The hepatic veins are the carriers of deoxygenated blood that comes via the liver, and then drain it into the inferior vena cava. They are also the carriers of blood that has been drained from the colon, pancreas, small intestine, and the stomach, and cleaned by the liver. These veins originate from the core vein of the liver lobule, but they do not have any valve. These veins can be segregated into the lower group and the upper group veins. The lower group veins originate from the right lobe, are relatively smaller in size than the upper group veins, and vary in numbers. The upper group veins, on the other hand, originate from the backside of the liver, and drain into the left lobe. The deoxygenated blood from these veins into the inferior vena cava is delivered back to the heart, where the re-oxygenation process of the blood takes place. In that respect, the liver performs the role of a cleaning organ when the blood is on its way back to the heart. Any impediment in the outflow of blood from the hepatic veins may result in a serious condition known as Budd-Chiari syndrome.
Written and medically reviewed by the Healthline Editorial Team
In Depth: Hepatic veins