Bronchial artery

In human anatomy, the bronchial arteries help supply the lungs with oxygenated blood. Although there is much variation, there are usually two bronchial arteries that run to the left lung, and one to the right lung.

Origin
The left bronchial arteries usually arise directly from the thoracic aorta.

The single right bronchial artery usually arises from one of the following:
 * 1) the thoracic aorta at a common trunk with the right 3rd posterior intercostal artery
 * 2) the superior bronchial artery on the left side

Distribution to lung
The bronchial arteries supply blood to the bronchi and connective tissue of the lungs. They travel with and branch with the bronchi, ending about at the level of the repiratory bronchioles. They anastomose with the branches of the pulmonary arteries, and together, they supply the visceral pleura of the lung in the process.

Note that much of the blood supplied by the bronchial arteries is returned via the pulmonary veins rather than the bronchial veins.

Comparison with pulmonary arteries
It is easy to confuse the bronchial arteries with the pulmonary arteries, because they both supply the lungs with blood, but there are important differences:

Pathology
The bronchial arteries are typically enlarged and tortuous in chronic pulmonary thromboembolic hypertension.