Accuracy of non-invasive methods/models for predicting esophageal varices in patients with compensated advanced chronic liver disease secondary to nonalcoholic fatty liver disease

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.

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

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

Validation of Baveno VI and Expanded-Baveno VI Criteria for predicting gastroesophageal varices in patients with alcoholic and non-alcoholic fatty liver disease

Background and aims: Baveno VI and Expanded-Baveno VI Criteria were validated to rule out high-risk esophageal varices (HRV) and to prevent unneeded endoscopies in compensated advanced chronic liver disease (cACLD) mainly related to viral hepatitis. We aim to assess these criteria to rule out low- and high- risk varices in patients with cACLD secondary to alcoholic liver disease (ALD) and non- alcoholic fatty liver disease (NAFLD). Methods: Data were collected retrospectively from 2016 to 2020. Inclusion criteria were: NAFLD and /or ALD related cACLD, a liver stiffness measurement (LSM) ≥ 10 kPa and an esophagogastroduodenoscopy (EGD) within 12 months. Exclusion criteria were: use of non cardioselective β-blockers, hepatic decompensation, previous variceal bleeding, portal thrombosis, liver cancer, or liver transplant. Results: One hundred and ninety-four patients were included in this study. Eighty-one patients (42%) met Baveno VI criteria and 103 (53%) met Expanded-Baveno VI criteria. Baveno VI criteria yielded a high negative predictive value (NPV ≥ 95%) for detecting HRV and varices of any size. Expanded-Baveno VI criteria yielded a high NPV ≥ 95% only for detecting HRV: the miss rate for varices of any size was 8%. Expanded-Baveno VI criteria could avoid more endoscopies than the original Baveno VI criteria to rule out HRV (53% versus 42%). Conclusion: In this study, both criteria showed high NPV to rule out HRV but only original Baveno VI criteria yielded a satisfactory high NPV to rule out varices of any size. Expanded-Baveno VI criteria could avoid more endoscopies to exclude HRV.

The Value of Liver and Spleen Stiffness for Evaluation of Portal Hypertension in Compensated Cirrhosis

Patients with compensated advanced chronic liver disease who develop clinically significant portal hypertension (CSPH) are at high risk for hepatic decompensation and mortality if left untreated. Liver biopsy and hepatic venous pressure gradient (HVPG) measurements are the current gold standard procedures for determining fibrosis severity and diagnosing CSPH, respectively; however, both are invasive, limiting their use in clinical practice and larger trials of novel agents. As such, there is an unmet clinical need for reliable, validated, noninvasive measures to detect CSPH and to further assess portal hypertension (PH) severity. Alterations in the biomechanical properties of the liver or spleen in patients with cirrhosis can be quantified by tissue elastography, which examines the elastic behavior of tissue after a force has been applied. A variety of methods are available, including magnetic resonance elastography, shear-wave elastography, and the most thoroughly investigated measure, vibration-controlled transient elastography. Liver stiffness (LS) and spleen stiffness (SS) measurements offer valuable alternatives to detect and monitor CSPH. Both LS and SS correlate well with HVPG, with thresholds of LS >20-25 kPa and SS >40-45 kPa indicating a high likelihood of CSPH. Because SS is a direct and dynamic surrogate of portal pressure, it has the potential to monitor PH severity and assess PH improvement as a surrogate marker for clinical outcomes. Importantly, SS seems to be superior to LS for monitoring treatment response in clinical trials focusing on reducing PH.

Noninvasive assessment oesophageal varices: impact of the Baveno VI criteria

PURPOSE OF REVIEW

In 2015, as a consequence of the high development in noninvasive tests, Baveno VI consensus recommended for the first time the use of a prediction rule (liver stiffness <20kPa and platelet count > 150000) to identify patients at low risk of having varices and that could circumvent endoscopy. These became known as the Baveno VI criteria. We review here the data validating Baveno VI criteria and we discuss the attempts of expanding these criteria.

RECENT FINDINGS

We report 28 studies assessing the performance of Baveno VI criteria showing a pooled 99% negative predictive value for ruling out high-risk varices. Performance is not affected by the cause of cirrhosis. Different attempts at expanding these criteria show suboptimal performance. Nonelastography-based criteria require further validation.

SUMMARY

Baveno VI criteria can be safely used to avoid endoscopy in a substantial proportion of patients with compensated cirrhosis. The progressive change in approach to the management of compensated cirrhosis, progressively focusing on treating portal hypertension with beta-blockers independently of the presence of varices, might render these criteria less relevant.