Patients With Signs of Advanced Liver Disease and Clinically Significant Portal Hypertension Do Not Necessarily Have Cirrhosis

A roadmap for clinical trials in MASH-related compensated cirrhosis

Although metabolic dysfunction-associated steatohepatitis (MASH) is rapidly becoming a leading cause of cirrhosis worldwide, therapeutic options are limited and the number of clinical trials in MASH-related compensated cirrhosis is low as compared to those conducted in earlier disease stages. Moreover, designing clinical trials in MASH cirrhosis presents a series of challenges regarding the understanding and conceptualization of the natural history, regulatory considerations, inclusion criteria, recruitment, end points and trial duration, among others. The first international workshop on the state of the art and future direction of clinical trials in MASH-related compensated cirrhosis was held in April 2023 at Vall d'Hebron University Hospital in Barcelona (Spain) and was attended by a group of international experts on clinical trials from academia, regulatory agencies and industry, encompassing expertise in MASH, cirrhosis, portal hypertension, and regulatory affairs. The presented Roadmap summarizes important content of the workshop on current status, regulatory requirements and end points in MASH-related compensated cirrhosis clinical trials, exploring alternative study designs and highlighting the challenges that should be considered for upcoming studies on MASH cirrhosis.

Pathophysiology and therapeutic options for cirrhotic portal hypertension

Portal hypertension represents the primary non-neoplastic complication of liver cirrhosis and has life-threatening consequences, such as oesophageal variceal bleeding, ascites, and hepatic encephalopathy. Portal hypertension occurs due to increased resistance of the cirrhotic liver vasculature to portal blood flow and is further aggravated by the hyperdynamic circulatory syndrome. Existing knowledge indicates that the profibrogenic phenotype acquired by sinusoidal cells is the initial factor leading to increased hepatic vascular tone and fibrosis, which cause increased vascular resistance and portal hypertension. Data also suggest that the phenotype of hepatic cells could be further impaired due to the altered mechanical properties of the cirrhotic liver itself, creating a deleterious cycle that worsens portal hypertension in the advanced stages of liver disease. In this Review, we discuss recent discoveries in the pathophysiology and treatment of cirrhotic portal hypertension, a condition with few pharmacological treatment options.

Mild Thrombocytopenia, a Predictor of Outcomes After Laparoscopic Cholecystectomy: Assessment of Surgical Risk in Patients With Metabolic Dysfunction-Associated Steatotic Liver Disease

BACKGROUND

A common cause of mild thrombocytopenia is chronic liver disease, the most common etiology being metabolic dysfunction-associated steatotic liver disease (MASLD). Mild thrombocytopenia is a well-defined, independent marker of hepatic fibrosis in patients with chronic liver disease. Currently, there is a paucity of information available to characterize perioperative risk in patients with MASLD; therefore, the characterization of perioperative morbidity is paramount. We used a platelet threshold of 150×10 9 as a surrogate for fibrosis in patients undergoing laparoscopic cholecystectomy to study its effect on perioperative complications and mortality.

PATIENTS AND METHODS

We queried the American College of Surgeons National Surgical Quality Improvement Program database for laparoscopic cholecystectomies occurring from 2005 through 2018. Demographic differences between patients with and without thrombocytopenia were evaluated using the t test or the χ 2 test, whereas adjusted and unadjusted differences in outcome risk were evaluated using log-binomial regression models.

RESULTS

We identified 437,630 laparoscopic cholecystectomies of which 6.9% included patients with thrombocytopenia. Patients with thrombocytopenia were more often males, older, and with chronic disease. Patients with thrombocytopenia and higher Aspartate Aminotransferase to Platelet Ratio Index scores had 30-day mortality rates risk ratio of 5.3 (95% CI: 4.8-5.9), with higher complication rates risk ratio of 2.4 (95% CI: 2.3-2.5). The most frequent complications included the need for transfusion, renal, respiratory, and cardiac.

CONCLUSIONS

Perioperatively, patients with mild thrombocytopenia undergoing laparoscopic cholecystectomy had higher mortality rates and complications compared with patients with normal platelet counts. Thrombocytopenia may be a promising, cost-effective tool to identify patients with MASLD and estimate perioperative risk, especially if used in high-risk populations.

Diffusion-Weighted MRI of the Liver in Patients With Chronic Liver Disease: A Comparative Study Between Different Fitting Approaches and Diffusion Models

BACKGROUND

Diffusion-weighted imaging (DWI) has been considered for chronic liver disease (CLD) characterization. Grading of liver fibrosis is important for disease management.

PURPOSE

To investigate the relationship between DWI's parameters and CLD-related features (particularly regarding fibrosis assessment).

STUDY TYPE

Retrospective.

SUBJECTS

Eighty-five patients with CLD (age: 47.9 ± 15.5, 42.4% females).

FIELD STRENGTH/SEQUENCE

3-T, spin echo-echo planar imaging (SE-EPI) with 12 b-values (0-800 s/mm2 ).

ASSESSMENT

Several models statistical models, stretched exponential model, and intravoxel incoherent motion were simulated. The corresponding parameters (Ds , σ, DDC, α, f, D, D*) were estimated on simulation and in vivo data using the nonlinear least squares (NLS), segmented NLS, and Bayesian methods. The fitting accuracy was analyzed on simulated Rician noised DWI. In vivo, the parameters were averaged from five central slices entire liver to compare correlations with histological features (inflammation, fibrosis, and steatosis). Then, the differences between mild (F0-F2) or severe (F3-F6) groups were compared respecting to statistics and classification. A total of 75.3% of patients used to build various classifiers (stratified split strategy and 10-folders cross-validation) and the remaining for testing.

STATISTICAL TESTS

Mean squared error, mean average percentage error, spearman correlation, Mann-Whitney U-test, receiver operating characteristic (ROC) curve, area under ROC curve (AUC), sensitivity, specificity, accuracy, precision. A P-value <0.05 was considered statistically significant.

RESULTS

In simulation, the Bayesian method provided the most accurate parameters. In vivo, the highest negative significant correlation (Ds , steatosis: r = -0.46, D*, fibrosis: r = -0.24) and significant differences (Ds , σ, D*, f) were observed for Bayesian fitted parameters. Fibrosis classification was performed with an AUC of 0.92 (0.91 sensitivity and 0.70 specificity) with the aforementioned diffusion parameters based on the decision tree method.

DATA CONCLUSION

These results indicate that Bayesian fitted parameters may provide a noninvasive evaluation of fibrosis with decision tree.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY: Stage 1.

Possible use of 2D shear wave liver elastography in new-onset ascites evaluation

BACKGROUND

No data on the use of 2D shear wave elastography exists regarding the evaluation of the new-onset ascites causality.

AIMS

To determine whether 2D shear wave elastography can help in the non-invasive assessment of the new-onset ascites cause. To assess the applicability of liver stiffness measured by 2D shear wave elastography using Esaote MyLab Nine apparatus in patients with ascites.

METHODS

In 52 consecutive patients with new-onset ascites (January 2020 to October 2021), liver stiffness using 2D shear wave elastography was prospectively measured. The reliable measurements were used for further analysis. Relevant clinical and laboratory data was collected.

RESULTS

The calculated liver stiffness measurement cut-off value of 14.4 kPa held 94% accuracy, 100% sensitivity, and 83% specificity when determining ascites with serum ascites albumin gradient ≥11 g/L. Reliable 2D shear wave elastography success rate was 84%.

CONCLUSIONS

2D shear wave elastography may potentially be used to differentiate transudative from exudative ascites, especially in patients with portal hypertension and peritoneal carcinomatosis.

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.

MELD-Na score may underestimate disease severity and risk of death in patients with metabolic dysfunction-associated steatotic liver disease (MASLD)

Portal hypertension often precedes the development of advanced fibrosis in patients with Metabolic dysfunction-associated steatotic liver disease (MASLD) and may accelerate disease progression to cirrhosis. We aimed to evaluate whether prioritization tools accurately predict survival in patients with MASLD and clinically significant portal hypertension (CSPH). We retrospectively identified patients diagnosed with esophageal or gastric varices (EGV). Laboratory results, endoscopy reports and outcomes of patients with MASLD were compared to patients with advanced stage chronic liver disease (CLD) of other etiologies. During the study period 326 patients were diagnosed with EGV. 88 (26.9%) had MASLD, 113 (34.6%) viral hepatitis (VH), 63 (19.3%) alcoholic liver disease (ALD) and 62 (19%) both VH and ALD (VHALD). EGV bleeding events were significantly more frequent in patients with MASLD (36.3%), compared to VH (28.3%), ALD (30.1%) and VHALD (25.8%), respectively (p < 0.01). Mean Model for End-Stage Liver Disease (MELD)-Na score surrounding 1 year of first event of EGV bleeding was significantly lower in MASLD patients compared to all other etiologies (p = 0.02). At a MELD-Na score of 11-20, cumulative survival rate was significantly lower in MASLD patients compared to all other etiologies (log rank p < 0.01). MASLD patients present with EGV bleeding at lower MELD-Na scores compared to other etiologies of CLD. MELD-Na score may therefore underestimate disease severity and risk of death in patients with MASLD and CSPH.

Portal Hypertension in Nonalcoholic Fatty Liver Disease: Challenges and Paradigms

Portal hypertension in cirrhosis is defined as an increase in the portal pressure gradient (PPG) between the portal and hepatic veins and is traditionally estimated by the hepatic venous pressure gradient (HVPG), which is the difference in pressure between the free-floating and wedged positions of a balloon catheter in the hepatic vein. By convention, HVPG≥10 mmHg indicates clinically significant portal hypertension, which is associated with adverse clinical outcomes. Nonalcoholic fatty liver disease (NAFLD) is a common disorder with a heterogeneous clinical course, which includes the development of portal hypertension. There is increasing evidence that portal hypertension in NAFLD deserves special considerations. First, elevated PPG often precedes fibrosis in NAFLD, suggesting a bidirectional relationship between these pathological processes. Second, HVPG underestimates PPG in NAFLD, suggesting that portal hypertension is more prevalent in this condition than currently believed. Third, cellular mechanoresponses generated early in the pathogenesis of NAFLD provide a mechanistic explanation for the pressure-fibrosis paradigm. Finally, a better understanding of liver mechanobiology in NAFLD may aid in the development of novel pharmaceutical targets for prevention and management of this disease.

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.

Insight into increased risk of portal vein thrombosis in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is one of the leading chronic liver diseases with increased morbidity and mortality rates for extrahepatic diseases (including cardiovascular disease, portal vein thrombosis, etc.). There is an increased risk of thrombosis in both the portal and systemic circulation in patients with NAFLD, independent of traditional liver cirrhosis. However, increased portal pressure, the most critical factor, is frequently observed in NAFLD patients, predisposing them to portal vein thrombosis (PVT). It has been reported that there is an 8.5% incidence of PVT among patients with non-cirrhotic NAFLD in a prospective cohort study. Based on the prothrombotic status of NAFLD itself, patients combined with cirrhosis may accelerate the development of PVT and lead to a poor prognosis. Moreover, PVT has been shown to complicate the procedure and adversely affect the outcome during liver transplantation surgery. NAFLD is in a prothrombotic state, and its underlying mechanisms have not been fully understood so far. Particularly noteworthy is that gastroenterologists currently overlook the higher risk of PVT in NAFLD. We investigate the pathogenesis of NAFLD complicated with PVT from the perspective of primary, secondary, and tertiary hemostasis, and also summarize relevant studies in humans. Some treatment options that may affect NAFLD and its PVT are also explored to improve patient-oriented outcomes.

Non-invasive tools for compensated advanced chronic liver disease and portal hypertension after Baveno VII - an update

Non-invasive tests (NITs) and liver stiffness measurement (LSM) in particular, have entered clinical practice over 20 years ago as point-of-care tests to diagnose liver fibrosis in patients with compensated chronic liver disease. Since then, NITs use has evolved thanks to a large number of studies in all major etiologies of liver disease, and they have become important tools to stratify the risk of portal hypertension and liver-related events. The Baveno VII consensus workshop provided several novel recommendations regarding the use of well-established and novel NITs in the specific setting of portal hypertension screening, diagnosis and follow-up. The Baveno VII expert panels paid special attention to summarizing the existing data into simple clinical rules able to guide clinicians in their practice. The "rule of five" for LSM is a tool to stratify the risk of liver-related events, and LSM alone or in combination with platelet count, can be used now to rule-in and rule-out compensated advanced chronic liver disease (cACLD) and clinically significant portal hypertension, as well as to rule-out high-risk varices. Use of NITs in obese subjects with non-alcoholic fatty liver disease (NAFLD) and patients with viral hepatitis C that has been successfully treated, require specific knowledge. This review will update the reader on these aspects.

Nonalcoholic Fatty Liver Disease and Chronic Kidney Disease: Epidemiology, Pathogenesis, and Clinical and Research Implications

Nonalcoholic fatty liver disease (NAFLD) has become the most common cause of chronic liver disease worldwide, affecting up to ~30% of adult populations. NAFLD defines a spectrum of progressive liver conditions ranging from simple steatosis to nonalcoholic steatohepatitis (NASH), cirrhosis, and hepatocellular carcinoma, which often occur in close and bidirectional associations with metabolic disorders. Chronic kidney disease (CKD) is characterized by anatomic and/or functional renal damage, ultimately resulting in a reduced glomerular filtration rate. The physiological axis linking the liver and kidneys often passes unnoticed until clinically significant portal hypertension, as a major complication of cirrhosis, becomes apparent in the form of ascites, refractory ascites, or hepatorenal syndrome. However, the extensive evidence accumulated since 2008 indicates that noncirrhotic NAFLD is associated with a higher risk of incident CKD, independent of obesity, type 2 diabetes, and other common renal risk factors. In addition, subclinical portal hypertension has been demonstrated to occur in noncirrhotic NAFLD, with a potential adverse impact on renal vasoregulation. However, the mechanisms underlying this association remain unexplored to a substantial extent. With this background, in this review we discuss the current evidence showing a strong association between NAFLD and the risk of CKD, and the putative biological mechanisms underpinning this association. We also discuss in depth the potential pathogenic role of the hepatorenal reflex, which may be triggered by subclinical portal hypertension and is a poorly investigated but promising research topic. Finally, we address emerging pharmacotherapies for NAFLD that may also beneficially affect the risk of developing CKD in individuals with NAFLD.

Portal Hypertension in Nonalcoholic Fatty Liver Disease: From Pathogenesis to Clinical Practice

Portal hypertension in nonalcoholic fatty liver disease (NAFLD) mostly occur in cirrhotic stage. However, several experimental and clinical studies showed evidence of portal hypertension in NAFLD without significant or advance fibrosis. This early development of portal hypertension in NAFLD is associated with liver sinusoidal contraction by hepatocellular lipid accumulation and ballooning, which is also accompanied by capillarization and dysfunction of liver sinusoidal endothelial cells. Both of these impaired mechanical and molecular components can cause an increase in intrahepatic vascular resistance which lead to the increase of portal pressure in the absence of significant liver fibrosis. Extrahepatic factors such as insulin resistance and gut dysbiosis may also contribute to liver sinusoidal endothelial dysfunction and early portal hypertension in NAFLD. The clinical impact of early portal hypertension in NAFLD is still unclear. However, clinical tools for diagnosis and monitoring of portal hypertension in NAFLD are being investigated to predict high-risk patients and to guide therapy.

Comparison of prognoses between cirrhotic and noncirrhotic patients with hepatocellular carcinoma and esophageal varices undergoing surgical resection

BACKGROUND

Esophageal varices (EV) is common and is a poor prognostic factor for patients with hepatocellular carcinoma (HCC). However, the outcomes between cirrhotic and noncirrhotic HCC patients with EV is not well studied. The present study aimed to investigate the clinical manifestations and prognoses of HCC patients after surgical resection stratified by the cirrhosis status.

METHODS

A total of 111 patients with HCC and EV, who underwent surgical resection, were retrospectively enrolled between July 2003 and July 2019. The diagnosis of liver cirrhosis was established using the Ishak fibrosis score F5 or F6 in the nontumor part of liver specimens. Prognostic factors were analyzed using the Cox proportional hazards model.

RESULTS

There were 85 (76.6%) and 26 (23.4%) patients with and without cirrhosis, respectively. Compared with those without cirrhosis, there were more females, less seropositive rate of hepatitis B surface antigen (HBsAg), more seropositive rate of antibody against to hepatitis C virus (HCV), less albumin-bilirubin (ALBI) grade 1, lower platelet count, and more had tumor burden within the Milan criteria in cirrhotic patients. Cirrhotic patients had a higher risk of posthepatectomy decompensation compared to noncirrhotic patients (hazard ratio 9.577, p = 0.017). No difference was observed in overall survival and recurrence-free survival between patients with or without cirrhosis.

CONCLUSION

Compared with patients without cirrhosis, cirrhotic patients with HCC and EV are vulnerable to posthepatectomy decompensation. However, cirrhosis is not a poor prognostic factor of overall survival and recurrence for HCC patients after surgical resection.

Malaysian Society of Gastroenterology and Hepatology consensus statement on metabolic dysfunction-associated fatty liver disease

The Malaysian Society of Gastroenterology and Hepatology saw the need for a consensus statement on metabolic dysfunction-associated fatty liver disease (MAFLD). The consensus panel consisted of experts in the field of gastroenterology/hepatology, endocrinology, bariatric surgery, family medicine, and public health. A modified Delphi process was used to prepare the consensus statements. The panel recognized the high and increasing prevalence of the disease and the consequent anticipated increase in liver-related complications and mortality. Cardiovascular disease is the leading cause of mortality in MAFLD patients; therefore, cardiovascular disease risk assessment and management is important. A simple and clear liver assessment and referral pathway was agreed upon, so that patients with more severe MAFLD can be linked to gastroenterology/hepatology care, while patients with less severe MAFLD can remain in primary care or endocrinology, where they are best managed. Lifestyle intervention is the cornerstone in the management of MAFLD. The panel provided a consensus on the use of statin, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, sodium-glucose cotransporter-2 inhibitor, glucagon-like peptide-1 agonist, pioglitazone, vitamin E, and metformin, as well as recommendations on bariatric surgery, screening for gastroesophageal varices and hepatocellular carcinoma, and liver transplantation in MAFLD patients. Increasing the awareness and knowledge of the various stakeholders on MAFLD and incorporating MAFLD into existing noncommunicable disease-related programs and activities are important steps to tackle the disease. These consensus statements will serve as a guide on MAFLD for clinicians and other stakeholders.

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.

Portal Hypertension and Ascites: Patient-and Population-centered Clinical Practice Guidelines by the Italian Association for the Study of the Liver (AISF)

Portal hypertension and ascites are two crucial events in the natural history of liver cirrhosis, whose appearance marks a downward shift in the prognosis of the disease. Over the years, several international and national societies have issued clinical practice guidelines for the diagnosis and management of portal hypertension and ascites. The present document addresses the needs of an updated guidance on the clinical management of these conditions. Accordingly, the AISF Governing Board appointed a multi-disciplinary committee of experts for drafting an update of the most recent EASL Clinical Practice Guidelines. The aim of this work was to adapt the EASL recommendations to national regulations and resources, local circumstances and settings, infrastructure, and cost/benefit strategies to avoid duplication of efforts and optimize resource utilization. The committee defined the objectives, the key issues and retrieved the relevant evidence by performing a systematic review of the literature. Finally, the committee members (chosen on the basis of their specific expertise) identified the guidelines' key questions and developed them following the PICO format (Population, Intervention, Comparison, Outcomes). For each of the PICO questions, the systematic review of the literature was made on the most important scientific databases (Pubmed, Scopus, Embase).

Transjugular Liver Biopsy with Hemodynamic Evaluation: Correlation between Hepatic Venous Pressure Gradient and Histologic Diagnosis of Cirrhosis

Objectives:

Measurement of hepatic vein pressures is the accepted gold standard for the evaluation of portal hypertension. This study was conducted to evaluate the correlation between hepatic vein pressure measurements and histologic findings from transjugular liver biopsies. The hypothesis was that higher hepatic venous pressure gradients would correlate with a histologic diagnosis of cirrhosis.

Material and Methods:

We identified all patients who underwent transjugular liver biopsies at our institution between January 2015 and December 2019. Of these, 178 patients who had undergone hemodynamic evaluations during the biopsy procedure were included in the study. Demographic information and laboratory data were extracted from the patients’ electronic medical records. The hepatic vein pressure gradient (HVPG) was determined by subtracting the free hepatic venous pressure from the wedged hepatic venous pressure (WHVP), and the portosystemic gradient (PSG) was determined by subtracting the right atrial pressure from the WHVP. HVPG and PSG were compared by linear regression analysis and by calculating their receiver operating characteristics (ROC).

Results:

HVPG and PSG measurements were significantly associated with cirrhosis, with area under the ROC curve of 0.79 and 0.78, respectively. At the optimal cutoff of 9 mmHg, sensitivity and specificity for HVPG were 71% and 83% for HVPG and 67 % and 81% for PSG, respectively. No statistical difference was observed between the two measurements.

Conclusion:

A transhepatic venous pressure gradient above a cutoff of 9 mmHg is predictive of histologic cirrhosis, regardless of whether it is expressed as HVPG or PSG, with acceptable to excellent performance characteristics.

Cardiac Morphology, Function, and Hemodynamics in Patients With Morbid Obesity and Nonalcoholic Steatohepatitis

Background

The patients with nonalcoholic fatty liver disease demonstrate an increased cardiovascular risk. The adverse influence of liver abnormalities on cardiac function are among many postulated mechanisms behind this association. The aim of the study was to evaluate cardiac morphology and function in patients with morbid obesity referred for bariatric surgery with liver biopsy.

Methods and Results

We evaluated with echocardiography 171 consecutive patients without known cardiac disease (median age 42 [interquartile range, 37–48] years, median body mass index 43.7 [interquartile range, 41.0–47.5], 67% female patients. Based on the liver biopsy results, there were 44 patients with nonalcoholic steatohepatitis (NASH), 69 patients with isolated steatosis, and 58 patients without steatosis. Patients with NASH demonstrated signs of left ventricular concentric remodeling and hyperdynamic circulation, including indexed left ventricular end‐diastolic diameter [cm/m²]: NASH 1.87 [0.22]; isolated steatosis 2.03 [0.33]; without steatosis 2.01 [0.19], P=0.001; relative wall thickness: NASH 0.49±0.05, isolated steatosis 0.47±0.06, without steatosis 0.46±0.06, P=0.011; cardiac index [L/m²]: NASH 3.05±0.54, isolated steatosis 2.80±0.44, without steatosis 2.79±0.50, P=0.013. After adjustment for sex, age, blood pressure, and heart rate, most of the measures of the left ventricular systolic and diastolic function, left atrial size, right ventricular function, and right ventricular size did not differ between groups.

Conclusions

In a group of patients with extreme obesity, NASH was associated with left ventricular concentric remodeling and hyperdynamic circulation. Increased cardiac output in NASH may represent an additional risk factor for incident cardiovascular events in this population.

Undiagnosed liver diseases

The landscape of chronic liver disease has drastically changed over the past 20 years, largely due to advances in antiviral therapy and the rise of metabolic syndrome and associated non-alcoholic fatty liver disease (NAFLD). Despite advances in the diagnosis and treatment of a variety of liver diseases, the burden of chronic liver disease is increasing worldwide. The first step to addressing any disease is accurate diagnosis. Here, we discuss liver diseases that remain undiagnosed, either because they are difficult to diagnose or due to hepatic manifestations of an unrecognized systemic disease. Additionally, their underlying etiology may remain unknown or they represent previously uncharacterized and therefore novel liver diseases. Our goal is to provide a framework for approaching undiagnosed liver diseases which elude standard hepatic diagnostic work-up and whose patterns of disease are often overlooked.

Steatosis as main determinant of portal hypertension through a restriction of hepatic sinusoidal area in a dietary rat nash model

BACKGROUND & AIMS

Portal hypertension (PH) can be present in pre-cirrhotic stages, even in absence of fibrosis in non-alcoholic steatohepatitis (NASH) patients. Liver endothelial dysfunction (ED) has been shown as responsible for this effect in short-term dietary animal models. We evaluated the persistence of PH and underlying mechanisms in a long-term rat model of NASH.

METHODS

Sprague-Dawley rats were fed 8 or 36 weeks with control diet or high-fat high-glucose/fructose diet. Metabolic parameters, histology, ED and haemodynamics were characterized. Structural characteristics of liver sections were analysed using image analysis.

RESULTS

Both interventions reproduced NASH histological hallmarks (with steatosis being particularly increased at 36 weeks), but neither induced fibrosis. The 36-week intervention induced a significant increase in portal pressure (PP) compared to controls (12.1 vs 8.7 mmHg, P < .001) and the 8-week model (10.7 mmHg, P = .006), but all features of ED were normalized at 36 weeks. Image analysis revealed that the increased steatosis at 36-week was associated to an increase in hepatocyte area and a significant decrease in the sinusoidal area, which was inversely correlated with PP. The analysis provided a critical sinusoidal area above which animals were protected from developing PH and below which sinusoidal flux was compromised and PP started to increase.

CONCLUSION

Liver steatosis per se (in absence of fibrosis) can induce PH through a decrease in the sinusoidal area secondary to the increase in hepatocyte area in a long-term diet-induced rat model of NASH. Image analysis of the sinusoidal area might predict the presence of PH.

Nonalcoholic fatty liver disease and portal hypertension

Nonalcoholic fatty liver disease (NAFLD) is a substantial and growing problem worldwide and has become the second most common indication for liver transplantation as it may progress to cirrhosis and develop complications from portal hypertension primarily caused by advanced fibrosis and erratic tissue remodeling. However, elevated portal venous pressure has also been detected in experimental models of fatty liver and in human NAFLD when fibrosis is far less advanced and cirrhosis is absent. Early increases in intrahepatic vascular resistance may contribute to the progression of liver disease. Specific pathophenotypes linked to the development of portal hypertension in NAFLD include hepatocellular lipid accumulation and ballooning injury, capillarization of liver sinusoidal endothelial cells, enhanced contractility of hepatic stellate cells, activation of Kupffer cells and pro-inflammatory pathways, adhesion and entrapment of recruited leukocytes, microthrombosis, angiogenesis and perisinusoidal fibrosis. These pathological events are amplified in NAFLD by concomitant visceral obesity, insulin resistance, type 2 diabetes and dysbiosis, promoting aberrant interactions with adipose tissue, skeletal muscle and gut microbiota. Measurement of the hepatic venous pressure gradient by retrograde insertion of a balloon-tipped central vein catheter is the current reference method for predicting outcomes of cirrhosis associated with clinically significant portal hypertension and guiding interventions. This invasive technique is rarely considered in the absence of cirrhosis where currently available clinical, imaging and laboratory correlates of portal hypertension may not reflect early changes in liver hemodynamics. Availability of less invasive but sufficiently sensitive methods for the assessment of portal venous pressure in NAFLD remains therefore an unmet need. Recent efforts to develop new biomarkers and endoscopy-based approaches such as endoscopic ultrasound-guided measurement of portal pressure gradient may help achieve this goal. In addition, cellular and molecular targets are being identified to guide emerging therapies in the prevention and management of portal hypertension.