Bronchial artery labeled at center right
rami bronchiales partis thoracicae aortae
In human anatomy, the bronchial arteries supply the lungs with nutrition and 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.
The left bronchial arteries (superior & inferior) 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
- 3) any number of the right intercostal arteries mostly the third right posterior.
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 respiratory 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 oxygenated blood supplied by the bronchial arteries is returned via the pulmonary veins rather than the bronchial veins. As a consequence, blood returning to the left heart is slightly less oxygenated than blood found at the level of the pulmonary capillary beds.
Each bronchial artery also has a branch that supplies the esophagus.
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:
|pulmonary arteries||supplies deoxygenated blood pumped from the right ventricle||pulmonary circulation||relatively large|
|bronchial arteries||supplies oxygenated blood pumped from the left ventricle||systemic circulation||relatively small|
With modern surgical techniques, bronchial anastomoses heal well without bronchial artery reconnection. Largely for this reason, bronchial artery circulation is usually sacrificed during lung transplants, instead relying on the persistence of a microcirculation presumably arising from the deoxygenated pulmonary circulation to provide perfusion to the airways.
- Kauczor H, Schwickert H, Mayer E, Schweden F, Schild H, Thelen M (1994). "Spiral CT of bronchial arteries in chronic thromboembolism". J Comput Assist Tomogr. 18 (6): 855–61. doi:10.1097/00004728-199411000-00002. PMID 7962789.
- Nowak et al. Bronchial Artery Revascularization affects Graft Recovery after Lung Transplant. AJRCCM Vol 165. Number 2, Jan 2002
- Vernhet H, Bousquet C, Jean B, et al. (1999). "Bronchial aneurysms mimicking aortic aneurysms: endovascular treatment in two patients". Cardiovasc Intervent Radiol. 22 (3): 254–7. doi:10.1007/s002709900378. PMID 10382061.