Atrium

Atrium, also auricle, in anatomy is a name given to each of the two upper cavities of the heart. These cavities are named right atrium and the left atrium. It is from these cavities blood is passed to the ventricles. The left atrium receives oxygenated blood from the pulmonary vein, while the right atrium receives deoxygenated blood from the other veins of the body.