Azygos Veins and Thoracic Blood Drainage

The azygos system drains most of the thorax and helps return deoxygenated blood to the heart. It is part of the body’s circulatory system. The main veins in this system are the azygos vein, the hemiazygos vein, and the accessory hemiazygos vein.

The azygos vein lies just to the right of the midli...

Most of the thorax is drained by a system of veins called the azygos system, comprising the azygos, hemiazygos, and accessory hemiazygos veins.

The azygos vein, just right of the midline and in front of the vertebral column, starts at the junction of the right ascending lumbar and subcostal veins and ends in the superior vena cava.