Pulmonary artery

Diagram showing the pulmonary artery

The pulmonary artery is a blood vessel that connects the heart to the lungs. The pulmonary artery carries blood that does not have much oxygen. The blood from throughout the body is taken into the heart by the right atrium into the right ventricle. The blood is pumped into the pulmonary artery and into the lung capillaries. When the blood passes through the capillaries slowly to absorb the oxygen from the lungs. The oxygenated blood is taken through the pulmonary vein back into the heart through the left atrium and the left ventricle. It is then pumped throughout the body.

Anatomy

Volume rendering of a high resolution CT scan of the thorax. The anterior thoracic wall, the airways and the pulmonary vessels anterior to the root of the lung have been digitally removed to visualize the different levels of the pulmonary circulation.

The pulmonary artery is an extension of the pulmonary trunk (lat. truncus pulmonaris), extending from the right ventricle; it is located in front and to the left of all the vessels that flow in and out of the heart, and brings venous blood to the lungs (the only one of the human arteries, except for the umbilical arteries of the fetus).

The initial lobe of the pulmonary artery goes up and back and somewhat covers the beginning of the aorta. Next, lying to the left of the ascending aorta and in front of the left atrium, the pulmonary artery lies at the level of the IV thoracic vertebra under the concavity of the aortic arch. Here the pulmonary trunk is divided into:

• right branch, right pulmonary artery (lat. arteria pulmonaris dextra);
• left branch, left pulmonary artery (lat. arteria pulmonaris sinistra).

Between the initial lobe of the left branch of the pulmonary artery and the concavity of the aortic arch is the connecting tissue cord - the arterial ligament (Latin ligamentum arteriosum).

This is the remnant of the Botal duct (Latin ductus arteriosus (Botalli)), through which the fetus and blood entering the right ventricle are redirected from the pulmonary artery to the aorta: a small circle in the fetal stage of development does not function. In the future, the duct is obliterated (parallel overgrowth of the oval hole in the atrial septum).