An abnormal balloon- or sac-like dilatation in the wall of the THORACIC AORTA. This proximal descending portion of aorta gives rise to the visceral and the parietal branches above the aortic hiatus at the diaphragm.

Synonyms: Aneurysms, Thoracoabdominal Aortic, Aortic Aneurysm, Thoracic, Aortic Aneurysms, Thoracic, Thoracoabdominal Aortic Aneurysms, Thoracoabdominal Aortic Aneurysm, Aneurysm, Thoracoabdominal Aortic, Aneurysm, Thoracic Aortic, Thoracic Aortic Aneurysms, Thoracic Aortic Aneurysm, Aortic Aneurysm, Thoracoabdominal, Aortic Aneurysms, Thoracoabdominal