AnatoMemory

Vessel

Pulmonary arteries

Paired inflow vessels for the lungs

ThoraxCardiovascular system

High-yield

Use the main bronchus as the reference: right pulmonary artery anterior; left pulmonary artery superior.

Overview

Each lung receives a pulmonary artery from the pulmonary trunk. At the hilum the right artery is in front of the main bronchus, whereas the left artery lies above it. Smaller arterial branches distribute blood through the lobes and bronchopulmonary segments.

Reference facts

Origin
Right and left divisions of the pulmonary trunk below the aortic arch
Course
Right: behind ascending aorta and superior vena cava, in front of right main bronchus. Left: above left main bronchus and in front of descending aorta
Branches
Lobar, segmental and smaller intrapulmonary arterial branches
Supplies
Alveolar capillary networks, receiving relatively deoxygenated blood from the right ventricle
Drains to
Blood passes through lung capillaries before returning by pulmonary veins to the left atrium

Clinical correlation

Pulmonary emboli may raise right ventricular afterload. A saddle-shaped clot can be dangerous, but its shape alone does not establish shock or determine the degree of right ventricular dysfunction.

Frequently asked questions

Where do the pulmonary arteries originate?

The pulmonary arteries arise from the right and left divisions of the pulmonary trunk below the aortic arch.

What do the pulmonary arteries supply?

The pulmonary arteries supply the alveolar capillary networks, receiving relatively deoxygenated blood from the right ventricle.

Where do blood from the pulmonary arteries go?

The pulmonary arteries drain to the blood passes through lung capillaries before returning by pulmonary veins to the left atrium.

What are the branches of the pulmonary arteries?

Branches of the pulmonary arteries include the lobar, segmental and smaller intrapulmonary arterial branches.