Definition for View source for Superior vena cava

The superior vena cava (also known as the cava or cva) is a large diameter, yet short, vein that carries deoxygenated blood from the upper half of the body to the heart's right atrium. It is located in the anterior right superior mediastinum.

It is formed by the left and right brachiocephalic veins (also referred to as the innominate veins), which also receive blood from the upper limbs, eyes and neck, behind the lower border of the first right costal cartilage. The azygos vein joins it just before it enters the right atrium, at the upper right front portion of the heart. It is also known as the cranial vena cava in animals.

No valve divides the superior vena cava from the right atrium. As a result, the (right) atrial and (right) ventricular contractions are conducted up into the internal jugular vein and, through the sternocleidomastoid muscle, can be seen as the jugular venous pressure. In tricuspid valve regurgitation, these pulsations are very strong.<br>