The inferior vena cava carries blood from the lower half of the body whilst the superior vena cava carries blood from the upper half of the body.It is formed by the joining of the right and the left common iliac veins, usually at the level of the fifth lumbar vertebra.he inferior vena cava (or IVC) (Latin: vena, vein, cavus, hollow), is one of the venae cavae, two large veins, that carries deoxygenated blood from the body into the right atrium of the heart.