Bronchial arteries (Latin: arteriae bronchiales) are the main vessels that supply the bronchi and the lungs with oxygenated blood and nutrients. However, they are responsible for only 1% of the blood flow to the lungs overall.
The anatomy of bronchial arteries is quite variable, but usually, two bronchial arteries supply the left lung, while one supplies the right lung.
The bronchial arteries are located in the posterior mediastinum. They arise most commonly from the thoracic aorta (but may also arise from other vessels) at the T3 - T8 levels, most often from the T5 - T6 level. There are usually three main bronchial arteries, one on the right side and two on the left. Still, there are often additional bronchial arteries, which originate from the thoracic aorta and are usually smaller than the main ones.
The main bronchial arteries enter the lungs via the pulmonary hila and branch into smaller vessels - down to the level of the respiratory bronchioles.
Proximally, the left bronchial arteries travel to the left of the esophagus. The right bronchial artery may run to the right or the left of the esophagus.
There are usually two left bronchial arteries that typically arise directly from the descending thoracic aorta:
There is typically a single right bronchial artery. It usually originates from one of the following vessels:
The bronchial arteries provide arterial blood supply to the trachea, the bronchi, and the connective tissue of the lungs. They form anastomoses with branches of the pulmonary artery, supplying the visceral pleura on their way. Each bronchial artery also gives off a branch that supplies the middle third of the esophagus. Besides, the bronchial arteries may participate in supplying other structures within the mediastinum as well.