Pulmonary circulation is the name of a route in which the pulmonary arteries and veins transport deoxygenated blood from the heart to the lungs and oxygenated blood back to the heart, respectively. The deoxygenated blood from the right ventricle does so after passing via the pulmonary artery and into the lungs for purification. Through the pulmonary vein, the left atrium receives its supply of oxygenated blood supplied by the lungs. Pulmonary circulation is the name of this route.