It is a vessel connectthat connects the heart to the lungs. The pulmonary artery takes blood from the heart to the lungs and the pulmonary vein takes blood from the lungs to the heart. The pulmonary vessels are the only blood vessels in the body after birth that have reversed blood flow. The pulmonary arteries actually carry deoxygenated blood to the lungs and the pulmonary veins carry oxygenated blood to the heart.