT angiography to be comparable with Doppler sonography.

The authors attempted to determine the histologic processes that take place during development of stenosis after transjugular intrahepatic portosystemic shunt (TIPS) creation.

TIPS were created with metallic stents in 20 healthy domestic pigs (tantalum stents in 10, stainless steel stents in 10). The animals were sacrificed 2-16 days later. All the shunts were examined by means of venography both immediately after placement of the stents and before sacrifice. All histologic sections were assessed with modified Giemsa and basic fuchsin stains. Anti-smooth-muscle-cell alpha-actin stain was used in three specimens. The stenotic reaction was quantified by using standard planimetry techniques and a computerized image-analysis system.

Within 16 days after TIPS placement, 15 (75%) of the 20 shunts were completely occluded, four (20%) of 20 shunts were partially occluded, and one (5%) of 20 shunts remained widely patent (animal died of unknown cause 2 days after the TIPS procedure). Stent occlusion was caused primarily by pseudointimal hyperplasia, which was similar morphologically in the portal, middle, and hepatic portions of the stent. Myofibroblastic proliferation was the most striking feature of the pseudointimal hyperplasia. The average thickness of the proliferation was 2.14 mm, which was 67% of the total diameter of the stent. A mild fibrous or lymphocytic reaction occurred around the stent wires and between the pseudointimal hyperplasia and the liver parenchyma.

The histologic features of pseudointimal formation in this swine TIPS model closely resemble those in humans. This model may prove useful for evaluating stents and other devices and improving the understanding of restenosis after vascular interventions.

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.

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.

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).

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.

To assess the suitability of spiral Z-stents for transjugular intrahepatic portosystemic shunt (TIPS) and the influence of portal hypertension on shunt patency in young swine.

TIPS were established using spiral Z-stents in 14 domestic swine. In 7 animals, the portal venous pressure was normal; in the other 7, acute portal hypertension was induced by embolization of portal vein branches. Follow-up portal venography and histologic evaluations were done from 1 hr to 12 weeks after TIPS.

Follow-up transhepatic portal venograms showed progressive narrowing of the shunt, most prominent in the midportion of the tract. Ingrowth of liver parenchyma between the stent wires found after 3 weeks led to progressive shunt narrowing and shunt occlusion by 12 weeks. A pseudointima grew rapidly inside the stent, peaked in thickness around 4 weeks, and decreased later. Acutely created portal hypertension rapidly returned to normal and there was no difference in TIPS patency between the two groups of animals.

Although the spiral Z-stent can be used as a device for creation of TIPS in patients with cirrhotic livers, it is associated with extensive liver ingrowth in swine that leads to rapid shunt occlusion. Portal hypertension was only transient in this model.

Portal hypertension is frequently associated with secondary hypersplenism, two common clinical manifestations of which are leukopenia and thrombocytopenia. Surgical portosystemic shunts alleviate portal hypertension but their effect on hypersplenism remains unpredictable. Transjugular intrahepatic portosystemic shunt (TIPS) is a minimally invasive procedure for portal decompression. From current reports it is not clear if TIPS improves hypersplenism in patients with portal hypertension. We present a retrospective review of our experience with TIPS to determine the effect on hypersplenism.

Sixty-five patients who had a TIPS procedure between December 1991 and June 1994 were evaluated retrospectively. The records were specifically reviewed for platelet and white blood cell counts performed before the procedure, within a week after the procedure, and then again within the subsequent 3 weeks. Hypersplenism was defined as thrombocytopenia (platelet count of <100,000/mm3), leukopenia (white blood cell count of <5,000/mm3), or both.

Thrombocytopenia alone was present in 33 patients and leukopenia alone in 4 patients before TIPS was performed. Both leukopenia and thrombocytopenia were present in 12 individuals. At least one of these indices of hypersplenism was present in 49 patients. Leukocyte count improved in 11 of 16 patients (69%) whereas platelet count improved in 34 of 45 patients (75%) within a week of the procedure. In the subsequent 3 weeks, leukopenia was relieved in 5 of 10 patients (50%) and thrombocytopenia in 21 of 28 patients (75%), respectively. Of the 12 patients who had both leukopenia and thrombocytopenia before TIPS, the indices improved in 4 patients (33%) within a week of the procedure. Thrombocytopenia was more consistently corrected as opposed to leukopenia, albeit in the short term.

The TIPS procedure is a promising, minimally invasive method of portal decompression that is effective in the treatment of complications of portal hypertension including secondary hypersplenism.

Creation of presinusoidal chronic portal venous hypertension by means of repeated portal vein (PV) embolization was explored in an attempt to improve a porcine model of transjugular intrahepatic portosystemic shunt (TIPS) patency.

Six microswine underwent weekly PV embolization for 5 weeks with a total of 10.4-12.6 g of polyvinyl alcohol (PVA) particles (0.149-0.250 mm in size). Portography, liver function tests, pressure measurement in the PV and inferior vena cava (IVC) before and after PV embolization, and histopathologic evaluation of the livers were performed.

Transhepatic portal venography performed after each embolization demonstrated diffuse PV branch occlusion in all cases. At weekly follow-up, reconstitution of flow was demonstrated in these branches; permanent occlusion of PV branches was not achieved. The mean PV pressure elevated acutely from 17.3 mm Hg +/- 0.9 to 24.5 mm Hg +/- 4.2 (P < .01) after each embolization. However, the pressure always returned to baseline on the follow-up studies 1 week later. Liver function tests were normal. Histopathologic evaluation of the liver showed, in multiple PV branches, central plugs of PVA with peripheral recanalization. The liver parenchyma was otherwise normal.

Massive embolizations of PV with PVA at weekly intervals failed to create permanent portal hypertension or induce hepatic fibrosis.

We wanted to assess prospectively the safety, efficacy, and applicability of transjugular intrahepatic portosystemic shunt (TIPS) with the Strecker stent, focusing mainly on clinical and hemodynamic medium- and long-term follow-up.

Fifty-two patients reached an indication to perform a TIPS, in an emergency or after refractory variceal bleeding. It was completed in 50 of them. All presented with cirrhosis (Child C = 15, B = 23, A = 12). The prosthesis was a Strecker stent. During the follow-up, clinical, biochemical, endoscopic, ultrasound, and pressure measurement studies were performed at 1, 3, 6, 12 months. Mean follow-up was 13.5 + or - 7.8 months.

Portal pressure decreased from 32.3 + or - 8.1 (mean + or - standard deviation) to 22.3 + or - 6.7 mm Hg and portocaval gradient from 21 +/- 5.2 to 8.7 +/- 3.9 mm Hg (average, 56 + or - 16%). Shunt dysfunction was diagnosed when the portocaval gradient was >12 mm Hg (20 patients). Eleven patients (22%) presented with variceal rebleeding because of shunt dysfunction. The probability of remaining free of bleeding was 78%, 74%, and 68% at 6, 12, and 24 months, respectively. Actuarial survival rate was 91% and 86% after 12 and 18 months, respectively.

TIPS with the Strecker stent is a safe alternative for variceal bleeding. Shunt dysfunction is frequent and increases the rebleeding rate, requiring a close follow-up with pressure measurements. Randomized trials comparing stents and other alternatives are needed to fully address the role of this procedure.

The aim of this study was to assess the pathology and pathogenic mechanisms involved in the occlusion of transjugular intrahepatic portosystemic stent-shunts.

Thirty-four patients with transjugular intrahepatic portosystemic stent-shunt who had at least two portographic assessments of shunt function were the subjects of this study. The contents of any shunt demonstrating > 70% stenosis were biopsied before balloon dilatation. Further assessment was made of 10 livers obtained at either post mortem (8) or at liver transplantation (2). Cholangiography was performed in these explanted livers, which were then perfused and fixed with formaldehyde. The shunts were dissected out, sectioned, opened and the contents and the surrounding liver examined macroscopically, histopathologically and immunohistochemically.

Fourteen patients with TIPSS developed shunt stenosis. In eight patients the stenosis was greater than 70% and significant re-stenosis occurred in all at repeat portography. Three of these patients who were managed by insertion of new shunts showed no further shunt-related problems, whereas the five who were treated solely by dilatation developed further re-stenosis. Organising thrombus was found in all eight patients and bile was incorporated in the thrombus in four. Biliary epithelium was found in two. Four of the ten explanted livers showed evidence of shunt stenosis, of which three were severe and one was mild (< 70%). The occluding material in patients with severe stenosis was composed of organising thrombus containing bile and a granulomatous inflammatory response. This was associated with a transected bile duct, and the degree of stenosis was related closely to the size of the bile duct transected. The shunts free of bile showed no stenosis.

The results of this study suggest that transection of a major bile duct and bile leak play an important role in the stenosis and occlusion of the intraparenchymal portion of transjugular intrahepatic portosystemic stent-shunt. This has important implications for patient management and stent design.

TIPS is a new and exciting modality for treatment of portal hypertension and its complications. Indications for TIPS remain to be better defined in terms of efficacy and cost-benefit in relationship to other established modes of therapy of portal hypertension. Prospective, randomized controlled trials are needed for these comparisons. Until the role of TIPS in the routine management of the complications of portal hypertension is better defined, TIPS should be used only in situations in which conventional medical and endoscopic therapies have failed.

The transjugular intrahepatic portasystemic stent-shunt (TIPSS) is a side-to-side portocaval shunt, performed by interventional radiological methods, linking the hepatic and portal veins through the liver parenchyma with an expandable metal stent. The technique can be performed successfully in over 90 per cent of patients. The procedure-related mortality rate is about 1 per cent, mainly from intraperitoneal bleeding. The main indications for TIPSS insertion are control of acute variceal bleeding in patients with cirrhosis that is refractory to sclerotherapy and recurrent variceal haemorrhage despite sclerotherapy or band ligation. TIPSS insertion is followed by variceal rebleeding in about 10-20 per cent of cases, encephalopathy in 10-20 per cent, transient deterioration of liver function in 25-35 per cent and subsequent shunt dysfunction over a 6-12-month period in 15-60 per cent. The final place of TIPSS insertion in the management of portal hypertension is being evaluated in controlled studies, but its use in the treatment of uncontrolled variceal haemorrhage seems assured.

The aim of this study was to analyse prognostic variables predicting mortality, shunt insufficiency, variceal rebleeding and encephalopathy following transjugular intrahepatic portosystemic stent-shunt for variceal haemorrhage.

Sixty-eight patients with cirrhosis who successfully underwent transjugular intrahepatic portosystemic stent-shunt for variceal haemorrhage were studied. Mean age was 54.8 years (s.e. 1.5); 41 were males and 27 were females. Mean Child score was 8.3 (s.e. 0.3). Cirrhosis was alcohol related in 47. The patients have been followed up for a mean of 10.8 (s.e. 1.1) months. The univariate association between 30 prognostic variables and post-treatment encephalopathy was tested by the Chi-squared or Wilcoxon rank-sum tests and multiple logistic regression was used to test the significance of factors adjusted for one another. Cox's proportional hazard regression was used to test the univariate and multivariate significance of the other three outcomes.

Transjugular intrahepatic portosystemic stent-shunt was performed successfully in 89.5% of patients. Twenty-two patients have died and eight have been transplanted. Fourteen patients died within 30 days of transjugular intrahepatic portosystemic stent-shunt and death was predicted independently by hyponatraemia (p < 0.001) and by severe liver disease (Child C, p < 0.001). Eight patients died during follow up and survival in the long term was predicted independently by the presence of encephalopathy (p < 0.001) prior to transjugular intrahepatic portosystemic stent-shunt (p < 0.001). Shunt insufficiency was predicted by an initial portal pressure gradient of greater than 18 mmHg (p < 0.01). None of the variables analysed predicted variceal rebleeding. Encephalopathy following transjugular intrahepatic portosystemic stent-shunt was only predicted indepedently by its presence prior to transjugular intrahepatic portosystemic stent-shunt (p < 0.001).

The results of this study suggest that patients with severe liver disease and hyponatraemia are liable to die early, and the presence of encephalopathy prior to transjugular intrahepatic portosystemic stent-shunt independently determines long-term survival. Patients in these groups should be considered high risk and worked up for orthotopic liver transplantation early. Shunt function in patients with an initial portal pressure gradient of > 18 mmHg requires close supervision. Encephalopathic patients should have smaller shunts and prophylactic measures to prevent worsening encephalopathy.

Transjugular intrahepatic portosystemic shunt (TIPS) is an exciting new method for treating complications of cirrhosis. Technical advances have allowed TIPS to be widely applied in the treatment of variceal bleeding. This article presents and discusses the results of recent experiences in TIPS placement. TIPS can be successfully placed in almost all patients. The complication rate of the procedure is low. TIPS is an effective means of controlling variceal bleeding and is especially useful for controlling bleeding in patients awaiting liver transplantation. It may also have a role in the treatment of ascites and other conditions related to portal hypertension. The most important issue facing TIPS is the long-term patency of the shunt. Potential solutions to the problem of long-term shunt patency are discussed.

The authors used magnetic resonance (MR) angiography to guide catheter placement in transjugular intrahepatic portosystemic shunt (TIPS) procedures in nine of 18 patients and compared the results with those of the nine patients for whom prior planning based on MR angiography was not done. Two-dimensional time-of-flight MR venography was performed during breath hold, and projection venograms were formatted in sagittal, coronal, and axial planes. MR angiography defined venous anatomy sufficiently to shorten the procedure and help minimize invasiveness. With MR angiographic guidance, intrahepatic needle punctures were significantly fewer (without MR guidance: mean, 12.1; with MR guidance: mean, 3.6; P < .001) and associated complications were absent (without MR guidance: failed placement, n = 1; bleeding requiring blood transfusions, n = 1; death due to intraperitoneal hemorrhage with hemobilia, n = 1; and death due to hepatic capsular perforation, n = 1). The average time for the procedure was 2.9 hours without MR angiographic guidance and 1.8 hours with MR angiographic guidance (P < .001). The authors conclude that MR angiography is a useful technique for defining portal and hepatic venous anatomy before the TIPS procedure and that planning based on MR angiography may decrease the difficulty and length of the procedure.

The insertion of a transjugular intrahepatic portasystemic stent shunt (TIPSS) was evaluated in 22 patients with recurrent upper gastrointestinal haemorrhage related to portal hypertension (bleeding from oesophageal varices 10, gastric varices six, portal hypertensive gastropathy six). TIPSS was successfully performed electively in 15 patients and as an emergency in three patients. Twelve patients have had no further admissions with bleeding after TIPSS. Single episodes of bleeding were noted in six patients after TIPSS associated with shunt thrombosis (two), intimal hyperplasia within the shunt (two), and shunt migration (one). Another patient presented with reaccumulated ascites suggesting poor shunt function but died from massive variceal haemorrhage before further assessment could be performed. There was one death related to the procedure. Two patients developed encephalopathy after TIPSS, in one patient this was controlled by the insertion of a smaller diameter stent within the existing TIPSS. Several complications arose in earlier patients that have not recurred after modification of the initial technique. TIPSS can be life saving and is effective in controlling variceal haemorrhage and rebleeding from oesophageal or gastric varices and portal hypertensive gastropathy. Larger and longer term studies are required, however, to define the role of TIPSS in the overall management of such patients.

A percutaneous transjugular intrahepatic portocaval shunt (TIPS) was successfully performed using Wallstents in a 53-year-old man with neoplastic disease causing portal hypertension and life-threatening variceal hemorrhage. Shortly afterwards, recurrent hemorrhage was investigated by shunt venography which showed that extrinsic narrowing of the hepatic vein and hepatic vena cava was causing shunt thrombosis. Shunt thrombosis was cleared by balloon occlusion of the shunt and forceful retrograde flushing of thrombus into the portal circulation. The compressed hepatic vein and vena cava were then dilated and stented using Gianturco "Z" stents. Bleeding recurred 3 months later due to focal narrowing within the shunt which possibly was due to intimal proliferation. Repeat dilatation and placement of a coaxial Palmaz stent again relieved portal hypertension. Creation of a TIPS for portal hypertension secondary to neoplasm can produce valuable palliation. Complete assessment of hepatic vein and vena cava patency is required to ensure shunt function.

This study investigated the feasibility of performing an intrahepatic portacaval shunt (IHPCS) by means of transluminal laser angioplasty. In 10 anesthized dogs, a catheter was introduced into a mesenteric vein and threaded into the portal vein (PV). Under fluoroscopy, a Ross needle was passed through the PV catheter, liver, and into the intrahepatic IVC. Following guidewire exchange, a neodymium YAG laser hot-tip probe (power setting 8 W) was passed over the guidewire to accomplish a transluminal IHPCS. In five animals, an IHPCS could not be accomplished. Initial and subsequent patency was confirmed by fluoroscopy. These early data suggest that transvenous laser-induced intrahepatic portacaval shunts may be feasible as a means of decompressing portal hypertension. Further research is necessary, to investigate the long-term patency as well as this technique's ability to decompress the portal system.

An experimental swine model of acute presinusoidal portal hypertension was used to investigate the feasibility of a spiral Z stent for transjugular intrahepatic portosystemic shunt (TIPS) placement and the correlation between the shunt (stent) size and degree of portal pressure decrease.

Twelve young swine were used. Acute portal hypertension was induced by means of selective injections of absolute alcohol, ethiodized oil, and polyvinyl alcohol sponge particles into intrahepatic portal branches.

TIPS was successfully created in all swine by using spiral Z stents that were 6, 8, and 10 mm in diameter; each size stent was deployed in four animals. Being sufficiently flexible, spiral Z stents accommodated for curved shunt tracts. An average of 48% portal pressure decrease was achieved with 6-mm-diameter stents, 61% with 8-mm-diameter stents, and 87% with 10-mm-diameter stents.

These results are in agreement with our clinical experience with use of Gianturco-Rösch Z stents for TIPS formation.

The history and development of endovascular stents is described beginning with the Maass double helix spiral prosthesis, the first stent used in human clinical trials in the early 80s. This is followed by a description of the three main groups of stent techniques: the shape memory alloy stents, the balloon-expandable stents, and the self-expanding stainless steel stents. Requirements and new trends for improving clinical results in the future complete this text.

The concept of transjugular intrahepatic portosystemic stent-assisted shunt (TIPSS) using the Palmaz iliac stent has been successfully accomplished in 18 of 24 patients representing a technical success rate of 75%. Fourteen were male, 4 female with a mean age of 60 years (range 34-84 years). According to classification of Child's and Turcotte, 6 were in stage A, 6 in stage B, and 6 in stage C. Five patients were treated on an emergency basis because of massive active bleeding. In 10 patients the portosystemic tract was created between the middle hepatic vein and the right main stem of the portal vein in 8, and the left main stem in 2 patients. In 8 patients, the shunt was established between the right hepatic vein and the right main branch of the portal vein. The portosystemic gradient in 18 patients was 29.9 +/- 6 mm Hg and dropped to an average of 16.9 +/- 4 mm Hg after shunt establishment. Within the early postprocedural period of 30 days, 1 patient died of direct complications of the procedure. Because of catheter dislocation, embolization of the percutaneous transhepatic approach to the portal vein after successful shunt "creation" could not be done and was followed by intraabdominal exsanguination. One patient died of an ARDS after TIPSS. A third developed pulmonary infection. In 13 patients, because of hematomas at the puncture site of the transhepatic approach, only the transjugular approach was elected for establishing TIPSS.(ABSTRACT TRUNCATED AT 250 WORDS)

Transjugular catheterization of the portal vein can be used to form a portosystemic shunt. Conventionally, the passage of a needle from the hepatic vein into the portal vein is performed with fluoroscopic monitoring only. Several methods to target the portal vein have been previously reported, including transhepatic venous catheterization, indirect portography (arterial catheterization), or skin marking based on ultrasound (US) mapping of portal landmarks. The authors used realtime US guidance to percutaneously place a small marking wire in the parenchyma next to the portal bifurcation. A 0.018-inch-diameter, 5-mm-long platinum wire is delivered through a 22-gauge echo-tipped needle placed adjacent to the right portal vein. This marking wire enabled rapid entry into the portal vein, helped avoid extrahepatic puncture, and was useful during stent deployment and positioning.

A detailed histopathologic analysis of intrahepatic portosystemic shunts was performed following liver transplantation in five patients. Gross examination revealed that all stents were patent and unchanged in size, shape, and position from initial placement. Histologic examination at 4 days revealed an irregular luminal surface with liver parenchyma protruding between the stent wires and a single, patchy layer of endothelial cells lining the shunt surface. By 3 weeks, the stent wires were covered by a pseudointima of granulation tissue, and the luminal surface was lined with a contiguous layer of endothelial cells. Excessive pseudointimal proliferation resulted in shunt occlusion at 3 months in one patient whose shunt was subsequently reopened percutaneously.