Invasive and non-invasive techniques for detecting portal hypertension and predicting variceal bleeding in cirrhosis: a review

Future directions of noninvasive prediction of esophageal variceal bleeding: No worry about the present computed tomography inefficiency

In this editorial, we comment on the minireview by Martino A, published in the recent issue of World Journal of Gastrointestinal Endoscopy 2023; 15 (12): 681-689. We focused mainly on the possibility of replacing the hepatic venous pressure gradient (HVPG) and endoscopy with noninvasive methods for predicting esophageal variceal bleeding. The risk factors for bleeding were the size of the varices, the red sign and the Child-Pugh score. The intrinsic core factor that drove these changes was the HVPG. Therefore, the present studies investigating noninvasive methods, including computed tomography, magnetic resonance imaging, elastography, and laboratory tests, are working on correlating imaging or serum marker data with intravenous pressure and clinical outcomes, such as bleeding. A single parameter is usually not enough to construct an efficient model. Therefore, multiple factors were used in most of the studies to construct predictive models. Encouraging results have been obtained, in which bleeding prediction was partly reached. However, these methods are not satisfactory enough to replace invasive methods, due to the many drawbacks of different studies. There is still plenty of room for future improvement. Prediction of the precise timing of bleeding using various models, and extracting the texture of variceal walls using high-definition imaging modalities to predict the red sign are interesting directions to lay investment on.

Predictors of Long-Term Rebleeding Risk in Cirrhotic Patients Undergoing Esophagogastric Devascularization and Splenectomy: Impact of Portal Vein Thrombosis and Hemoglobin Levels

BACKGROUND Esophagogastric devascularization and splenectomy (EGDS) is widely used to treat patients with portal hypertension in China. This study aimed to determine risk factors that increase risk of rebleeding after EGDS and evaluate the effect of portal vein thrombosis (PVT) on rebleeding rates after EGDS. MATERIAL AND METHODS Clinical data of patients with cirrhosis (n=138) who underwent EGDS between December 2010 and January 2016 were retrospectively analyzed. Patients were assigned to rebleeding or non-rebleeding groups and followed up. Univariate and multivariate Cox regression analyses identified the independent predictors of 3-year and 5-year rebleeding. RESULTS A total of 138 consecutive patients who underwent EGDS and met the inclusion criteria were enrolled. Total bilirubin (HR: 2.392, 95% CI 1.032-5.545, P=0.042) and PVT (HR: 3.345, 95% CI 1.477-7.573, P=0.004) predicted 3-year rebleeding during univariate analysis. Multivariate analysis revealed that PVT (HR: 3.967, 95% CI 1.742-9.035, P=0.001) was an independent predictor. Hemoglobin >87.5 g/L (HR: 3.104, 95% CI 1.283-7.510, P=0.012) and PVT (HR: 2.349, 95% CI 1.231-4.483, P=0.010) were predictors of 5-year rebleeding during multivariate analysis. Albumin >37.5 g/L was an independent predictor of rebleeding in patients with PVT at 3 and 5 years (HR: 3.964, 95% CI 1.301-9.883, P=0.008; HR: 3.193, 95% CI 1.275-7.997, P=0.013, respectively). CONCLUSIONS PVT is associated with increased 3-year and 5-year rebleeding rates after EGDS but not at 10 years. Also, hemoglobin >87.5 g/L predicted rebleeding at 5 years. Albumin has huge prospects as a predictor of rebleeding at 3 and 5 years in patients with PVT.

Non-invasive model for predicting high-risk esophageal varices based on liver and spleen stiffness

BACKGROUND

Acute bleeding due to esophageal varices (EVs) is a life-threatening complication in patients with cirrhosis. The diagnosis of EVs is mainly through upper gastrointestinal endoscopy, but the discomfort, contraindications and complications of gastrointestinal endoscopic screening reduce patient compliance. According to the bleeding risk of EVs, the Baveno VI consensus divides varices into high bleeding risk EVs (HEVs) and low bleeding risk EVs (LEVs). We sought to identify a non-invasive prediction model based on spleen stiffness measurement (SSM) and liver stiffness measurement (LSM) as an alternative to EVs screening.

AIM

To develop a safe, simple and non-invasive model to predict HEVs in patients with viral cirrhosis and identify patients who can be exempted from upper gastrointestinal endoscopy.

METHODS

Data from 200 patients with viral cirrhosis were included in this study, with 140 patients as the modelling group and 60 patients as the external validation group, and the EVs types of patients were determined by upper gastrointestinal endoscopy and the Baveno VI consensus. Those patients were divided into the HEVs group (66 patients) and the LEVs group (74 patients). The effect of each parameter on HEVs was analyzed by univariate and multivariate analyses, and a non-invasive prediction model was established. Finally, the discrimination ability, calibration ability and clinical efficacy of the new model were verified in the modelling group and the external validation group.

RESULTS

Univariate and multivariate analyses showed that SSM and LSM were associated with the occurrence of HEVs in patients with viral cirrhosis. On this basis, logistic regression analysis was used to construct a prediction model: Ln [P/(1-P)] = -8.184 -0.228 × SSM + 0.642 × LSM. The area under the curve of the new model was 0.965. When the cut-off value was 0.27, the sensitivity, specificity, positive predictive value and negative predictive value of the model for predicting HEVs were 100.00%, 82.43%, 83.52%, and 100%, respectively. Compared with the four prediction models of liver stiffness-spleen diameter to platelet ratio score, variceal risk index, aspartate aminotransferase to alanine aminotransferase ratio, and Baveno VI, the established model can better predict HEVs in patients with viral cirrhosis.

CONCLUSION

Based on the SSM and LSM measured by transient elastography, we established a non-invasive prediction model for HEVs. The new model is reliable in predicting HEVs and can be used as an alternative to routine upper gastrointestinal endoscopy screening, which is helpful for clinical decision making.

Gadoxetic acid-enhanced MRI-derived functional liver imaging score (FLIS) and spleen diameter predict outcomes in ACLD

BACKGROUND & AIMS

Functional liver imaging score (FLIS) - derived from gadoxetic acid-enhanced MRI - correlates with liver function and independently predicts liver-related mortality in patients with chronic liver disease (CLD), while splenic craniocaudal diameter (SCCD) is a marker of portal hypertension. The aim of this study was to investigate the accuracy of a combination of FLIS and SCCD for predicting hepatic decompensation, acute-on-chronic liver failure (ACLF), and mortality in patients with advanced CLD (ACLD).

METHODS

We included 397 patients with CLD who underwent gadoxetic acid-enhanced liver MRI. The FLIS was calculated by summing the points (0-2) of 3 hepatobiliary-phase features: hepatic enhancement, biliary excretion, and portal vein signal intensity. Patients were stratified into 3 groups according to liver fibrosis severity and presence/history of hepatic decompensation: non-ACLD, compensated ACLD (cACLD), and decompensated ACLD (dACLD).

RESULTS

SCCD showed excellent intra- and inter-reader agreement. Importantly, SCCD was an independent risk factor for hepatic decompensation in patients with cACLD (per cm; adjusted hazard ratio [aHR] 1.13; 95% CI 1.04-1.23; p = 0.004). Patients with cACLD and a FLIS of 0-3 points and/or a SCCD of >13 cm were at increased risk of hepatic decompensation (aHR 3.07; 95% CI 1.43-6.59; p = 0.004). In patients with dACLD, a FLIS of 0-3 was independently associated with an increased risk of ACLF (aHR 2.81; 95% CI 1.16-6.84; p = 0.02), even after adjusting for other prognostic factors. Finally, a FLIS and SCCD-based algorithm was independently predictive of transplant-free mortality and stratified the probability of transplant-free survival (TFS) in ACLD (p <0.001): FLIS 4-6 and SCCD ≤13 cm (5-year TFS of 84%) vs. FLIS 4-6 and SCCD >13 cm (5-year TFS of 70%) vs. FLIS 0-3 (5-year TFS of 24%).

CONCLUSION

The FLIS and SCCD are simple imaging markers that provide complementary information for risk stratification in patients with compensated and decompensated ACLD.

LAY SUMMARY

Magnetic resonance imaging (MRI) can be used to assess the state of the liver. Previously the functional liver imaging score, which is based on MRI criteria, was developed as a measure of liver function and to predict the risk of liver-related complications or death. By combining this score with a measurement of spleen diameter, also using MRI, we generated an algorithm that could predict the risk of adverse liver-related outcomes in patients with advanced chronic liver disease.

Hepatogenous diabetes: Knowledge, evidence, and skepticism

The diabetogenic potential of liver cirrhosis (LC) has been known for a long time, and the name "hepatogenous diabetes" (HD) was coined in 1906 to define the condition. Diabetes mellitus (DM) that develops as a consequence of LC is referred to as HD. In patients with LC, the prevalence rates of HD have been reported to vary from 21% to 57%. The pathophysiological basis of HD seems to involve insulin resistance (IR) and pancreatic β-cell dysfunction. The neurohormonal changes, endotoxemia, and chronic inflammation of LC initially create IR; however, the toxic effects eventually lead to β-cell dysfunction, which marks the transition from impaired glucose tolerance to HD. In addition, a number of factors, including sarcopenia, sarcopenic obesity, gut dysbiosis, and hyperammonemia, have recently been linked to impaired glucose metabolism in LC. DM is associated with complications and poor outcomes in patients with LC, although the individual impact of each type 2 DM and HD is unknown due to a lack of categorization of diabetes in most published research. In fact, there is much skepticism within scientific organizations over the recognition of HD as a separate disease and a consequence of LC. Currently, T2DM and HD are being treated in a similar manner although no standardized guidelines are available. The different pathophysiological basis of HD may have an impact on treatment options. This review article discusses the existence of HD as a distinct entity with high prevalence rates, a strong pathophysiological basis, clinical and therapeutic implications, as well as widespread skepticism and knowledge gaps.

Nomogram for predicting the risk of gastroesophageal varices after primary endoscopic prophylaxis for variceal hemorrhage in patients with cirrhosis

BACKGROUND AND AIMS

The aim of this study was to identify predictors of non-high-risk gastroesophageal varices and evaluate the probability of the residual high-risk varices in cirrhosis patients after the primary endoscopic treatment.

PATIENTS AND METHODS

Medical records of the patients with cirrhosis admitted for primary endoscopic prophylaxis gastroesophageal varices hemorrhage were retrospectively analyzed. The patients were divided into high-risk varices and non-high-risk varices groups according to the endoscopy. A nomogram was developed based on the results of multivariate Cox analyses. Accuracy of this model was validated by the concordance index (Harrell's c-index) and calibration curve.

RESULTS

Altogether 117 patients were enrolled between March 2014 and April 2018. The multivariate Cox analyses identified spleen length <140 mm [odds ratio (OR) = 2.715; P = 0.037), small or medium size of esophageal varices (OR = 4.412; P = 0.017), unaccompanied with gastric varices (OR = 7.025; P = 0.003) and frequency of endoscopic variceal ligation ≥one time per 4 months (OR = 3.834; P = 0.034) as independent factors of non-high-risk varices. All significant predictors were incorporated into a nomogram to predict the residual high-risk varices, which showed a notable accuracy with the concordance index (0.833).

CONCLUSION

The nomogram-based prediction of residual high-risk varices can be used for risk stratification in cirrhosis patients with gastroesophageal varices.

CT-Based Radiomics Score Can Accurately Predict Esophageal Variceal Rebleeding in Cirrhotic Patients

Purpose: This study aimed to develop a radiomics score (Rad-score) extracted from liver and spleen CT images in cirrhotic patients to predict the probability of esophageal variceal rebleeding. Methods: In total, 173 cirrhotic patients were enrolled in this retrospective study. A total of 2,264 radiomics features of the liver and spleen were extracted from CT images. Least absolute shrinkage and selection operator (LASSO) Cox regression was used to select features and generate the Rad-score. Then, the Rad-score was evaluated by the concordance index (C-index), calibration curves, and decision curve analysis (DCA). Kaplan-Meier analysis was used to assess the risk stratification ability of the Rad-score. Results: Rad-score_Liver, Rad-score_Spleen, and Rad-score_Liver-Spleen were independent risk factors for EV rebleeding. The Rad-score_Liver-Spleen, which consisted of ten features, showed good discriminative performance, with C-indexes of 0.853 [95% confidence interval (CI), 0.776-0.904] and 0.822 (95% CI, 0.749-0.875) in the training and validation cohorts, respectively. The calibration curve showed that the predicted probability of rebleeding was very close to the actual probability. DCA verified the usefulness of the Rad-score_Liver-Spleen in clinical practice. The Rad-score_Liver-Spleen showed good performance in stratifying patients into high-, intermediate- and low-risk groups in both the training and validation cohorts. The C-index of the Rad-score_Liver-Spleen in the hepatitis B virus (HBV) cohort was higher than that in the non-HBV cohort. Conclusion: The radiomics score extracted from liver and spleen CT images can predict the risk of esophageal variceal rebleeding and stratify cirrhotic patients accordingly.

Management of portal hypertensive upper gastrointestinal bleeding: Report of the Coorg Consensus workshop of the Indian Society of Gastroenterology Task Force on Upper Gastrointestinal Bleeding

Portal hypertensive bleeding is a major complication of portal hypertension (PHT) with high morbidity and mortality. A lot of advances have been made in our understanding of screening, risk stratification, and management strategies for portal hypertensive bleeding including acute variceal bleeding leading to improved overall outcomes in patients with PHT. A number of guidelines on variceal bleeding have been published by various societies in the past few years. The Indian Society of Gastroenterology (ISG) Task Force on Upper Gastrointestinal Bleeding (UGIB) felt that it was necessary to bring out a standard practice guidance document for the use of Indian health care providers especially physicians, gastroenterologists, and hepatologists. For this purpose, an expert group meeting was convened by the ISG Task Force to deliberate on this matter and write a consensus guidance document for Indian practice. The delegates including gastroenterologists, hepatologists, radiologists, and surgeons from different parts of the country participated in the consensus development meeting at Coorg in 2018. A core group was constituted which reviewed all published literature on portal hypertensive UGIB with special reference to the Indian scenario and prepared unambiguous statements on different aspects for voting and consensus in the whole group. This consensus was produced through a modified Delphi process and reflects our current understanding and recommendations for the diagnosis and management of portal hypertensive UGIB in Indians. Intended for use by the health care providers especially gastroenterologists and hepatologists, these consensus statements provide an evidence-based approach to risk stratification, diagnosis, and management of patients with portal hypertensive bleeding.

Portal vein obstruction after pediatric liver transplantation: A systematic review of current treatment strategies

INTRODUCTION

Portal vein obstruction (PVO) is a significant vascular complication after liver transplantation (LT) in pediatric patients. Current treatment strategies include percutaneous transluminal angioplasty (PTA), with or without stent placement, mesorex bypass (MRB), splenorenal shunt, mesocaval shunt, endovascular recanalization (EVR), splenic artery embolization and splenectomy. However, specific characteristics of patients undergoing intervention and selection of individual treatment and its efficacy have remained unclear. This review systematically analyzed biochemical and clinical characteristics, selection of treatment, efficacy, and post-procedural complications.

METHODS

We systematically searched PubMed and Embase between January 1995 and March 2021 for studies on the management of PVO after LT. We analyzed the reports for biochemical and clinical characteristics at the timing of the intervention in different patients, selection of treatment, and reported efficacies.

RESULTS

We found 22 cohort studies with 362 patients who had the following characteristics: biliary atresia (83%), living-donor LT (85%), thrombocytopenia (73%), splenomegaly (40%), ascites (16%), or gastrointestinal bleeding (26%). The 3-year primary patency of PTA without stent placement was similar to that with stent placement (70%-80% and 43%-94%, respectively). MRB was used as an initial treatment with a 3-year patency of 75% to 100%. One study showed that 5-year primary patency of EVR was 80%. Secondary patency was 90% to 100% after 3 years in all studies with PTA alone, PTA/stent placement, and stent placement alone.

CONCLUSION

This is the first review of all treatment protocols in PVO after pediatric LT. We showed that an important group of patients has severe symptoms of portal hypertension. Efficacy of all treatment modalities was high in the included studies which make them important modalities for these patients.

Modulation of vascular contraction via soluble guanylate cyclase signaling in a novel ex vivo method using rat precision-cut liver slices

Fibrotic processes in the liver of non-alcoholic steatohepatitis (NASH) patients cause microcirculatory dysfunction in the organ which increases blood vessel resistance and causes portal hypertension. Assessing blood vessel function in the liver is challenging, necessitating the development of novel methods in normal and fibrotic tissue that allow for drug screening and translation toward pre-clinical settings. Cultures of precision cut liver slices (PCLS) from normal and fibrotic rat livers were used for blood vessel function analysis. Live recording of vessel diameter was used to assess the response to endothelin-1, serotonin and soluble guanylate cyclase (sGC) activation. A cascade of contraction and relaxation events in response to serotonin, endothelin-1, Ketanserin and sGC activity could be established using vessel diameter analysis of rat PCLS. Both the sGC activator BI 703704 and the sGC stimulator Riociguat prevented serotonin-induced contraction in PCLS from naive rats. By contrast, PCLS cultures from the rat CCl4 NASH model were only responsive to the sGC activator, thus establishing that the sGC enzyme is rendered non-responsive to nitric oxide under oxidative stress found in fibrotic livers. The role of the sGC pathway for vessel relaxation of fibrotic liver tissue was identified in our model. The obtained data shows that the inhibitory capacities on vessel contraction of sGC compounds can be translated to published preclinical data. Altogether, this novel ex vivo PCLS method allows for the differentiation of drug candidates and the translation of therapeutic approaches towards the clinical use.

Analogies and differences between cirrhotic cardiomyopathy and hepatopulmonary syndrome

Cirrhotic cardiomyopathy and hepatopulmonary syndrome are two quite frequent clinical entities that may complicate the course of liver cirrhosis. The common pathophysiological origin and the same clinical presentation make them difficult to compare. Cirrhotic cardiomyopathy and hepatopulmonary syndrome may start with dyspnea and breathlessness but the former is characterized by a chronic cardiac dysfunction and the latter by a defect of oxygenation due to pulmonary shunts formation. The focus is to differentiate them as soon as possible since the treatment is different until the patient undergoes liver transplant that is the real unique cure for them.

Non-invasive prediction model for high-risk esophageal varices in the Chinese population

BACKGROUND

There are two types of esophageal varices (EVs): high-risk EVs (HEVs) and low-risk EVs, and HEVs pose a greater threat to patient life than low-risk EVs. The diagnosis of EVs is mainly conducted by gastroscopy, which can cause discomfort to patients, or by non-invasive prediction models. A number of non-invasive models for predicting EVs have been reported; however, those that are based on the formula for calculation of liver and spleen volume in HEVs have not been reported.

AIM

To establish a non-invasive prediction model based on the formula for liver and spleen volume for predicting HEVs in patients with viral cirrhosis.

METHODS

Data from 86 EV patients with viral cirrhosis were collected. Actual liver and spleen volumes of the patients were determined by computed tomography, and their calculated liver and spleen volumes were calculated by standard formulas. Other imaging and biochemical data were determined. The impact of each parameter on HEVs was analyzed by univariate and multivariate analyses, the data from which were employed to establish a non-invasive prediction model. Then the established prediction model was compared with other previous prediction models. Finally, the discriminating ability, calibration ability, and clinical efficacy of the new model was verified in both the modeling group and the external validation group.

RESULTS

Data from univariate and multivariate analyses indicated that the liver-spleen volume ratio, spleen volume change rate, and aspartate aminotransferase were correlated with HEVs. These indexes were successfully used to establish the non-invasive prediction model. The comparison of the models showed that the established model could better predict HEVs compared with previous models. The discriminating ability, calibration ability, and clinical efficacy of the new model were affirmed.

CONCLUSION

The non-invasive prediction model for predicting HEVs in patients with viral cirrhosis was successfully established. The new model is reliable for predicting HEVs and has clinical applicability.

Risk assessment of first upper gastrointestinal bleeding using computerized tomoscanning in esophageal varices patients with cirrhosis and portal hypertension

To evaluate the risk of first upper gastrointestinal bleeding by computerized tomoscanning (CT) for esophageal varices patients with cirrhotic portal hypertension.One hundred thirty two esophageal varices patients with cirrhotic portal hypertension who are also complicated with gastrointestinal bleeding were recruited as bleeding group, while another 132 patients without bleeding as non-bleeding group. The diameter of esophageal varices, number of vascular sections, and total area of blood vessels were measured by CT scanning. The sensitivity and specificity of these indicators were calculated, and Youden index was adjusted with the critical point.The diameter of esophageal varices was 7.83 ± 2.76 mm in bleeding group, and 6.57 ± 3.42 mm in non-bleeding group. The Youden index was 0.32 with the critical point 5.55 mm. The area under the receiver operating characteristics (AUROC) was 0.72. The number of venous vessels was 4.5 ± 2 in bleeding group, whereas being 4 ± 2 in non-bleeding group. The Youden index was 0.35 with a critical point 4, and the area under the curve (AUC) was 0.68. The blood vessel area was 1.73 ± 1.15 cm in bleeding group, and 1.12 ± 0.89 cm in non-bleeding group. The Youden index was 0.48 with the critical point being 1.03 cm, and corresponding AUC was 0.82.Among all 3 indicators of the total area, diameter, and number of sections of the esophageal varices, the total area of esophageal varices showed more accuracy as a potential and novel indicator for bleeding prediction.

Fibroscan Reliably Rules Out Advanced Liver Fibrosis and Significant Portal Hypertension in Alcoholic Patients

BACKGROUND/GOALS

To date, there is no consensus on optimal cut-off values and timing of transient elastography (TE, Fibroscan) for fibrosis staging and prediction of portal hypertension in alcoholic liver disease. We evaluated the accuracy of Fibroscan for the diagnosis of fibrosis and clinically significant portal hypertension in alcoholic patients.

STUDY

Heavy drinkers admitted to our standardized alcohol withdrawal program were evaluated by Fibroscan, by transjugular hepatic venous pressure gradient (HVPG) measurement and liver biopsy if significant fibrosis was suspected and by upper gastrointestinal endoscopy. All investigations were performed within 3 days of admission. Patients who had remained abstinent for 2 weeks underwent a second Fibroscan.

RESULTS

A total of 118 patients were included. Fibroscan correlated well with histology and HVPG. Negative predictive value of 92% and 93% for ruling out severe fibrosis (≥F3) and cirrhosis, and optimal cut-offs at ≥11.7, ≥15.2, and ≥21.2 kPa for F2, F3, and F4, respectively, were found. In abstinent patients, a mean decrease of 2.7 kPa improved concordance between Fibroscan and histology. A TE value of 30.6 kPa predicted a HVPG>10 mm Hg with 94% specificity and showed a good negative predictive value of 84% for ruling out the presence of varices at endoscopy. Steatosis, alcoholic hepatitis, sinusoidal fibrosis, cholestasis, and high transaminases did not influence TE values.

CONCLUSIONS

Fibroscan is an accurate non-invasive method for the diagnosis of fibrosis in alcoholic patients. TE values below 11 and 30 kPa likely rule out significant fibrosis and varices, respectively.

Electronic health record year and country of birth testing and patient navigation to increase diagnosis of chronic viral hepatitis

The United States Preventive Services Task Force recommends hepatitis C testing people born from 1945 to 1965, "birth cohort" as well as hepatitis C and hepatitis B testing people from countries of birth with endemic infection risk. We automated the hospital electronic health record system to test birth cohort and those born in countries with endemic infection risk. A script is launched searching the laboratory database upon registration for any hepatitis C antibody, hepatitis C RNA and/or hepatitis B surface antigen result. If no positive result was found, a hepatitis C antibody/reflex RNA and/or hepatitis B surface antigen were ordered. A patient navigator received weekly results and assisted patients with positive serology to schedule an appointment with their primary care provider or treatment specialist. A total of 10 726 participants were hepatitis C antibody tested, with 6.9% antibody positive. Monthly hepatitis C testing from January to July 2016 compared to August 2016-August 2017 increased 342% as a result of "birth cohort" testing. Following country of birth testing, monthly hepatitis B and hepatitis C testing increased 91%, and 44%, respectively, during June-August 2017 compared to September 2017-March 2018. 67% of hepatitis C-positive patients were linked to care. If the navigator contacted the patient, 92% were linked to care, and 32% were treated. Of hepatitis B surface antigen-positive patients, 43% were linked to care, 5% were on treatment, and 15% started treatment. Automated electronic health record ordering of hepatitis C and/or hepatitis B testing is feasible and increases testing. In the population tested, much improvement is needed with linkage to care and treatment.

Five-year-term results in cirrhotics without varices, either affected or not by portal hypertensive gastropathy

OBJECTIVES

Information is lacking on the appearance of varices in cirrhotics, either affected or not by portal hypertensive gastropathy (PHG). We assessed whether the absence or presence and the grade of PHG influenced the development of varices in cirrhotics without varices over time.

PATIENTS AND METHODS

Forty cirrhotics without varices affected or not by PHG at baseline underwent follow-up endoscopy after 5 years. One-tailed t-test and the χ-test were used to evaluate variable comparison and the presence of associations. Multivariate logistic regression analysis and the analysis of variance test were carried out to compare the variables and identify predictors of varices.

RESULTS

The Child-Pugh score at baseline and after 5 years was significantly different (5.72±0.98 vs. 6.25±1.67, P<0.001). After 5 years, 10 (25%) cirrhotics were affected by varices, whereas 30 (75%) patients remained without varices. PHG was associated significantly with varices (P=0.001), proving to be a significant predictive independent factor for their development over time (F=4.765, significant=0.004; analysis of variance test, P<0.001).

CONCLUSION

A link between the duration of PHG and the development of varices is likely. An early therapeutic management of PHG might delay the development of varices in cirrhotics.

Hemodynamic measurements with an abdominal 4D flow MRI sequence with spiral sampling and compressed sensing in patients with chronic liver disease

BACKGROUND

The test-retest/interobserver repeatability and diagnostic value of 4D flow MRI in liver disease is underreported.

PURPOSE

To determine the reproducibility/repeatability of flow quantification in abdominal vessels using a spiral 4D flow MRI sequence; to assess the value of 4D flow parameters in diagnosing cirrhosis and degree of portal hypertension.

STUDY TYPE

Prospective.

SUBJECTS

Fifty-two patients with chronic liver disease.

FIELD STRENGTH/SEQUENCE

1.5T/spiral 4D flow acquired in one breath-hold.

ASSESSMENT

Thirteen abdominal vessels were identified and segmented by two independent observers to measure maximum and time-averaged through-plane velocity, net flow, and vessel cross-section area. Interobserver agreement and test-retest repeatability were evaluated in 15 and 4 cases, respectively. Prediction of the presence and severity of cirrhosis and portal hypertension was assessed using 4D flow parameters.

STATISTICAL TESTS

Cohen's kappa coefficient, coefficient of variation (CV), Bland-Altman, Mann-Whitney tests, logistic regression.

RESULTS

For all vessels combined, measurements showed acceptable agreement between observers, with Cohen's kappa = 0.70 (P < 0.001), CV < 21%, Bland-Altman bias <5%, but high limits of agreement ([-75%,75%]). Test-retest repeatability was excellent in large vessels (CV = 1-15%, bias = 1-25%, Bland-Altman limits of agreement [BALA] = [4%,150%]), and poor in small vessels (CV = 7-130%, bias = 10-200%, BALA = [8%,190%]). Average velocity in the right hepatic vein and average area of the splenic vein were higher in cirrhosis (P = 0.027/0.0039). Flow in the middle hepatic vein strongly correlated with Child-Pugh score (ρ = 0.84, P = 0.0238), while flow in the splenic vein (ρ = 0.43, P = 0.032), time-average (ρ = 0.46, P = 0.02) and peak velocity in the superior mesenteric vein (ρ = 0.45, P = 0.032), and peak velocity in the infrarenal IVC (ρ = 0.39, P = 0.032) positively correlated with an imaging-based portal hypertension score. Average area of the splenic vein predicted cirrhosis (P = 0.019; area under the curve AUC [95% confidence interval, CI] = 0.87 [0.71,1.00]) and clinically significant portal hypertension (P = 0.042; AUC [95% CI] = 0.78 [0.57-0.99]).

DATA CONCLUSION

Spiral 4D flow allows comprehensive assessment of abdominal vessels in one breath-hold, with substantial interobserver reproducibility, but variable test-retest repeatability. 4D flow may potentially reflect vascular changes due to cirrhosis and portal hypertension.

LEVEL OF EVIDENCE

2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:994-1005.

Invasive Hemodynamic Characterization of the Portal-hypertensive Syndrome in Cirrhotic Rats

This is a detailed protocol describing invasive hemodynamic measurements in cirrhotic rats for the characterization of portal hypertensive syndrome. Portal hypertension (PHT) due to cirrhosis is responsible for the most severe complications in patients with liver disease. The full picture of the portal hypertensive syndrome is characterized by increased portal pressure (PP) due to the increased intrahepatic vascular resistance (IHVR), hyperdynamic circulation, and increased splanchnic blood flow. Progressive splanchnic arterial vasodilation and increased cardiac output with elevated heart rate (HR) but low arterial pressure characterizes the portal hypertensive syndrome. Novel therapies are currently being developed that aim to decrease PP by either targeting IHVR or increased splanchnic blood flow - but side effects on systemic hemodynamics may occur. Thus, a detailed characterization of portal venous, splanchnic, and systemic hemodynamic parameters, including measurement of PP, portal venous blood flow (PVBF), mesenteric arterial blood flow, mean arterial pressure (MAP), and HR is needed for preclinical evaluation of the efficacy of novel treatments for PHT. Our video article provides the reader with a structured protocol for performing invasive hemodynamic measurements in cirrhotic rats. In particular, we describe the catheterization of the femoral artery and the portal vein via an ileocolic vein and the measurement of portal venous and splanchnic blood flow via perivascular Doppler-ultrasound flow probes. Representative results of different rat models of PHT are shown.

Portopulmonary hypertension and hepatorenal syndrome. Two faces of the same coin

Portopulmonary hypertension and hepatorenal syndrome are both severe local hypertensive complications of liver cirrhosis and portal hypertension. Both are characterized by vasoconstrictive manifestations regarding pulmonary and renal vascular network, respectively. This review addresses the mechanisms underlying the development of vasoconstriction that leads to local vascular hypertension in the lung and in the kidney with the result of organ dysfunction. Potential therapeutic options are available for the management of these two syndromes as a bridge for liver transplantation; clinical efficacy depends in part on the time and rapidity of intervention and in part on how serious the chain of events is that has triggered the entire vasoconstrictive process.

Phase-contrast MR flow imaging: A tool to determine hepatic hemodynamics in rats with a healthy, fibrotic, or cirrhotic liver

PURPOSE

To test a magnetic resonance (MR) scanning protocol as a noninvasive tool to determine hepatic hemodynamics and to assess the degree of liver fibrosis in an animal model of liver fibrosis and cirrhosis.

MATERIALS AND METHODS

Fifty-four male Wistar rats were studied. Thirty-nine received thioacetamide (TAA) in their drinking water for either 12 or 16 weeks. MR measurements were performed using flow-sensitive 2D phase-contrast MRI and a 9.4T preclinical scanner. The following hemodynamic parameters were investigated: portal cross-sectional area, mean portal flow velocity, and portal and aortic flow volume rate. Therefore, rats (n = 46) were divided into three groups: CON (control, n = 13), FIB (fibrosis, n = 25), and CIR (cirrhosis, n = 8). Furthermore, the degree of liver fibrosis was assessed by a self-established MR score and verified by a standardized histological score (n = 48).

RESULTS

Portal and aortic flow parameters could be reliably detected. A significant decrease in portal flow velocity was found in FIB (FIB vs. CON: -21%, P = 0.006 and CIR vs. CON: -17%, P = 0.105) and in portal flow volume rate in FIB and CIR (FIB vs. CON: -20%, P = 0.009 and CIR vs. CON: -25%, P = 0.024). If the histological score is taken as standard, the self-established MR score enabled discrimination between healthy and diseased livers (sensitivity to identify diseased livers: 89% and specificity to identify healthy livers: 100%).

CONCLUSION

This MR scanning protocol presents a noninvasive tool to determine hepatic hemodynamics in healthy and diseased rats.

LEVEL OF EVIDENCE

2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2017;46:1526-1534.

Clinical role of non-invasive assessment of portal hypertension

Measurement of portal pressure is pivotal in the evaluation of patients with liver cirrhosis. The measurement of the hepatic venous pressure gradient represents the reference method by which portal pressure is estimated. However, it is an invasive procedure that requires significant hospital resources, including experienced staff, and is associated with considerable cost. Non-invasive methods that can be reliably used to estimate the presence and the degree of portal hypertension are urgently needed in clinical practice. Biochemical and morphological parameters have been proposed for this purpose, but have shown disappointing results overall. Splanchnic Doppler ultrasonography and the analysis of microbubble contrast agent kinetics with contrast-enhanced ultrasonography have shown better accuracy for the evaluation of patients with portal hypertension. A key advancement in the non-invasive evaluation of portal hypertension has been the introduction in clinical practice of methods able to measure stiffness in the liver, as well as stiffness/congestion in the spleen. According to the data published to date, it appears to be possible to rule out clinically significant portal hypertension in patients with cirrhosis (i.e., hepatic venous pressure gradient ≥ 10 mmHg) with a level of clinically-acceptable accuracy by combining measurements of liver stiffness and spleen stiffness along with Doppler ultrasound evaluation. It is probable that the combination of these methods may also allow for the identification of patients with the most serious degree of portal hypertension, and ongoing research is helping to ensure progress in this field.

Prediction of esophageal varices in cirrhotic patients with apparent diffusion coefficient of the spleen

PURPOSE

To predict esophageal varices in cirrhotic patients with apparent diffusion coefficient (ADC) of the spleen and to correlate the ADC with clinical and laboratory biomarkers of esophageal varices.

MATERIALS AND METHODS

This study was conducted upon 40 patients (28 male, 12 female; age ranged 19-45 years; mean age = 33 years) with biopsy-proven cirrhotic liver. Twenty age- and sex-matched healthy volunteers were included as a control group. Patients with varices (n = 15) and without varices (n = 25) and volunteers underwent echo-planar diffusion-weighted MR imaging of the abdomen with b factors of 0, 400, and 800 s/mm(2). The ADC maps of the abdomen were reconstructed. The ADC values of the spleen were calculated and correlated with the Child score, platelet count, and prothrombin time.

RESULTS

The mean ADC value of the spleen in cirrhotic patients (1.34 ± 0.05 × 10(-3) mm(2)/s) was significantly different (P = 0.001) from that of volunteers (0.87 ± 0.04 × 10(-3) mm(2)/s). The ADC of the spleen in cirrhotic patients with varices (1.49 ± 0.05 × 10(-3) mm(2)/s) was significantly different (P = 0.001) from that of patients without varices (1.11 ± 0.06 × 10(-3) mm(2)/s). The cut-off ADC value of the spleen used for prediction of cirrhosis and varices was 1.15 and 1.29 × 10(-3) mm(2)/s with areas under the curve were 0.872 and 0.889, respectively. The ADC value of the spleen was correlated with the splenic volume (r = 0.862; P = 0.001), Child score (r = 0.742; P = 0.001), platelet count (r = -0.698; P = 0.01), and prothrombin time (r = 0.684; P = 0.01).

CONCLUSION

The ADC value of the spleen can predict esophageal varices in cirrhotic patients and is well correlated with the clinical and laboratory biomarkers of esophageal varices.

Quantitative fibrosis estimation by image analysis predicts development of decompensation, composite events and defines event-free survival in chronic hepatitis B patients

The extent of fibrosis is a major determinant of the clinical outcome in patients with chronic liver diseases. We undertook this study to explore the degree of fibrosis in baseline liver biopsies to predict clinical outcomes in chronic hepatitis B (CHB) patients. Fibrosis quantification was done by image analysis on Masson's trichrome-stained sections and correlated with clinical and biochemical parameters, liver stiffness and hepatic vein pressure gradient (n = 96). Follow-up information collected related to clinical outcome. A total of 964 cases was analyzed. Median quantitative fibrosis (QF) was 3.7% (interquartile range, 1.6%-9.7%) with substantial variation in various stages. Median QF was F0, 1% (0.7%-1.65%); F1, 3.03% (2.07%-4.0%); F2, 7.1% (5.6%-8.7%); F3, 12.7% (10.15%-16.7%); F4, 26.9% (20.3%-36.4%). QF positively correlated with METAVIR staging, liver stiffness measurement, and hepatic vein pressure gradient. Eighty-nine cases developed liver-related events: decompensation, hepatocellular carcinoma, liver transplantation and death. Cox regression analysis after adjusting for METAVIR staging-QF, albumin, and AST for composite events; QF and albumin for decompensation; and only QF for hepatocellular carcinoma-were found to be significant predictors of clinical outcomes. QF categorized into five stages: QF1, 0%-5%; QF2, 5.1%-10%; QF3, 10.1%-15%; QF4, 15.1%-20%; QF5, >20.1%. In patients with advanced stages of QF, probability of event-free survival found to be low. Quantitative fibrosis in baseline liver biopsy predicts progression of the disease and disease outcome in CHB patients. QF defines the probability of event-free survival in CHB cases.

A non-invasive magnetic resonance imaging-based model predicts portal venous pressure

OBJECTIVE

To establish a non-invasive model for the assessment of portal venous pressure (PVP) based on the magnetic resonance (MR) parameters.

METHODS

In this prospective study, contrast-enhanced magnetic resonance imaging (MRI) scan was performed in 109 patients indicated for upper abdominal surgeries after their written consents were obtained, and intraoperative PVP measurements were completed in 92 patients. Altogether 17 patients were excluded for not undergoing surgery or unsuccessful catheterization. A linear model was constructed for estimating PVP levels in 56 patients and further validation was conducted in the other 36 patients.

RESULTS

The PVP levels were significantly correlated with MR parameters, including splenic volume (SV), splenic venous diameter (SVD), liver/splenic volume ratio, portal venous diameter, hepatic diameter, portal venous cross-sectional area, ascites, varices and arterial portal shunts. A linear model was established as follows: PVP (mmHg) = 2.529 + 1.572 × SVD (mm) + 0.231 × SV/body mass index (× 10(4) cm(5) /kg) + 3.44 × aspartate aminotransferase-to-platelet ratio index. This model showed excellent accuracy in the detection of portal hypertension, with the area under the receiver operating characteristic curve (AUROC) of 0.945 (95% CI 0.867-1.000), with the sensitivity and specificity of 91.7% and 93.7%, respectively. The agreement analysis revealed that the predictive value using this formula closely reflected the patients' actual PVP level. Moreover, the validation confirmed the accuracy of this model for the assessment of portal hypertension [AUROC 0.935 (95% CI 0.856-1.000)].

CONCLUSIONS

The MRI-based formula has great potential for detecting portal hypertension. As a non-invasive measurement, it may be clinically accepted for the replacement of invasive modalities after further refinement.

Screening and Prophylaxis for Varices in Children with Liver Disease

Esophageal varices in children with portal hypertension are quite common. Bleeding from these varices frequently occurs. Prophylactic measures to prevent such bleeding can be undertaken either before ("primary," prompted by a screening endoscopy) or after ("secondary") an initial variceal bleed. There are no clear pediatric guidelines for primary or secondary prophylaxis of esophageal varices. Adult studies clearly support the use of pharmacologic (beta blockers) and endoscopic (endoscopic band ligation, EBL) management for both primary and secondary prophylaxis of esophageal varices in patients with portal hypertension. Pediatric studies are limited. There are inadequate data to recommend use of beta blockers to prevent variceal bleeding or rebleeding in children with portal hypertension. There is very limited support for EBL for primary prophylaxis in children and more compelling support for EBL for secondary prophylaxis. Further randomized controlled studies are needed but are difficult to implement in this vulnerable population.

Cirrhotic cardiomyopathy in the pre- and post-liver transplantation phase

Patients with advanced liver cirrhosis may develop a clinical syndrome characterized by a blunted contractile responsiveness to stress and/or altered diastolic relaxation, called "cirrhotic cardiomyopathy." This syndrome, which is initially asymptomatic, is often misdiagnosed due to the presence of symptoms that characterize other disorders present in patients with advanced liver cirrhosis, such as exercise intolerance, fatigue, and dyspnea. Stress and other conditions such as liver transplantation and transjugular intrahepatic portosystemic shunt (TIPS) may unmask this syndrome. Liver transplantation in this group of patients results in a clinical improvement and can be a cure for the cardiomyopathy. However, post-transplant prognosis depends on the identification of cirrhotics with cardiomyopathy in the pre-transplant phase; an early diagnosis of cirrhotic cardiomyopathy in the pre-transplant phase may avoid an acute onset or worsening of cardiac failure after liver transplantation. Since a preserved left ventricular ejection fraction may mask the presence of cirrhotic cardiomyopathy, the use of newer noninvasive diagnostic techniques (i.e. tissue Doppler, myocardial strain) is necessary to identify cirrhotics with this syndrome, in the pre-transplant phase. A pre-transplant treatment of heart failure in cirrhotics with cardiomyopathy improves the quality of life in this phase and reduces the complications during and immediately after liver transplantation. Since specific therapies for cirrhotic cardiomyopathy are lacking, due to the absence of a clear understanding of the pathophysiology of the cardiomyopathy, further research in this field is required.

Portal hypertensive gastropathy in cirrhotics without varices: a case-control study

OBJECTIVE

Information is lacking on portal hypertensive gastropathy (PHG) in cirrhotics without varices; our aim it is to evaluate whether clinical and sonographic parameters are associated with PHG and may provide information suitable for the management of these patients.

PATIENTS AND METHODS

After endoscopic selection of 145 cirrhotics without varices, 75 with PHG and 70 without PHG, clinical and sonographic characteristics were assessed.

RESULTS

Forty portosystemic shunts were present in 27 patients. The mean Child-Pugh score was 6.3±1.4 and 5.6±0.5 in patients with severe and mild PHG, respectively (P=0.004). The mean portal vein diameter was 10.4±1.7 and 11.6±2.0 mm in cirrhotics without and with PHG, respectively (P=0.0002).

CONCLUSION

A link between the presence of PHG and a more advanced phase of cirrhosis was found. Duplex Doppler sonography was confirmed to be a valuable diagnostic method in monitoring cirrhosis. Management of these patients cannot be performed on the basis of a single diagnostic method, and a multimodal diagnostic approach is required.