Science, Tech, Math › Science Pulmonary Veins Share Flipboard Email Print Heart Image. © MedValet Science Biology Physiology Basics Cell Biology Genetics Organisms Anatomy Botany Ecology Chemistry Physics Geology Astronomy Weather & Climate by Regina Bailey Regina Bailey is a science writer and educator. Her work has been featured in "Kaplan AP Biology" and "The Internet for Cellular and Molecular Biologists." Updated March 06, 2017 Definition: Veins are vessels that bring blood to the heart. Pulmonary veins carry oxygenated blood from the lungs to the left atrium. There are four pulmonary veins which extend from the left atrium to the lungs. They are the right superior, right inferior, left superior, and left inferior pulmonary veins. Continue Reading