Portal hypertension is
hypertension (high blood pressure) in the
hepatic portal system, which is composed of the
portal vein and its branches and tributaries. Portal hypertension is defined as elevation of hepatic venous pressure gradient. In clinical practice the pressure is not measured directly until the decision to place a
transjugular intrahepatic portosystemic shunt has been made. Part of the procedure, a hepatic vein wedge pressure is measured with the assumption of no pressure drop across the liver yielding portal vein pressure.