Correlation of transient elastography with hepatic venous pressure gradient in patients with cirrhotic portal hypertension: A study of 326 patients from India

Etiological Spectrum of Cirrhosis in India: A Systematic Review and Meta-analysis

BACKGROUND

Cirrhosis is a significant cause of morbidity and mortality globally and in India. This systematic review and meta-analysis aimed to ascertain the etiological spectrum and changing trends of cirrhosis in India.

METHODS

We searched electronic databases, including Pubmed/Medline, Scopus, and Embase. We included original studies that reported the etiology of cirrhosis in the Indian population.

RESULTS

We included 158 studies (adults: 147, children: 11). The overall pooled estimate of alcohol as a cause of cirrhosis in adults was 43.2% (95% confidence interval (CI) 39.8-46.6%; I2 = 97.8%), followed by nonalcoholic fatty liver disease (NAFLD)/cryptogenic in 14.4%, 95% CI (11.7-17.3%; I2 = 98.4%), hepatitis B virus (HBV) in 11.5%, 95% CI (9.8-13.3%; I2 = 96.6%), and hepatitis C virus (HCV) in 6.2%, 95% CI (4.8-7.8%; I2 = 97.2%) of the included patients. The most common cause of cirrhosis in all zones was alcohol-related. Comparison of etiologies over time revealed a reduction in the viral hepatitis-related and an increase in the proportion of alcohol-related and NAFLD/cryptogenic-related cirrhosis. The overall pooled estimates of various etiologies in children were: HBV in 10.7%, 95% CI (4.6-18.7%; I2 = 91.0%), NAFLD/Cryptogenic in 22.3%, 95% CI (9.0-39.2%; I2 = 96.7%), and HCV in 2.0%, 95% CI (0.0-8.5%; I2 = 94.6%).

CONCLUSIONS

Alcohol is the most common etiology of cirrhosis in adults in India. The proportions of alcohol and NAFLD-related cirrhosis are increasing, and those of viral hepatitis-related cirrhosis are reducing. The results of our meta-analysis will help formulate health policies and the allocation of resources.

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.

Performance of spleen stiffness measurement by 2D-shear wave elastography in evaluating the presence of high-risk varices: comparative analysis of idiopathic portal hypertension versus hepatitis B virus

BACKGROUND

Noninvasive assessment of high-risk varices (HRV) in idiopathic portal hypertension (IPH) is rare. The purpose of this study was to investigate the performance of spleen stiffness (SS) for evaluating the presence of HRV in IPH patients as compared the measurements in patients with hepatitis B virus (HBV).

METHODS

A retrospective single-center study was performed to evaluate the performance of SS for assessing HRV in IPH and HBV-infected patients, in comparison with liver stiffness (LS), spleen stiffness-to-liver stiffness ratio (SS/LS), LS spleen-diameter-to-platelet-ratio score (LSPS), portal hypertension risk score (PH risk score) and varices risk score, by using upper gastrointestinal endoscopy (UGE) as the gold standard. Finally, 86 IPH and 102 HBV-infected patients were enrolled. UGE, two-dimensional shear wave elastography (2D-SWE) and laboratory data were collected, and noninvasive parameters were calculated. Analysis of receiver operating characteristic (ROC) curves was conducted to acquire the optimal area under the ROC curve (AUC) and cutoff value for predicting the presence of HRV.

RESULTS

In patients with HRV, the significantly different parameters between IPH (34.9%) and HBV-infected patients (46.1%) were as follows: spleen size (diameter 18.5 ± 3.9 cm vs. 20.8 ± 2.7 cm), SS (50.2 kPa vs. 42.9 kPa), LS (11.1 kPa vs. 18.3 kPa) and PT (prothrombin time 15.1 s vs. 16.7 s). No statistically significant differences were found in liver function, platelet counts, spleen thickness and flow volumes in the portal venous system (p > 0.05). The AUCs of SS were 0.98 and 0.96 for predicting the presence of HRV in IPH (44.0 kPa cutoff value; 0.93 sensitivity; 0.96 specificity) and HBV-infected patients (35.2 kPa cutoff value; 1.00 sensitivity; 0.82 specificity), respectively, which were significantly better than other parameters.

CONCLUSION

SS shows the optimal overall performance for predicting the presence of HRV in IPH and HBV-infected patients, in comparison with other noninvasive parameters.

Spleen stiffness can predict liver decompensation and survival in patients with cirrhosis

BACKGROUND AND AIM

Liver stiffness measurement (LSM) has been predicting liver decompensation and survival in cirrhotics. The aim of our study was to investigate if spleen stiffness measurement (SSM) by 2D shear-wave elastography could predict better the probability of decompensation and mortality, compared with LSM and other parameters.

METHODS

Consecutive cirrhotic patients were recruited between 1/2017 and 12/2021. LSM and SSM were performed at baseline and epidemiological, clinical, and laboratory data were collected. Clinical events were recorded every 3 months.

RESULTS

Totally, 177 patients were followed for a mean period of 31 ± 18 months. In Cox regression analysis, only SSM was independently associated with the probability of decompensation (HR: 1.063, 95% CI: 1.009-1.120; P = 0.021), offering an AUROC of 0.710 (P = 0.003) for predicting 1-year liver decompensation (NPV: 81.1% for the cut-off point of 37 kPa). The occurrence of death/liver transplantation was independently associated only with higher SSM (HR: 1.043; 95% CI:1.003-1.084; P = 0.034). The AUROC of SSM for predicting 1-year death/liver transplantation was 0.72 (P = 0.006) (NPV: 95% for the cut-off of 38.8 kPa). The performance of SSM to predict the 1-year death/liver transplantation increased in high-risk patients (CTP: B/C plus MELD >10 plus LSM > 20 kPa), giving an AUROC of 0.80 (P < 0.001). Only 1/26 high-risk patients with SSM < 38.8 kPa died during the first year of follow-up (NPV: 96.4%).

CONCLUSIONS

SSM was the only factor independently associated with the probability of decompensation and occurrence of death, showing better diagnostic accuracy for the prediction of 1-year decompensation or death compared with LSM and MELD score.

Spleen stiffness: a predictive factor of dismal prognosis in liver cirrhosis

Portal hypertension (PH) is a major complication of liver cirrhosis, as it predisposes to the development of serious clinical manifestations such as ascites, hepatic encephalopathy and variceal bleeding, aggravating the prognosis of patients. Hepatic vein pressure gradient (HVPG) is considered the reference method for the estimation of the presence and severity of PH, but this procedure is available only in specialized centers. Alternatively, many non-invasive methods have been proposed in order to substitute HVPG. Among them, liver stiffness measurement (LSM) has been widely used, as it has been shown to correlate well with HVPG, though this relationship seems to weaken in values of HVPG higher than 12 mmHg, the threshold of serious complications development. Several studies supported the use of spleen stiffness measurement (SSM) instead of LSM, anticipating to a more adequate assessment of this advanced stage of PH. The aim of this paper is to critically appraise and summarize the literature about the role of SSM as a predictive tool of liver decompensation and prognosis, highlighting the strengths and the potential limitations of the studies published so far. EXPERT'S OPINION: The utility of SSM in ruling out high risk for bleeding varices in cirrhotic patients has been demonstrated, driving the Baveno VII consensus to encompass SSM in its last recommendations, though its use in patients with non-viral cirrhosis remains to be validated. We believe that in the near future, SSM alone or combined with other tests, will being used not only for sparing upper endoscopies, but also for predicting decompensation and prognosis in advanced compensated cirrhotic patients, regardless of liver disease's etiology. Herein, we present the data that support this consideration, pointing out these issues that should further be investigated in order to elucidate and intensify the value of SSM in the management of patients with liver cirrhosis.

Limited diagnostic value of liver stiffness for clinically significant portal hypertension in HBV-related cirrhosis

PURPOSE

Hepatic venous pressure gradient (HVPG) is the gold standard for portal pressure in cirrhosis, but most previous studies focused on the diagnostic value of clinically significant portal hypertension (CSPH) based on the correlation between liver stiffness (LS) and HVPG in hepatitis C virus (HCV) patients and alcoholic liver. Therefore, it is necessary to clarify the diagnostic value of LS for CSPH and the correlation with HVPG in hepatitis B virus (HBV) patients.

METHODS

A total of 137 patients from the Fifth Medical Center of PLA General Hospital were divided into HBV group and non-HBV group according to etiology. Correlation analysis and ROC were used to analyze the correlation between LS and HVPG and the diagnostic value of CSPH.

RESULTS

There was a good correlation between LS and HVPG in the total cohort and non-HBV cohort (r = 0.398, P < 0.001; r = 0.575, P < 0.001, respectively). However, the correlation between LS and HVPG was acceptable in the HBV cohort (r = 0.316, P = 0.002). When adjustment for age, MELD score, and INR, the result was still the same. Similar results were observed in the prediction for CSPH. LS showed good diagnostic value for CSPH in the total cohort and non-HBV cohort (AUC = 0.732, AUC = 0.829, respectively). However, it performed poorly in the HBV cohort (AUC = 0.689).

CONCLUSION

The etiology of HBV might affect the diagnostic performance of LS for predicting CSPH.

Hepatic venous pressure gradient (HVPG) predicts liver failure after transjugular intrahepatic portal shunt: a retrospective cohort study

BACKGROUND

Esophagogastric variceal bleeding is a serious complication of decompensated cirrhosis. Transjugular intrahepatic portal shunt (TIPS) is a salvage treatment with clear hemostatic results. However, various complications may occur after TIPS, including postoperative liver failure, and the prognosis is very poor once occurs. Liver failure is a common symptom of severe liver disease with a high mortality rate. This study investigated the incidence of liver failure after TIPS treatment for varicose bleeding.

METHODS

We analyzed the data of patients admitted to the First Affiliated Hospital of Soochow University between January 2013 and December 2018 with portal hypertension with an episode of acute gastroesophageal variceal bleeding. A total of 121 patients were referred to the regional liver unit for TIPS. Hepatic venous pressure gradient (HVPG) and clinical data were collected. Patients with incomplete data were excluded, and 93 patients were ultimately enrolled in the study. Primary outcomes were morbidity and hospital mortality within 4 weeks of surgery. The data were retrospectively and consecutively collected and evaluated by univariate and multivariate analyses to identify risk factors of liver failure.

RESULTS

The patients included 58 males (62.37%) and 35 females (37.63%), and the mean age was 58.43±11.85 years. The main cause was hepatitis B virus (HBV), which was found in 50.54% of patient. The overall surgical success rate was 83.87% (78/93). Of 15 treatment-failure patients, 9 (9.68%) died in hospital. Four patients died of liver failure, accounting for 44.44% of postoperative all-cause deaths. Univariate logistic regression analysis showed that only hepatic venous pressure gradient (HVPG) was an independent risk factor for post-TIPS morbidity [relative risk (RR) 1.156; 95% confidence interval (CI): 1.041 to 1.283; P=0.006]. In addition, HVPG was an independent risk factor for hospital mortality within 4 weeks (RR 1.133; 95% CI: 1.021 to 0.539; P=0.016).

CONCLUSIONS

Post-TIPS liver failure is a serious complication in patients with cirrhosis. Pre-TIPS HVPG level may be used as a predictor of potential short-term postoperative adverse events.

Non-invasive diagnosis and follow-up of portal hypertension

Compensated advanced chronic liver disease (cACLD) describes the spectrum of advanced fibrosis/cirrhosis in asymptomatic patients at risk of developing clinically significant portal hypertension (CSPH, defined by a hepatic venous pressure gradient (HVPG) ≥10 mmHg). Patients with cACLD are at high risk of liver-related morbidity and mortality. In patients at risk of chronic liver disease, cACLD is strongly suggested by a liver stiffness (LSM) value >15 kPa or clinical/biological/radiological signs of portal hypertension, and ruled out by LSM <10 kPa, or Fibrotest® ≤0.58, or Fibrometer® ≤0.786. Patients with chronic liver disease (excluding vascular diseases) with a LSM <10 kPa are at low risk of developing portal hypertension complications. The presence of CSPH can be strongly suspected when LSM is ≥20 kPa. In a patient without clinical, endoscopic or radiological features of portal hypertension, measurement of the HVPG is recommended before major liver or intra-abdominal surgery, before extra-hepatic transplantation and in patients with unexplained ascites. Endoscopic screening for oesophageal varices can be avoided in patients with LSM <20 kPa and a platelet count >150 G/L (favourable Baveno VI criteria) at the time of diagnosis. There is no non-invasive method alternative for oeso-gastroduodenal endoscopy in patients with unfavourable Baveno criteria (liver stiffness ≥20 kPa or platelet count ≤50 G/l). Platelet count and liver stiffness measurements must be performed once a year in patients with cACLD with favourable Baveno VI criteria at the time of diagnosis. A screening oeso-gastroduodenal endoscopy is recommended if Baveno VI criteria become unfavourable.

Liver stiffness-based model predicts hepatic venous pressure gradient in patients with liver disease

BACKGROUND

The aim was to develop a model to predict clinically significant portal hypertension, hepatic venous pressure gradient (HVPG) ≥10 mmHg using pre-operative noninvasive makers.

METHODS

Patients who have been programmed for liver resection/transplantation were enrolled prospectively. Preoperative liver stiffness measurement (LSM), liver function test (LFT), and intraoperative HVPG were assessed. A probability score model to predict HVPG≥10 mmHg called HVPG₁₀ score was developed and validated.

RESULTS

A total of 161 patients [66% men, median age of 63 years] were recruited for the study. Median LSM, and HVPG were 9.5 kPa, and 5 mmHg respectively. HVPG₁₀ score was developed using independent predictors of HVPG≥10 mmHg in the training set were LSM, total bilirubin, alkaline phosphatase, and international normalized ratio. Area under receiver operating curve of HVPG₁₀ score in the training and validation sets were 0.91 and 0.93 respectively with a cutoff of 15. In the overall cohort, HVPG₁₀ score≥15 had 83% accuracy, 90% sensitivity, 81% specificity and 96% negative predictive value in predicting HVPG≥10 mmHg.

CONCLUSION

HVPG₁₀ score is an easy-to-use noninvasive continuous scale tool to rule out clinically significant portal hypertension in >95% patients with chronic liver disease.

A strategy for varices screening based on acoustic radiation force impulse combined with platelet (CHESS2001): An alternative of Baveno VI criteria

Few studies have reported on acoustic radiation force impulse (ARFI) for varices screening. Our study aimed to identify a strategy based on liver stiffness measurement (LSM) and spleen stiffness measurement (SSM) by ARFI combined with platelet count (PLT), named the ARP strategy, for ruling out high-risk varices (HRV) and avoiding unnecessary esophagogastroduodenoscopy (EGD) in patients with compensated cirrhosis. We retrospectively reviewed patients who underwent ARFI from a previous cohort (NCT04307264). Of them, patients between 2017 and 2019 composed the training cohort to develop the ARP strategy. The validation cohort consisted of others between 2015 and 2016 to validate and compare it with Baveno VI criteria about the performance for varices screening. Primary outcomes were the rates of spared EGDs and HRV missed. A total of 741 consecutive patients were included in the final analysis. Of them, 576 patients were included in the training cohort and 165 patients in the validation cohort. In the training cohort, ARP strategy was defined as LSM < 1.805 m/s or SSM < 2.445 m/s and PLT > 110 × 10⁹ /L. ARP strategy could spare 234 (40.6%) EGDs with a missed HRV rate of 3.4% (8 of 234). In the validation cohort, compared with Baveno VI criteria, the ARP strategy improved the proportion of avoided EGDs (49.7% vs. 34.5%; p < 0.001) and lowered the rate of misclassified HRV (1.2% vs. 3.5%; p < 0.001). Conclusion: The ARP strategy was an efficient and safe tool for varices screening in compensated cirrhosis, and it might be an auxiliary or even alternative to Baveno VI criteria.

Network Meta-Analysis: Noninvasive Imaging Modalities for Identifying Clinically Significant Portal Hypertension

BACKGROUND

Although measurement of the hepatic venous pressure gradient (HVPG) is the current reference standard for obtaining portal venous pressures, several noninvasive imaging-based modalities have been proposed as alternatives.

AIMS

We performed a systematic review and meta-analysis to compare the diagnostic accuracy of noninvasive imaging approaches for identifying clinically significant portal hypertension (CSPH).

METHODS

Two independent reviewers conducted a literature search of PubMed, SCOPUS, and the Cochrane Library from inception until January 5, 2021. The following imaging modalities were compared to HVPG: computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance elastography, ultrasound, transient elastography (TE), shear wave elastography (SWE), acoustic radiation force impulse (ARFI) imaging, contrast-enhanced ultrasound (CEUS), and subharmonic-aided pressure estimation (SHAPE). Sensitivity, specificity, diagnostic odds ratio (DOR), and area under the curve (AUC) for summary receiver operating characteristic were calculated using both frequentist random effects and Bayesian network meta-analytic approaches.

RESULTS

We analyzed 45 studies of 5678 patients. A broad overlapping confidence interval (CI) of DOR was observed among different imaging modalities: ARFI (30.5; 95% CI 12.7-73.3), CEUS and SHAPE (21.1; 95% CI 6.4-69.8), TE of liver stiffness (21.1; 95% CI 13.3-33.5), CT and MRI (13.7; 95% CI 7.40-25.4), SWE of liver stiffness (10.5; 95% CI 5.2-21.1), and ultrasound (9.5; 95% CI 4.9-18.4). The AUC of all imaging methods exceeded 0.8, indicating very good performance. At a cutoff of 80% specificity, TE, CEUS, and SHAPE exceeded 80% sensitivity.

CONCLUSION

Overall, noninvasive imaging modalities perform well for identifying CSPH. Clinicians should consider these noninvasive and cost-efficient tests when diagnosing CSPH.

A Prospective Study of Prevalence and Predictors of Cirrhotic Cardiomyopathy and Its Role in Development of Hepatorenal Syndrome

BACKGROUND AND AIMS

Cirrhotic cardiomyopathy (CCM) is a term used to collectively describe abnormal structural and functional changes in heart of patients with cirrhosis. The present study was undertaken to find the prevalence of CCM in patients with liver cirrhosis and its predictors. We also followed these patients to evaluate the role of CCM in the development of hepatorenal syndrome (HRS).

MATERIALS & METHODS

This was a prospective study carried out in department of Gastroenterology, Sir Ganga Ram hospital, New Delhi. A total of 104 patients with liver cirrhosis were included. Liver cirrhosis was diagnosed on basis of clinical, biochemical, and imaging features. CCM was defined based on echocardiography. Dobutamine stress echocardiography and hepatic venous pressure gradient (HVPG) were performed in patients who gave consent. HRS was defined as per standard criteria. Patients with CCM were followed for development of HRS.

RESULTS

Fifty (48%) patients were diagnosed with CCM. All patients had diastolic dysfunction, and none had systolic dysfunction. Median age of patients with CCM was significantly higher (59 [31-78 y] vs. 52 [24-70 y], P < 0.05). Severity of liver disease (Child Turcotte Pugh score and model for end-stage liver disease score) and portal pressures (HVPG) did not differ in patients with or without CCM. Patients with CCM did not have increased incidence of HRS at the end of 6-month follow-up study.

CONCLUSION

The presence of CCM was not related with the severity of liver dysfunction or portal pressures. Age was a significant determinant of CCM. Diastolic cardiac dysfunction does not influence the occurrence of HRS.

A Noninvasive Ultrasound Based Technique to Identify Treatment Responders in Patients with Portal Hypertension

RATIONALE AND OBJECTIVE

Subharmonic aided pressure estimation (SHAPE) is based on the inverse relationship between the subharmonic amplitude of ultrasound contrast microbubbles and ambient pressure. The aim of this study was to verify if SHAPE can accurately monitor disease progression in patients identified with portal hypertension.

MATERIALS & METHODS

A modified Logiq 9 scanner with a 4C curvi-linear probe (GE, Waukesha, WI) was used to acquire SHAPE data (transmitting and receiving at 2.5 and 1.25 MHz, respectively) using Sonazoid (GE Healthcare, Oslo, Norway; FDA IND 124,465). Twenty-one (median age 59 years; 12 Males) of the 178 patients enrolled in this institutional review board approved study (14F.113) were identified as having clinically significant portal hypertension based on their hepatic venous pressure gradient results ≥ 10 mmHg. Repeat SHAPE examinations were done every 6.2 months. Liver function tests and clinical indicators were used to establish treatment response.

RESULTS

Of the 21 portal hypertensive subjects, 11 had successful follow up scans with an average follow up time of 6.2 months. There was a significantly larger SHAPE signal reduction in the group who were classified as treatment responders (n = 10; -4.01±3.61 dB) compared to the single nonresponder (2.33 dB; p < 0.001). Results for responders matched the corresponding clinical outcomes of improved model for end stage liver disease (MELD) scores, improvement in underlying cause of portal hypertension, improved liver function tests and reduced ascites.

CONCLUSION

SHAPE can potentially monitor disease progression in portal hypertensive patients and hence, may help clinicians in patient management. A larger study would further validate this claim.

Artificial Intelligence in Imaging of Chronic Liver Diseases: Current Update and Future Perspectives

Here we review artificial intelligence (AI) models which aim to assess various aspects of chronic liver disease. Despite the clinical importance of hepatocellular carcinoma in the setting of chronic liver disease, we focus this review on AI models which are not lesion-specific and instead review models developed for liver parenchyma segmentation, evaluation of portal circulation, assessment of hepatic fibrosis, and identification of hepatic steatosis. Optimization of these models offers the opportunity to potentially reduce the need for invasive procedures such as catheterization to measure hepatic venous pressure gradient or biopsy to assess fibrosis and steatosis. We compare the performance of these AI models amongst themselves as well as to radiomics approaches and alternate modality assessments. We conclude that these models show promising performance and merit larger-scale evaluation. We review artificial intelligence models that aim to assess various aspects of chronic liver disease aside from hepatocellular carcinoma. We focus this review on models for liver parenchyma segmentation, evaluation of portal circulation, assessment of hepatic fibrosis, and identification of hepatic steatosis. We conclude that these models show promising performance and merit a larger scale evaluation.

Noninvasive Assessment of Hepatitis C Virus Infected Patients Using Vibration-Controlled Transient Elastography

Chronic infection with hepatitis C virus (HCV) is one of the leading causes of cirrhosis and hepatocellular carcinoma (HCC). Surveillance of these patients is an essential strategy in the prevention chain, including in the pre/post-antiviral treatment states. Ultrasound elastography techniques are emerging as key methods in the assessment of liver diseases, with a number of advantages such as their rapid, noninvasive, and cost-effective characters. The present paper critically reviews the performance of vibration-controlled transient elastography (VCTE) in the assessment of HCV patients. VCTE measures liver stiffness (LS) and the ultrasonic attenuation through the embedded controlled attenuation parameter (CAP), providing the clinician with a tool for assessing fibrosis, cirrhosis, and steatosis in a noninvasive manner. Moreover, standardized LS values enable proper staging of the underlying fibrosis, leading to an accurate identification of a subset of HCV patients that present a high risk for complications. In addition, VCTE is a valuable technique in evaluating liver fibrosis prior to HCV therapy. However, its applicability in monitoring fibrosis regression after HCV eradication is currently limited and further studies should focus on extending the boundaries of VCTE in this context. From a different perspective, VCTE may be effective in identifying clinically significant portal hypertension (CSPH). An emerging prospect of clinical significance that warrants further study is the identification of esophageal varices. Our opinion is that the advantages of VCTE currently outweigh those of other surveillance methods.

Noninvasive Detection of Clinically Significant Portal Hypertension in Compensated Advanced Chronic Liver Disease

Patients with compensated advanced chronic liver disease have different prognoses depending on the presence of portal hypertension. Current non-invasive diagnostic methods allow identification of clinically significant portal hypertension. Portosystemic collaterals on imaging or liver stiffness of more than 20 to 25 kPa by using transient elastography identifies patients with clinically significant portal hypertension. Patients with liver stiffness of less than 20 kPa and platelet count of greater than 150 g/L can avoid endoscopy. This rule could be expanded using spleen stiffness. Methods to risk stratify for portal hypertension in compensated advanced chronic liver disease and successfully treated chronic hepatitis C and B are subject of research.

Liver stiffness assessment as an alternative to hepatic venous pressure gradient for predicting rebleed after acute variceal bleed: A proof-of-concept study

Background and Aim

Hepatic venous pressure gradient (HVPG), although an important determinant in predicting rebleeding after an episode of acute variceal bleed (AVB), is seldom utilized in clinical practice. We aimed to study the role of liver stiffness measurement (LSM) after variceal bleeding as a potential noninvasive predictor of rebleed.

Methods

This was a post hoc analysis of clinical trial of patients undergoing HVPG (postbleed HVPG) and LSM (postbleed LSM) assessment within 3–5 days of index AVB. HVPG response was assessed after 4 weeks of pharmacotherapy. Comparative assessment of long‐term rebleeding rates stratified using postbleed LSM, postbleed HVPG, and HVPG response was performed. Decision curve analysis (DCA) was conducted to identify the most appropriate tool for routine use.

Results

Long‐term clinical and HVPG response data were available for 48 patients post‐AVB, of whom 45 patients had valid postbleed LSM. Rebleeding occurred in 13 (28%) patients over a median follow‐up of 4 years with no early rebleeds. Postbleed LSM >30 kPa and baseline HVPG >15 mm Hg were optimal cutoffs for identifying patients at high risk of rebleeding. Time‐dependent receiver operating characteristic curves and competing risk analysis accounting for death showed similar discriminative values for all three stratification tools. At usual risk thresholds, HVPG response had maximum benefit on DCA followed by postbleed LSM. On DCA, 50–60 additional HVPGs were required to detect one additional patient at high risk of rebleed.

Conclusion

Liver stiffness measurement during AVB can potentially be used as an alternative to portal pressure indices in decompensated cirrhosis to identify those at high risk of late‐onset rebleed.

Noninvasive imaging assessment of portal hypertension

Portal hypertension (PH) is a spectrum of complications of chronic liver disease (CLD) and cirrhosis, with manifestations including ascites, gastroesophageal varices, splenomegaly, hypersplenism, hepatic hydrothorax, hepatorenal syndrome, hepatopulmonary syndrome and portopulmonary hypertension. PH can vary in severity and is diagnosed via invasive hepatic venous pressure gradient measurement (HVPG), which is considered the reference standard. Accurate diagnosis of PH and assessment of severity are highly relevant as patients with clinically significant portal hypertension (CSPH) are at higher risk for developing acute variceal bleeding and mortality. In this review, we discuss current and upcoming noninvasive imaging methods for diagnosis and assessment of severity 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.

Combined effect of hepatic venous pressure gradient and liver stiffness on long-term mortality in patients with cirrhosis

BACKGROUND/AIMS

Both hepatic venous pressure gradient (HVPG) and liver stiffness (LS) are useful tools for predicting mortality in patients with cirrhosis. We investigated the combined effect of HVPG and LS on long-term mortality in patients with cirrhosis.

METHODS

We retrospectively collected data from 103 patients with cirrhosis, whose HVPG and LS were measured between November 2009 and September 2013. The patients were divided into four groups according to the results of the HVPG and LS measurements. Long-term mortality and the risk factors for mortality were analyzed.

RESULTS

Of the 103 patients, 35 were in group 1 (low HVPG and low LS), 16 in group 2 (high HVPG and low LS), 24 in group 3 (low HVPG and high LS), and 28 in group 4 (high HVPG and high LS). Over a median follow-up of 47.3 months, 18 patients died. The mortality rate of patients in group 4 was significantly higher than in the other three groups (vs. group 1, p = 0.005; vs. group 2, p = 0.049; vs. group 3, p = 0.004), but there were no significant differences in survival between groups 1, 2, and 3. In multivariable analyses, both HVPG and LS were identified as independent risk factors for mortality (hazard ratio [HR], 1.127, p = 0.018; and HR, 1.062, p = 0.009, respectively).

CONCLUSION

In patients with cirrhosis, those with concurrent elevation of HVPG and LS had the highest long-term mortality rates. However, when either HVPG or LS alone was elevated, mortality did not increase significantly.

Diagnostic accuracy of non-invasive methods detecting clinically significant portal hypertension in liver cirrhosis: a systematic review and meta-analysis

INTRODUCTION

We attempted to investigate non-invasive techniques and their diagnostic performances for evaluating clinically significant portal hypertension.

EVIDENCE ACQUISITION

The systematic search was performed on PubMed, Embase, Scopus, and Web of Science TM core index databases before 13 December 2018 restricted to English language and human studies.

EVIDENCE SYNTHESIS

Thirty-two studies were included, with total populations of 3,987. The overall pooled analysis was performed by bivariate random effect model, which revealed significantly higher sensitivity and specificity of 77.1% (95% confidence interval, 76.8-78.5%) and 80.1% (95% confidence interval, 78.2-81.9%), respectively; positive likelihood ratio (3.67), negative likelihood ratio (0.26); and diagnostic odd ratio (16.24). Additionally, the area under curve exhibited significant diagnostic accuracy of 0.871. However, notable heterogeneity existed in between studies (I2=87.1%), therefore, further subgroup analysis was performed. It demonstrated ultrasonography, elastography, biomarker, and computed tomography scan had a significant overall summary sensitivity (specificity) of 89.6% (78.9%), 81.7% (83.2%), 72.2% (76.8%), and 77.2% (81.2%), respectively. Moreover, the areas under curve values were significantly higher in elastography (0.906), followed by computed tomography scan (0.847), biomarker (0.825), and ultrasonography (0.803).

CONCLUSIONS

In future, non-invasive techniques could be the future choice of investigations for screening and diagnosis of clinically significant portal hypertension in cirrhosis. However, standardization of diagnostic indices and their cut-off values in each non-invasive method needs to be addressed.

Portal pressure monitoring-state-of-the-art and future perspective

Portal hypertension is a serious symptom of chronic liver diseases, which can lead to many critical complications, such as the formation of varices related to upper digestive bleeding, ascites, infection, hepatic encephalopathy, renal failure, and even death. As a result, portal pressure monitoring has important prognostic and clinical implications. The hepatic venous pressure gradient measurement, a gold-standard method applied to monitor portal pressure, is invasive and only available in experienced centers. Over the past decade, noninvasive methods aimed at monitoring the portal pressure have been increasingly investigated, including serum markers, radiological features, ultrasound elastography, doppler and contrast-enhanced ultrasonography. In this study, we focused on both invasive and noninvasive methods for portal pressure monitoring and explored their roles in clinical setting. The advantages and limitations of various techniques for future research are also discussed.

Role of Spleen Stiffness Measurement by 2D-Shear Wave Elastography in Ruling Out the Presence of High-Risk Varices in Cirrhotic Patients

BACKGROUND AND AIM

To evaluate if spleen stiffness measurement (SSM) can rule out the presence of high-risk varices in patients with cirrhosis, avoiding an upper gastrointestinal endoscopy (UGE).

METHODS

We enrolled 71 cirrhotic patients irrespective of liver disease's etiology. 2D shear wave elastography (SWE) of spleen and UGE was performed. High-risk varices (HRV) were defined as esophageal varices ≥ 5 mm and/or red spots and any gastric varices.

RESULTS

Esophageal varices were documented in 37 (52.1%) and HRV in 25 (35.2%) patients. SSM was not technically feasible in 7/71 patients (9.8%). From the remaining 64 patients, when those with cholestatic liver disease were excluded (n = 17), SSM < 35.8 kPa was found to exclude well the existence of HRV offering an AUROC of 0.854 (p < 0.001), sensitivity 88.9%, negative predictive value (NPV) 91.3%, specificity 72.4%, and positive predictive value (PPV) 66.7%. Only 2/47 patients (4.3%) were misclassified, and 23 (48.9%) could avoid endoscopy. In the total cohort of 64 patients, SSM < 33.7 kPa was found to exclude well the presence of HRV offering AUROC 0.792 (p < 0.001), sensitivity 91.7%, specificity 60%, NPV 92.3%, and PPV 57.9%. The misclassification rate was 3.1% (2/64), while 26/64 (40.6%) could avoid endoscopy.

CONCLUSIONS

2D-SWE of spleen is a reliable method for ruling out the presence of HRV in cirrhotic patients. If larger studies confirm our results, a large number of endoscopies could be avoided.

Evaluation of portal hypertension in the cirrhotic patient: hepatic vein pressure gradient and beyond

Portal hypertension (PH) is a major complication of liver cirrhosis, as it predisposes to the development of serious clinical manifestations such as ascites, hepatic encephalopathy and variceal bleeding. Till now, the measurement of hepatic vein pressure gradient (HVPG) is the gold standard method to ascertain the presence and significance of PH, as many studies have shown its correlation with the appearance of varices and the possibility of variceal bleeding. However, the invasiveness of this procedure makes it difficult to be used in daily clinical practice. Several noninvasive methods with adequate capability of evaluating liver fibrosis, including elastographic techniques, are currently used as alternatives to HVPG in order to assess the presence and the severity of PH. The aim of this paper is to express an overview of the literature about the actual role of HVPG and all available noninvasive tests on the prediction of development of PH complications, to highlight their advantages and their potential limitations, and to provide the latest trends on clinical practice.

Is Kidney Stiffness Measured Using Elastography Influenced Mainly by Vascular Factors in Patients with Diabetic Kidney Disease?

Studies published so far using ultrasound-based elastography in the kidneys, lack to prove a clear relationship between kidney shear wave speed (KSWS) and renal disease progression. Taking into account that the kidney is a highly vascularized organ, the present study aims to find a relationship between KSWS and vascular factors (blood pressure [BP], arterial stiffness). Our study included 38 diabetic kidney disease patients (mean age 56.52 ± 16.12 years, 19 female, 19 male). KSWS, an indicator of renal stiffness, was measured using point Shear Wave Elastography (pSWE; Siemens Acuson S2000). In every patient, we recorded BP, and we measured aortic augmentation index (AAI) and brachial pulse wave velocity (PWV), using oscillometry. We found statistically significant indirect correlations of KSWS with indicators of arterial stiffness, such as PWV ( r = -.41, p = .036), and AAI ( r = -.37, p = .031). We found also an indirect correlation of KSWS with diastolic BP ( r = -.65, p = .02) and systolic BP ( r = -.54, p = .008). We found no correlation of KSWS with estimated glomerular filtration rate (eGFR), urinary albumin/creatinine ratio, stage of diabetic retinopathy, or glycated hemoglobin. Our study shows that high BP and the progression of arteriosclerosis (high PWV and AAI), leads to a decrease of renal stiffness. Thus, it seems that KSWS is influenced by renal blood flow, rather than other factors, such as albuminuria or chronic kidney disease stage.

Non-invasive aspartate aminotransferase to platelet ratio index correlates well with invasive hepatic venous pressure gradient in cirrhosis

BACKGROUND

Hepatic venous pressure gradient (HVPG) is the best recommended tool to measure portal pressure, but is invasive. HVPG helps in prognosticating cirrhosis and predict its complications. Aminotransferase to platelet ratio index (APRI) is a simple non-invasive marker of hepatic fibrosis. We aimed to correlate APRI with HVPG and to determine the usefulness of APRI in predicting complication of cirrhosis.

METHODS

APRI and HVPG were measured in consecutive patients of cirrhosis aged 18 to 70 years. Spearman's rho was used to estimate their correlation; a cut-off value of APRI to predict severe portal hypertension (HVPG > 12 mmHg) was determined.

RESULTS

This study, conducted between August 2011 and December 2014, included 277 patients, median age 51 (range: 16-90) years, 84% males. Etiology of cirrhosis was alcohol in 135 (49%), cryptogenic/nonalcoholic steatohepatitis (NASH) in 104 (38%), viral in 34 (12%), and others in 4 (1%). Median Child-Turcott-Pugh (CTP) and model for end-stage liver disease (MELD) scores were 7 (5-11) and 11 (6-33), respectively. Median HVPG was 17.0 (1.5-33) mmHg and median APRI was 1.09 (0.21-12.22). There was positive correlation between APRI and HVPG (Spearman's rho 0.450, p < 0.001). The area under the receiver operating characteristic (ROC) curve of APRI for predicting severe portal hypertension was 0.763 (p < 0.01). Youden's index defined the cut-off of APRI for predicting HVPG > 12 mmHg was 0.876 with a sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of 71%, 78%, 94%, 38%, and 73%, respectively. APRI also correlated well with CTP, variceal size, bleeding status, ascites but not with MELD.

CONCLUSIONS

APRI score of 0.876 has an acceptable accuracy to predict severe portal hypertension (HVPG > 12 mmHg). High APRI also correlated with severity of cirrhosis and its complications. Thus, APRI may be used as a simple, bedside, non-invasive, and inexpensive tool for evaluating portal hypertension and complications of cirrhosis.

Performance of spleen stiffness measurement in prediction of clinical significant portal hypertension: A meta-analysis

AIM

Our purpose was to evaluate the correlation between spleen stiffness (SS) measured by ultrasound-based elastography and hepatic venous pressure gradient (HVPG) and assess the accuracy of SS in detecting clinical significant portal hypertension (CSPH) and severe portal hypertension.

METHOD

Nine studies were included from thorough literature research and selection processes. A random model was used to analyze the correlation between HVPG and SS. We adopted the bivariate mixed effects model to assess the diagnostic performance.

RESULTS

Regarding to correlation between SS and HVPG, the summary correlation coefficient was 0.72 (95% confidence interval [CI], 0.63-0.80). In detection of CSPH, the sensitivity, specificity, AUC and DOR were: 0.88 (0.70-0.96), 0.84 (0.72-0.92), 0.92 (0.89-0.94) and 38 (17-84) for CSPH, respectively; and 0.92 (0.82-0.96), 0.79 (0.72-0.85), 0.87 (0.84-0.90) and 41 (17-100) for severe portal hypertension, respectively.

CONCLUSION

Correlation between SS and HVPG was good. Although SS showed good sensitivity and specificity, the different cut-off values and techniques among studies might limit the impact of our results on clinical practice. Therefore, more high-quality prospective studies are required to evaluate the role of SS in predicting portal hypertension.

Comparison of three cut-offs to diagnose clinically significant portal hypertension by liver stiffness in chronic viral liver diseases: a meta-analysis

BACKGROUND

Transient elastography-based liver stiffness value (TE-LSV) has been investigated for assessing clinically significant portal hypertension (CSPH). The aetiology of CSPH is an important factor determining TE-LSV. There is insufficient evidence for selecting cut-off values.

AIMS

This study performed a meta-analysis to compare the three most widely used cut-off values (around 13.6 kPa, 18 kPa and 22kPa) of TE-LSV for the diagnosis of CSPH in patients with chronic viral liver disease.

METHODS

The PubMed, Ovid, Web of Science and Cochrane Library databases were searched. Diagnostic data for cut-off values around 13.6 kPa, 18 kPa and 22 kPa in each included study were extracted. The bivariate model was performed to estimate pooled sensitivity, specificity, positive likelihood ratio (LR+) and negative likelihood ratio (LR-).

RESULTS

Eleven studies assessing 910 patients were included in this meta-analysis. Pooled sensitivities of cut-off values around 13.6 kPa, 18 kPa and 22 kPa were 0.96 (95% CI 0.93-0.97), 0.85 (0.81-0.89) and 0.74 (0.66-0.80), respectively; pooled specificities were 0.60 (0.47-0.75), 0.80 (0.71-0.87) and 0.94 (0.86-0.97), respectively. Pooled LR+ values were 2.4 (1.6-3.7), 4.4 (2.9-6.8) and 11.5 (5.5-23.5) for cut-off values around 13.6 kPa, 18 kPa and 22 kPa, respectively, for pooled LR- values of 0.07 (0.04-0.13), 0.17 (0.12-0.25) and 0.28 (0.22-0.36), respectively.

CONCLUSION

Cut-off values around 13.6 kPa (high sensitivity) and 22 kPa (high specificity) could be used as screening and confirmation tools, respectively, in the diagnosis of CSPH. Overall, the cut-off value around 22 kPa showed the best performance.

KEY POINTS

Transient elastography-based liver stiffness could be used to diagnose portal hypertension. Comparison of certain cut-off values would provide more information for clinical decision-making. Cut-off around 13.6 kPa was able to exclude clinically significant portal hypertension (CSPH) effectively. Cut-off around 22 kPa was able to confirm CSPH effectively.

Origins of Portal Hypertension in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) advanced to cirrhosis is often complicated by clinically significant portal hypertension, which is primarily caused by increased intrahepatic vascular resistance. Liver fibrosis has been identified as a critical determinant of this process. However, there is evidence that portal venous pressure may begin to rise in the earliest stages of NAFLD when fibrosis is far less advanced or absent. The biological and clinical significance of these early changes in sinusoidal homeostasis remains unclear. Experimental and human observations indicate that sinusoidal space restriction due to hepatocellular lipid accumulation and ballooning may impair sinusoidal flow and generate shear stress, increasingly disrupting sinusoidal microcirculation. Sinusoidal endothelial cells, hepatic stellate cells, and Kupffer cells are key partners of hepatocytes affected by NAFLD in promoting endothelial dysfunction through enhanced contractility, capillarization, adhesion and entrapment of blood cells, extracellular matrix deposition, and neovascularization. These biomechanical and rheological changes are aggravated by a dysfunctional gut-liver axis and splanchnic vasoregulation, culminating in fibrosis and clinically significant portal hypertension. We may speculate that increased portal venous pressure is an essential element of the pathogenesis across the entire spectrum of NAFLD. Improved methods of noninvasive portal venous pressure monitoring will hopefully give new insights into the pathobiology of NAFLD and help efforts to identify patients at increased risk for adverse outcomes. In addition, novel drug candidates targeting reversible components of aberrant sinusoidal circulation may prevent progression in NAFLD.

INASL Position Statements on Prevention, Diagnosis and Management of Hepatitis B Virus Infection in India: The Andaman Statements

Hepatitis B Virus (HBV) infection is one of the major causes of morbidity, mortality and healthcare expenditure in India. There are no Indian consensus guidelines on prevention, diagnosis and management of HBV infection. The Indian National Association for Study of the Liver (INASL) set up a taskforce on HBV in 2016, with a mandate to develop consensus guidelines for diagnosis and management of HBV infection, relevant to disease patterns and clinical practices in India. The taskforce first identified contentious issues on various aspects of HBV management, which were allotted to individual members of the taskforce who reviewed them in detail. A 2-day round table discussion was held on 11th and 12th February 2017 at Port Blair, Andaman & Nicobar Islands, to discuss, debate, and finalize the consensus statements. The members of the taskforce reviewed and discussed the existing literature threadbare at this meeting and formulated the 'INASL position statements' on each of the issues. The evidence and recommendations in these guidelines have been graded according to the Grading of Recommendations Assessment Development and Evaluation (GRADE) system with minor modifications. The strength of recommendations (strong: 1, weak: 2) thus reflects the quality (grade) of underlying evidence (A, B, C, D). We present here the INASL position statements on prevention, diagnosis and management of HBV in India.

Assessing Hepatic Fibrosis Using 2-D Shear Wave Elastography in Patients with Liver Tumors: A Prospective Single-Center Study

The purpose of this study was to investigate the diagnostic performance of 2-D shear wave elastography (2-D-SWE) in evaluations of liver stiffness in patients with liver tumors before resection. A total of 121 consecutive patients with hepatocellular carcinoma (HCC) (n = 93), intra-hepatic cholangiocarcinoma (n = 6), mixed hepatocellular carcinoma and intra-hepatic cholangiocarcinoma (n = 6), liver metastases (n = 10) and benign tumors (n = 6) were prospectively enrolled in this study from June 2015 to March 2016. Three valid 2-D-SWE measurements for each patient and median liver stiffness values were calculated. Fibrosis staging was evaluated according to the METAVIR scoring system. A receiver operating characteristic curve analysis was used to assess diagnostic performance. In this study, we found that median liver stiffness values were significantly higher in patients with primary liver tumors than in those with liver metastases and benign tumors (11.80 kPa vs. 5.85 kPa, p < 0.001). In addition, liver stiffness, assessed using 2-D-SWE, was highly correlated with pathologically confirmed liver fibrosis stage. Liver fibrosis stage and liver stiffness values were analyzed using Spearman's correlation (0.708, p < 0.001). The median liver stiffness values were as follows: F1, 6.7 kPa; F2, 6.33 kPa; F3, 9.2 kPa; F4, 13.7 kPa. The area under the receiver operating characteristic curves of the liver stiffness values that predicted significant fibrosis (≥F2), severe fibrosis (≥F3) and cirrhosis (=F4) were 83.5%, 91.6% and 88.1%, respectively. According to the Youden index, the optimal cutoff values for predicting significant fibrosis (≥F2), severe fibrosis (≥F3) and cirrhosis (=F4) were 7.05 kPa (sensitivity = 74.6%, specificity = 100.0%), 9.45 kPa (sensitivity = 78.8%, specificity = 100.0%) and 11.1 kPa (sensitivity = 83.1%, specificity = 89.3%), respectively. We conclude that 2-D-SWE is a useful, accurate and non-invasive method for evaluating hepatic fibrosis in patients with liver tumors adapted to hepatectomy (ClinicalTrials.gov ID: NCT02958592).