Noninvasive Subharmonic Aided Pressure Estimation of Portal Hypertension; Renewal

Overview

This is an open-label, non-randomized trial that will be conducted at three clinical sites, Thomas Jefferson University (TJU), the Hospital of the University of Pennsylvania (HUP) and University of Bern (UB). Enrollment will be allocated into one of 4 different cohorts depending on the inclusion criteria for each cohort. Cohort 1: Patients scheduled for hepatic vein pressure gradient (HVPG) measurements will subsequently undergo two consecutive SHAPE (subharmonic aided pressure estimation) procedures using different ultrasound contrast agents (Definity \[Lantheus Medical Imaging, N Bilerica, MA, USA\] and Sonazoid \[GE Healthcare, Oslo, Norway\] in randomized order) to estimate portal pressures with a Logiq E10 scanner (GE Healthcare, Waukesha, WI, USA) and determine the reproducibility of the SHAPE algorithm. Cohort 2: Patients identified as having clinically significant portal hypertension (CSPH) will be monitored by SHAPE with Sonazoid for the duration of this project (18-24 months on average). These subjects will have follow-up ultrasound scans every 6 ± 2 months to check for hepatocellular carcinoma (HCC) (using the Barcelona-Liver Cancer staging system) as well as ascites and at those times a repeat SHAPE examination will be performed. Liver stiffness values will be measured with elastography as well. This cohort will examine if serial SHAPE can accurately predict development of ascites and other liver related events in patients with compensated cirrhosis undergoing routine HCC surveillance in a multi-center setting. Cohort 3: Subjects newly diagnosed with portal hypertension and starting treatment with non-selective β-blockers will be monitored with SHAPE and results compared to elastography measurements of liver stiffness with standard assessments (e.g., serum liver function tests and measurement of spleen size as well as platelet count). This cohort will establish if SHAPE can be used to monitor treatment response in patients identified with portal hypertension. Cohort 4: Patients with compensated advanced chronic liver disease scheduled for an endoscopy examination for screening of varices relative to the Baveno VI and the expanded-Baveno VI criteria as well as the AST to Platelet Ratio Index will undergo a SHAPE examination. This cohort will compare the predictive ability of SHAPE for allocating patients with compensated advanced chronic liver disease to screening of varices compared to the current standard of care.

For each SHAPE study (Cohorts 1, 2, 3 and 4), a dose of three vials with 60 μL of Sonazoid microbubbles (6 mL) will be prepared. An infusion of Sonazoid (1.44 μL microbubbles/kg/hour) and saline (120 mL/hour) through an IV line in the antecubital vein (or, if need be, in another suitable vein) will be started. The duration of contrast agent infusion will range from 6 to 10 minutes. For the direct contrast agent comparison in Cohort 1, two vials of Definity will be mixed and diluted in 50 mL of normal saline, yielding a concentration of 49.4 μL/mL, and infused over approximately 10-12 minutes. A waiting period of at least 30 minutes will be observed in Cohort 1 between infusing contrast agents and the order of the contrast agents will be randomized. Once the infusion of contrast has started, ultrasound imaging will be performed with the C1-6-D curvi-linear array (GE Healthcare) to guide SHAPE ROI placement into the portal vein (while also visualizing a hepatic vein). The SHAPE optimization algorithm will be activated and the acoustic power will be adjusted to produce the maximum change in subharmonic amplitudes (i.e., maximizing the sensitivity of SHAPE). Subharmonic raw DICOM data from the microbubbles (i.e., SHAPE) will be acquired at the optimal acoustic power setting in 5 s segments during the infusion of the Sonazoid (or Definity) suspension. All measurements will be repeated three times to allow for averaging of the resulting SHAPE pressure estimates. The SHAPE pressure estimates will be calculated on the Logiq E10 and recorded. Finally, all digital clips will be transferred off-line for backup and to permit repeat calculations of the portal pressure estimates in case new processing parameters are developed as part of this study.