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Overview of Vascular Disorders of the Liver


Whitney Jackson

, MD, University of Colorado School of Medicine

Reviewed/Revised Jan 2022 | Modified Sep 2022
Topic Resources

The liver has a dual blood supply. The portal vein (which is rich in nutrients and relatively high in oxygen) provides two thirds of blood flow to the liver. The hepatic artery (which is oxygen-rich) supplies the rest. The hepatic veins drain the liver into the inferior vena cava. When portal vein blood flow increases, hepatic artery flow decreases and vice versa (the hepatic arterial buffer response). This dual, reciprocally compensatory blood supply provides some protection from hepatic ischemia in healthy people.

Blood supply of the liver

Blood supply of the liver

Despite its dual blood supply, the liver, a metabolically active organ, can be injured by

  • Ischemia

  • Insufficient venous drainage

  • Specific vascular lesions

Insufficient venous drainage may result from focal or diffuse obstruction or from right-sided heart failure, as in congestive hepatopathy Congestive Hepatopathy Congestive hepatopathy is diffuse venous congestion within the liver that results from right-sided heart failure (usually due to a cardiomyopathy, tricuspid regurgitation, mitral insufficiency... read more . Obstruction can occur in the intrahepatic or extrahepatic veins (Budd-Chiari syndrome Budd-Chiari Syndrome Budd-Chiari syndrome is obstruction of hepatic venous outflow that originates anywhere from the small hepatic veins inside the liver to the inferior vena cava and right atrium. Manifestations... read more ) or in the intrahepatic terminal hepatic venules and hepatic sinusoids (sinusoidal obstruction syndrome Sinusoidal Obstruction Syndrome Hepatic sinusoidal obstruction syndrome is caused by endothelial injury, leading to nonthrombotic occlusion of the terminal hepatic venules and hepatic sinusoids, rather than of the hepatic... read more , previously called veno-occlusive disease) but often occurs in both. Cirrhosis Cirrhosis Cirrhosis is a late stage of hepatic fibrosis that has resulted in widespread distortion of normal hepatic architecture. Cirrhosis is characterized by regenerative nodules surrounded by dense... read more is the most common cause of diffuse intrahepatic venous outflow obstruction. Diffuse obstruction results in congestion of the sinusoids, hepatomegaly, portal hypertension Portal Hypertension Portal hypertension is elevated pressure in the portal vein. It is caused most often by cirrhosis (in North America), schistosomiasis (in endemic areas), or hepatic vascular abnormalities. Consequences... read more , reduced portal blood flow, ascites Ascites Ascites is free fluid in the peritoneal cavity. The most common cause is portal hypertension. Symptoms usually result from abdominal distention. Diagnosis is based on physical examination and... read more , and splenomegaly Splenomegaly Splenomegaly is abnormal enlargement of the spleen. (See also Overview of the Spleen.) Splenomegaly is almost always secondary to other disorders. Causes of splenomegaly are myriad, as are the... read more . Manifestations of focal venous obstruction depend on the location.

Hepatic vein disorders can result in focal or diffuse venous obstruction.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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