What is the normal Doppler waveform signature of the hepatic veins?

The normal hepatic vein Doppler waveform is triphasic, reflecting cardiac cycle variations in central venous pressure transmitted from the right atrium through the IVC. Loss of triphasicity may suggest elevated right atrial pressures or hepatic venous obstruction.

According to Rumack’s Diagnostic Ultrasound:

“The normal hepatic vein waveform is triphasic due to transmitted right atrial pressure variations.”