The thoracic part of the aorta

From the thoracic part of the aorta there are two kinds of branches - parietal (parietal) and visceral (internal) branches.

Parietal (pristenochnye) branches of the thoracic part of the aorta

1. The upper diaphragmatic artery (a.phrenica superior) is paired, starts from the aorta directly above the diaphragm, goes to the lumbar portion of the diaphragm and covers its pleura.
2. The posterior intercostal arteries (aa, intercostales posteriores), paired with 10 vessels on each side, are sent to the appropriate intercostal spaces (from the third to the twelfth), blood supply to the intercostal muscles, ribs, and the skin of the breast. Each posterior intercostal artery is located at the lower edge of the overlying rib, in its furrow, between the outer and inner intercostal muscles under the same vein. The lower intercostal arteries also supply the muscles of the anterior abdominal wall.

From each posterior intercostal artery the following branches are separated: the dorsal (posterior) branch (r. Dorsalis) departs at the lower edge of the head of the rib and follows the muscles and skin of the back. It gives the spinal branch (r. Spinalis), which penetrates through a number of lying intervertebral foramen to the spinal cord, its membranes and roots of the spinal nerves, as well as the lateral cutaneous branch (r. Cutaneus lateralis) and the medial cutaneous branch (r. Cutaneus medialis), which go to the medial and lateral sections of the back. From the fourth to sixth posterior intercostal arteries, lateral and medial branches of the mammary gland (r. Mammarii mediales et laterales) also depart. The twelfth posterior intercostal artery, located beneath the lower edge of the XII rib, is called the subcostal artery (a. Subcostalis).

Visceral branches of the thoracic aorta

1. Bronchial branches (r. Bronchiales, only 2-3) go to the trachea and bronchi, anastomosing with the branches of the pulmonary artery. These branches support the walls of the bronchi and the adjacent lung tissue.
2. Esophageal branches (r. Oesophageales, only 1-5) depart from the aorta at the level from IV to VIII of the thoracic vertebra, they are directed to the walls of the esophagus. The lower esophageal branches anastomose with the branches of the left gastric artery.
3. The pericardial branches (r. Pericardiaci) follow the posterior part of the pericardium.
4. The mediastinal branches (rr. Mediastinales) supply blood to the connective tissue of the posterior mediastinum and the lymph nodes located in it.

The branches of the thoracic part of the aorta form anastomoses with arteries originating from other sources. Bronchial branches anastomose with branches of the pulmonary artery, spinal branches (from the posterior intercostal arteries) - with the same branches of the other side passing in the vertebral canal. Along the spinal cord is an anastomosis of the spinal branches that extend from the posterior intercostal arteries, and spinal branches from the vertebral, ascending cervical and lumbar arteries. Posterior intercostal arteries 3-8th anastomosed with anterior intercostal branches from the internal thoracic artery, and the posterior intercostal arteries of the 9-11th - with branches of the upper epigastric artery from the internal thoracic artery.