What Is the Thoracic Aorta?

Also known as the aortic chest (thoracic part of aorta). The descending aorta is located in the posterior mediastinum of the thoracic cavity, leveling the left side of the lower edge of the fourth thoracic vertebra, and continuing the aortic arch. The initial segment is located on the left side of the spine and gradually moves down to the front of the vertebra to reach the height of the 12th thoracic vertebra. The perforated aortic hole enters the abdominal cavity and migrates to the abdominal aorta.

Also known as the aortic chest (thoracic part of aorta). The descending aorta is located in the posterior mediastinum of the thoracic cavity, leveling the left side of the lower edge of the fourth thoracic vertebra, and continuing the aortic arch. The initial segment is located on the left side of the spine and gradually moves down to the front of the vertebra to reach the height of the 12th thoracic vertebra. The perforated aortic hole enters the abdominal cavity and migrates to the abdominal aorta.

Chinese name

Thoracic aorta

Foreign name

thoracic aorta

Concept

Thoracic aorta

Branch

Visceral branch wall branch

Connect

Thoracic aorta

Thoracic aorta I. Overview:

The front of the thoracic aorta is adjacent to the left lung root, left atrium, pericardium, and esophagus from top to bottom. At the beginning, the esophagus is on the right side of the thoracic aorta, and the 8th to 9th thoracic vertebrae are turned across the front to the left. The back is adjacent to structures such as the semi-odd vein and spine, and the right is adjacent to the thoracic duct, right lung, and right pleura. The left side is adjacent to the left lung and left pleura.

There are two branches of the thoracic aorta along the way: visceral branch and wall branch. Visceral branches are relatively small, mainly including the pericardial branch, bronchial artery and esophageal artery. It is distributed in pleural organs such as pericardium, bronchus, lung and esophagus.

The wall branches include the superior iliac artery, mediastinal artery, and intercostal artery, which are mainly distributed in the superior iliac crest, mediastinum, and chest wall. There are 10 pairs of intercostal arteries, and the upper 9 pairs run in the 3 to 11 intercostal space. The first and second intercostal spaces are branched from the costal neck stem. For the subcostal artery. Each intercostal artery is divided into two branches, the posterior branch is small, and is distributed in the back muscles, skin and spinal cord and their capsules. The anterior branch is the main trunk of the intercostal artery. It travels between the internal and external muscles of the intercostal space and branches out along the way to the intercostal muscles, skin, and breasts. The anterior branches of the next few intercostal arteries also penetrate the intercostal space at the costal arch to the anterior lateral wall of the abdomen.

Thoracic aorta

The main causes are atherosclerosis, syphilis, congenital, traumatic and fungal. The ratio of thoracic aortic aneurysms to abdominal aortic aneurysms was 10: 1. The age of onset is more than 40 years old.

[X-ray performance]

The smooth or sharp fusiform or sacral part of the edge protrudes into shadow, which is closely connected to the aortic wall and cannot be separated. Some aneurysms can adhere to the pleura and have rough edges; most of them are uniform in density. If the aneurysm is nodular or multiple aneurysms overlap, the density of the aneurysm wall or thrombus can be uneven; Linear or arc-shaped, the calcification of thrombus calcified inside the aneurysm wall is irregular; the aneurysm often shows systolic systolic pulsation; the aortic aneurysm can compress the trachea, bronchus and esophagus; The skeletal muscle caused compressive damage; the phrenic nerve was compressed and the diaphragm was paralyzed, and the diaphragm was elevated. Heart shape and size are generally unchanged. When the aortic aneurysm is located above the aortic valve and the aortic valve is not fully closed, the left ventricle can be enlarged.

[Arteriographic manifestations]

Aortic angiography is a reliable method for clear diagnosis. The aortic aneurysm can be directly developed by angiography, showing the shape and size of the tumor and the relationship between the aorta and surrounding blood vessels; the angiography can find small aneurysms located in the mediastinum that cannot be found by general examination; organic thrombus in the aneurysm At this time, the tumor may not be visualized or only partially visualized during arteriography. The thrombus appears as a filling defect.

[CT performance]

On CT, fusiform, cystic, or irregular protrusions can be seen next to the thoracic aorta. What you see on multiple levels is closely connected to the aortic wall and cannot be separated. Ascending aorta and aortic arch are more common, followed by descending aorta. Arc calcification of the aneurysm wall is sometimes seen. After injection of the contrast agent, the aorta was dilated and the enhancement was obvious, but the local mural thrombus was not significantly enhanced, forming a corresponding low-density area, which is a typical CT sign of aortic aneurysm.