Transjugular intrahepatic portosystemic shunts (TIPS): effects of respiratory state and patient position on the measurement of Doppler velocities

Right vs left portal branch puncture in TIPS creation with controlled expansion covered stent: comparison of hemodynamic and clinical outcomes

PURPOSE

To retrospectively compare outcomes of TIPS performed by puncturing left portal vein (LPV) vs right portal vein (RPV) to access the portal system.

MATERIALS AND METHODS

One hundred ninety-three consecutive patients underwent TIPS with controlled expansion covered stent by using the LPV (37 patients) or the RPV (156 patients). Patients were followed until the last clinical evaluation, liver transplantation, or death.

RESULTS

Demographics and clinical characteristics of the two groups were comparable. The median follow-up was 9.6 months (range 0.1-50.6). Portosystemic pressure gradient (PSG) before TIPS 15.7 mmHg ± 4.7 in RPV group (RPVG) vs 15.4 mmHg ± 4.5 in LPV group (LPVG) (p = 0.725). After TIPS, PSG 6.3 mmHg ± 2.8 in RPVG vs 6.2 mmHg ± 2.2 (p = 0.839). In LPVG, the stent was dilated to 8-mm in 95% of patients vs 77% of RPVG (p = 0.015). Two (5.4%) and 22 (14%) patients underwent TIPS revision in LPVG and RPVG (p = 0.15). The incidence of overt HE was 13% in LPVG and 24% in RPVG (p = 0.177). Rebleeding occurred in 3 of 49 patients (6%) with variceal bleeding as an indication: 2/41 patients (4.9%) in RPVG vs 1/8 patients (12.5%) in LPVG (p = 0.417). Among 126 patients with refractory ascites 20 patients (15.9%) needed paracentesis 3 months after the procedure: 18/101 patients (17.8%) in RPVG vs 2/25 patients (8%) in LPVG (p = 0.231). Thirty-seven patients (19%) died: 32 (21%) in RPVG and 5 (14%) in LPVG (p = 0.337).

CONCLUSION

Compared with RPV puncture, in TIPS created through the LPV, the targeted PSG was reached with a smaller stent diameter. However, no significant difference in clinical outcomes was observed.

KEY POINTS

• A LPV approach for TIPS creation does not lead to better control of complications of portal hypertension as compared to a RPV approach.

Clinical outcomes of transjugular intrahepatic portosystemic shunt with PTFE-covered stents after liver transplantation and technical results in split and whole liver graft recipients

OBJECTIVES

To assess the outcomes of transjugular intrahepatic portosystemic shunt (TIPS) creation using PTFE-covered stents in liver transplant (LT) recipients and to analyze the technical result of TIPS creation in split grafts (SG) compared with whole liver grafts (WG).

METHODS AND MATERIALS

Single-center, retrospective study, analyzing LT patients who underwent TIPS using PTFE-covered stents. Clinical and technical variables were analyzed.

RESULTS

Between 2005 and 2021, TIPS was created using PTFE-covered stents in 48 LT patients at a median of 43 months (range, 0.5-192) after LT. TIPS indications were refractory ascites (RA) in 33 patients (69%), variceal bleeding (VB) in 9 patients (19%), others in 6 (12%). Ten patients (21%) received a SG. Technical success rate was 100% in both groups: in two WG recipients, (5%) a second attempt was required. An unconventional approach (combined transhepatic or transplenic access) was needed in 2 WG (5%) and 2 SG recipients (20%). Two procedure-related death occurred in the WG group. After a median follow-up of 22 months (range, 0,1-144), 16 patients (48%) in the RA group did not require post-TIPS paracentesis, in the VB group rebleeding occurred in 3 patients (33%). Fifteen patients (31%) underwent TIPS revision. Overt hepatic encephalopathy occurred in 14 patients (29%). Patient survival at 6 months, 1 year, and 3 years was 77%, 66%, and 43%, respectively.

CONCLUSIONS

The feasibility and safety of TIPS creation in SG are comparable to that of WG. TIPS creation using PTFE-covered stents represents a viable option to treat portal hypertensive complications in LT recipients.

KEY POINTS

• TIPS creation using PTFE-covered stents represents a viable option to treat complications of PH in LT recipients. • TIPS creation in LT SG recipients appears to be safe and feasible as in WG. • Results from this study may help to refine the management of LT patients with recurrent portal hypertensive complications encouraging physicians to consider TIPS creation as a treatment option in both SG and WG recipients.

Transjugular Intrahepatic Portosystemic Shunts in Patients with Cirrhosis with Refractory Ascites: Comparison of Clinical Outcomes by Using 8- and 10-mm PTFE-covered Stents

Purpose To compare the efficacy and complications of transjugular intrahepatic portosystemic shunt (TIPS) creation performed by using a 10-mm or an 8-mm-diameter polytetrafluoroethylene (PTFE)-covered stent in a consecutive series of patients with cirrhosis with refractory ascites (RA). Materials and Methods The institutional review board approved this retrospective study and informed consent was waived. One hundred seventy-one patients with RA (mean age, 58.7 years ± 10.3; 95% confidence interval [CI]: 57.2 years, 60.3 years) had undergone TIPS placement by using 10-mm (60 patients) or 8-mm (111 patients) covered stent between January 2004 and December 2012. Median follow-up time was 16.8 months (range, 3.4-84.8 months). Hemodynamic changes, incidence of hepatic encephalopathy, and long-term (>3 months) need for paracentesis after TIPS placement were evaluated and calculated by using the Kaplan-Meier method and were compared by using the log-rank test. Results Pre-TIPS demographics and clinical characteristics of the two groups were comparable. The portosystemic gradient before TIPS was 17.0 mm Hg ± 4.2 (95% CI: 15.9 mm Hg, 18.1 mm Hg) in the 10-mm group versus 16.1 mm Hg ± 3.7 (95% CI: 15.4 mm Hg, 16.8 mm Hg) in the 8-mm group (P = .164). After TIPS, the portosystemic gradient was 6.5 mm Hg ± 3.4 (95% CI: 5.7 mm Hg, 7.4 mm Hg) in the 10-mm group versus 7.5 mm Hg ± 2.6 (95% CI: 6.9 mm Hg, 7.9 mm Hg) in the 8-mm group (P = .039). The long-term need for paracentesis was greater in the 8-mm group (64 of 111 patients [58%] vs 18 of 60 patients [31%], P = .003). Overall, hepatic encephalopathy was similar in both groups (45 of 111 patients [41%] vs 26 of 60 patients [44%], P = .728). Conclusion A10-mm PTFE-covered stent leads to better control of RA secondary to portal hypertension in patients with cirrhosis, compared with an 8-mm stent, without increasing the incidence of hepatic encephalopathy. ^© RSNA, 2017.

Liver regeneration after major liver hepatectomy: Impact of body mass index

BACKGROUND

Obese patients may present with metabolic abnormalities that impact liver regeneration. We sought to assess the impact of body mass index (BMI) on liver volume regeneration index (RI) and kinetic growth rate (KGR) among patients undergoing liver resection.

METHODS

The study included 102 patients undergoing major hepatectomy (≥3 segments) between July 2004 and April 2015 and stratified the patients by preoperative BMI, number of segments resected, and postoperative remnant liver volume (RLVp) to total liver volume ratio. Resected volume at operation was subtracted from total liver volume to calculate postoperative RLVp. RI was defined as the relative increase in RLV within 2 months [(RLV2m-RLVp)/RLVp] and 7 months [(RLV7m-RLVp)/RLVp] postoperatively; KGR was calculated as RI divided by time postoperatively (weeks).

RESULTS

Median patient age was 59.6 years (interquartile range 48.1-68.7 years), and most patients were men (52.0%). Liver failure was associated with the KGR at 2 months (KGR2m) and was greater among patients with KGR2m <2.5% per week (KGR <2.5%, 18.5% vs KGR ≥ 2.5%, 4.6%; P = .04). Although RI and KGR within 2 and 7 months postoperatively were similar among all patients, after excluding patients with fibrosis, obese (0.42% per week) and overweight patients (0.29% per week) had lesser KGR2-7m compared with patients of normal BMI (0.82% per week; P < .05). Additionally, risk of a major complication was greatest among obese patients (normal weight, 8.1% vs overweight, 12.9% vs obese, 29.4%; P = .04).

CONCLUSION

BMI did not impact liver regeneration during the first 2 months. In contrast, KGR per week between 2 and 7 months postoperatively was less among overweight and obese patients.

Volumetric blood flow in transjugular intrahepatic portosystemic shunt revision using 3-dimensional Doppler sonography

OBJECTIVES

Three-dimensional (3D)/4-dimensional (4D) sonographic measurement of blood volume flow in transjugular intrahepatic porto systemic shunt revision with the intention of objective assessment of shunt patency.

METHODS

A total of 17 patients were recruited (12 male and 5 female; mean age, 55 years; range, 30-69 years). An ultrasound system equipped with a 2.0-5.0-MHz probe was used to acquire multivolume 3D/4D color Doppler data sets to assess prerevision and postrevision shunt volume flow. Volume flow was computed offline based on the principle of surface integration of Doppler-measured velocity vectors in a lateral-elevational c-surface positioned at the color flow focal depth (range, 8.0-11.5 cm). Volume flow was compared to routine measurements of the prerevision and postrevision portosystemic pressure gradient. Prerevision volume flow was compared with the outcome to determine whether a flow threshold for revision could be defined.

RESULTS

Linear regression of data from revised transjugular intrahepatic portosystemic shunt cases showed an inverse correlation between the mean-normalized change in prerevision and postrevision shunt volume flow and the mean-normalized change in the prerevision and postrevision portosystemic pressure gradient (r(2) = 0.51; P = .020). Increased shunt blood flow corresponded to a decreased pressure gradient. Comparison of prerevision flows showed preliminary threshold development at 1534 mL/min, below which a shunt revision may be recommended (P = .21; area under the receiver operating characteristic curve = 0.78).

CONCLUSIONS

Shunt volume flow measurement with 3D/4D Doppler sonography provides a potential alternative to standard pulsed wave Doppler metrics as an indicator of shunt function and predictor of revision.

Diagnostic radiology of transjugular intrahepatic portosystemic shunts

Transjugular intrahepatic portosystemic shunts (TIPS) are an effective method for treating the complications of portal hypertension. Specific indications for TIPS include secondary prevention of variceal bleeding and refractory ascites. The purpose of this review is to summarize the role of diagnostic radiology in the creation and assessment of TIPS, to highlight the complications that can occur post-TIPS, and to critically evaluate the literature regarding ultrasound evaluation of TIPS.

Yttrium-90 radioembolization for the treatment of unresectable hepatocellular carcinoma in patients with transjugular intrahepatic portosystemic shunts

PURPOSE

To evaluate the toxicity and response to radioembolization with yttrium-90 ((90)Y) glass microspheres in patients with hepatocellular carcinoma (HCC) and existing transjugular intrahepatic portosystemic shunts (TIPS).

MATERIALS AND METHODS

For treatment of unresectable HCC, 12 patients with a patent TIPS underwent a total of 21 infusions of (90)Y. Toxicity within 90 days of treatment was assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE v4.0). Imaging response within the index lesion was assessed using the World Health Organization (WHO) and European Association for the Study of the Liver (EASL) guidelines. Survival was calculated using the Kaplan-Meier method.

RESULTS

All patients had a patent TIPS on imaging before treatment. Clinical toxicities included fatigue (83%), encephalopathy (33%), and abdominal pain (25%). Three patients (25%) experienced new grade 3 or 4 bilirubin toxicity. Imaging response was achieved in 50% and 67% of patients according to WHO and EASL criteria. Six patients (50%) went on to liver transplantation. Median survival censored for liver transplantation was 498 days (95% confidence interval [CI],100-800 d), and uncensored median survival was 827 days (95% CI, 250-2,400 d).

CONCLUSIONS

(90)Y radioembolization may be a safe and effective treatment for patients with unresectable HCC and existing TIPS. This minimally embolic therapy may be particularly useful as a bridge to curative liver transplantation.

The transjugular intrahepatic portosystemic shunt (TIPS)

The creation of an intrahepatic portosystemic shunt via a transjugular approach (TIPS) is an interventional radiological procedure used to treat the complications of portal hypertension. TIPS insertion is principally indicated to prevent or arrest variceal bleeding when medical or endoscopic treatments fail, and in the management refractory ascites. This review discusses the development and execution of the technique, with focus on its clinical efficacy. Patient selection, imaging surveillance, revision techniques, and complications are also discussed.

Parâmetros dopplervelocimétricos na avaliação da perviedade da anastomose portossistêmica intra-hepática transjugular (TIPS)

A anastomose portossistêmica intra-hepática transjugular (TIPS) é um procedimento intervencionista minimamente invasivo realizado pela introdução de prótese metálica auto-expansível no parênquima hepático, via transjugular. Tem por objetivo tratar as complicações da hipertensão portal, principalmente a hemorragia digestiva alta e a ascite refratária. A estenose é complicação freqüente, embora o procedimento seja eficaz e com baixo índice de insucesso. O diagnóstico precoce da estenose é de fundamental importância, pois interfere no tipo de tratamento a ser realizado e o reaparecimento dos sintomas pode ser grave. O ultra-som Doppler é então utilizado para o seguimento dos pacientes portadores do TIPS, e vários parâmetros são descritos na literatura para o diagnóstico de estenose, como: as velocidades mínima e máxima no interior da prótese, a velocidade na veia porta, o gradiente de velocidade entre dois pontos da prótese, e outros. Infelizmente não há consenso sobre qual parâmetro ou conjunto de parâmetros é mais eficaz no diagnóstico, porque os protocolos de avaliação variam de instituição para instituição. Os autores realizaram uma revisão dos parâmetros de estenose descritos na literatura e de outros aspectos de fundamental importância na compreensão do procedimento, como as indicações, as contra-indicações e a fisiopatologia da estenose.

Parâmetros dopplervelocimétricos na avaliação da perviedade da anastomose portossistêmica intra-hepática transjugular (TIPS): estudo prospectivo

OBJETIVO: Estudar as alterações hemodinâmicas consideradas normais após a realização da anastomose portossistêmica intra-hepática transjugular (TIPS) e a eficácia dos parâmetros sugestivos de estenose do TIPS com o ultra-som Doppler. MATERIAIS E MÉTODOS: Dezesseis pacientes foram avaliados de maneira prospectiva, no período de dezembro de 2001 a março de 2003. As avaliações foram realizadas 24-48 horas após o TIPS e a seguir em intervalos regulares de 30 dias, três meses, seis meses e um ano, com ultra-som modo B, Doppler pulsado, Doppler colorido e de amplitude em diferentes pontos da prótese relacionados ao TIPS. A angiografia foi realizada apenas para a confirmação dos resultados e terapêutica pertinente. RESULTADOS: Até o momento apenas os achados de fluxo contínuo no terço proximal da prótese e o gradiente de velocidade entre dois pontos da prótese apresentaram significância estatística para o diagnóstico de estenose do TIPS (p < 0,001), mas outros diferentes critérios também estiveram presentes, porém sem significância estatística. CONCLUSÃO: O ultra-som Doppler é uma ferramenta eficaz no diagnóstico da perviedade e das complicações secundárias à realização do TIPS, sobretudo da estenose. No entanto, é necessária casuística maior, a fim de determinar um conjunto de parâmetros que facilite o seguimento destes pacientes, reservando a angiografia apenas para o tratamento pertinente.

Doppler Ultrasound Evaluation of Transjugular Intrahepatic Portosystemic Shunt Function

The current literature reflects controversy regarding the accuracy of Doppler ultrasound for the detection of transjugular intrahepatic portosystemic shunt (TIPS) malfunction. Experience has revealed many pitfalls and artifacts that can potentially interfere with the proper performance and interpretation of Doppler studies in patients with TIPS. In this article the author discusses and illustrates the spectrum of pitfalls that may be encountered during Doppler evaluation of TIPS function.

Doppler evaluation of transjugular intrahepatic portosystemic shunts

Transjugular intrahepatic portosystemic shunts are becoming an increasingly popular technique for the treatment of portal hypertension and its complications. However, to maintain patency, revisions are periodically required to treat stenosis and thrombosis. At many centers, Doppler sonography is used for routine follow-up. A variety of hemodynamic parameters, including main portal vein velocity, maximum stent velocity, minimum stent velocity, velocity gradient in the stent, temporal changes in stent velocity, flow direction in the intrahepatic portal and hepatic veins, and pulsatility of flow in the stent can be used. Many studies have confirmed that Doppler sonography is a valuable, noninvasive means of detecting stent malfunction, although the criteria vary somewhat at different institutions.

Sonography of diffuse liver disease

Sonography is often the first imaging procedure performed in the evaluation of individuals with suspected liver disease. Evaluation for biliary dilatation is always performed, because bile duct obstruction can cause abnormal liver test results, raising the suspicion of liver disease. Ultrasound is a useful but imperfect tool in evaluating diffuse liver disease. We discuss the uses and limitations of sonography in evaluating parenchymal liver disease. Sonography can show hepatomegaly, fatty infiltration of the liver, and cirrhosis, all with good but imperfect sensitivity and specificity. Sonography is of limited usefulness in acute hepatitis. Increased parenchymal echogenicity is a reliable criterion for diagnosing fatty liver. Cirrhosis can be diagnosed in the correct clinical setting when the following are present: a nodular liver surface, decreased right lobe-caudate lobe ratio, and indirect evidence of portal hypertension (collateral vessels and splenomegaly). Ultrasound plays an important role in the imaging of conditions and procedures common in patients with diffuse liver disease.

Transmitted cardiac pulsations as an indicator of transjugular intrahepatic portosystemic shunt function: initial observations

PURPOSE

To determine if cardiac pulsations are visible and quantifiable on spectral waveforms during Doppler ultrasonographic (US) evaluation of transjugular intrahepatic portosystemic shunts (TIPS), and if so, whether their magnitude declines with shunt dysfunction.

MATERIALS AND METHODS

Baseline and pre-revision US images obtained in 15 patients with venographically confirmed TIPS malfunction were retrospectively examined for spectral waveform pulsation. Cardiac pulsatility was quantified by using the venous pulsatility index (VPI), the venous equivalent of resistive index. VPIs were obtained at four locations from the main portal vein to the stent-hepatic venous junction. Baseline and follow-up examination results in 11 patients with functional TIPS acted as controls and were evaluated similarly. Baseline and follow-up mean VPIs at all four locations were compared for both sets of patients by using the Newman-Keuls pairwise multiple sample comparison test. The chi(2) test was used to determine if a VPI threshold that would result in an acceptable sensitivity and specificity for shunt dysfunction existed.

RESULTS

One hundred twenty mean VPIs were obtained in the study group, and 88 mean VPIs were obtained in the control group. Pre-revision VPIs at each location were significantly lower (P <.01) than all baseline values and than the follow-up values in the control group. A VPI less than 0.16 was 94% sensitive and 87% specific for shunt dysfunction.

CONCLUSION

The VPI, a quantitative measure of cardiac pulsation obtained with Doppler US, may be a useful parameter for assessing TIPS function.