Correlation of Liver and Spleen Stiffness by RT-2D-SWE and Severity of Portal Hypertension by HVPG

Correlation of Liver and Spleen Stifness as Assesed by Real Time 2-Dimensional Shear Wave Elastography With Severity of Portal Hypertension and Clinical Outcomes in Patients With Compensated Advanced Chronic Liver Disease

Portal hypertension (PH) results from the increase of portal flow resistance in fibrotic tissue of the liver in patients with chronic liver diseases, leading to complications such as varices formation and variceal bleeding, ascites formation, spleenomegaly and hypersplenismus, systemic haemodynamic disorders and porto-systemic shunts formation. Early detection of PH in patients with chronic liver diseases is clinically important as it should change patient management in order to prevent the formation/onset or recurrence of PH complications. Hepatic venous pressure gradient (HVPG) measurement is the gold standard for the assessment of the severity of PH. However, it is an invasive method with its risks, and relatively costly. On the other hand transient elastography (TE) emerged as a non-invasive, easy, safe and low cost method with the potential to assess the severity of PH, as liver stiffness (LS) and spleen stiffens (SS) measured by TE showed very good correlation with HVPG. Real-time 2D shear wave elastography (RT-2D-SWE) is an ultrasound elastography method reliable for non-invasive assessment of fibrosis stage especially in chronic viral hepatitis, but only preliminary data exist on the correlation of RT-2D-SWE measured LS/SS with and HVPG. In this study we hypothesized that LS and SS measured by RT-2D-SWE correlate with HVPG enabling RT-2D-SWE to be used for the assessment of severity of PH. The primary aim of this study is to analyse correlation between LS and SS as assessed by RT-2D-SWE and TE with the grade of portal hypertension as assessed by HVPG. The secondary aims are: 1) to analyse clinical outcomes of these patients in order to determine if LS and/or SS as assessed by RT-2D-SWE might predict adverse outcomes (liver decompensation, death or HCC development), and 2) to compare clinical performance (AUC) of RT-2D-SWE and TE for the assessment of the PH severity as well as for predicting clinical outcomes. Patients with suspicion of having compensated advanced chronic liver disease (cACLD) as assesed by non-invasive methods (transabdominal ultrasound, laboratory findings, FIB-4 and APRI score, and LS measurements by TE), will be included. Since positive predictive value of non-invasive methods for cirrhosis is generally not very reliable, these patients will be offered transjugular liver biopsy and HVPG measurements as gold-standard methods to define the stage of liver disease and severity of PH. These patients will undergo LS and SS measurements by RT-2D-SWE on Aixplorer SuperSonic Imagine ultrasound system and HVPG measurements as well, with transjugular liver biopsy performed during the same session. After SWE™ and HVPG measurement, 5-year follow-up is planned, including standard surveillance: laboratory findings, transabdominal US every six months and upper-GI endoscopy according to relevant guidelines, as well as treatment according to relevant guidelines as indicated: beta blockers, endoscopic variceal ligation, etiologic treatment and dietary measures. Appropriate statistical analysis will be undertaken after the enrollment period, as well as after follow-up period.

Inclusion Criteria:

• patients with suspicion of having cACLD as assessed by transabdominal ultrasound, laboratory findings, FIB-4 and/or APRI score, and/or LS measurements
• patients with chronic liver disease in whom any extrahepatic surgical procedure is planned and in whom it was not possible to exclude cACLD and/or portal hypertension based on non-invasive procedures only
• patients with HCC or other liver tumors on the ground of presumed liver cirrhosis who are under consideration for surgical resection, in whom HVPG is performed in order to reliably exclude clinically significant portal hypertension
• compliance to the study protocol
• signed approval for the diagnostic ultrasound with SWE™ and for transjugular liver biopsy and HVPG measurement

Exclusion Criteria:

• elevated alanine aminotransferase (ALT) values > 5 x upper limit of normal (ULN)
• obstructive jaundice
• congestive heart failure
• sepsis
• thrombosis of right jugular vein
• thrombosis of hepatic veins
• hydatid cyst
• cholangitis
• absence of cooperation
• pregnancy