Thoracic aorta
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Transcript of Thoracic aorta
Thoracic
aorta
By dr.aisha sadaf
Student
m.phil anatomy
Aorta
The aorta is the main arterial trunk that
delivers oxygenated blood from the left
ventricle of the heart to the tissues of the
body. It is divided for purposes of
description into the following parts:
ascending aorta, arch of the aorta,
descending thoracic aorta, and
abdominal aorta
Ascending Aorta
The ascending aorta
begins at the base of
the left ventricle
runs upward and
forward at the level
of the sternal angle,
where it becomes
continuous with the
arch of the aorta
it possesses three bulges, the sinuses of the aorta
Branches The right coronary
artery arises from the anterior aortic sinus, and the left coronary artery arises from the left posterior aortic sinus
Branches of arch of aorta
1. brachiocephalic artery, it divides into the
right subclavian and right common
carotid arteries behind the right
sternoclavicular joint.
2. left common carotid artery
3. left subclavian artery
Thoracic aorta
The thoracic aorta is contained in the
posterior mediastinal cavity.
It begins at the lower border of the fourth
thoracic vertebra where it is continuous
with the aortic arch, and ends in front of
the lower border of the twelfth thoracic
vertebra, at the aortic hiatus in the
diaphragm where it becomes the
abdominal aorta.
Continu….
At its commencement, it is situated on the left of the vertebral column; it approaches the median line as it descends; and, at its termination, lies directly in front of the column.
Relations
It is in relation, anteriorly, from above downward, with the root of the left lung, the pericardium, the esophagus, and the diaphragm; posteriorly, with the vertebral column and the azygosvein; on the right side, with the hemiazygosveins and thoracic duct; on the left side, with the left pleura and lung.
Thoracic aorta
The aorta then arches back over the right
pulmonary artery. Three vessels come out
of the aortic arch: the brachiocephalic
artery, the left common carotid artery,
and the left subclavian artery. These
vessels supply blood to the head, neck,
thorax and upper limbs
Branches of thoracic aorta
(1) VISCERAL BRANCHES
Bronchial-oesophageal artery:
Origin:
arises at the sixth thoracic vertebra from aorta-it descends over the right face of the aorta towards bifurcation of trachea and divided into bronchial anaoesophagial branches.
Bronchial Artery:
It crosses the left face of oesophagous to the bifurcation of trachea where it divides into right and left branches.Each enter into hilus of corresponding lung.
Oesophageal Artery:
The esophageal arteries four or five in number, arise from the front of the aorta, and pass obliquely downward to the esophagus, forming a chain of anastomoses along that tube, anastomosing with the esophageal branches of the inferior thyroid arteries above, and with ascending branches from the left inferior phrenic and left gastric arteries below. These arteries supply the middle third of the esophagus.
Pericardial branches
small branches of thoracic aorta
distributed to the pericardium, in the
region of the oblique pericardial sinus,
and to posterior mediastinal lymph nodes.
Mediastinal branches
The mediastinal branches are numerous
small vessels which supply the lymph
glands and loose areolar tissue in the
posterior mediastinum.
Branches of thoracic aorta
PARIETAL BRANCHES
Superior phrenic artries:
The superior phrenic arteries are small and
arise from the lower part of the thoracic
aorta; they are distributed to the posterior
part of the upper surface of the
diaphragm, and anastomose with the
musculophrenic and pericardiacophrenic
Posterior intercostal arteries The posterior intercostal arteries are arteries
that supply blood to the intercostal spaces.
There are eleven posterior intercostal arteries on each side.
The 1st and 2nd posterior intercostal arteries arise from the supreme intercostal artery, a branch of the costocervical trunk of the subclavian artery.
The lower nine arteries are the aortic intercostals, so called because they arise from the back of the thoracic aorta.
Subcostal branches
The subcostal arteries, so named because they lie below the last ribs, constitute the lowest pair of branches derived from the thoracic aorta, and are in series with the intercostal arteries.
Each passes along the lower border of the twelfth rib behind the kidney and in front of the Quadratus lumborum muscle, and is accompanied by the twelfth thoracic nerve.
The end