Measurement of hepatic vein pressure gradient in children with chronic liver diseases

Background & Aims

The aim of this study is to present our preliminary experience with Hepatic Vein Pressure Gradient (HVPG) measurements in pediatric patients with chronic liver disease.

Methods

Institutional review board approval was obtained. HVPG was measured in 20 pediatric patients, mean age 82±54months, with chronic liver disease, without extrahepatic portal vein obstruction. In nine patients the end-stage liver disease was secondary to biliary atresia; in the remaining 11, to various causes. Eleven patients had esophageal varices at endoscopy, 14 had perigastric and periesophageal collaterals at imaging scan, three had ascites, 12 had low platelet count, and all had splenomegaly.

Results

Hepatic vein catheterization was technically possible in all patients without complications. HVPG values were elevated in all but three patients, ranging between 2 and 33mmHg (mean 11.3±7.2mmHg), thus indicating a sinusoidal component in portal hypertension. A salient finding was the presence of hepatic venovenous shunts in 7 out of 9 patients with biliary atresia; however, the HVPG could still be measured distal to the shunts, but in three patients (with an HVPG of 8mmHg) it was determined in an area with a small venovenous communication still visible, therefore underestimating the actual portal pressure gradient. No venovenous shunts were detected in the non-biliary atresia patients.

Conclusions

HVPG is a feasible procedure in pediatric patients. Patients with biliary atresia very frequently have communicating vessels between hepatic veins. This hitherto unacknowledged finding can lead to the underestimation of portal pressure by HVPG measurement.

Keywords: Biliary atresia, Diagnosis, Variceal bleeding, Ascites, Pediatrics

Abbreviations: HVPG, hepatic vein pressure gradient, FHVP, free hepatic vein pressure, WHVP, wedged hepatic vein pressure, IVVS, intra-hepatic venous–venous shunts