In human anatomy, the descending aorta is part of the aorta, the largest artery, situated in the chest. It is the continued portion of the aorta immediately following the aortic arch.
| Descending aorta | |
|---|---|
 Plan of the branches. | |
 The thoracic aorta, viewed from the left side. | |
| Details | |
| Precursor | Dorsal aorta |
| Source | Ascending aorta |
| Branches | Thoracic aorta Abdominal aorta |
| Identifiers | |
| Latin | aorta descendens, pars descendens aortae |
| TA98 | A12.2.10.001 |
| TA2 | 4185 |
| FMA | 3784 |
| Anatomical terminology | |
The descending aorta begins at the aortic arch and runs down through the chest and abdomen. The descending aorta anatomically consists of two portions or segments, the thoracic and the abdominal aorta, in correspondence with the two great cavities of the trunk in which it is situated. Within the abdomen, the descending aorta branches into the two common iliac arteries which serve the pelvis and, eventually, the legs.
The ductus arteriosus connects to the junction between the pulmonary artery and the descending aorta in foetal life. This artery later regresses as the ligamentum arteriosum.[1][2]
Structure
editMain article: Aorta
The descending aorta is made up of multiple parts that extend from the chest to the abdomen. The specific name changes depending on location. The descending thoracic aorta becomes the descending abdominal aorta once it reaches the diaphragm. It is preceded by the ascending aorta.
The descending aorta is composed of three layers. The inner layers is the tunica intima which regulates blood pressure. The middle layers is the media, which moves blood in one direction. The outer layer is the adventitia which provides structure and support.[3]
Diameter of the descending aorta varies largely based on sex and age.
Function
edit
The aorta transports oxygenated blood from the heart to the entire body.[4] As the aorta descends down the body, it branches into smaller arteries. The descending thoracic aorta branches into the following (descending order)
- Bronchial arteries
- Esophageal arteries
- Mediastinal arteries
- Pericardial arteries
- Superior phrenic arteries
The branches of the descending abdominal aorta include (descending order)
Clinical significance
editAortic aneurysms are the most common condition of the descending aorta. Aortic aneurysms are a bulge or swelling of the aorta due to a weak spot. A thoracic aortic aneurysm (TAA) is an aortic aneurysm occuring in the upper part of the descending aorta. An abdominal aortic aneurysm (AAA) is the most common kind of aortic aneurysm, occuring in the descending abdominal aorta. A thoracoabdominal aneurysm (TAAA) is an aneurysm that extends from the descending thoracic aorta to the descending abdominal aorta.[3]
See also
editReferences
editThis article incorporates text in the public domain from page 598 of the 20th edition of Gray's Anatomy (1918)
- ^ Rubin, Raphael; Strayer, David S., eds. (2008). Rubin's Pathology: Clinicopathologic Foundations of Medicine (5th ed.). Philadelphia: Lippincott Williams & Wilkins. p. 442. ISBN 9780781795166.
- ^ Naidich, David P.; Webb, W. Richard; et al., eds. (2007). Computed Tomography and Magnetic Resonance of the Thorax (4th ed.). Philadelphia: Lippincott Williams & Wilkins. p. 100. ISBN 9780781757652.
- ^ a b "What Is the Descending Aorta?". Cleveland Clinic. Archived from the original on 2025-06-13. Retrieved 2025-12-03.
- ^ "Aorta anatomy - UF Health". ufhealth.org. Retrieved 2024-12-06.
External links
edit- Anatomy figure: 19:04-03 at Human Anatomy Online, SUNY Downstate Medical Center – "Left side of the mediastinum."
