The brachiocephalic artery, brachiocephalic trunk, or innominate artery is an

artery An artery () is a blood vessel in humans and most other animals that takes oxygenated blood away from the heart in the systemic circulation to one or more parts of the body. Exceptions that carry deoxygenated blood are the pulmonary arteries in ...

of the

mediastinum The mediastinum (from ;: mediastina) is the central compartment of the thoracic cavity. Surrounded by loose connective tissue, it is a region that contains vital organs and structures within the thorax, mainly the heart and its vessels, the eso ...

that supplies blood to the right

arm In human anatomy, the arm refers to the upper limb in common usage, although academically the term specifically means the upper arm between the glenohumeral joint (shoulder joint) and the elbow joint. The distal part of the upper limb between ...

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple ani ...

, and

neck The neck is the part of the body in many vertebrates that connects the head to the torso. It supports the weight of the head and protects the nerves that transmit sensory and motor information between the brain and the rest of the body. Addition ...

. It is the first branch of the

aortic arch The aortic arch, arch of the aorta, or transverse aortic arch () is the part of the aorta between the ascending and descending aorta. The arch travels backward, so that it ultimately runs to the left of the trachea. Structure The aorta begins ...

. Soon after it emerges, the brachiocephalic artery divides into the right

common carotid artery In anatomy, the left and right common carotid arteries (carotids) () are artery, arteries that supply the head and neck with oxygenated blood; they divide in the neck to form the external carotid artery, external and internal carotid artery, inte ...

and the right

subclavian artery In human anatomy, the subclavian arteries are paired major arteries of the upper thorax, below the clavicle. They receive blood from the aortic arch. The left subclavian artery supplies blood to the left arm and the right subclavian artery suppli ...

. There is no brachiocephalic artery for the left side of the body. The left common carotid artery and the left subclavian artery come directly off the aortic arch. Despite this, there are two

brachiocephalic vein The left and right brachiocephalic veins (previously called innominate veins) are major veins in the Thorax, upper chest, formed by the union of the ipsilateral internal jugular vein and subclavian vein (the so-called venous angle) behind the ster ...

Structure

The brachiocephalic artery arises on a level with the upper border of the second right

costal cartilage Costal cartilage, also known as rib cartilage, are bars of hyaline cartilage that serve to prolong the ribs forward and contribute to the elasticity of the walls of the thorax. Costal cartilage is only found at the anterior ends of the ribs, pr ...

from the start of the

on a plane anterior to the origin of the left

carotid artery Carotid artery may refer to: * Common carotid artery, often "carotids" or "carotid", an artery on each side of the neck which divides into the external carotid artery and internal carotid artery * External carotid artery, an artery on each side of ...

. It ascends obliquely upward, backward, and to the right to the level of the upper border of the right sternoclavicular articulation, where it divides into the right

and right subclavian arteries. The artery then crosses the

trachea The trachea (: tracheae or tracheas), also known as the windpipe, is a cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all animals' lungs. The trachea extends from ...

in front of it obliquely from the left to the right, roughly at the middle of the trachea or the level of the ninth tracheal cartilage.

Relations

The brachiocephalic artery has relation with: * ''anterior'' - left

and thymus * ''posterior'' - trachea * ''right'' -

superior vena cava The superior vena cava (SVC) is the superior of the two venae cavae, the great venous trunks that return deoxygenated blood from the systemic circulation to the right atrium of the heart. It is a large-diameter (24 mm) short length vei ...

, right brachiocephalic vein, and

pleura The pleurae (: pleura) are the two flattened closed sacs filled with pleural fluid, each ensheathing each lung and lining their surrounding tissues, locally appearing as two opposing layers of serous membrane separating the lungs from the med ...

* ''left'' - left common carotid artery and thymus The

thymus The thymus (: thymuses or thymi) is a specialized primary lymphoid organ of the immune system. Within the thymus, T cells mature. T cells are critical to the adaptive immune system, where the body adapts to specific foreign invaders. The thymus ...

typically sits atop the brachiocephalic artery, and it separates the artery from the posterior surface of the

manubrium The sternum (: sternums or sterna) or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, human lung, lungs, and ma ...

sternum The sternum (: sternums or sterna) or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major bl ...

Branches

The thyroid ima artery ascends in front of the trachea to the lower part of the

thyroid The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans, it is a butterfly-shaped gland located in the neck below the Adam's apple. It consists of two connected lobes. The lower two thirds of the lobes are connected by ...

, which it supplies.

Variation

The innominate artery usually gives off no branches, but occasionally a small branch, the thyroid ima artery, arises from it. Other times, it gives off a thymic or bronchial branch. Thyroid ima artery varies greatly in size, and appears to compensate for deficiency or absence of one of the other thyroid vessels. It occasionally arises from the

aorta The aorta ( ; : aortas or aortae) is the main and largest artery in the human body, originating from the Ventricle (heart), left ventricle of the heart, branching upwards immediately after, and extending down to the abdomen, where it splits at ...

, the

right common carotid In anatomy, the left and right common carotid arteries (carotids) () are arteries that supply the head and neck with oxygenated blood; they divide in the neck to form the external and internal carotid arteries. Structure The common carotid a ...

, the subclavian or the

internal mammary The internal thoracic artery (ITA), also known as the internal mammary artery, is an artery that supplies the anterior chest wall and the breasts. It is a paired artery, with one running along each side of the sternum, to continue after its bifurc ...

Development

The

aortic sac The aortic sac or aortic bulb is a dilated structure in mammalian embryos, lined by endothelial cells and is the most distal part of the truncus arteriosus. It is the primordial vascular channel from which the aortic arches arise (and eventually t ...

is the embryological precursor of the proximal portion of the aortic arch. It is chronologically the first portion of the aorta to form, and appears as a dilation superior to the

truncus arteriosus The truncus arteriosus is a structure that is present during embryonic development. It is an arterial trunk that originates from both ventricles of the heart that later divides into the aorta and the pulmonary trunk. Structure The truncus arteri ...

. Between the two horns of aortic sac, right horn gives rise to the brachiocephalic artery. Then the right horn fuses with the right-sided third and fourth

aortic arches The aortic arches or pharyngeal arch arteries (previously referred to as branchial arches in human embryos) are a series of six paired embryological vascular structures which give rise to the great arteries of the neck and head. They are ventral ...

, which give rise to the right common carotid artery and the proximal right subclavian artery respectively. Eventually, brachiocephalic artery is derived from

ventral aorta The aorta ( ; : aortas or aortae) is the main and largest artery in the human body, originating from the left ventricle of the heart, branching upwards immediately after, and extending down to the abdomen, where it splits at the aortic bifurcat ...

, same as

ascending aorta The ascending aorta (AAo) is a portion of the aorta commencing at the upper part of the base of the left ventricle, on a level with the lower border of the third costal cartilage behind the left half of the sternum. Structure It passes obliqu ...

. Left horn forms proximal ascending portion of aorta.

Function

The brachiocephalic artery sends blood from the heart to the right arm, head, and neck. Oxygenated blood from the aortic trunk is taken through the brachiocephalic artery into the right subclavian artery, which transports blood to the right arm, and into the right common carotid artery, where blood is transported to the head and neck.

Clinical significance

Innominate artery aneurysms represent 3% of all arterial

aneurysm An aneurysm is an outward :wikt:bulge, bulging, likened to a bubble or balloon, caused by a localized, abnormal, weak spot on a blood vessel wall. Aneurysms may be a result of a hereditary condition or an acquired disease. Aneurysms can also b ...

s. Because there is a risk of thromboembolic complications and spontaneous rupture, surgical repair is usually recommended early on after discovery. Innominate artery aneurysms often present with signs of innominate artery compression syndrome and have a very high risk of rupture. The majority of IA aneurysms are due to

atherosclerosis Atherosclerosis is a pattern of the disease arteriosclerosis, characterized by development of abnormalities called lesions in walls of arteries. This is a chronic inflammatory disease involving many different cell types and is driven by eleva ...

. Other causes include

syphilis Syphilis () is a sexually transmitted infection caused by the bacterium ''Treponema pallidum'' subspecies ''pallidum''. The signs and symptoms depend on the stage it presents: primary, secondary, latent syphilis, latent or tertiary. The prim ...

tuberculosis Tuberculosis (TB), also known colloquially as the "white death", or historically as consumption, is a contagious disease usually caused by ''Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can al ...

, Kawasaki's disease,

Takayasu's arteritis Takayasu's arteritis (TA), also known as aortic arch syndrome, nonspecific aortoarteritis, and pulseless disease, is a form of large vessel granulomatous vasculitisAmerican College of Physicians (ACP). Medical Knowledge Self-Assessment Program (M ...

Behçet's disease Behçet's disease (BD) is a type of inflammatory disorder which affects multiple parts of the body. The most common symptoms include painful sores on the mucous membranes of the mouth and other parts of the body, inflammation of parts of the ...

connective tissue disease Connective tissue diseases (also termed connective tissue disorders, or collagen vascular diseases), are medical conditions that affect connective tissue. Connective tissues protect, support, and provide structure for the body's other tissues a ...

, and

angiosarcoma Angiosarcoma is a rare and aggressive cancer that starts in the endothelial cells that line the walls of blood vessels or lymphatic vessels. Since they are made from Endothelium, vascular lining, they can appear anywhere and at any age, but older ...

. Tracheoinnominate fistula (TIF) is a surgical emergency with high mortality rates. Reported incidence is 0.1%-1.0% after

tracheostomy Tracheotomy (, ), or tracheostomy, is a surgical airway management procedure which consists of making an incision on the front of the neck to open a direct airway to the trachea. The resulting stoma (hole) can serve independently as an airway ...

. TIF is usually fatal once it bleeds. For the successful management of TIF, treatment should be initiated immediately with special considerations kept in mind. Several abnormalities of the brachiocephalic artery have been reported. A retroesophageal innominate artery is a rare congenital anomaly. Also, aberrant innominate artery crossing anterior to the trachea just below the thyroid isthmus was reported. Anterior neck surgeries such as bronchoscopies and mediastinoscopies are common and safe procedure, since operating around the trachea, no major vessel is encountered in the surgical field. However, when this type of abnormality is encountered, even minor trauma can lead to mass bleeding culminating in death. Aberrant innominate artery can cause incomplete

vascular ring A vascular ring is a congenital defect in which there is an abnormal formation of the aorta and/or its surrounding blood vessels. The trachea and esophagus are completely encircled and sometimes compressed by a "ring" formed by these vessels, whic ...

. It does not completely encircle the

and

esophagus The esophagus (American English), oesophagus (British English), or œsophagus (Œ, archaic spelling) (American and British English spelling differences#ae and oe, see spelling difference) all ; : ((o)e)(œ)sophagi or ((o)e)(œ)sophaguses), c ...

, but some compress either the trachea or esophagus. Anomalous innominate artery originates later from the transverse arch and then crosses the trachea causing anterior tracheal compression.

Additional images

File:Slide15e.JPG, Brachiocephalic artery File:Slide3eeee.JPG, Brachiocephalic trunk

References

External links

* {{Authority control Arteries of the thorax