Superior lobar artery of right lung

At a glance

English

Superior lobar artery of right lung

Latin (TA2)

Arteria lobaris superior pulmonis dextri

System

Artery

Region

Trunk

Side

Single, on the midline

About the superior lobar artery of right lung

The right pulmonary artery runs to the right beneath the arch of the aorta and behind the superior vena cava to reach the hilum of the right lung. Even before it enters the lung it gives off its first large branch, the superior lobar artery, often called the truncus anterior. The rest of the vessel then continues downwards as the interlobar part.

At the right hilum the upper lobe bronchus leaves the main bronchus above the level of the pulmonary artery, which is why it is called eparterial. The superior lobar artery therefore runs up in front of and below this bronchus to reach the upper lobe. It soon divides into segmental branches for the apical and anterior segments, and often for part of the posterior segment. A separate posterior ascending artery from the interlobar part usually completes the supply of the posterior segment.

Each segmental artery runs with its segmental bronchus and divides with it down to the alveolar capillaries, delivering deoxygenated blood from the right ventricle for gas exchange. The pulmonary veins, in contrast, drain between segments.

The superior lobar artery is short and wide and lies at the front of the hilum, close to the superior pulmonary vein. In right upper lobectomy it is usually the first vessel dissected and divided, and its short course means that a tear can bleed heavily. The variable posterior ascending branch must be looked for separately, or it may be left behind or injured.

Course and supply

Arises from

The right pulmonary artery, as its first branch, at or just outside the right hilum.

Ends in

Divides into the segmental arteries of the apical, anterior and part of the posterior segments of the right upper lobe.

Supplies

Carries deoxygenated blood to the right upper lobe for gas exchange.