Pulmonary vein three and five in the healthy population. The two left lobar veins may be united as a single pulmonary vein in about 25% of people; the two right veins may be united in about 3%. The pulmonary veins play an essential role in respiration, by receiving blood that has been oxygenated in the alveoli and returning it to the left atrium. As part of the pulmonary circulation they carry oxygenated blood back to the heart, as opposed to the veins of the systemic circulation which carry deoxygenated blood. A rare genetic defect of the pulmonary veins can cause them to
Femoral vein has led some physicians to falsely conclude it is a superficial vein, which has resulted in patients (with deep vein thrombosis) being denied efficacious anticoagulant or thrombolytic therapy. Femoral vein In the human body, the femoral vein is a blood vessel that accompanies the femoral artery in the femoral sheath. It begins at the adductor canal (also known as "Hunter's canal") and is a continuation of the popliteal vein. It ends at the inferior margin of the inguinal ligament, where it becomes the external iliac vein. The femoral vein bears valves which are mostly bicuspid and whose number is variable