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. 2026 Apr 28;7(2):91–100. doi: 10.14744/hf.2025.59487

Embolization of spontaneous portosystemic shunts for refractory hepatic encephalopathy in cirrhosis patients:A meta-analysis

Parth Patel 1, Mohamad Ebrahim 1, Eli Zaher 1, Himsikhar Khataniar 2, Priyadarshini Loganathan 3, Douglas G Adler 4,✉
PMCID: PMC13442353  PMID: 42564112

Abstract

Background and Aim

Hepatic encephalopathy is an important cause of morbidity in cirrhosis patients. The presence of spontaneous portosystemic shunts (SPSS) is associated with an increased risk of recurrent/refractory hepatic encephalopathy (HE). Embolization of SPSS has been shown to improve HE symptoms, but it may worsen portal hypertension and related complications. The aim of this study was to determine the efficacy of SPSS embolization for recurrent/refractory HE.

Materials and Methods

Five databases were screened to identify studies assessing the efficacy of SPSS embolization for HE. The random-effects model was used to calculate the pooled rates, and I2% values were used to assess heterogeneity.

Results

Twenty-one studies met the inclusion criteria, comprising a total of 331 patients with recurrent or refractory HE despite medical management. The etiology of cirrhosis included ethanol abuse, chronic viral hepatitis, MASH, and others. Following embolization, 82% of patients had HE-related clinical improvement, and 71% of patients became free from HE-related hospitalization. The mean difference in pre- and post-embolization serum ammonia levels was 104 [77-130], p<0.01. Worsening portal hypertension following embolization presented as gastrointestinal bleeding (10%), new or aggravated varices (15%), and new or aggravated ascites (15%).

Conclusion

SPSS embolization demonstrated improvement in HE-related clinical symptoms with a decreased need for hospitalization, but it exacerbates portal hypertension, increasing the risks of ascites, varices, and gastrointestinal bleeding. Future randomized controlled trials are needed to evaluate the efficacy of SPSS embolization against standard medical management.

Keywords: Cirrhosis, hepatic encephalopathy, spontaneous portosystemic shunts

Points to Note

  • Synthesis of Current Evidence: SPSS embolization improves refractory/recurrent HE, lowers ammonia, and reduces HE-related hospitalization.

  • Major Controversies: Its effect on portal hypertension remains uncertain because ascites, varices, and GI bleeding may worsen after embolization.

  • Future Directions: Larger randomized trials are needed to compare embolization with standard medical therapy and define optimal patient selection.

Introduction

Hepatic encephalopathy (HE) is a reversible syndrome encompassing neuropsychiatric pathologies resulting from the accumulation of neurotoxins in the bloodstream.[1] HE occurs in patients with acute or advanced liver disease, as well as in those with portosystemic shunting even in the absence of liver disease.

Overt HE, characterized by a noticeable decline in cognitive and neurological function, affects 30-45% of patients with cirrhosis and leads to approximately 20,000 hospitalizations annually in the United States.[2-4] Inpatient management of HE is costly, with an average of $35,000 per hospital stay.[5] Morbidity is further complicated by an increased risk of falls, the inability to safely drive, and caregiver burden.[5]

Management of HE focuses on identifying precipitating factors, administering ammonia-lowering therapies, and preventing recurrence.[6] According to the American Association for the Study of Liver Diseases (AASLD), lactulose is recommended as the first-line therapy for treating overt HE, with rifaximin added to prevent recurrence.[2]

Patients with overt HE who do not respond to medical management are classified as having refractory HE. These patients may have developed spontaneous portosystemic shunts (SPSS), which are abnormal connections between the portal vein and systemic circulation.[6] While SPSS can act as “release valves” to reduce portal pressure, they bypass normal liver blood flow, increasing the risk of recurrent or refractory HE. Embolization of large SPSS is being investigated as a potential preventive measure for HE recurrence and may offer survival benefits.[7]

Although data on the clinical performance of SPSS embolization are currently limited to case series and small studies, we conducted a meta-analysis to comprehensively evaluate the efficacy of shunt embolization in managing persistent or recurrent HE.

Materials and Methods

This study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) checklist to identify the efficacy of SPSS embolization for the management of refractory/recurrent HE (Supplementary Appendix A).

Search Strategy

The literature was searched by the authors (PP, ME) for the concepts of spontaneous portosystemic shunts, hepatic encephalopathy, embolization, portal hypertension, and cirrhosis. Search strategies were created using a combination of keywords and standardized index terms. Searches were conducted in Embase (81), Scopus (8), PubMed (103), Web of Science (58), and Medline (43). Full search strategies are provided in Supplementary Appendix B.

The titles and abstracts of the identified studies were independently screened by two authors (PP and ME). Based on predetermined inclusion and exclusion criteria, studies that did not address our specific research question were excluded. The full texts of the selected articles were then reviewed for relevant information. Any discrepancy in article selection was resolved by mutual consensus after discussion with the third co-author (EZ). Additional relevant articles were manually searched from the bibliographic section of the selected articles, as well as the systematic and narrative articles on the topic.

Study Selection

For the purpose of this meta-analysis, we included studies that evaluated the efficacy and safety of SPSS embolization for persistent or recurrent HE. Studies reporting data on adult patients (>18 years) with cirrhosis complicated by persistent or recurrent HE were included.

The exclusion criteria were as follows: (1) single-patient case reports, review articles, and editorials; (2) studies done in the pediatric (<18 years) population; (3) non-English-language studies; (4) non-human/animal studies; (5) non-clinical laboratory studies.

Data Abstraction and Quality Assessment

Two authors (E.Z. and H.K.) independently abstracted data from the studies using a pre-approved standardized form. Two authors (M.A.E., P.P.) independently assessed the quality of the studies to ascertain the risk of bias. This was done using the National Institute of Health (NIH) quality assessment tool for before-after (pre-post) studies with no control group (Table 1).

Table 1.

Characteristics of the included studies

Study ID Study type Patients (n) / Male (n) Age (mean) Etiology of cirrhosis/shunt Shunt anatomy Embolization method Embolization route Follow-up period Outcomes studied
Sakurabayashi et al.[9] 1997 Prospective 7 / 3 66 Etoh(1), HCV(4), cryptogenic(2) Splenorenal shunts(5); gastrorenal shunt(1); intrahepatic porto-hepatic vein shunt(1) Stainless steel coil (7) Percutaneous transhepatic vein(4); transrenal vein(3) 3-4 m Improvement in HE, change in ammonia level, new/worsening PHTN
Chikamori et al.[10] 2000 Case series 5 / 2 60.2±6 Etoh(2); HCV(2); crypto(2) Gastrorenal(5) 5% ethanolamine oleate with iopamidol(EOI) and absolute ethanol Transjugular retrograde obliteration (TJO) 17-74 m Improvement in HE, change in portal flow volume, change in ammonia level, new/worsening PHTN
Zidi et al.[11] 2007 Case series 7 / NR 66±9.2 HCV(4); Etoh(3) Splenorenal(7) Steel coils ± histoacryl Transfemoral(6), transhepatic (1) 3 m Improvement in HE, survival, new/worsening PHTN
Mukund et al.[12] 2012 Retrospective 7 / 7 56 MASH(2), Etoh(2), HBV(1), crypto(2) Splenorenal(7) Vascular plug or balloon occluder BRTO with sodium tetradecyl sulphate foam 4 m Improvement in HE, change in ammonia levels, new/worsening PHTN
Laleman et al.[13] 2013 Retrospective, multicenter 37 / 21 60±12.7 MASH(3), Etoh(17), HCV(13), PBC(2), AIH(1), cryptogenic(1) Splenorenal(20), meso-caval(7), periumbilical(9), meso-renal shunt(1) Coils, Amplatzer plugs, matrix Transhepatic (7); percutaneous (6); transfemoral or transjugular(23) 23±5 m Improvement in HE, new/worsening PHTN
Young et al.[14] 2013 Retrospective 8 / 2 55.5±10.1 MASH, PBC, HCV, AIH, PSC, cryptogenic NA Coil, occluder, liquid agents Common femoral vein(3); internal jugular vein(1); and transhepatic approach(3); recanalized paraumbilical vein(2) 3-28 mo; mean: 15.5±9.9 Improvement in HE, change in HE medications, new/worsening PHTN
An et al.[15] 2014 Retrospective cohort 17 / 11 61.6±2.6 HBV (9) HCV (2) Etoh(5) Others (1) Splenorenal(14); paraumbilical(3) Vascular plugs or coils + gelatin sponge Femoral vein(14); percutaneous for paraumbilical vein(3) 17 m (6–37) Improvement in HE, survival, change in liver function
Naeshiro et al.[16] 2014 Retrospective 14 / 9 68.7±5.6 HBV(1), HCV(9), alcohol(4) Splenorenal(3); gastrorenal(4), meso-caval(5); porto-caval(2) Ethanolamine oleate (EO) OR EO+coils OR EO + coils OR EO, coils + n-butyl 2-cyanoacrylate (NBCA) OR coils+NBCA Combination of these 27 (12-29 mo) Improvement in HE, change in ammonia level, new/worsening PHTN, survival
Inoue et al.[17] 2014 Retrospective 19 / 8 66.9±2.2 HCV(12), HBV(1), ALD(4), schistosomiasis (1), crypto(1) Splenorenal(19) 5% ethanolamine oleate with iopamidol(EOI) or coil occluder BRTO 28.4±2.4 m Improvement in HE, change in hepatic function reserve, survival, new/worsening PHTN
Parra-Farinas et al.[18] 2016 Prospective 35 / 18 60.7±15 MASH(4), Etoh(11), HCV(8), PBC(2), AIH(2), cryptogenic(8) Spleno-renal shunts (24), meso-caval/renal (7), gastric azygos/renal (3), recanalized paraumbilical veins (1) Coil or occluder and/or liquid agents Common femoral vein (21), internal jugular vein (9), transhepatic (3), trans-splenic approaches (1). 3-31 m Improvement in HE, new/worsening PHTN
Lynn et al.[19] 2016 Retrospective 20 / 10 60.9±8.1 MASH (8), Etoh (5), HCV (2), AIH (1), PSC (1), A1AT (1), cryptogenic (1) Splenorenal (12); IMV-ovarian (2); SMV-ovarian (1); Portal-right gonadal (1); IMV-left renal (1); Periumbilical-portosystemic (1); Multiple (2) Coil (15); occluder (4); coil+occluder (1) Transhepatic (5); right femoral vein (6); internal jugular vein (5), umbilical Vein (1); right axillary vein (3) 12 m Hospitalization requirements, change in HE medications, change in ammonia level, new/worsening PHTN
Aw et al.[20] 2017 Retrospective 7 / 5 62.5 Etoh (3), chronic hepatitis (3), MASH (1) NR Combination of a vascular plug, coils and sclerosant Retrograde transvenous obliteration. 3-6 m Improvement in HE, change in ammonia level, new/worsening PHTN
Choudhary et al.[21] 2017 Retrospective 5 / 5 61±7 MASH (3), Etoh (1), HBV (1) Splenorenal (4); mesocaval (1) Vascular plugs ± sclerosant Right femoral vein(4); right internal jugular vein (2) 9.8 m Improvement in HE, change in ammonia level, new/worsening PHTN
Philips et al.[22] 2017 Retrospective 21 / 17 56±10.6 MASH (13), Etoh (6), crypto (2) Splenorenal (17); mesocaval (7), other (6) Coil, cyanoacrylate glue PARTO, BRTO with or without cyanoacrylate glue embolization, or a combination of these 1-9 m Improvement in HE, change in ammonia levels, new/worsening PHTN
He et al.[23] 2018 Retrospective cohort 44 / 31 51.2 ± 11.6 HBV (29), HCV (2), Alcoholic liver disease (3), Others (2), Cryptogenic (8) Splenorenal (29); mesocaval(2), gastroesophageal(13), recanalized paraumbilical vein(1) Coil or vascular plug Transjugular (44) 20.7 m (15.5–31.0) Improvement in HE, new/worsening PHTN
Philips et al.[24] 2020 Retrospective 45 / 38 57.2±9.1 MASH(28), Etoh(15), HBV(1), HCV(1) Paraumbilical vein(4); coronary vein(3); splenorenal(25); multiple(13) Vascular plugs or coils or occluders ± glue Transfemoral(2); transhepatic(8); transjugular(36) 9 m Improvement in HE, change in ammonia level, new/worsening PHTN
Álvarez-Lopez et al.[25] 2022 Retrospective 5 / 3 57.1±8 HCV (4) Etoh(1) Mesocaval(2); splenorenal(2); gastroesophageal(1), gastrorenal(1) Coils + Onyx 34 (3)/ Glue + Amplatzer (1) / Coils (1) / Glue (1) Right internal jugular vein(5) 4.4 y (range 1.0-5.0) Improvement in HE, change in HE medications, new/worsening PHTN
Sahay et al.[26] 2017 Retrospective 15 / 7 NR MASH(4), Etoh(2), HCV(5), multifactorial (2), cryptogenic (2) Natural shunt or TIPS NA NA 12 m Number of hospitalizations, change in renal function, new/worsening PHTN
Fujimoto et al.[27] 2023 Retrospective cohort 30 / NR NR NR NR NR NR 24 m Improvement in HE, new/worsening PHTN
Gurtatta et al.[28] 2024 Retrospective 9 / 5 62 NR NR NR NR 3 m Improvement in HE, new/worsening PHTN
Mukund et al.[29] 2023 RCT 18 / 12 55.4±10.9 MASH(10), Etoh(3), viral(3), crypto(2) Spleno-renal(15); gastro-renal(8), large paraumbilical(5); gastro-spleno-renal shunt(3) Vascular plug or balloon occluder BRTO; PARTO 5 m Improvement in HE, change in liver volume, change in ammonia levels, new/worsening PHTN
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m: months; y: years; HBV: Hepatitis B virus; HCV: Hepatitis C virus; Etoh: Ethanol; MASH: Metabolic dysfunction associated steatohepatitis; PBC: Primary biliary cholangitis; AIH: Autoimmune hepatitis; BRTO: Balloon-occluded retrograde transvenous obliteration; PARTO: Plug-assisted retrograde transvenous obliteration; CARTO: Coil-assisted retrograde transvenous occlusion; PHTN: Portal hypertension; TIPS: Transjugular intrahepatic portosystemic shunt.

Outcomes Assessed

The outcomes assessed included clinical improvement in HE, changes in HE medication requirements, the need for HE-related hospitalization, changes in Model for End-Stage Liver Disease (MELD) score, serum ammonia levels, and serum creatinine levels. We also evaluated the development or worsening of varices and/or ascites and the incidence of gastrointestinal bleeding (GIB) following SPSS embolization for the management of persistent or recurrent HE.

Statistical Analysis

Standard meta-analysis statistics were used, following the methods suggested by DerSimonian and Laird. The pooled efficacy rates with the corresponding 95% confidence intervals (CIs) were calculated by logit transformation using a random-effects model. Heterogeneity between study-specific estimates was assessed using the Cochrane Q test and the I2 statistic. Publication bias assessment is discussed under the validation of meta-analysis. All analyses were performed using Comprehensive Meta-Analysis (CMA) software, version 4 (BioStat, Englewood, NJ).

Results

Search Results and Population Characteristics

The initial search yielded 270 references. After the removal of duplicates, a total of 194 studies, including full articles and abstracts, underwent formal title and abstract screening. Based on our inclusion and exclusion criteria, 21 studies involving a total of 331 patients were included (Fig.1).

The final analysis included 331 patients (205 male; mean age: 60.8±9.3) with recurrent or refractory HE despite medical management. The most common etiology of cirrhosis was ethanol use/abuse (30%), followed by chronic viral hepatitis (hepatitis B or hepatitis C, 30%), metabolic dysfunction-associated steatohepatitis (27%), and other causes (13%, including primary biliary cholangitis, autoimmune hepatitis, and cryptogenic cirrhosis). Mean MELD and Child-Pugh (CP) scores were 14.2±2.3 and 8.8±1.1, respectively. One or more types of shunts were present in each patient, and the most common type of shunt was splenorenal, which was present in 64% of patients. One or more procedures for SPSS embolization were performed in each patient, using techniques including, but not limited to, coils, glue, vascular plugs, and sclerosant injection via various transvenous approaches. Refer to Table 1 for the characteristics of the included studies.

Characteristics and Quality of Included Studies

Two authors (P.P. and M.E.) conducted an independent and blinded quality assessment of the included studies. Despite encountering some discrepancies, these were resolved by a third author (P.L.) in an independent and blinded manner. Our systematic review employed three types of quality assessment using the NIH scale: pre-post studies without control groups, controlled intervention studies, and case series assessments. The NIH scale was chosen for its comprehensive evaluation criteria suitable for diverse study designs.[8] According to the NIH scale, eleven studies received a score of 9, indicating high quality, whereas seven studies were deemed to be of fair quality, with scores ranging from 5 to 8, as shown in Supplementary Table 1 and Table 2. Fair-quality studies had insufficient data, as they were based on abstracts rather than full-text articles. Despite this limitation, these abstracts were included because of their relevance to the research question and the lack of available full-text studies. In the case series studies, two of the included studies were regarded as high quality. Regarding the randomized controlled trial, one study was deemed high quality, with 11 points out of 14 in different aspects, as per the NIH quality assessment for controlled intervention trials.

Table 2.

Pooled outcomes

Outcomes Percentage (%) Mean difference I2% Studies (n)
Improvement in HE symptoms/clinical success 81.7 (73–87) – 46 19
Free from HE medications 12.3 (3–37) – 58 5
Decrease in need for HE medications 17.5 (7–35) – 42 5
Free from HE related hospitalizations 71.7 (48–87) – 55 6
No change in HE medications 22.0 (7–51) – 67 5
Development of new or worsening of pre-existing ascites 15.4 (11–21) – 2.5 16
Development of new or worsening of pre-existing varices 14.8 (8–26) – 62 16
Post-embolization gastrointestinal bleeding 10.0 (6–16) – 11 13
Post-embolization syndrome (fever and leukocytosis) 15.2 (6–32) – 70 12
Serum creatinine – -0.17 (-0.4–0.03), p=0.09 56 5
Serum ammonia – 104 (77–130), p<0.001 77 7
MELD score – 0.4 (-2.5–3.4), p=0.7 96 5
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HE: Hepatic encephalopathy; MELD: Model for end stage liver disease.

Pooled Outcomes

Clinical Success

Nineteen of 21 studies reported HE-related clinical improvement. A total of 261 (82%) patients experienced improvement in HE symptoms following one or more embolization procedures (I2=46%) (Fig. 2). Six studies reported the need for HE-related hospitalization following embolization (Supplementary Fig. 1). A total of 53 (71%) patients became free from HE-related hospitalization (I2=55%). The change in serum ammonia level was reported by seven studies. There was a significant reduction noted between pre- and post-embolization serum ammonia levels (mean difference=104 [77-130] mcg/dl, p<0.01, I2=77%) (Fig. 3). There was no significant difference in pre- and post-embolization MELD scores (0.428 [-2.5-3.3], p=0.8) in 5 studies (Table 2).

Figure 2.

Figure 2

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Clinical success.

Figure 1.

Figure 1

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Study selection flow chart.

Figure 3.

Figure 3

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Mean difference in serum ammonia.

Adverse Events

Sixteen studies reported the incidence of new or worsening portal hypertension following embolization. A total of 33 (15%) patients developed new or aggravated esophageal and/or gastric varices (I2=62%), and 34 (15%) patients developed new or worsening ascites (I2=2.5%) (Supplementary Fig. 2). The post-embolization course was complicated by gastrointestinal bleeding in 15 (10%) patients, as reported by 13 studies (I2=11%) (Fig. 4). A total of 26 (15%) patients from 12 studies developed post-embolization fever and/or leukocytosis (I2=70%). No significant difference was noted between pre- and post-embolization serum creatinine levels (mean difference=0.17 [-0.36-0.03] mg/dl, p=0.09, I2=56%) (Table 2).

Figure 4.

Figure 4

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Post-embolization gastrointestinal bleeding.

Validation of Meta-Analysis

Sensitivity Analysis

To assess whether any one study had a dominant effect on the meta-analysis, we excluded one study at a time and analyzed its effect on the main summary estimate. No single study significantly affected the outcome or heterogeneity.

Heterogeneity

We assessed the dispersion of the calculated rates using the I2 percentage values. Based on I2 analysis for heterogeneity, considerable heterogeneity was noted for the pooled difference in the pre- and post-embolization change in serum ammonia level and MELD score. The I2 values for the pooled rates are summarized in Table 2.

Prediction Interval

This meta-analysis was conducted using the random-effects model. Therefore, we calculated the prediction interval, which deals with the dispersion of the effects. The calculated prediction interval for the difference in means between pre- and post-embolization ammonia was 104 (95% interval, 18.5 to 189.5), and for new or aggravated varices, it was 0.148 (95% interval, 0.016 to 0.656).

Publication Bias

Based on visual inspection of the funnel plot, as well as quantitative measurement using the Egger regression test, there is evidence of publication bias for pre- and post-embolization ammonia (Egger’s 2-tailed p-value=0.04). There is also evidence of publication bias for overall clinical success (Egger’s 2-tailed p-value=0.001). The funnel plot for publication bias is illustrated in Supplementary Figure 3.

Discussion

This study evaluated the efficacy of SPSS embolization for patients with HE refractory to medical management. A total of 21 studies meeting the inclusion criteria were analyzed. SPSS embolization demonstrated efficacy through clinical improvement in HE symptoms, reduced need for HE-related hospitalization, and a statistically significant decrease in ammonia levels. Adverse events included post-embolization fever/leukocytosis, GIB, and the development or worsening of pre-existing esophageal or gastric varices and/or ascites.

In our analysis of 19 studies, 82% of patients had clinical improvement in persistent or recurrent HE, reported as an increase in autonomy, improvement in cognitive symptoms, and a decrease in the need for HE medications after SPSS embolization. GIB and the development of new or exacerbated varices were reported in 10% and 15% of patients, respectively, following embolization. GIB following embolization may result from worsened portal hypertension or the progression of underlying cirrhosis. However, it is unclear whether SPSS embolization directly worsens portal hypertension, as the relationship between SPSS and the risk of GIB remains ambiguous.[30-32]

In our study, 15% of patients developed new-onset ascites or experienced a worsening of pre-existing ascites after SPSS embolization, likely due to increased portal hypertension. A recent study found that an elevation of the hepatic venous pressure gradient (HVPG) by >4 mm Hg from baseline and an absolute increase to >16 mm Hg immediately post-embolization were significant predictors of early- and late-onset ascites, respectively.[33]

Overt HE is one of the major complications of transjugular intrahepatic portosystemic shunt (TIPS).[34] Moreover, the presence of SPSS further increases the risk of overt HE following TIPS.[35] In their meta-analysis, Yang et al.[35] reported an increased risk of overt HE in patients undergoing TIPS without concurrent SPSS embolization compared to those with concurrent SPSS embolization, with no significant differences in mortality, variceal bleeding, or shunt dysfunction. A recent meta-analysis reported a decreased risk of overt HE in patients undergoing TIPS along with concurrent large SPSS embolization compared to TIPS alone, without a significant increase in recurrent variceal bleeding.[36] Our findings are consistent with these studies in that SPSS embolization decreases the risk of recurrent/refractory HE in patients with or without TIPS.

The presence and size of SPSS increased with liver dysfunction, as indicated by higher MELD scores.[37] Our analysis revealed no significant difference in MELD scores before and after SPSS embolization (Table 2). However, the MELD score does not account for post-SPSS embolization complications related to portal hypertension, and its impact on other serious outcomes remains uncertain.[7]

In our analysis, 15% of patients developed fever and/or leukocytosis following SPSS embolization. Post-embolization fever is a common occurrence, primarily attributed to transient bacteremia following the injection of sclerosing agents.[38] In the majority of patients, fever subsided with conservative management.

To our knowledge, this is the first meta-analysis investigating the efficacy of SPSS embolization for patients with persistent or recurrent HE. This analysis includes a diverse patient population with various shunt types and encompasses different embolization techniques. Given that embolization remains a key treatment option for many patients in the absence of liver transplantation, our results demonstrating acceptable levels of heterogeneity are particularly significant. This consistency across the included studies enhances the robustness of our findings in this patient group.

Our study is constrained by the following limitations. First, the prevalence of retrospective studies introduces inherent biases from historical data, which may affect the robustness of our findings. Second, 6 out of 21 studies included in the analysis originate from conference abstracts, which, by their nature, lack the comprehensive scrutiny and peer-review process characteristic of full-length publications. Third, the limited data on long-term and survival-related outcomes highlight the need for further research. Finally, data on shunt diameter, post-procedure changes in HVPG, and stratified outcomes based on MELD score were unavailable in the included studies and thus could not be analyzed. This highlights the need for further research to address these critical gaps in understanding.

Conclusion

In conclusion, SPSS embolization is an effective treatment for patients with recurrent or refractory HE. Careful patient selection is important to balance long-term benefits with potential complications. Future randomized controlled trials are needed to compare its efficacy against standard medical management and to address technical factors and outcomes.

Footnotes

How to cite this article: Patel P, Ebrahim M, Zaher E, Khataniar H, Loganathan P, Adler DG. Embolization of spontaneous portosystemic shunts for refractory hepatic encephalopathy in cirrhosis patients: A meta-analysis. Hepatology Forum 2026; 7(2):91–100.

Conflict of Interest

The authors declare that they have nothing to disclose.

Financial Disclosure

The authors declare that they have no financial disclosures.

Use of AI for Writing Assistance

The authors affirm that no artificial intelligence (AI)–assisted technologies, including Large Language Models (LLMs), chatbots, or image generators, were used in the production of this work.

Author Contributions

Concept: PP, ME, EZ, HK, PL, DGA; Design: PP, ME, EZ, HK, PL, DGA; Supervision: PP, ME, EZ, HK, PL, DGA; Data Collection and/or Processing: PP, EZ, HK; Analysis and/or Interpretation: PP, ME, PL, DGA; Literature Review: PP, ME, EZ, HK; Writing: PP, ME, EZ, DGA; Critical Review: PP, ME, EZ, HK, PL, DGA.

Peer-review

Externally peer-reviewed.

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