Vessel
Thoracic (descending) aorta
The descending aortic segment behind the heart
High-yield
Posterior intercostal arteries for spaces three through eleven usually arise from the descending thoracic aorta.
Overview
The descending thoracic aorta begins beyond the arch and follows the posterior mediastinum. It lies initially left of the vertebral column, approaching the midline as it reaches the diaphragm. Visceral and body-wall branches leave it along this course.
Reference facts
- Origin
- Continuation of the arch near the T4–T5 region
- Course
- Descends beside the vertebral bodies and passes through the aortic hiatus near T12
- Branches
- Posterior intercostal, subcostal, bronchial, esophageal, mediastinal, pericardial and superior phrenic branches
- Supplies
- Thoracic wall and viscera through local branches, with onward flow to abdominal and lower-body arteries
- Drains to
- Becomes the abdominal aorta at the diaphragm
Clinical correlation
Thoracic aortic disease or interruption of segmental branches can compromise downstream organs or spinal-cord perfusion. Collateral circulation and individual arterial anatomy influence that risk.
Frequently asked questions
Where does the thoracic (descending) aorta originate?
The thoracic (descending) aorta arises from the continuation of the arch near the T4–T5 region.
What does the thoracic (descending) aorta supply?
The thoracic (descending) aorta supplies the thoracic wall and viscera through local branches, with onward flow to abdominal and lower-body arteries.
Where does the thoracic (descending) aorta drain to?
The thoracic (descending) aorta drains to the becomes the abdominal aorta at the diaphragm.
What are the branches of the thoracic (descending) aorta?
Posterior intercostal, subcostal, bronchial, esophageal, mediastinal, pericardial and superior phrenic branches.