Hepatic veins

At a glance

English

Hepatic veins

Latin (TA2)

Venae hepaticae

System

Vein

Region

Trunk

Side

Single, on the midline

About the hepatic veins

The hepatic veins return blood from the liver to the general circulation. They are the liver's outflow, whereas the portal vein and hepatic artery bring blood in. Their smallest beginnings are the central veins in the middle of each liver lobule, into which the sinusoids drain. Central veins join to form sublobular veins, and these merge step by step into the larger hepatic veins. Unlike most veins of the body, they have no valves, and they run within the liver substance without a fibrous sheath, so their walls adhere directly to the surrounding tissue.

They fall into two groups. The upper group usually consists of three large vessels, the right, middle and left hepatic veins, which drain the corresponding regions of the liver and open into the inferior vena cava just below the diaphragm. The middle and left veins often join to form a short common trunk before they reach the vena cava. The lower group is made up of a variable set of smaller veins, ranging from about six to twenty, which come mainly from the caudate and right lobes and open into the vena cava lower down, where it lies in its groove on the back of the liver.

The three main veins run between the liver's functional segments and so serve surgeons and radiologists as boundaries when they map the liver into its segments for resection. The middle hepatic vein, for example, lies roughly along the plane that divides the right and left halves of the liver.

Obstruction of hepatic venous outflow, usually by a clot, produces Budd-Chiari syndrome. Patients typically have abdominal pain, ascites and an enlarged liver, and the condition may come on suddenly or develop slowly, or cause no symptoms at all. In a transjugular intrahepatic portosystemic shunt (TIPS), a catheter passed down from the neck reaches a hepatic vein and a channel is made through the liver to a branch of the portal vein, lowering portal pressure.

Course and drainage

Begins at

Begin as the central veins of the lobules, which unite into sublobular veins and then into the hepatic veins proper.

Drains into

Open into the inferior vena cava on the posterior surface of the liver, the three large upper veins just below the diaphragm and the smaller lower veins further down.

Drains

Drain all blood that has passed through the liver sinusoids, from both portal and hepatic arterial inflow, into the inferior vena cava.