Objective: The purpose of this study was to identify threshold right and left portal vein sonographic velocities that are correlated with subsequent development of hepatofugal flow in the main portal vein (MPV), a marker of portal hypertension.
Methods: A database containing 6019 Doppler liver ultrasound reports from an academic hospital was parsed using a Visual Basic computer algorithm. Right and left portal vein velocities were identified from 65 patients who developed hepatofugal MPV flow. Patients with a liver transplant or transjugular intrahepatic portosystemic shunt were excluded. Similarly, right and left portal vein velocities were identified from 195 patients free of chronic hepatic disease. The right and left portal vein velocities of these 2 groups were analyzed using a receiver operating characteristic curve to identify threshold velocities with the optimal sensitivity and specificity for patients who will develop hepatofugal flow in the MPV.
Results: A threshold velocity of 11 cm/s in the right portal vein is associated with 81.8% sensitivity and 93.5% specificity in distinguishing patients who develop hepatofugal flow from otherwise healthy control subjects. Likewise, a threshold velocity of 8 cm/s in the left portal vein is associated with a 62.3% sensitivity and a 94.5% specificity.
Conclusions: A threshold right portal vein velocity of 11 cm/s can be used with high sensitivity and specificity to identify patients who may develop hepatofugal flow in the MPV. A left portal vein velocity less than 8 cm/s is 94.5% specific for the development of hepatofugal flow.