Should prophylactic embolization of spontaneous portosystemic shunts be routinely performed during transjugular intrahepatic portosystemic shunt placement?

Non-variceal Extrahepatic Portosystemic Shunts: A Review of Pathogenesis, Diagnosis, and Treatment

Extrahepatic portosystemic shunts (EPS) are abnormal connections between the portal and systemic circulations. Acquired EPS occur most commonly in adults and are usually associated with portal hypertension due to cirrhosis. Acquired EPS cases can be further subdivided into two types: variceal (pre-existing) EPS and non-variceal EPS (NVEPS). Variceal EPS arise from originally small vessels with pre-existing dual portal and systemic drainage. Due to elevated portal pressure, these vessels dilate and undergo a reversal of flow, sending blood back to the systemic circulation. A much less common and, therefore, underappreciated subset of acquired EPS is NVEPS, which consists of aberrant connections that did not previously exist between the portal vein and large systemic vessels, usually in the presence of portal hypertension. Neoangiogenesis results in the development of abnormal anastomoses between the portal vein and other large veins, resulting in splenorenal, gastrorenal, portocaval, and mesocaval shunts. While not uncommon, they are frequently overlooked in the diagnosis and treatment of portal hypertension and can pose significant diagnostic and therapeutic challenges. Because the treatment of variceal EPS and NVEPS can differ markedly, it is important to correctly diagnose NVEPS and institute appropriate management. The aim of this article was to review acquired EPS, with particular attention to NVEPS, updating the pathogenesis, diagnosis, and treatment.

Management of hepatic encephalopathy following transjugular intrahepatic portosystemic shunts: Current strategies and future directions

Transjugular intrahepatic portosystemic shunts (TIPSs) are generally used for the management of complications of portal hypertension in patients with decompensated cirrhosis. However, hepatic encephalopathy (HE), which impairs neuropsychiatric function and motor control, remains the primary adverse effect of TIPS, limiting its utility. Prompt prevention and treatment of post-TIPS HE are critical, as they are strongly associated with readmission rates and poor quality of life. This review focuses on the main pathophysiological mechanisms underlying post-TIPS HE, explores advanced biomarkers and predictive tools, and discusses current management strategies and future directions to prevent or reverse HE following TIPS. These strategies include preoperative patient assessment, individualized shunt diameter optimization, spontaneous portosystemic shunt embolization during the TIPS procedure, postoperative preventive and therapeutic measures such as nutrition management, medical therapy, fecal microbiota transplantation, and stent reduction.

Persistent varices in cured patients: Understanding the role of hepatic venous pressure gradient

Background & Aims

Etiologic factor removal (ER) drives recompensation and improves portal hypertension in cirrhosis. Esophageal varices (EV) and portosystemic shunts (PSS) have been found in patients despite hepatic venous pressure gradient (HVPG) dropping below 10 mmHg after ER, questioning HVPG accuracy in reflecting true portal pressure in the setting of ER. We aim to evaluate the correlation of HVPG with direct portal pressure (DPP) in patients with persistence of EV after ER despite HVPG <10 mmHg.

Methods

This is a bicentric 'proof of concept' study evaluating HVPG and ultrasound-guided percutaneous DPP in patients with HCV or alcohol-related cirrhosis with persistent varices and HVPG <10 mmHg after at least 5 years of ER.

Results

Seven patients with HCV and three with alcohol-related cirrhosis with persistent varices and HVPG <10 mmHg after at least 5 years of ER were included. At evaluation, all patients had a patent portal vein and were compensated. The median platelet count was 129.5 (IQR 95-145) × 109/ml, and the median liver stiffness measurement was 16.15 (IQR 14.4-22.3) kPa. In five patients, EV remained the same size (two large and three small), and five downsized to small after ER. Wedge hepatic vein pressure (median 19 [IQR 16.5-20] mmHg) and portal pressure (median 18 [IQR 15-19.5] mmHg) had an excellent correlation (R = 0.93, p <0.0001). Portal pressure gradient (PPG) confirmed the absence of clinically significant portal hypertension as identified by HVPG across all the patients.

Conclusions

HVPG accurately reflects PPG in the context of HCV and alcohol-related cirrhosis regression. After ER, EV may persist despite HVPG <10 mmHg. The benefit of prophylaxis in patients with EV and HVPG <10 mmHg is unknown. Future studies with clinical endpoints are needed to validate our findings.

Impact and implications

Despite a favorable evolution after the removal of the etiologic factor, varices persist in some patients, and there is a lack of concise guidelines for the evaluation and management of portal hypertension in this population. Our research underscores the persistence of varices in the absence of clinically significant portal hypertension and significantly demonstrates the accuracy of hepatic venous pressure gradient (HVPG) in reflecting portal vein pressure in this specific patient group. These findings emphasize the crucial role of HVPG in the assessment of portal hypertension after etiologic factor removal and lay the groundwork for further investigation into clinical outcomes and the necessity of non-selective beta-blockers in individuals with persistent varices after the removal of etiologic factor.

Concurrent spontaneous portosystemic shunt embolization for the prevention of overt hepatic encephalopathy after TIPS: A systematic review and meta-analysis

BACKGROUND

Overt hepatic encephalopathy remains a serious complication after TIPS. Concomitant SPSS is associated with an increased risk of HE in patients treated with TIPS.

PURPOSE

To perform a systematic review and meta-analysis on the effectiveness and safety of the prophylactic embolization of SPSS at the time of TIPS creation.

MATERIALS AND METHODS

The PubMed, Embase, Cochrane Library, and Web of Science databases were searched up to April 2023 to identify studies on the association between antegrade embolized SPSS before TIPS placement and the incidence of post-TIPS HE. Odds ratios (ORs) and their corresponding 95% CIs were used to identify significant differences in the outcomes.

RESULTS

Four studies enrolling 1243 patients with cirrhosis who received TIPS for variceal bleeding were included. A meta-analysis revealed that TIPS without simultaneous SPSS embolization was associated with an increased risk of overt HE (OR 2.41, 95% CI 1.32-4.38; p = 0.004). The risks of mortality (0.79, 95% CI 0.58-1.07; p = 0.13), variceal rebleeding (0.94, 95% CI 0.66-1.34; p = 0.74) and shunt dysfunction (1.40, 95% CI 0.51-3.83; p = 0.51) did not significantly differ among the groups.

CONCLUSION

SPSS prevalence was associated with an increased risk of overt HE after TIPS. Concurrent antegrade SPSS embolization during TIPS creation reduced the risk for overt HE without increasing other complications.

Evolution of spontaneous portosystemic shunts over time and following aetiological intervention in patients with cirrhosis

BACKGROUND & AIMS

Spontaneous portosystemic shunts (SPSS) develop frequently in cirrhosis. Changes over time and the effect of aetiological interventions on SPSS are unknown, so we aimed to explore the effect of these variables on SPSS evolution.

METHODS

Patients with cirrhosis from the Baveno VI-SPSS cohort were selected provided a follow-up abdominal CT or MRI scan was available. Clinical and laboratory data were collected at baseline and follow-up. Imaging tests were reviewed to evaluate changes in the presence and size of SPSS (large (L)-SPSS was ≥8 mm) over time. Regarding alcohol- or HCV-related cirrhosis, two populations were defined: cured patients (abstinent from alcohol or successful HCV therapy), and non-cured patients.

RESULTS

A total of 617 patients were included. At baseline SPSS distribution was 22% L-SPSS, 30% small (S)-SPSS, and 48% without (W)-SPSS. During follow-up (median follow-up of 63 months), SPSS distribution worsened: L-SPSS 26%, S-SPSS 32%, and W-SPSS 42% (p <0.001). Patients with worse liver function during follow-up showed a simultaneous aggravation in SPSS distribution. Non-cured patients (n = 191) experienced a significant worsening in liver function, more episodes of liver decompensation and lower transplant-free survival compared to cured patients (n = 191). However, no differences were observed regarding SPSS distribution at inclusion and at follow-up, with both groups showing a trend to worsening. Total shunt diameter increased more in non-cured (52%) than in cured patients (28%). However, total shunt area (TSA) significantly increased only in non-cured patients (74 to 122 mm2, p <0.001).

CONCLUSIONS

The presence of SPSS in cirrhosis increases over time and parallels liver function deterioration. Aetiological intervention in these patients reduces liver-related complications, but SPSS persist although progression is decreased.

IMPACT AND IMPLICATIONS

There is no information regarding the evolution of spontaneous portosystemic shunts (SPSS) during the course of cirrhosis, and especially after disease regression with aetiological interventions, such as HCV treatment with direct-acting antivirals or alcohol abstinence. These results are relevant for clinicians dealing with patients with cirrhosis and portal hypertension because they have important implications for the management of cirrhosis with SPSS after disease regression. From a practical point of view, physicians should be aware that in advanced cirrhosis with portal hypertension, after aetiological intervention, SPSS mostly persist despite liver function improvement, and complications related to SPSS may still develop.

Friend or Foe? Spontaneous Portosystemic Shunts in Cirrhosis-Current Understanding and Future Prospects

Portal hypertension (PHT) in cirrhosis results from increased resistance to splanchnic blood flow secondary to parenchymal and vascular changes within the liver. In an attempt to counteract the increased portal pressure, two mechanisms simultaneously occur: splanchnic vasodilatation and formation of spontaneous portosystemic shunts (SPSS). Long considered to be a compensatory mechanism to decompress the portal venous system, it is now well established that SPSS are not only inefficient in decreasing the portal pressure but also contribute to reduced hepatocyte perfusion and increased splanchnic blood flow and resistance, associated with worsening PHT. Recent studies have described a high prevalence of SPSS in cirrhosis patients, increasing with liver dysfunction, and observed an association between the presence of SPSS and worse clinical outcomes. In cirrhosis patients with preserved liver functions, the presence of SPSS independently increases the risk of hepatic encephalopathy, variceal bleeding, and ascites, and reduces transplant-free survival. Moreover, the presence of SPSS in patients undergoing transjugular intrahepatic portosystemic shunting and liver transplant has been shown to variably affect the postprocedural outcome. This article provides an overview of the current understanding of the role of SPSS in the natural history of liver cirrhosis and their status as a therapeutic target and an imaging biomarker to identify patients at higher risk of developing complications of PHT.

Spontaneous portosystemic shunts in liver cirrhosis: new approaches to an old problem

Portal hypertension is the main consequence of liver cirrhosis, leading to severe complications such as variceal hemorrhage, ascites or hepatic encephalopathy. As an attempt to decompress the portal venous system, portal flow is derived into the systemic venous system through spontaneous portosystemic shunts (SPSSs), bypassing the liver. In this review, we aim to provide an overview of the published reports in relation to the prevalence and physiopathology behind the appearance of SPSS in liver cirrhosis, as well as the complications derived from its formation and its management. The role of SPSS embolization is specifically discussed, as SPSSs have been assessed as a therapeutic target, mainly for patients with recurrent/persistent hepatic encephalopathy and preserved liver function. Furthermore, different aspects of the role of SPSS in liver transplantation, as well as in candidates for transjugular intrahepatic portosystemic shunt are reviewed. In these settings, SPSS occlusion has been proposed to minimize possible deleterious effects, but results are so far inconclusive.

Comparison of transjugular intrahepatic portosystemic shunt for treatment of variceal bleeding in patients with cirrhosis with or without spontaneous portosystemic shunt

BACKGROUND AND AIMS

Transjugular intrahepatic portosystemic shunt (TIPS) is an effective intervention for portal hypertensive complications in cirrhosis. Spontaneous portosystemic shunts (SPSSs) may increase the risk of post-TIPS complications and mortality. This study was done to evaluate the safety and efficacy of TIPS for treating variceal bleeding between patients with and without SPSSs.

PATIENTS AND METHODS

The clinical data of 467 consecutive patients with cirrhosis who received TIPS for variceal bleeding from January 2012 to January 2018 were screened. A total of 33 patients with coexisting SPSSs were included as the SPSS group, and 33 patients without SPSSs were randomly selected as control. The procedure-related complications and long-term outcomes were compared between the two groups.

RESULTS

Both groups were successfully treated with TIPS. SPSSs were antegradely embolized before TIPS placement. In terms of safety, one patient in the SPSS group experienced an asymptomatic pulmonary embolism, and another patient experienced serious gastric ulcer bleeding. Overall, 23 (70.0%) patients in the SPSS group and 16 (51.5%) patients in the control group experienced different mild complications (P=0.131). During a median follow-up of more than 2 years, the rebleeding rates (7.1 vs. 3.7% at 1 year, P=0.508), overt hepatic encephalopathy occurrence rates (34.4 vs. 39.4% at 2 years, P=0.685), and orthotopic liver transplantation-free survival rates (73.2 vs. 70.7% at 2 years, P=0.557) were not significantly different between the two groups.

CONCLUSION

TIPS combined with antegrade embolization is safe, effective, and feasible for patients with SPSSs, with safety and long-term outcomes comparable to patients without SPSSs.