Portal hypertension

Portal hypertension is abnormally elevated pressure in the portal venous system, which carries blood from the digestive organs and spleen to the liver. It commonly results from resistance to blood flow through the liver.

Portal venous system: The veins that drain the digestive organs, spleen, pancreas, and gallbladder into the liver. This is the vascular network in which pressure becomes abnormally elevated.
Hepatic portal vein: The large vein that carries nutrient-rich blood from abdominal organs into the liver. It is the main inflow vessel whose pressure reflects the portal circulation.
Cirrhosis: Advanced liver scarring with regenerative nodules that disrupt normal liver architecture. It is the most common cause of portal hypertension in many populations.
Prehepatic portal hypertension: Portal hypertension caused by obstruction or increased resistance before blood enters the liver. It contrasts with intrahepatic disease because the resistance lies upstream of the liver.
Hepatic stellate cell: A liver cell that stores vitamin A and can become contractile and fibrogenic after injury. Its activation increases intrahepatic resistance by promoting fibrosis and vessel constriction.
Hepatic sinusoids: Specialized low-pressure vascular channels between liver cell plates. Resistance across these channels is a major determinant of intrahepatic portal pressure.
Baveno VII: An international consensus on diagnosing and managing portal hypertension and varices in chronic liver disease. Its criteria guide noninvasive assessment and preventive treatment.
Intrahepatic portal hypertension: Portal hypertension caused by resistance within the liver’s vascular or parenchymal structures. This is the usual anatomical pattern in cirrhosis.
Portosystemic shunt: A vascular connection that diverts blood between the portal circulation and systemic veins. Collateral shunts form as portal blood seeks routes around high resistance.
Hepatic venous pressure gradient: The difference between wedged and free hepatic venous pressures, used to estimate sinusoidal portal pressure. This is the standard indirect measurement for many forms of portal hypertension.

Linked from 12 pages