Endoscopic ultrasound-guided portal-systemic pressure gradient measurement.

Portal hypertension is defined by the hepatic venous pressure gradient and is measured via a percutaneous transhepatic route [1]. We describe a novel technique for direct portal pressure measurement using endoscopic ultrasound (EUS). A 27-year-old man with Noonan syndrome and congenital heart disease presented with recurrent gastrointestinal bleeding. EUS revealed an extensive network of periduodenal vessels that were attributed to congestive hepatopathy. However, bleeding continued despite cardiac surgery. Angiography failed to visualize these vessels, but the gastroduodenal artery and adjacent aberrant vessel were embolized prophylactically (●" Fig.1). Clinically significant bleeding continued leading to EUS-guided insertion of 20 coils into theperiduodenal vessels. EUSDoppler demonstrated both arterial and venous components (●" Fig.2). Follow-up imaging revealed a marked improvement of the vascular malformations (●" Fig.3a,b) with only occult, but transfusion-requiring bleeding remaining. EUSwas repeated with only one vessel large enough to allow coiling. Given continued uncertainty with regard to the prior hepatic venous pressure gradient and diagnosis, EUS was used to re-measure the portal pressure. The portal vein was accessed using a 22-gauge fine needle aspiration (FNA) needle (Wilson-Cook Medical Inc., Winston-Salem, North Carolina, United States). Portal blood was aspirated through the needle, which was connected to an arterial pressure catheter (●" Fig.4a,b,●" Fig.5a). After calibration, the portal pressure measured 11mmHg, thereby excluding significant portal hypertension. The middle hepatic vein pressure was then measured at 10mmHg (●" Fig.4c,d,●" Fig.5b), confirming a 1mmHg pressure gradient as recorded by interventional radiology. There was no evidence of bleeding and the hemoglobinwas stable 4 days later. Prior EUS-guided portal pressure measurements in porcine models correlated with percutaneous measurements [2–4]. This is the first clinical report demonstrating the feasibility and apparent safety of portal vein and hepatic vein pressure measurements by EUS, thereby allowing diagnosis of arteriovenous malformations as have been reported in Noonan syndrome [5].