cardinal vein

The cardinal veins are a pair of major veins in vertebrates that transport deoxygenated blood back to the heart. They are located dorsally to the alimentary canal. The anterior cardinal veins drain the front of the body, while the posterior cardinal veins drain the rear. These veins merge to form the common cardinal veins, also known as the ducts of Cuvier, which then empty into the sinus venosus of the heart. In humans, these develop into the superior and inferior vena cavae, which are crucial for returning blood to the heart's right atrium. The development of these vessels is a complex process that occurs early in embryonic life, with significant alterations and rerouting of blood flow as the organ systems develop.123