Arising directly from the aorta, the bronchial arteries supply the lungs with oxygenated blood. There are usually two bronchial arteries which travel to the left lung, and one to the right lung as they ramify with the bronchial tree in relation to the posterior aspect of the respective bronchi. The bronchial arteries form capillaries which are continuous with either the pulmonary or bronchial veins. When inflammation and thrombosis of the bronchial arteries occurs, there will be a gradual reactive enlargement of the bronchial tree, which may be associated with massive hemoptysis.
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 respiratory bronchioles. They anastomose with the branches of the pulmonary arteries, and together, they supply the visceral pleura of the lung in the process. Much of the blood supplied by the bronchial arteries is returned via the pulmonary veins rather than the bronchial veins. Each bronchial artery also has a branch that supplies the esophagus.