The portal hypertension syndrome: etiology, classification, relevance, and animal models

Identifying the optimal measurement timing and hemodynamic targets of portal pressure gradient after TIPS in patients with cirrhosis and variceal bleeding

BACKGROUND & AIMS

The optimal timing of measurement and hemodynamic targets of portacaval pressure gradient (PPG) after transjugular intrahepatic portosystemic shunt (TIPS) placement remain unclear. This study aimed to identify the ideal moment for hemodynamic measurements and the optimal target of PPG in patients undergoing covered TIPS for variceal bleeding.

METHODS

Between May 2018 and December 2021, 466 consecutive patients with recurrent variceal bleeding treated with covered TIPS were prospectively included. Post-TIPS PPG was measured immediately (immediate PPG), 24-72 hours (early PPG), and again 1 month (late PPG) after TIPS placement. The agreement among PPGs measured at different time points was assessed by intra-class correlation coefficient (ICC) and Bland-Altman method. The unadjusted and confounder-adjusted effects of PPGs on clinical outcomes (portal hypertensive complications [PHCs], overt hepatic encephalopathy [OHE], further decompensation, and death) were assessed using Fine and Gray competing risk regression models.

RESULTS

The agreement between early PPG and late PPG (ICC: 0.34) was better than that between immediate PPG and late PPG (ICC: 0.23, p <0.001). Early PPG revealed an excellent predictive value for PHCs (early PPG≥ vs. <12 mmHg: adjusted hazard ratio 2.17, 95% CI 1.33-3.55, p = 0.002) and OHE (0.40, 95% CI 0.17-0.91, p = 0.030), while immediate PPG did not. Late PPG showed a predictive value for PHC risk but not OHE. By targeting the lowest risk of further decompensation, we identified an optimal hemodynamic target with early PPG ranging from 11 to 14 mmHg that was associated with a decreased risk of OHE and effective prevention of PHCs.

CONCLUSIONS

PPG measured 24 to 72 hours after TIPS correlates with long-term PPG and clinical outcomes, and a hemodynamic target PPG of 11-14 mmHg is associated with reduced encephalopathy but not compromised clinical efficacy.

IMPACT AND IMPLICATIONS

The optimal timing of measurement and hemodynamic targets of portacaval pressure gradient (PPG) after transjugular intrahepatic portosystemic shunt (TIPS) remain unclear. Here we show that post-TIPS PPG measured at least 24 hours but not immediately after the procedure correlated with long-term PPG and clinical events. Thus, PPG measurements taken at least 24 hours after TIPS should be used to guide decision making in order to improve clinical outcomes. Targeting a post-TIPS PPG of 11-14 mmHg or a 20%-50% relative reduction from pre-TIPS baseline measured 24-72 hours after the procedure was associated with reduced encephalopathy but not compromised clinical efficacy. Thus, these criteria could be used to guide TIPS creation and revision in patients with cirrhosis and variceal bleeding undergoing covered TIPS.

CLINICAL TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, ID: NCT03590288.

Preoperative serum total bilirubin-albumin ratio as a prognostic indicator in patients with hepatitis-related cirrhosis after splenectomy

BACKGROUND

Splenectomy is an effective yet invasive intervention for alleviating portal pressure in patients with hepatitis cirrhosis. However, the current prognostic indicators for predicting long-term overall survival of these patients have several limitations.

AIM

To assess the potential of preoperative total bilirubin-albumin (B/A) ratio as a prognostic indicator for patients with hepatitis cirrhosis undergoing splenectomy.

METHODS

A total of 257 patients diagnosed with hepatitis cirrhosis were retrospectively enrolled in the study. Normality test, t-test, Wilcoxon test, χ² test, or Fisher’s exact test was employed to analyze the intraoperative and postoperative conditions of the patients. Receiver operating characteristic (ROC) curve analysis was utilized to depict the 10-year overall survival rate.

RESULTS

During the follow-up period, 85.99% of the patients survived, with a median survival time of 64.6 months. Multivariate analysis revealed that total serum B/A ratio was an independent risk factor for overall survival (P = 0.037). ROC curve analysis demonstrated that a B/A ratio of 0.87 was the optimal cut-off value. Consequently, the patients were categorized into two groups: High B/A group (n = 64) and low B/A group (n = 193). The median follow-up time for the high B/A group and low B/A group was 56.8 months and 67.2 months, respectively (P = 0.045). Notably, the high B/A group exhibited a significantly lower 10-year overall survival compared to the low B/A group (P < 0.001). Patients with hepatocellular carcinoma (HCC) had lower overall survival rates. Patients with a high B/A ratio exhibited a lower overall survival than those with a low B/A rate in the overall cohort and the subgroups of patients with HCC or not, early Child-Pugh grade, low albumin-bilirubin grade, and model for end-stage liver disease score ≥ 10 (log-rank test, P < 0.001 for all).

CONCLUSION

The B/A ratio can serve as an effective prognostic indicator for overall survival in patients with hepatitis B virus-related cirrhosis following splenectomy, and a higher B/A ratio may suggest a poorer prognosis.

Role of Virtual Ruler-Based Diameter Measurement in Endoscopic Therapy for Cirrhotic Esophageal Varices: A Retrospective Multicenter Study

Background: Esophageal variceal (EV) diameter is a critical, independent risk factor for hemorrhage, and plays a key role in guiding choices of endoscopic treatment techniques. We developed a novel tool, the virtual ruler (VR), which offers increased precision and expediency in EV diameter (EVD) measurements. This study investigates the clinical value of VR for assessing EVD during the endoscopic treatment of cirrhotic EVs. Methods: We performed a retrospective multicenter review of 345 cirrhotic patients with EVs who received endoscopic treatment. EVD was measured using VR, and several outcomes, including rebleeding rates, vascular eradication rates, mortality, and complication incidences, were compared in patients stratified by EVD as measured by both VR and endoscopists. Results: There was moderate agreement between VR and endoscopist measurements of EVD (Kappa = 0.591, p < 0.001). In patients with EVD > 1 cm, the VR group had a lower rebleeding rate after endoscopic treatment compared to the endoscopist group (3.8% vs. 11.3%; p=0.048). No significant between-group differences in outcomes were noted in patients with EVD ≤ 1 cm. Additionally, comparisons of endoscopic variceal ligation and endoscopic injection sclerotherapy within the VR-based diameter groups showed no substantial differences in treatment efficacy or adverse events (p > 0.05). Conclusion: Using VR to accurately measure EVD may help decrease endoscopist misjudgment of larger EVD values and may reduce postoperative rebleeding rates after endoscopic treatment. VR holds potential clinical significance in guiding endoscopic EV treatment. Trial Registration: Clinical Trial Registry identifier: ChiCTR2200064028.

The Balloon Catheter Method and the End-hole Catheter Method in the Measurement of Hepatic Venous Pressure Gradient: a Comparative Study

OBJECTIVE

This study aims to evaluate the differences between The balloon catheter method and End-hole Catheter Method in measuring hepatic venous pressure gradient (HVPG) among cirrhosis patients.

METHODS

From October 2017 to January 2024, patients who underwent HVPG measurements using both methods were consecutively included. HVPGs obtained from both methods were compared with the portal vein pressure gradient (PPG) obtained via transjugular intrahepatic portosystemic shunt (TIPS) using paired comparisons. Additionally, the consistency and predictive ability for bleeding risk of the two methods, as well as the impact of intrahepatic veno-venous shunt (IHVS), were analyzed.

RESULTS

The study enrolled 145 patients, each of whom had HVPG measured by both methods. PPG was measured in 61 patients. There was a statistically significant difference between the PPGs and HVPGs measured by both the balloon catheter method and the end-hole catheter method (P < 0.001), with the HVPG mean values obtained by the end-hole catheter method being closer to the PPGs. In the non-IHVS group, no significant statistical difference was found between the two methods (P = 0.071). In contrast, the IHVS group showed a significant difference (P < 0.001), with a mean difference of 2.98 ± 4.03 mmHg. When IHVS was absent, the measurement results from the end-hole catheter method and the balloon catheter method were found to be highly correlated. The end-hole catheter method has a higher screening capability for patients at risk of bleeding compared to the balloon catheter method (75.90% vs. 72.86%).

CONCLUSION

HVPG measurements using either the balloon catheter method or end-hole catheter method showed significant difference with the PPG. The end-hole catheter method has a higher screening capability for patients at risk of bleeding, and IHVS could lead to lower HVPG measurements with The balloon catheter method.

Application of liver biopsy in etiological diagnosis of unexplained portal hypertension: Porto-sinusoidal vascular disease should not be ignored

The diagnostic value of liver biopsy has been confirmed in patients with abnormal liver test results; however, little data are available on its application in patients with portal hypertension. This study aimed to investigate the utility of liver biopsy for the etiological diagnosis of unexplained portal hypertension, and explore the clinical and pathological characteristics of each etiology. A retrospective observational analysis was conducted on 1367 patients who underwent liver biopsy at the Second Hospital of Nanjing from 2017 to 2019. Of these, 188 patients with unexplained portal hypertension were enrolled. The clinical and pathological characteristics were collected and reassessed in a multidisciplinary team meeting. Among these patients, 174 (92.6%, 174/188) had a definite etiological diagnosis through liver biopsy. The main etiologies were autoimmune hepatitis in 47 patients (25%, 47/188), autoimmune hepatitis-primary biliary cirrhosis overlap syndrome in 41 patients (21.8%, 41/188), and porto-sinusoidal vascular disease (PSVD) in 40 patients (21.3%, 40/188). Compared to liver cirrhosis, PSVD patients were younger and the liver function damage of which was subtler. The widths of portal vein diameter were widest in PSVD but the liver stiffness measurement were almost normal. Splenomegaly was common in PSVD, but ascites were less frequent than in autoimmune hepatitis (25.0% vs 51.1%, P = .013). Based on the histological patterns, we found that cholestatic liver diseases such as primary biliary cirrhosis, autoimmune hepatitis-primary biliary cirrhosis overlap syndrome, and progressive familial intrahepatic cholestasis could lead to non-cirrhotic portal hypertension, while vascular liver diseases such as PSVD and Budd-Chiari syndrome could also show fibrous proliferation as the disease progresses. Liver biopsy is safe and valuable for etiological diagnosis of unexplained portal hypertension. Cirrhosis is the leading cause of portal hypertension, and porto-sinusoidal vascular diseases should also be considered. Clinical features may be helpful in suggesting the cause; however, pathological examination is still indispensable for disease diagnosis and progression assessment.

Therapeutic potential of rifaximin in liver diseases

Rifaximin, derived from rifamycin, is a broad-spectrum antibiotic by inhibiting bacterial RNA synthesis. Rifaximin has a very low intestinal absorption and exerts its antimicrobial activity primarily in the intestinal tract. It regulates the gut microbiota with limited side effects systemically. Rifaximin has been recommended for the treatment of hepatic encephalopathy but some studies shed light on its medicinal effects in many other diseases. For instance, rifaximin may suppress the progression of liver fibrosis and its related complications, and ameliorate metabolic dysfunction-associated steatotic liver disease and alcohol-associated liver disease, etc. Rifaximin can also mediate anti-inflammation, antiproliferation, and proapoptotic events by activating pregnane X receptor, which is efficious in cancers such as colon cancer. In addition, some investigations have shown rifaximin may play a therapeutic role in various autoimmune and neurological disorders. However, these findings still need more real-world practices and in-depth investigations to obtain more precise indications and fully elucidate the multifaceted potentials of rifaximin.

GSDMD-Dependent Neutrophil Extracellular Traps Mediate Portal Vein Thrombosis and Associated Fibrosis in Cirrhosis

Portal vein thrombosis (PVT) is a challenging and controversial complication of cirrhosis. Experimental models that reproduce cirrhotic PVT and effective pharmacological therapies are limited. We aimed to investigate the nature course and mechanisms of PVT in cirrhosis. A novel PVT model was developed via two-step total portal vein ligation in healthy and thioacetamide (TAA)-cirrhotic rats. Circulating and liver-infiltrating neutrophils were isolated from individuals with cirrhosis to examine neutrophil extracellular traps (NETs) and explore their unique characteristics and implications in PVT-associated fibrosis in cirrhosis. We further validated macrophage-myofibroblast transition (MMT) via multiplex immunofluorescence and single-cell sequencing. In the experimental model, cirrhosis promoted PVT development and portal vein intimal thickening. Interestingly, cirrhosis promoted spontaneous resolution of PVT due to instability of thrombus structure, along with pulmonary and intrahepatic clots. NETs-MMT mediate cirrhotic PVT and PVT-associated fibrosis, including fibrotic thrombus remodeling and increased hepatic collagen deposition. Mechanistically, caspase-4-dependent activation of neutrophils and GSDMD mediated the formation of NETs. The extracellular DNA of NETs promoted TGF-β1/Smad3-driven MMT. Inhibiting GSDMD with disulfiram suppressed cirrhotic PVT and prevented associated fibrosis. The cirrhotic PVT model reflected the following three main characteristics of cirrhotic PVT: spontaneous resolution, immunothrombosis, and intimal fibrosis. Targeting NETs with GSDMD inhibitors may serve as a new therapeutic concept to treat cirrhotic PVT.

Sclerosing mesenteritis as a cause of porto-mesenteric vascular obstruction

A woman in her 20s presented with haematemesis, post-prandial abdominal pain, weight loss and anaemia. Imaging revealed a non-enhancing mass in the retroperitoneal space along the mesenteric plane, encasing the porto-mesenteric vasculature. Endoscopy showed oesophageal varices. She was diagnosed with sclerosing mesenteritis, causing extrinsic compression of the portal vein and superior mesenteric artery. She underwent endoscopic variceal ligation and received prednisolone and tamoxifen. After 3 months, her post-prandial pain improved, and she did not have further bleeding episodes.

Infectious Complications of Portal Hypertension

Patients with cirrhosis and clinically significant portal hypertension are at high risk of developing bacterial infections (BIs) that are the most common trigger of acute decompensation and acute-on-chronic liver failure. Furthermore, after decompensation, the risk of developing BIs further increases in an ominous vicious circle. BIs may be subtle, and they should be ruled out in all patients at admission and in case of deterioration. Timely administration of adequate empirical antibiotics is the cornerstone of treatment. Herein, we reviewed current evidences about pathogenesis, clinical implications and management of BIs in patients with cirrhosis and portal hypertension.

Hepatic Veno-Occlusive Disease and Colorectal Cancer: Expect the Unexpected

Sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) is a rare liver vascular condition, potentially life-threatening, with clinical signs of portal hypertension, frequently reported in relation to bone marrow transplantation and possibly in non-transplantation-related chemotherapy. We report the case of a 65-year-old female patient who insidiously developed fatigue, mild tenderness of the right upper abdominal quadrant, hepato-splenomegaly and slight weight gain consecutive to ascites development, as well as persistent elevation of transaminases and mild thrombocytopenia. To note, she had a previous history of colorectal cancer (CRC) with liver metastases and several courses of chemotherapy. Abdominal duplex and elastography measurements made the diagnosis of cirrhosis improbable. A lot of lab work-ups were performed in order to rule out several diseases and conditions. Further, transjugular access was used to perform the measurement of the hepatic venous pressure gradient and liver biopsy that confirmed SOS/VOD. In late 2023, she was diagnosed with endometrial adenocarcinoma, requiring chemotherapy again. At present, the liver condition is stationary, but the prognosis is, however, uncertain. In conclusion, we presented the atypical case of a female patient who developed portal hypertension syndrome associated with the late onset of SOS/VOD, after 5-fluorouracil and oxaliplatin chemotherapy for CRC and liver metastases, subsequently diagnosed with endometrial adenocarcinoma, which posed many diagnostic and therapeutic challenges. Given the potentially bad outcome, an early diagnosis of SOS/VOD in patients receiving drugs of risk is important not only to stratify further risk, but also to initiate an appropriate therapy in order to improve the prognosis.

Obliteration of portal venules contributes to portal hypertension in biliary cirrhosis

The effects of the obliteration of portal venules (OPV) in cirrhotic portal hypertension are poorly understood. To investigate its contribution to portal hypertension in biliary cirrhosis and its underlying mechanism, we evaluated OPV using two-dimensional (2D) histopathology in liver explants from patients with biliary atresia (BA, n = 63), primary biliary cholangitis (PBC, n = 18), and hepatitis B-related cirrhosis (Hep-B-cirrhosis, n = 35). Then, three-dimensional (3D) OPV was measured by X-ray phase-contrast CT in two parallel models in rats following bile duct ligation (BDL) or carbon tetrachloride (CCl4) administration, representing biliary cirrhosis and post-necrotic cirrhosis, respectively. The portal pressure was also measured in the two models. Finally, the effects of proliferative bile ducts on OPV were investigated. We found that OPV was significantly more frequent in patients with biliary cirrhosis, including BA (78.57 ± 16.45%) and PBC (60.00 ± 17.15%), than that in Hep-B-cirrhotic patients (29.43 ± 14.94%, p < 0.001). OPV occurred earlier, evidenced by the paired liver biopsy at a Kasai procedure (KP), and was irreversible even after a successful KP in the patients with BA. OPV was also significantly more frequent in the BDL models than in the CCl4 models, as shown by 2D and 3D quantitative analysis. Portal pressure was significantly higher in the BDL model than that in the CCl4 model. With the proliferation of bile ducts, portal venules were compressed and irreversibly occluded, contributing to the earlier and higher portal pressure in biliary cirrhosis. OPV, as a pre-sinusoidal component, plays a key role in the pathogenesis of portal hypertension in biliary cirrhosis. The proliferated bile ducts and ductules gradually take up the 'territory' originally attributed to portal venules and compress the portal venules, which may lead to OPV in biliary cirrhosis. © 2024 The Pathological Society of Great Britain and Ireland.

Role of Endoscopy in the Diagnosis, Grading, and Treatment of Portal Hypertensive Gastropathy and Gastric Antral Vascular Ectasia

Portal hypertensive gastropathy (PHG) and gastric antral vascular ectasia (GAVE) are 2 distinct gastric vascular abnormalities that may present with acute or chronic blood loss. PHG requires the presence of portal hypertension and is typically associated with chronic liver disease, whereas there is controversy about the association of GAVE with chronic liver disease and/or portal hypertension. Distinguishing between GAVE and PHG is crucial because their treatment strategies differ. This review highlights characteristic endoscopic appearances and the clinical features of PHG and GAVE, which, in turn, aid in their appropriate management.

The polymorphic variant of SerpinB3 (SerpinB3-PD) is associated with faster cirrhosis decompensation

BACKGROUND

SerpinB3 is a cysteine protease inhibitor involved in liver disease progression due to its proinflammatory and profibrogenic properties. The polymorphic variant SerpinB3-PD (SB3-PD), presents a substitution in its reactive centre loop, determining the gain of function.

AIMS

To disclose the clinical characteristics of a cohort of patients with cirrhosis in relation to the presence of SB3-PD and to assess the effect of this genetic variant on fibrogenic and inflammatory cytokines in vitro.

METHODS

We assessed SB3 polymorphism in 90 patients with cirrhosis, prospectively followed up in our referral centre. We used HepG2 and HuH-7 cells transfected to overexpress either wild-type SB3 (SB3-WT) or SB3-PD to assess their endogenous effect, while LX2 and THP-1 cells were treated with exogenous SB3-WT or SB3-PD proteins.

RESULTS

Patients carrying SB3-PD had more severe portal hypertension and higher MELD scores, than patients carrying SB3-WT. In multivariate analysis, SB3-PD was an independent predictor of cirrhosis complications. Patients with SB3-PD polymorphism presented with more severe liver fibrosis and inflammatory features. Hepatoma cells overexpressing SB3-PD showed higher TGF-β1 expression than controls. The addition of recombinant SB3-PD induced an up-regulation of TGF-β1 in LX2 cells and a more prominent inflammatory profile in THP-1 cells, compared to the effect of SB3-WT protein.

CONCLUSIONS

The polymorphic variant SB3-PD is highly effective in determining activation of TGF-β1 and inflammation in vitro. Patients with cirrhosis who carry SB3-PD polymorphism may be more prone to develop severe liver disease progression. However, further validation studies are warranted to support the in vivo relevance of this polymorphism.

Recent advances in promising drugs for primary prevention of gastroesophageal variceal bleeding with cirrhotic portal hypertension

BACKGROUND

Gastroesophageal variceal bleeding is one of the most severe complications of patients with cirrhosis. Although primary prevention drugs, including non-selective β-blockers, have effectively reduced the incidence of bleeding, their efficacy is limited due to side effects and related contraindications. With recent advances in precision medicine, precise drug treatment provides better treatment efficacy.

DATA SOURCES

Literature search was conducted in PubMed, MEDLINE and Web of Science for relevant articles published up to May 2022. Information on clinical trials was obtained from https://clinicaltrials.gov/ and http://www.chictr.org.cn/.

RESULTS

The in-depth understanding of the pathogenesis and advances of portal hypertension has enabled the discovery of multiple molecular targets for promising drugs. According to the site of action, these drugs could be classified into four classes: intrahepatic, extrahepatic, both intrahepatic and extrahepatic targets and others. All these classes of drugs offer advantages over traditional treatments in prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.

CONCLUSIONS

This review classified and summarized the promising drugs, which prevent gastroesophageal variceal bleeding by targeting specific markers of pathogenesis of portal hypertension, demonstrating the significance of using the precision medicine strategy to discover and develop promising drugs for the primary prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.

Portal hypertension in patients with nonalcoholic fatty liver disease: Current knowledge and challenges

Portal hypertension (PH) has traditionally been observed as a consequence of significant fibrosis and cirrhosis in advanced non-alcoholic fatty liver disease (NAFLD). However, recent studies have provided evidence that PH may develop in earlier stages of NAFLD, suggesting that there are additional pathogenetic mechanisms at work in addition to liver fibrosis. The early development of PH in NAFLD is associated with hepatocellular lipid accumulation and ballooning, leading to the compression of liver sinusoids. External compression and intra-luminal obstacles cause mechanical forces such as strain, shear stress and elevated hydrostatic pressure that in turn activate mechanotransduction pathways, resulting in endothelial dysfunction and the development of fibrosis. The spatial distribution of histological and functional changes in the periportal and perisinusoidal areas of the liver lobule are considered responsible for the pre-sinusoidal component of PH in patients with NAFLD. Thus, current diagnostic methods such as hepatic venous pressure gradient (HVPG) measurement tend to underestimate portal pressure (PP) in NAFLD patients, who might decompensate below the HVPG threshold of 10 mmHg, which is traditionally considered the most relevant indicator of clinically significant portal hypertension (CSPH). This creates further challenges in finding a reliable diagnostic method to stratify the prognostic risk in this population of patients. In theory, the measurement of the portal pressure gradient guided by endoscopic ultrasound might overcome the limitations of HVPG measurement by avoiding the influence of the pre-sinusoidal component, but more investigations are needed to test its clinical utility for this indication. Liver and spleen stiffness measurement in combination with platelet count is currently the best-validated non-invasive approach for diagnosing CSPH and varices needing treatment. Lifestyle change remains the cornerstone of the treatment of PH in NAFLD, together with correcting the components of metabolic syndrome, using nonselective beta blockers, whereas emerging candidate drugs require more robust confirmation from clinical trials.

How non-alcoholic fatty liver disease and cirrhosis affect the heart

Liver diseases affect the heart and the vascular system. Cardiovascular complications appear to be a leading cause of death in patients with non-alcoholic fatty liver disease (NAFLD) and cirrhosis. The predominant histological changes in the liver range from steatosis to fibrosis to cirrhosis, which can each affect the cardiovascular system differently. Patients with cirrhotic cardiomyopathy (CCM) and NAFLD are at increased risk of impaired systolic and diastolic dysfunction and for suffering major cardiovascular events. However, the pathophysiological mechanisms behind these risks differ depending on the nature of the liver disease. Accurate assessment of symptoms by contemporary diagnostic modalities is essential for identifying patients at risk, for evaluating candidates for treatment, and prior to any invasive procedures. This review explores current perspectives within this field.

Mechanical stress induced EndoMT in endothelial cells through PPARγ downregulation

Portal hypertension is a group of clinical syndromes induced by increased portal system pressure due to various etiologies including cirrhosis. When portal hypertension develops, the portal vein dilates and endothelial cells (ECs) in the portal vein are subjected to mechanical stretch. In this study, elastic silicone chambers were used to simulate the effects of mechanical stretch on ECs under portal hypertension. We found that mechanical stretch decreased PPARγ expression in ECs by blocking the PI3K/AKT/CREB signaling pathway or increasing NEDD4-mediated ubiquitination and degradation of PPARγ. Moreover, PPARγ downregulation triggered Endothelial-to-mesenchymal transition (EndoMT) in ECs under stretch by promoting Smad3 phosphorylation. The PPARγ agonist rosiglitazone mitigated stretch-induced EndoMT in vitro and alleviated EndoMT of the portal vein endothelium in cirrhotic rats.

Evolving Understanding of Noncirrhotic Portal Hypertension

Although cirrhosis is one of the most common causes of portal hypertension, noncirrhotic portal hypertension can result from hemodynamic perturbations occurring in the prehepatic, intrahepatic, and posthepatic circulation. Intrahepatic portal hypertension can be further subclassified relative to the hepatic sinusoids as presinusoidal, sinusoidal, and postsinusoidal. For many of these differential diagnoses, the etiology is known but the cause of idiopathic noncirrhotic portal hypertension, recently included in porto-sinusoidal vascular disease (PSVD), remains poorly understood. Herein, we discuss the diagnostic pathological features of noncirrhotic portal hypertension, with an emphasis on PSVD.

Close Relationship between Systemic Arterial and Portal Venous Pressure in an Animal Model with Healthy Liver

It is unclear to what extent systemic arterial blood pressure influences portal pressure. This relationship is clinically important as drugs, which are conventionally used for therapy of portal hypertension, may also influence systemic arterial blood pressure. This study investigated the potential correlation between mean arterial (MAP) and portal venous pressure (PVP) in rats with healthy livers. In a rat model with healthy livers, we investigated the effect of manipulation of MAP on PVP. Interventions consisted of 0.9% NaCl (group 1), 0.1 mg/kg body weight (bw) Sildenafil (low dose), an inhibitor of phosphodiesterase-5 (group 2), and 1.0 mg/kg bw Sildenafil (high dose, group 3) in 600 µL saline injected intravenously. Norepinephrine was used to increase MAP in animals with circulatory failure while PVP was monitored. Injection of the fluids induced a transient drop in MAP and PVP, probably due to a reversible cardiac decompensation. The drop in MAP and drop in PVP are significantly correlated. The time lag between change in MAP and change in PVP by 24 s in all groups suggests a cause-and-effect relationship. Ten minutes after the injection of the fluid, cardiac function was normalized. Thereafter, MAP gradually decreased. In the NaCl group, PVP decreases by 0.485% for a 1% drop of MAP, by 0.550% in the low-dose sildenafil group, and by 0.651% in the high-dose sildenafil group (p < 0.05 for difference group two vs. group one, group three vs. group one, and group three vs. group two). These data suggest that Sildenafil has an inherent effect on portal pressure that exceeds the effect of MAP. Injection of norepinephrine led to a sudden increase in MAP followed by an increase in PVP after a time lag. These data show a close relationship between portal venous pressure and systemic arterial pressure in this animal model with healthy livers. A change in MAP is consequently followed by a change in PVP after a distinct time lag. This study, furthermore, suggests that Sildenafil influences portal pressure. Further studies should be performed in a model with cirrhotic livers, as these may be important in the evaluation of vasoactive drugs (e.g., PDE-5-inhibitors) for therapy of portal hypertension.

Increased sinusoidal pressure impairs liver endothelial mechanosensing, uncovering novel biomarkers of portal hypertension

Background & Aims

Portal hypertension (PH) is a frequent and severe clinical syndrome associated with chronic liver disease. Considering the mechanobiological effects of hydrostatic pressure and shear stress on endothelial cells, we hypothesised that PH might influence the phenotype of liver sinusoidal endothelial cells (LSECs) during disease progression. The aim of this study was to investigate the effects of increased hydrodynamic pressure on LSECs and to identify endothelial-derived biomarkers of PH.

Methods

Primary LSECs were cultured under normal or increased hydrodynamic pressure within a pathophysiological range (1 vs. 12 mmHg) using a microfluidic liver-on-a-chip device. RNA sequencing was used to identify pressure-sensitive genes, which were validated in liver biopsies from two independent cohorts of patients with chronic liver disease with PH (n = 73) and participants without PH (n = 23). Biomarker discovery was performed in two additional independent cohorts of 104 patients with PH and 18 patients without PH.

Results

Transcriptomic analysis revealed marked deleterious effect of pathological pressure in LSECs and identified chromobox 7 (CBX7) as a key transcription factor diminished by pressure. Hepatic CBX7 downregulation was validated in patients with PH and significantly correlated with hepatic venous pressure gradient. MicroRNA 181a-5p was identified as pressure-induced upstream regulator of CBX7. Two downstream targets inhibited by CBX7, namely, E-cadherin (ECAD) and serine protease inhibitor Kazal-type 1 (SPINK1), were found increased in the bloodstream of patients with PH and were highly predictive of PH and clinically significant PH.

Conclusions

We characterise the detrimental effects of increased hydrodynamic pressure on the sinusoidal endothelium, identify CBX7 as a pressure-sensitive transcription factor, and propose the combination of two of its reported products as biomarkers of PH.

Impact and Implications

Increased pressure in the portal venous system that typically occurs during chronic liver disease (called portal hypertension) is one of the main drivers of related clinical complications, which are linked to a higher risk of death. In this study, we found that pathological pressure has a harmful effect on liver sinusoidal endothelial cells and identified CBX7 as a key protein involved in this process. CBX7 regulates the expression of E-cadherin and SPINK1, and consequently, measuring these proteins in the blood of patients with chronic liver disease allows the prediction of portal hypertension and clinically significant portal hypertension.

Effects of hypersplenism on the outcome of hepatectomy in hepatocellular carcinoma with hepatitis B virus related portal hypertension

Background

Although hepatectomy plus splenectomy is not regularly recommended for hepatocellular carcinoma (HCC) with portal hypertension related hypersplenism due to the high risk accompanied with surgical procedures for now. Many researchers still believe that hypersplenism is a controversial adverse prognostic factor for HCC patients. Thus, the primary objective of the study was to determine the effects of hypersplenism on the prognosis of these patients during and after hepatectomy.

Methods

A total of 335 patients with HBV-related HCC who underwent surgical resection as primary intervention were included in this study and categorized into three groups. Group A consisted of 226 patients without hypersplenism, Group B included 77 patients with mild hypersplenism, and Group C contained 32 patients with severe hypersplenism. The influence of hypersplenism on the outcome during the perioperative and long-term follow-up periods was analyzed. The independent factors were identified using the Cox proportional hazards regression model.

Results

The presence of hypersplenism is associated with longer hospital stays, more postoperative blood transfusions, and higher complication rates. The overall survival (OS, P = 0.020) and disease-free survival (DFS, P = 0.005) were significantly decreased in Group B compared to those in Group A. Additionally, the OS (P = 0.014) and DFS (P = 0.005) were reduced in Group C compared to those in Group B. Severe hypersplenism was a significant independent prognostic variable for both OS and DFS.

Conclusion

Severe hypersplenism prolonged the hospital stay, increased the rate of postoperative blood transfusion, and elevated the incidence of complications. Furthermore, hypersplenism predicted lower overall and disease-free survivals.

Validation of 4D flow cardiovascular magnetic resonance in TIPS stent grafts using a 3D-printed flow phantom

BACKGROUND

Four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) is feasible for portal blood flow evaluation after placement of transjugular intrahepatic portosystemic shunts (TIPS) in patients with liver cirrhosis. However, clinical acceptance of 4D flow CMR in TIPS patients is limited due to the lack of validation studies. The purpose of this study was to validate 4D flow CMR-derived measurements in TIPS stent grafts using a three-dimensional (3D)-printed flow phantom.

METHODS

A translucent flow phantom of the portal vasculature was 3D-printed. The phantom consisted of the superior mesenteric vein and the splenic vein draining into the portal vein, the TIPS-tract, and the hepatic vein. A TIPS stent graft (Gore® Viatorr®) was positioned within the TIPS-tract. Superior mesenteric vein and splenic vein served as inlets for blood-mimicking fluid. 4D flow CMR acquisitions were performed at 3T at preset flow rates of 0.8 to 2.8 l/min using velocity encoding of both 1.0 and 2.0 m/s. Flow rates and velocities were measured at predefined levels in the portal vasculature and within the stent graft. Accuracy of 4D flow CMR was assessed through linear regression with reference measurements obtained by flow sensors and two-dimensional (2D) phase contrast (PC) CMR. Intra- and interobserver agreement were assessed through Bland-Altman analyses.

RESULTS

At a velocity encoding of 2.0 m/s, 4D flow CMR-derived flow rates and velocities showed an excellent correlation with preset flow rates and 2D PC CMR-derived flow velocities at all vascular levels and within the stent graft (all r ≥ 0.958, p ≤ 0.003). At a velocity encoding of 1.0 m/s, aliasing artifacts were present within the stent graft at flow rates ≥ 2.0 l/min. 4D flow CMR-derived measurements revealed high intra- and interobserver agreement.

CONCLUSIONS

The in vitro accuracy and precision of 4D flow CMR is unaffected by the presence of TIPS stent grafts, suggesting that 4D flow CMR may be used to monitor TIPS patency in patients with liver cirrhosis.

Expert consensus on emergency procedures for portal hypertension bleeding (2022)

Expert consensus proposes an emergency treatment protocol for portal hypertension bleeding. Herein, the emergency treatment procedures, which include first aid, medical, interventional, and surgical treatments, are described. In addition, the indications, contraindications, operating norms, precautions, and prevention of complications of portal hypertension are described to optimize the first aid process.

Improving Management of Portal Hypertension: The Potential Benefit of Non-Etiological Therapies in Cirrhosis

Portal hypertension is the consequence of cirrhosis and results from increased sinusoidal vascular resistance and hepatic blood inflow. Etiological therapies represent the first intervention to prevent a significant increase in portal pressure due to chronic liver damage. However, other superimposed pathophysiological drivers may worsen liver disease, including inflammation, bacterial translocation, endothelial dysfunction, and hyperactivation of hemostasis. These mechanisms can be targeted by a specific class of drugs already used in clinical practice. Albumin, rifaximin, statins, aspirin, and anticoagulants have been tested in cirrhosis and were a topic of discussion in the last Baveno consensus as non-etiological therapies. Based on the pathogenesis of portal hypertension in cirrhosis, our review summarizes the main mechanisms targeted by these drugs as well as the clinical evidence that considers them a valid complementary option to manage patients with cirrhosis and portal hypertension.

Transjugular intrahepatic portosystemic shunt for portal hypertension: 30 years experience from China

Liver diseases are a major cause of illness and death worldwide. In China, liver diseases, primarily viral hepatitis, affect approximately 300 million people, thus having a major impact on the global burden of liver diseases. Portal hypertension is the most severe complication of chronic liver diseases, including ascites, hepatic encephalopathy and bleeding from gastroesophageal varices. Transjugular intrahepatic portosystemic shunt (TIPS) represents a very effective treatment of these complications. Since its introduction 30 years ago in China, the use of TIPS has evolved and has played an increasingly important role in the management of the complications of portal hypertension. This review will focus on the history, current application and management of complications of TIPS in China.

Mechanotransduction in the pathogenesis of non-alcoholic fatty liver disease

Mechanobiology is a domain of interdisciplinary research that aims to explore the impact of physical force, applied externally or internally, on cell and tissue function, including development, growth, and differentiation. Mechanotransduction is a term that describes how cells sense physical forces (such as compression, stretch, and shear stress), convert them into biochemical signals, and mount adaptive responses integrated by the nucleus. There is accumulating evidence that mechanical forces extensively inform the biological behaviour of liver cells in health and disease. Recent research has elucidated many cellular and molecular mechanisms involved in this process including the pleiotropic control and diverse effects of the paralogous transcription co-activators YAP/TAZ, which play a prominent role in mechanotransduction. The liver sinusoids represent a unique microenvironment in which cells are exposed to mechanical cues originating in the cytoskeleton and at interfaces with adjacent cells, the extracellular matrix, and vascular or interstitial fluids. In non-alcoholic fatty liver disease (NAFLD), hepatocellular lipid accumulation and ballooning, activation of inflammatory responses, dysfunction of liver sinusoidal endothelial cells, and transdifferentiation of hepatic stellate cells into a pro-contractile and pro-fibrotic phenotype have been associated with aberrant cycles of mechanosensing and mechanoresponses. The downstream consequences of disrupted mechanical homeostasis likely contribute to the progression of NAFLD and promote the development of portal hypertension, cirrhosis, and hepatocellular carcinoma. Identification of molecular targets involved in pathogenic mechanotransduction will allow for the development of novel strategies to prevent the progression of liver disease in NAFLD.

Reconstructing the portal vein through a posterior pancreatic tunnel: New choice for portal vein thrombosis during liver transplantation

BACKGROUND

Thrombectomy and anatomical anastomosis (TAA) has long been considered the optimal approach to portal vein thrombosis (PVT) in liver transplantation (LT). However, TAA and the current approach for non-physiological portal reconstructions are associated with a higher rate of complications and mortality in some cases.

AIM

To describe a new choice for reconstructing the portal vein through a posterior pancreatic tunnel (RPVPPT) to address cases of unresectable PVT.

METHODS

Between August 2019 and August 2021, 245 adult LTs were performed. Forty-five (18.4%) patients were confirmed to have PVT before surgery, among which seven underwent PV reconstruction via the RPVPPT approach. We retrospectively analyzed the surgical procedure and postoperative complications of these seven recipients that underwent PV reconstruction due to PVT.

RESULTS

During the procedure, PVT was found in all the seven cases with significant adhesion to the vascular wall and could not be dissected. The portal vein proximal to the superior mesenteric vein was damaged in one case when attempting thrombolectomy, resulting in massive bleeding. LT was successfully performed in all patients with a mean duration of 585 min (range 491-756 min) and mean intraoperative blood loss of 800 mL (range 500-3000 mL). Postoperative complications consisted of chylous leakage (n = 3), insufficient portal venous flow to the graft (n = 1), intra-abdominal hemorrhage (n = 1), pulmonary infection (n = 1), and perioperative death (n = 1). The remaining six patients survived at 12-17 mo follow-up.

CONCLUSION

The RPVPPT technique might be a safe and effective surgical procedure during LT for complex PVT. However, follow-up studies with large samples are still warranted due to the relatively small number of cases.

Case Report: Interventional therapy for portal venous stenosis caused by systemic vasculitis

Systemic vasculitis are multisystem blood vessel disorders. However, Portal venous involvement is extremely rare, which represents a diagnostic and therapeutic challenge due to the heterogeneous nature, a lack of diagnostic criteria and limited effective therapy of vasculitis. We have reported a 48-year-old woman who was previously diagnosed with systemic vasculitis and was treated with prednisone, presented with gastrointestinal (GI) bleeding on admission. Further abdominal contrast-enhanced computed tomography (CT) with three-dimensional reconstruction suggested atrophic left hepatic lobe, enlarged spleen, and severe stenosis of main portal vein. Liver biopsy showed no evidence of fibrosis/cirrhosis. To prevent rebleeding, portal venous angioplasty by balloon dilation with collateral varices embolization was performed, and the GI hemorrhage was resolved completely. However, refractory ascites presented 8 months postoperatively. Abdominal CT angiography confirmed the recurrence of portal venous stenosis. Portal venous angioplasty by stent implantation was then performed to treat the portal hypertension (PHT)-related complications. After the intervention, the patient received anticoagulation therapy and continued immunosuppressive therapy. During the 5-year follow-up, the patient did not experience any onset of GI bleeding or ascites. Therefore, portal venous angioplasty with stent placement could be an effective treatment to prevent PHT-related complications when immunosuppression therapy failed.

Bibliometric-analysis visualization and review of non-invasive methods for monitoring and managing the portal hypertension

Background

Portal hypertension monitoring is important throughout the natural course of cirrhosis. Hepatic venous pressure gradient (HVPG), regarded as the golden standard, is limited by invasiveness and technical difficulties. Portal hypertension is increasingly being assessed non-invasively, and hematological indices, imaging data, and statistical or computational models are studied to surrogate HVPG. This paper discusses the existing non-invasive methods based on measurement principles and reviews the methodological developments in the last 20 years.

Methods

First, we used VOSviewer to learn the architecture of this field. The publications about the non-invasive assessment of portal hypertension were retrieved from the Web of Science Core Collection (WoSCC). VOSviewer 1.6.17.0 was used to analyze and visualize these publications, including the annual trend, the study hotspots, the significant articles, authors, journals, and organizations in this field. Next, according to the cluster analysis result of the keywords, we further retrieved and classified the related studies to discuss.

Results

A total of 1,088 articles or review articles about our topic were retrieved from WoSCC. From 2000 to 2022, the number of publications is generally growing. “World Journal of Gastroenterology” published the most articles (n = 43), while “Journal of Hepatology” had the highest citations. “Liver fibrosis” published in 2005 was the most influential manuscript. Among the 20,558 cited references of 1,088 retrieved manuscripts, the most cited was a study on liver stiffness measurement from 2007. The highest-yielding country was the United States, followed by China and Italy. “Berzigotti, Annalisa” was the most prolific author and had the most cooperation partners. Four study directions emerged from the keyword clustering: (1) the evaluation based on fibrosis; (2) the evaluation based on hemodynamic factors; (3) the evaluation through elastography; and (4) the evaluation of variceal bleeding.

Conclusion

The non-invasive assessment of portal hypertension is mainly based on two principles: fibrosis and hemodynamics. Liver fibrosis is the major initiator of cirrhotic PH, while hemodynamic factors reflect secondary alteration of splanchnic blood flow. Blood tests, US (including DUS and CEUS), CT, and magnetic resonance imaging (MRI) support the non-invasive assessment of PH by providing both hemodynamic and fibrotic information. Elastography, mainly USE, is the most important method of PH monitoring.

Endoscopic tissue adhesive injection for gastric varices secondary to hepatic cirrhosis: Complications and management strategies

Gastric varices is a common clinical presentation of portal hypertension induced by hepatic cirrhosis, and gastric variceal bleeding is an emergency with high mortality. Endoscopic tissue adhesive injection plays an important role in the primary and secondary prophylaxis of gastric variceal bleeding, and acute bleeding control. However, this is a technique-demanding operation with nonnegligible complications, of which some may be fatal, such as ectopic embolism. Therefore, the prevention and treatment of such complications are of great importance. Herein, we present a review summarizing the complications and treatment strategies of endoscopic tissue adhesive injection for gastric varices secondary to hepatic cirrhosis.

Use of biochemical parameters for non-invasive screening of oesophageal varices in comparison to elastography-based approach in patients with compensated advanced chronic liver disease

Introduction

Oesophageal varices are routinely diagnosed by esophagogastroduodenoscopy (EGD), and their bleeding has high mortality. We aimed to evaluate diagnostic performance of biochemical tests in comparison to elastography-based approaches, as non-invasive alternatives to EGD, for ruling-out high risk oesophageal varices (HRV).

Material and methods

Retrospective analysis of patients (N = 861) who underwent liver stiffness measurement (LSM) by transient elastography (TE) in a single centre over 5-year period, with available results of EGD (within 3 months from LSM). Only patients with suspicion of compensated advanced chronic liver disease (cACLD) defined by LSM ≥ 10 kPa were included comprising the final cohort of 73 subjects. Original and expanded Baveno VI criteria (B6C), controlled attenuation parameter (CAP), platelet count (PLT), aspartate aminotransferase to PLT ratio index (APRI), Fibrosis-4 index (FIB4), model for end stage liver disease (MELD) score were evaluated against the results of EGD that served as the reference method.

Results

Analysed patients had median age 62 years, 59/73 (0.81) were males, 54/73 (0.74) had alcoholic/non-alcoholic fatty liver disease, and 21/73 (0.29) had HRV. In multivariate logistic regression analysis only LSM and PLT were independently associated with HRV. The best performing tests for ruling-out HRV (% of spared EGD; % of missed HRV) were respectively: LSM < 20 kPa (53.4%; 0%), B6C (38%; 0%), Expanded B6C (47.9%; 4.8%); PLT > 214x10⁹/L (21.9%; 0%); FIB4 ≤ 1.8 (21.4%; 0%), APRI ≤ 0.34 (12.3%; 0%). CAP, MELD = 6 alone or combined with PLT > 150(x10⁹/L) did not show acceptable performance.

Conclusion

The best performing biochemical tests for ruling-out HRV in our cohort of patients were PLT and FIB-4, but they were still outperformed by elastography-based approaches.

Reconstruction Algorithm-Based CT Imaging for the Diagnosis of Hepatic Ascites

The study was aimed at exploring the diagnostic value of artificial intelligence reconstruction algorithm combined with CT image parameters on hepatic ascites, expected to provide a reference for the etiological evaluation of clinical abdominal effusion. Specifically, the adaptive iterative hard threshold (AIHT) algorithm for CT image reconstruction was proposed. Then, 100 patients with peritoneal effusion were selected as the research subjects. After 8 cases were excluded, the remaining was divided into 50 cases of the S1 group (hepatic ascites) and 42 cases of the D0 group (cancerous peritoneal effusion). Gemstone energy spectrum CT scanning was performed on all patients, and CT image parameters of the two groups were compared. It was found that CT value of mixed energy, CT value of 60-100 KeV single energy, concentration value of water (calcium), concentration value of water (iodine), and slope of energy spectrum curve in the S1 group were significantly lower than those in the D0 group ( $P<0.05$ ). The effective atomic number in the S1 group was significantly higher than that in the D0 group ( $P<0.05$ ). Of the 50 patients in the S1 group, 3 (6%) had an ascending and 47 (94%) had a descending spectral curve. Of the 42 patients in the D0 group, 37 (88.1%) had an ascending and 5 (11.9%) had a descending spectral curve. The sensitivity and specificity of water (iodine) were 0.927 and 0.836, respectively. The sensitivity and specificity of water (calcium) were 0.863 and 0.887, respectively. For different scan ranges ([0,90]; [0,120]), root mean square error (RMSE) of AIHT reconstructed image was significantly smaller than that of traditional algorithm, while peak signal-to-noise ratio (PSNR) was opposite. The differences were statistically significant ( $P<0.05$ ). In conclusion, AIHT-based CT images can better display the distribution of hepatic ascites, and the parameters of CT value, effective atomic number, water (iodine), water (calcium), and spectral curve can all provide help for the identification of hepatic ascites. Especially, water (iodine) and water (calcium) demonstrated high diagnostic performance of hepatic ascites.

Downregulation of Ca2+-Activated Cl- Channel TMEM16A Mediated by Angiotensin II in Cirrhotic Portal Hypertensive Mice

Portal hypertension is defined as an increased pressure in the portal venous system and occurs as a major complication in chronic liver diseases. The pathological mechanism underlying the pathogenesis and development of portal hypertension has been extensively investigated. Vascular tone of portal vein smooth muscles (PVSMs) is regulated by the activities of several ion channels, including Ca²⁺-activated Cl^- (Cl_Ca) channels. TMEM16A is mainly responsible for Cl_Ca channel conductance in vascular smooth muscle cells, including portal vein smooth muscle cells (PVSMCs). In the present study, the functional roles of TMEM16A channels were examined using two experimental portal hypertensive models, bile duct ligation (BDL) mice with cirrhotic portal hypertension and partial portal vein ligation (PPVL) mice with non-cirrhotic portal hypertension. Expression analyses revealed that the expression of TMEM16A was downregulated in BDL-PVSMs, but not in PPVL-PVSMs. Whole-cell Cl_Ca currents were smaller in BDL-PVSMCs than in sham- and PPVL-PVSMCs. The amplitude of spontaneous contractions was smaller and the frequency was higher in BDL-PVSMs than in sham- and PPVL-PVSMs. Spontaneous contractions sensitive to a specific inhibitor of TMEM16A channels, T16A_inh-A01, were reduced in BDL-PVSMs. Furthermore, in normal PVSMs, the downregulation of TMEM16A expression was mimicked by the exposure to angiotensin II, but not to bilirubin. This study suggests that the activity of Cl_Ca channels is attenuated by the downregulation of TMEM16A expression in PVSMCs associated with cirrhotic portal hypertension, which is partly mediated by increased angiotensin II in cirrhosis.

Microbiota transplantation in portal hypertension: promises and pitfalls

In this commentary, we discuss new findings indicating that microbiota transplantation has favorable impact on portal hypertension (PH) in the experimental model of cirrhosis induced by bile duct ligation (BDL) (Huang et al.; Clin Sci (Lond) (2021) 135(24): 2709-2728, doi: 10.1042/CS20210602). Sinusoidal PH is an ominous outcome of advanced chronic liver disease, characterized by increased intrahepatic vascular resistance (IHVR), splanchnic hyperemia, and the development of portosystemic collaterals. In the work of Huang et al., microbiota transplantation not only alleviated splanchnic hyperdynamic circulation by improving vascular responsiveness and decreasing mesenteric angiogenesis, but also reduced blood flow in portosystemic collaterals. Surprisingly, however, microbiota transplantation had no effect on intrahepatic vasoconstriction in this experimental model. We discuss these observations in the context of recent literature showing that manipulation of the gut microbiota (either by transplantation or through the use of probiotics) may improve IHVR, which is one of the earliest abnormalities in the pathogenesis of sinusoidal PH. Further research is needed to explore the specific molecular and cellular targets associated with the correction of dysbiosis in liver disease.

Experimental model of portal hypertension and esophagogastric varices in minipigs: pressure and endoscopic pilot study

INTRODUCTION

Portal hypertension still represents an important health problem worldwide. In the search for knowledge regarding this syndrome, experimental studies with animal models have proven to be useful to point the direction to be taken in future randomized clinical trials.

PURPOSE

To validate the experimental model of portal hypertension and esophagogastric varices in a medium-sized animal.

METHODS

This study included five minipigs br1. Midline laparotomy with dissection of the portal vein and production of a calibrated stenosis of this vein was performed. Measurement of pressure in the portal venous and digestive endoscopic were performed before and five weeks after the production of a stenosis.

RESULTS

All animals were 8 months old, average weight of 17 ± 2.5 kg. The mean pressure of the portal vein immediately before the partial ligation of the portal vein was 8.9 + 1.6 mm Hg, with 26.6 + 5.4 mm Hg in the second measurement five weeks later (p < 0.05). No gastroesophageal varices or hypertensive portal gastropathy were seen at endoscopy procedures in our sample at any time in the study.

CONCLUSION

Portal vein ligation in minipigs has been validated in the production of portal hypertension, but not in the formation of esophageal varices.

Serum Expression Level of MicroRNA-122 and Its Significance in Patients with Hepatitis B Virus Infection

OBJECTIVES

To analyze the expression of miR-122 and evaluate its significance in patients with HBV infection in different phases.

METHODS

Eleven chronic hepatitis B (CHB), 26 hepatitis B virus (HBV)-induced cirrhosis, 16 HBV-associated hepatocellular carcinoma (HCC) patients and 10 healthy control cases were enrolled. The serum levels of miR-122 were detected by RT-PCR and compared between healthy individuals and CHB at different stages.

RESULTS

Compared with healthy control cases, serum miR-122 levels were markedly increased in HBV infection cases (AUC = 0.795, P=0.002). In the CHB group, miR-122 levels were positively associated with albumin levels (P < 0.05) but had no significant associations with alanine aminotransferase (ALT) and aspartate aminotransferase (AST) (P > 0.05). In the cirrhosis group, miR-122 expression was remarkably lower in the Child C group in comparison with the Child A group (P=0.025). At the same time, miR-122 amounts had a negative correlation with HVPG (P < 0.05). In the HCC group, miR-122 amounts were negatively associated with alkaline phosphatase (AKP) and alpha-fetoprotein (AFP) (P < 0.05). Serum miR-122 amounts in 3 patients who died were lower than the survival group (5.520 ± 0.522 vs. 5.860 ± 1.183, P > 0.05).

CONCLUSION

Serum miR-122 can be leveraged to screen patients with HBV infection. In HBV sufferers, the serum miR-122 expression level is related to liver disease progression, hence making it an underlying molecular biomarker for predicting the development of CHB.

Overlooked subclinical portal hypertension in non-cirrhotic NAFLD: Is it real and how to measure it?

Clinical and experimental advances related to the detection, magnitude and pathobiology of subclinical portal hypertension in non-alcoholic fatty liver disease (NAFLD), primarily observed in the presence of non-alcoholic steatohepatitis (NASH), prompt us to revisit current disease paradigms. Hepatic venous pressure gradient (HVPG) has been reported to underestimate portal pressure in NASH-related cirrhosis, while inaccuracy is more likely in non-cirrhotic livers, indicating a potential need for new and preferably non-invasive methods of measurement. Although clinically significant portal hypertension (HVPG ≥10 mmHg) retains its prognostic significance in NASH, subclinical portal hypertension (HVPG 6.0-9.5 mmHg) has been repeatedly detected in patients with NAFLD in the absence of cirrhosis or even significant fibrosis whereas the impact of these findings on disease outcomes remains unclear. Mechanocrine signalling pathways in various types of liver cell reveal a molecular basis for the adverse effects of subclinical portal hypertension and suggest a bidirectional relationship between portal pressure and fibrosis. These findings may guide efforts to improve risk assessment and identify novel therapeutic targets in NAFLD.

Angioplasty With Stent Implantation for Portal Venous Stenosis Caused by Abdominal Tuberculosis: A Case Report and Literature Review

Abdominal tuberculosis is one of common forms of extra-pulmonary tuberculosis. However, portal vein involvement leading to portal venous stenosis and portal hypertension is a rare complication in abdominal tuberculosis. Because of the non-specific presentations and insensitive response to anti-tuberculosis therapy of the lesions involving portal vein, it continues to be both a diagnostic and treatment challenge. We have reported a 22-year-old woman presented with massive ascites and pleural effusion, which was proved to be TB infection by pleural biopsy. After standard anti-tuberculosis therapy, her systemic symptoms completely resolved while ascites worsened with serum-ascites albumin gradient >11 g/L. Contrast-enhanced computed tomography and portal venography showed severe main portal vein stenosis from compression by multiple calcified hilar lymph nodes. Finally, the patient was diagnosed with portal venous stenosis due to lymphadenopathy after abdominal tuberculosis infection. Portal venous angioplasty by balloon dilation with stent implantation was performed and continued anti-tuberculosis therapy were administrated after discharge. The ascites resolved promptly with no recurrence occurred during the six-month follow-up. Refractory ascites due to portal venous stenosis is an uncommon vascular complication of abdominal tuberculosis. Portal venous angioplasty with stent placement could be a safe and effective treatment for irreversible vascular lesions after anti-tuberculosis therapy.

Cyclic GMP in Liver Cirrhosis-Role in Pathophysiology of Portal Hypertension and Therapeutic Implications

The NO-cGMP signal transduction pathway plays a crucial role in tone regulation in hepatic sinusoids and peripheral blood vessels. In a cirrhotic liver, the key enzymes endothelial NO synthase (eNOS), soluble guanylate cyclase (sGC), and phosphodiesterase-5 (PDE-5) are overexpressed, leading to decreased cyclic guanosine-monophosphate (cGMP). This results in constriction of hepatic sinusoids, contributing about 30% of portal pressure. In contrast, in peripheral arteries, dilation prevails with excess cGMP due to low PDE-5. Both effects eventually lead to circulatory dysfunction in progressed liver cirrhosis. The conventional view of portal hypertension (PH) pathophysiology has been described using the "NO-paradox", referring to reduced NO availability inside the liver and elevated NO production in the peripheral systemic circulation. However, recent data suggest that an altered availability of cGMP could better elucidate the contrasting findings of intrahepatic vasoconstriction and peripheral systemic vasodilation than mere focus on NO availability. Preclinical and clinical data have demonstrated that targeting the NO-cGMP pathway in liver cirrhosis using PDE-5 inhibitors or sGC stimulators/activators decreases intrahepatic resistance through dilation of sinusoids, lowering portal pressure, and increasing portal venous blood flow. These results suggest further clinical applications in liver cirrhosis. Targeting the NO-cGMP system plays a role in possible reversal of liver fibrosis or cirrhosis. PDE-5 inhibitors may have therapeutic potential for hepatic encephalopathy. Serum/plasma levels of cGMP can be used as a non-invasive marker of clinically significant portal hypertension. This manuscript reviews new data about the role of the NO-cGMP signal transduction system in pathophysiology of cirrhotic portal hypertension and provides perspective for further studies.

Amelioration of systemic inflammation in advanced chronic liver disease upon beta-blocker therapy translates into improved clinical outcomes

OBJECTIVE

Systemic inflammation promotes the development of clinical events in patients with advanced chronic liver disease (ACLD). We assessed whether (1) non-selective beta blocker (NSBB) treatment initiation impacts biomarkers of systemic inflammation and (2) whether these changes in systemic inflammation predict complications and mortality.

DESIGN

Biomarkers of systemic inflammation, that is, white blood cell count (WBC), C reactive protein (CRP), interleukin-6 (IL-6) and procalcitonin (PCT) were determined at sequential hepatic venous pressure gradient (HVPG) measurements without NSBB and under stable NSBB intake. The influence of NSBB-related changes in systemic inflammation on the risk of decompensation and liver-related death was analysed using competing risk regression.

RESULTS

Our study comprised 307 stable patients with ACLD (Child-A: 77 (25.1%), Child-B: 161 (52.4%), Child-C: 69 (22.5%), median HVPG: 20 (IQR 17-24) mm Hg) including 231 (75.2%) with decompensated disease.WBC significantly decreased upon NSBB therapy initiation (median: -2 (IQR -19;+13)%, p=0.011) in the overall cohort. NSBB-related reductions of WBC (Child-C: -16 (-30;+3)% vs Child-B: -2 (-16;+16)% vs Child-A: +3 (-7;+13)%, p<0.001) and of CRP (Child-C: -26 (-56,+8)% vs Child-B: -16 (-46;+13)% vs Child-A: ±0 (-33;+33)%, p<0.001) were more pronounced in advanced stages of cirrhosis. The NSBB-associated changes in WBC correlated with changes in CRP (Spearman's ρ=0.228, p<0.001), PCT (ρ=0.470, p=0.002) and IL-6 (ρ=0.501, p=0.001), but not with changes in HVPG (ρ=0.097, p=0.088).An NSBB-related decrease in systemic inflammation (ie, WBC reduction ≥15%) was achieved by n=91 (29.6%) patients and was found to be an independent protective factor of further decompensation (subdistribution HR, sHR: 0.694 (0.49-0.98), p=0.038) in decompensated patients and of liver-related mortality in the overall patient cohort (sHR: 0.561 (0.356-0.883), p=0.013).

CONCLUSION

NSBB therapy seems to exert systemic anti-inflammatory activity as evidenced by reductions of WBC and CRP levels. Interestingly, this effect was most pronounced in Child-C and independent of HVPG response. An NSBB-related WBC reduction by ≥15% was associated with a decreased risk of further decompensation and death.

Two novel online nomograms for predicting the survival of individual patients undergoing partial hepatectomy for huge hepatocellular carcinoma

BACKGROUND

A method for predicting prognosis of patients who undergo partial hepatectomy for huge hepatocellular carcinoma (HHCC, diameter ≥10 cm) is currently lacking. This study aimed to establish two online nomograms to predict the overall survival (OS) and disease-free survival (DFS) for patients undergoing resection for HHCC.

METHODS

The clinicopathologic characteristics and follow-up information of patients who underwent partial hepatectomy for HHCC at two medical centers were reviewed. Using a training cohort, a Cox model was used to identify the predictors of survival. Two dynamic nomograms for OS and DFS were developed and validated based on the data.

RESULTS

Eight and nine independent factors derived from the multivariate analysis of the training cohort were screened and incorporated into the nomograms for OS and DFS, respectively. In the training cohort, the nomogram achieved concordance indices (C-indices) of 0.745 and 0.738 in predicting the OS and DFS, respectively. These results were supported by external validation (C-indices: 0.822 for OS and 0.827 for DFS). Further, the calibration curves of the endpoints showed a favorable agreement between the nomograms' assessments and actual observations.

CONCLUSIONS

The two web-based nomograms demonstrated optimal predictive performance for patients undergoing partial hepatectomy for HHCC. This provides a practical method for a personalized prognosis based on an individual's underlying risk factors.

Portal hypertension in cirrhosis: Pathophysiological mechanisms and therapy

Portal hypertension, defined as increased pressure in the portal vein, develops as a consequence of increased intrahepatic vascular resistance due to the dysregulation of liver sinusoidal endothelial cells (LSECs) and hepatic stellate cells (HSCs), frequently arising from chronic liver diseases. Extrahepatic haemodynamic changes contribute to the aggravation of portal hypertension. The pathogenic complexity of portal hypertension and the unsuccessful translation of preclinical studies have impeded the development of effective therapeutics for patients with cirrhosis, while counteracting hepatic and extrahepatic mechanisms also pose a major obstacle to effective treatment. In this review article, we will discuss the following topics: i) cellular and molecular mechanisms of portal hypertension, focusing on dysregulation of LSECs, HSCs and hepatic microvascular thrombosis, as well as changes in the extrahepatic vasculature, since these are the major contributors to portal hypertension; ii) translational/clinical advances in our knowledge of portal hypertension; and iii) future directions.

Endothelial p300 Promotes Portal Hypertension and Hepatic Fibrosis Through C-C Motif Chemokine Ligand 2-Mediated Angiocrine Signaling

BACKGROUND AND AIMS

During liver fibrosis, liver sinusoidal endothelial cells (LSECs) release angiocrine signals to recruit inflammatory cells into the liver. p300, a master regulator of gene transcription, is associated with pathological inflammatory response. Therefore, we examined how endothelial p300 regulates angiocrine signaling and inflammation related to portal hypertension and fibrogenesis.

APPROACH AND RESULTS

CCl₄ or partial inferior vena cava ligation (pIVCL) was used to induce liver injury. Mice with LSEC-specific p300 deletion (p300^LSECΔ/Δ ) or C-C motif chemokine ligand 2 (Ccl2) deficiency, nuclear factor kappa B (NFκB)-p50 knockout mice, and bromodomain containing 4 (BRD4) inhibitors in wild-type mice were used to investigate mechanisms of inflammation regulation. Leukocytes were analyzed by mass cytometry by time-of-flight. Epigenetic histone marks were modified by CRISPR endonuclease-deficient CRISPR-associated 9-fused with the Krüppel associated box domain (CRISPR-dCas9-KRAB)-mediated epigenome editing. Portal pressure and liver fibrosis were reduced in p300^LSECΔ/Δ mice compared to p300^fl/fl mice following liver injury. Accumulation of macrophages was also reduced in p300^LSECΔ/Δ mouse livers. Ccl2 was the most up-regulated chemokine in injured LSECs, but its increase was abrogated in p300^LSECΔ/Δ mice. While the macrophage accumulation was increased in NFκB-p50 knockout mice with enhanced NFκB activity, it was reduced in mice with LSEC-specific Ccl2 deficiency and mice treated with specific BRD4 inhibitors. In vitro, epigenome editing of CCL2 enhancer and promoter regions by CRISPR-dCas9-KRAB technology repressed TNFα-induced CCL2 transcription through H3K9 trimethylation. In contrast, TNFα activated CCL2 transcription by promoting p300 interaction with NFκB and BRD4, leading to histone H3 lysine 27 acetylation at CCL2 enhancer and promoter regions.

CONCLUSIONS

In summary, endothelial p300 interaction with NFκB and BRD4 increases CCL2 expression, leading to macrophage accumulation, portal hypertension, and liver fibrosis. Inhibition of p300 and its binding partners might serve as therapy in the treatment of liver diseases.

Per-rectal portal scintigraphy as an alternative measure of hepatic venous pressure gradient in chronic liver disease: A preliminary report

AIM

Hepatic venous pressure gradient (HVPG) measurement is a gold standard for the diagnosis of portal hypertension but can be invasive and difficult to conduct. Per-rectal portal scintigraphy (PRPS) can estimate portal haemodynamics noninvasively. However, no report to date has examined the association between HVPG and PRPS in patients with chronic liver disease, including cirrhosis.

METHODS

This single-centre study included a total of 21 patients with chronic liver disease who underwent HVPG measurement and PRPS. For PRPS, the transit times from injection of the radiotracer to its inflow into the liver (TTL) and heart (TTH) were set and the time difference between TTL and TTH (TDLH) was calculated, while the shunt index (SI) was measured.

RESULTS

Cirrhosis was observed in 18 cases (86%), and the median HVPG was 13 mmHg. HVPG (p = 0.028), TTL (p = 0.018), TDLH (p = 0.003) and SI (p = 0.033) were higher in patients with oesophageal varices (EV). Considering the diagnostic ability for EV, the area under the curve was 0.88 for TDLH and 0.80 for HVPG. TDLH was significantly correlated with the risk of EV rupture (p = 0.004).

CONCLUSION

Patients with chronic liver disease should undergo upper gastrointestinal endoscopy when the TDLH is high.

Gastroesophageal varices in a patient presenting with essential thrombocythemia: A case report

BACKGROUND

Gastroesophageal varices are a rare complication of essential thrombocythemia (ET). ET is a chronic myeloproliferative neoplasm (MPN) characterized by an increased number of blood platelets.

CASE SUMMARY

A 46-year-old woman, who denied a history of liver disease, was admitted to our hospital on presentation of hematemesis. Laboratory examination revealed a hemoglobin level of 83 g/L, and a platelet count of 397 × 10⁹/L. The appearance of gastric and esophageal varices with red colored signs as displayed by an urgent endoscopy was followed by endoscopic variceal ligation and endoscopic tissue adhesive. Abdominal computed tomography revealed cirrhosis, marked splenomegaly, portal vein thrombosis and portal hypertension. In addition, bone marrow biopsy and evidence of mutated Janus kinase 2, substantiated the onset of ET. The patient was asymptomatic with regular routine blood testing during the 6-mo follow-up period. Therefore, in this case, gastroesophageal varices were induced by ET.

CONCLUSION

MPN should be given considerable attention when performing differential diagnoses in patients with gastroesophageal varices. An integrated approach such as laboratory tests, radiological examination, and pathological biopsy, should be included to allow optimal decisions and management.

EUS-guided portal pressure gradient measurement in patients with acute or subacute portal hypertension

BACKGROUND AND AIMS

EUS-guided portal pressure gradient (EUS-PPG) measurement is a novel method to evaluate portal hypertension severity. In this study, we determined the consistency between EUS-PPG and hepatic venous pressure gradient (HVPG) measurements in patients with acute or subacute portal hypertension.

METHODS

Twelve patients were prospectively enrolled. EUS-PPG measurements were performed using a 22-gauge FNA needle and a central venous pressure measurement monitor. The HVPG measurements were performed using the transjugular approach. If an HVPG measurement was not attainable and the patient underwent transjugular intrahepatic portosystemic shunt (TIPS) treatment, a PPG was recorded as a reference standard during the procedure. We assessed the feasibility and safety of EUS-PPG and calculated the correlation between the 2 measurements.

RESULTS

EUS-PPG measurements were successful in 11 patients (91.7%). Subsequent HVPG measurements failed in 2 patients with Budd-Chiari syndrome (hepatic vein occlusion subtype), 1 of whom underwent TIPS treatment to obtain transjugular PPG data. A small shunt was found during 1 HVPG measurement that introduced inaccuracy. Nine patients were included in the statistical analysis. Mean EUS-PPG and HVPG/PPG (transjugular) were 18.07 ± 4.32 mm Hg and 18.82 ± 3.43 mm Hg, respectively. Pearson's correlation coefficient between the 2 methods was .923 (P < .001).

CONCLUSIONS

EUS-PPG measurement using a 22-gauge FNA needle was a safe and accurate method to evaluate portal hypertension and has the potential to supplement the measurement of HVPG in liver diseases. (Clinical trial registration number: ChiCTR1800017317.).

Splenectomy before hepatectomy for patients with hepatocellular carcinoma and hypersplenism: A retrospective study

The spleen plays an important role in tumor progression and the curative effects of splenectomy before hepatectomy for hypersplenism and hepatocellular carcinoma (HCC) are not clear. We investigated whether splenectomy before hepatectomy increases survival rate among patients with HCC and hypersplenism compared with that of patients who underwent synchronous hepatectomy and splenectomy or hepatectomy alone.Between January 2011 and December 2016, 266 patients who underwent hepatectomy as a result of HCC and portal hypertension secondary to hepatitis were retrospectively analyzed. Their perioperative complications and survival outcome were evaluated.Patients underwent synchronous hepatectomy and splenectomy (H-S group) and underwent splenectomy before hepatectomy (H-preS group) exhibited significantly higher disease-free survival (DFS) rates than those of patients underwent hepatectomy alone (H-O group). The DFS rates for patients in the H-S group, H-preS group, and H-O group were 74.6%, 48.4%, 39.8%, and 80.1%, 54.2%, 40.1%, and 60.5%, 30.3%, 13.3%, at 1, 3, and 5 years after surgery, respectively. Tumor size, tumors number, and levels of alpha fetoprotein (AFP) were independent risk factors for DFS. Gender and tumor size were independent prognostic factor for overall survival (OS). The preoperative white blood cell (WBC) and platelet (PLT) counts were significantly higher in the H-preS group than in those of the H-S group and the H-O group. After operation, the WBC and PLT counts in the H-S group and H-preS groups were significantly higher compared to those of the H-O group.No matter splenectomy before hepatectomy or synchronous hepatectomy and splenectomy, hepatectomy with splenectomy may improve DFS rates in patients with HCC and hypersplenism, and splenectomy before hepatectomy alleviates hypersplenism without an increased surgical risk.

Selective Esophagogastric Devascularization in the Modified Sugiura Procedure for Patients with Cirrhotic Hemorrhagic Portal Hypertension: A Randomized Controlled Trial

AIM

Portal hypertension is a series of syndrome commonly seen with advanced cirrhosis, which seriously affects patient's quality of life and survival. This study was designed to access the efficacy and safety of selective esophagogastric devascularization in the modified Sugiura procedure for patients with cirrhotic hemorrhagic portal hypertension.

METHODS

Sixty patients with hepatitis B cirrhotic hemorrhagic portal hypertension and meeting the inclusion criteria were selected and randomly divided by using computer into the selective modified Sugiura group (sMSP group, n = 30) and the modified Sugiura group (MSP group, n = 30). The primary endpoint measurement is the postoperative rebleeding rate. Secondary endpoint measurements included free portal venous pressure, liver Child-Pugh score, liver volume, portal vein width and blood flow velocity, survival rate, quality of life, and dysphagia as well as other complications one year postoperatively. This trial is registered with ChiCTR, number ChiCTR2000033468.

RESULTS

There was no statistically significant difference in rebleeding rates within one year after surgery between patients in the sMSP and MSP groups (χ = 0.11, p=0.73). In comparison with the MSP group, the Child-Pugh score of liver function in the sMSP group significantly increased (χ = 6.4, p=0.04) and the incidence of dysphagia was significantly reduced (χ = 6.23, p=0.01) one year after surgery. There was a statistically significant difference in the quality of life between the two groups. However, there were no statistically significant differences in free portal venous pressure (MD = -3.44, 95% CI: -7.87 to 0.98, p=0.12), postoperative liver volume (3 months: MD = -258.81, 95% CI: -723.21 to 205.57, p=0.24; 1 year: MD = -320.12, 95% CI: -438.43 to 102.78, p=0.16), postoperative portal vein width (3 months: MD = -0.06, p=0.50; 1 year: MD = 0.17, p=0.21), portal vein flow velocity (3 months: MD = 1.64, p=0.21; 1 year: MD = -1.19, p=0.57), 1-year survival rate (χ = 1.01, p=0.31), and other complications between the two groups.

CONCLUSIONS

Selective esophagogastric devascularization in the modified Sugiura procedure may not lower the incidence of rebleeding in the short term based on our findings. However, it may significantly improve quality of life of patients with cirrhotic hemorrhagic portal hypertension, improve liver function, and reduce postoperative dysphagia.