Endoscopic Ultrasound-Guided Portal Pressure Gradient (PPG) Measurement: A Simplified Novel Technique Using 25-Gauge FNA Needle With Compact Transducer Versus Standard Transjugular Approach: A Comparative Animal Study: Presidential Poster

Abstract

Introduction: Portal hypertension (PH) is a serious complication of liver cirrhosis. The hepatic venous pressure gradient (HVPG) accurately reflects the degree of PH and is the single best prognostic factor in liver disease. HVPG can guide medical therapy and predict liver decompensation as well as cancer risk. Currently, measurement of PPG is performed using an invasive transjugular approach requiring radiation and IV contrast; and it provides only an indirect measurement. We present the first study of a novel, simple EUS-guided system using a 25g FNA needle and compact manometer to directly measure PPG with simultaneous comparison to the standard transjugular method. Methods: Experiments were performed in 3 swine under general anesthesia. Baseline and portal hypertensive venous manometry was performed. The PH model was created by rapid Dextran-40 infusion. Using a linear echoendoscope, a 25g FNA needle with attached manometer was used to puncture (transgastric-transhepatic approach) and measure pressures in the portal vein (PV), right hepatic vein (RHV), and inferior vena cava (IVC). Pressure measurements in the aorta were also performed. Manometric data was obtained from the RHV (free and wedged), IVC and aorta with an occlusion balloon. All EUS and transjugular manometric data were captured simultaneously, in real time, at each corresponding vessel. Pressure correlation was divided into three groups; low pressure (baseline), medium pressure (PH model) and high pressure (arterial). Scatter plots and Pearson's correlation coefficient (R) were used. Results: EUS identification, access and manometry were successful in all targeted vessels. There was excellent correlation between EUS and transjugular approach at all pressure ranges. R co-efficient was 0.99 (Arterial, venous-graph 1), 0.986 (all veins-graph 2) and 0.985 (PV+HV only-graph 3). No adverse event occurred despite repeated vascular punctures. No bleeding was seen at EUS or on fluoroscopy, despite presence of PH. Necropsy was not performed.Figure 1Figure 2Figure 3Conclusion: This novel technique of EUS-PPG measurement using a 25G needle and novel manometer was feasible and demonstrated excellent correlation with the standard transjugular method throughout low, medium and high pressure ranges. There were no adverse events acutely. Clinical trials are currently underway.