pulmonary artery (right, anatomy)

Last reviewed 01/2018

The right pulmonary artery originates at the division of the pulmonary trunk anterior to the left main bronchus. It is longer than the left main pulmonary artery. For a short distance it is ensheathed within the pericardium as it passes laterally and slightly inferiorly within the pericardial sac. Its relations within the right lung root are:

  • posterior and superior:
    • right principal bronchus
    • oesophagus
  • superior:
    • medially: carina
    • laterally: right azygous vein arching over to superior vena cava
  • anterior:
    • laterally: superior vena cava
    • medially: arch of aorta

About a centimetre distal to its origin within the lung root, the right pulmonary artery gives off its first branch to the superior lobe. This passes superolaterally in tandem with the superior lobe bronchus.

At the hilum, the main branch of the right pulmonary artery continues inferiorly. Within the hilum, it is anterior to the bronchi and superoposterior to the veins. It gives off branches to the middle lobe at the intersection of oblique and horizontal fissures within the lung parenchyma. Finally, it continues inferiorly to supply the segments of the right inferior lobe.

The pulmonary artery ramifies with the bronchial tree eventually to form capillaries within the walls of individual alveoli.