Portal vein flow velocity as a possible fast noninvasive screening tool for esophageal varices in cirrhotic patients

Underfunding of German university-based high-performance medicine exemplified by the treatment of varices in cirrhosis

Facing increasing economization in the health care sector, clinicians have to adapt not only to the ever-growing economic challenges, but also to a patient-oriented health care. Treatment costs are the most important variable for optimizing success when facing scarce human resources, increasing material- and infrastructure costs in general, as well as low revenue flexibility due to flat rates per case in Germany, the so-called Diagnosis-Related Groups (DRG). University hospitals treat many patients with particularly serious illnesses. Therefore, their share of complex and expensive treatments, such as liver cirrhosis, is significantly higher. The resulting costs are not adequately reflected in the DRG flat rate per case, which is based on an average calculation across all hospitals, which increases this economic pressure. Thus, the aim of this manuscript is to review cost and revenue structures of the management of varices in patients with cirrhosis at a university center with a focus on hepatology. For this monocentric study, the data of 851 patients, treated at the Gastroenterology Department of a University Hospital between 2016 and 2020, were evaluated retrospectively and anonymously. Medical services (e.g., endoscopy, radiology, laboratory diagnostics) were analyzed within the framework of activity-based-costing. As part of the cost unit accounting, the individual steps of the treatment pathways of the 851 patients were monetarily evaluated with corresponding applicable service catalogs and compared with the revenue shares of the cost center and cost element matrix of the German (G-) DRG system. This study examines whether university-based high-performance medicine is efficient and cost-covering within the framework of the G-DRG system. We demonstrate a dramatic underfunding of the management of varicose veins in cirrhosis in our university center. It is therefore generally questionable whether and to what extent an adequate care for this patient collective is reflected in the G-DRG system.

Measurement of portal vein indices and splenic index by ultrasound and their association with gastroesophageal varices in cirrhosis of liver

Background and Objectives

Esophageal and gastric fundic varices are common in liver cirrhosis patients. Ultrasound with the Doppler study assesses liver cirrhosis severity, measuring portal vein and splenic indices' association with gastroesophageal varices.

Methodology

This study was conducted on 64 subjects with sonographic features of chronic liver disease who were referred for routine follow-up scans. Portal vein diameter, average velocity, splenic index, congestion index (CI), and portal vein area and velocity were measured.

Result

Subjects with gastroesophageal varices had significantly larger portal vein diameters (14.7±1.64 mm) compared to those without varices (12.05±1.26 mm) (P<0.05). Conversely, subjects without varices exhibited a higher portal vein velocity of (17.9±0.6 cm/s) than with varices (13.91±2.01 cm/s) (P=0.0005). The splenic index was higher in subjects with varices (1120±494 cm3) than those without varices (419 cm3) (P<0.05). The CI was also higher in subjects with varices. Portal vein velocity showed the highest sensitivity (94%) with a cutoff of 19 cm/s, while the CI had the highest diagnostic accuracy (93.75%) with a cutoff of 0.10 cm xsec. The splenic index demonstrated a sensitivity of 92.85% and diagnostic accuracy of 92.18% with a cutoff of 480 cm3. The splenic index followed by the CI is found to be a better predictor of esophageal varices (area under the curve of 96.8 and 96%, respectively).

Conclusion

Ultrasonographic assessment of the portal vein and spleen is a reliable, noninvasive method for predicting gastroesophageal varices in liver cirrhosis. The splenic index and CI have high diagnostic accuracy.

A systematic review and meta-analysis of portal vein morphometry in pediatric and adult populations: Drawing the line between normal and abnormal findings

PURPOSE

The morphometry of the hepatic portal vein is of clinical importance, particularly in pre-operative assessments, surgical management, and diagnoses of liver conditions. This systematic review and meta-analysis aimed to characterize the morphometry of the normal portal vein in both pediatric and adult patients.

METHODS

The study, conducted using the PRISMA guidelines and registered with PROSPERO, utilized the MEDLINE, EMBASE, SCOPUS and Web of Science databases up to May 2020, and updated to May 2023. All studies reporting extractable data on diameter, length, and cross-sectional area (CSA) of the main, left, and right portal veins (PV, LPV, RPV, respectively) were included. The AQUA Tool was used to assess the quality of the included studies. Data analysis included subgroup analyses based on geographical location, sex, age, and imaging modality.

RESULTS

A total of 122 studies with 11,637 subjects were eligible for inclusion. Overall, the pooled mean diameter of the PV (PVD) was 10.09 mm (95% CI: 9.56-10.62). Significant differences in diameter were found between pediatric (6.60 mm; 95% CI: 5.38-7.82) and adult (10.72 mm; 95% CI: 10.25-11.19) subjects. Additionally, there was a significantly larger PVD measurement from computed tomography (CT) than other imaging modalities: CT, 13.28 mm (95% CI: 11.71-14.84); magnetic resonance imaging (MRI), 10.50 mm (95% CI: 9.35-11.66) and ultrasound (US), 9.81 mm (95% CI: 9.47-10.16). The mean diameters of the LPV and RPV were 8.27 mm (95% CI: 6.78-9.77) and 8.33 mm (95% CI: 6.70-9.95), respectively. Mean PV length in adults is 48.63 mm (95% CI: 35.63-61.64). Mean CSA of the PV was 1.09 cm2.

CONCLUSIONS

The study obtained aim to improve the understanding of portal vein anatomy, especially with relevance to surgical interventions of the liver in both pediatric and adult patients. Measurements from ultrasound imaging closely approximates the generated pooled PVD mean for pediatric and adult patients. CT imaging, however, significantly exceeded the established 13 mm threshold for adults. For pediatric patients, a threshold of 8 mm is proposed as a diagnostic upper limit for a normal PVD. Although not significant, the PVD decreased from the portal confluence towards its bifurcation.

Diagnostic Accuracy of Portal Vein Flow Velocity for Esophageal Varices in Cirrhotic Patients

Background Variceal bleeding is a life-threatening complication of cirrhosis. Traditionally, endoscopy has been utilized as a preferred modality for the detection and grading of esophageal varices. However, endoscopy is an invasive procedure and may not be readily available in resource-limited settings. To overcome this limitation, various non-invasive tests, including Doppler ultrasonography (DUS) with portal vein (PV) velocity measurement, have been investigated to predict the presence of esophageal varices (EV). This study aimed to evaluate the potential utility of portal vein flow velocity (PVFV) as a non-invasive alternative to endoscopic screening for predicting the presence of esophageal varices among cirrhotic patients. Methodology This validation cross-sectional study was carried out at the Department of Gastroenterology and Hepatology, Pakistan Kidney and Liver Institute & Research Centre (PKLI&RC), Lahore, Pakistan from June 8, 2022, to March 8, 2023. Cirrhotic patients were enrolled based on clinical, laboratory, and radiological assessments. Doppler ultrasonography was performed to measure portal vein flow velocity along other relevant indices. Subsequently, all patients underwent endoscopic evaluation to screen and grade the esophageal varices. Univariate and multivariate logistic regression analyses were performed to identify significant clinical predictors of EV based on the results of the independent sample t-tests or Mann-Whitney U tests. Receiver operating characteristic (ROC) curves were employed to determine the optimal cut-off value for portal vein flow velocity (PVFV). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were calculated based on the identified cut-off value. A p-value ≤ 0.05 was considered statistically significant. Results A cohort of 137 cirrhotic patients was enrolled. The study population consisted of 92 males (67.2%) and 45 females (32.8%). Endoscopic screening confirmed the presence of esophageal varices in 81 patients (59.91%). A multivariate analysis revealed that aspartate aminotransferase to platelet ratio index (APRI) (p=0.008) and portal vein flow velocity (p=0.001) were significant factors associated with esophageal varices and were used for receiver operating characteristic (ROC) analysis. The area under the curve (AUC) for PVFV was 0.981, and for APRI, it was 0.711. At a cut-off value of 18 cm/sec for PVFV, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy for esophageal varices were found to be 93.83%, 92.86%, 95%, 91.23%, and 93.43%, respectively. Conclusion Measurement of portal vein flow velocity using Doppler ultrasonography (DUS) is a reliable screening method for predicting the presence of esophageal varices (EV) in patients with liver cirrhosis. DUS offers several advantages, including its non-invasive nature, cost-effectiveness, and widespread availability, making it a recommended approach due to its high diagnostic accuracy.

Comparison of portal vein hemodynamics with ultrasound-based elastography for the prediction of liver fibrosis in patients with chronic liver disease

Chronic liver disease includes nonalcoholic fatty liver disease, progresses from steatosis and hepatitis to fibrosis and cirrhosis, with hemodynamic changes in portal blood flow. This study aimed to compare portal vein hemodynamics with liver stiffness (LS) and steatosis and included 28 subjects with chronic liver disease, in whom LS and steatosis were evaluated in the same image employing two elastography techniques: transient elastography (TE) with controlled attenuation parameter (CAP) using a FibroScan and two-dimensional shear-wave elastography (2D-SWE) with attenuation imaging (ATI). Additionally, peak maximum velocity (V_max) of the right portal vein and spleen stiffness with 2D-SWE were evaluated. A strong positive correlation was present between LS values obtained with TE and 2D-SWE and between the attenuation coefficients of steatosis obtained with CAP and ATI. Additionally, a negative correlation was present between LS values and the V_max of the right portal vein (r = 0.415, p = 0.031). The optimal V_max cutoff value for discriminating liver fibrosis with an LS value of > 5 kPa was < 17 cm/s; the ability of V_max to predict fibrosis was comparable to that of the FIB4-index. Low V_max of the right portal vein was useful for identifying liver fibrosis in patients with chronic liver disease.

Noninvasive imaging of hepatic dysfunction: A state-of-the-art review

Hepatic dysfunction represents a wide spectrum of pathological changes, which can be frequently found in hepatitis, cholestasis, metabolic diseases, and focal liver lesions. As hepatic dysfunction is often clinically silent until advanced stages, there remains an unmet need to identify affected patients at early stages to enable individualized intervention which can improve prognosis. Passive liver function tests include biochemical parameters and clinical grading systems (e.g., the Child-Pugh score and Model for End-Stage Liver Disease score). Despite widely used and readily available, these approaches provide indirect and limited information regarding hepatic function. Dynamic quantitative tests of liver function are based on clearance capacity tests such as the indocyanine green (ICG) clearance test. However, controversial results have been reported for the ICG clearance test in relation with clinical outcome and the accuracy is easily affected by various factors. Imaging techniques, including ultrasound, computed tomography, and magnetic resonance imaging, allow morphological and functional assessment of the entire hepatobiliary system, hence demonstrating great potential in evaluating hepatic dysfunction noninvasively. In this article, we provide a state-of-the-art summary of noninvasive imaging modalities for hepatic dysfunction assessment along the pathophysiological track, with special emphasis on the imaging modality comparison and selection for each clinical scenario.

Predictors of early rebleeding after endoscopic therapy of first variceal bleeding in liver cirrhosis

Background

Despite the great advancement in therapeutic modalities for esophageal varices, early variceal rebleeding still occurs at high rates leading to an exaggeration of the morbidity and mortality for cirrhotic patients, so meticulous follow-up with optimum prediction and proper preventive measures for early variceal rebleeding are mandatory for increasing survival of those patients. In this respect, we evaluated the clinical, laboratory, abdominal ultrasound, and endoscopic criteria of variceal cirrhotic patients as possible risk predictors of early variceal rebleeding after endoscopic control of first variceal bleeding. All included patients were followed up blindly for 12 weeks after endoscopic control of bleeding for ascertainment of first variceal rebleeding. The demographic, clinical, laboratory, abdominal ultrasound, and upper gastrointestinal endoscopic criteria were evaluated for all patients at first admission.

Results

By univariate regression analysis, the statistically significant predictors for early variceal rebleeding were serum albumin, serum bilirubin, prothrombin concentration, Child-Pugh score, platelet count, spleen diameter, ascites, portal vein diameter and velocity, variceal size, variceal location, and red color sign. By using multivariate regression analysis, the most independent significant predictors were Child-Pugh score (sig: 0.001 and OR: 1.661), platelets count (sig: 0.000 and OR: 0.956), portal vein velocity (sig: 0.000 and OR: 0.664), variceal grading (sig: 0.000 and OR: 3.964), and variceal red color sign (sig: 0.000 and OR: 4.964). We used the multivariate regression coefficients for the significant predictors to build up early variceal rebleeding risk (EVRR) score with a significant discriminatory performance (AUC: 0.965 and sig: 0.000).

Conclusion

Child-Pugh score, platelet count, portal vein velocity, variceal grading, and variceal red color sign are independent risk predictors for early variceal rebleeding after successful control of first variceal bleeding in cirrhotic patients. Our proposed EVRR score could be helpful for the prediction of early variceal rebleeding in cirrhotic patients after endoscopic control of acute variceal bleeding; however, it should be externally validated in large prospective studies.