The brachiocephalic artery (or brachiocephalic trunk or innominate artery) is an

artery An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body (tissues, lungs, brain etc.). Most arteries carry oxygenated blood; the two exceptions are the pul ...

of the

mediastinum The mediastinum (from ) is the central compartment of the thoracic cavity. Surrounded by loose connective tissue, it is an undelineated region that contains a group of structures within the thorax, namely the heart and its vessels, the esophagu ...

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 th ...

and the

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 animals may ...

and

neck The neck is the part of the body on many vertebrates that connects the head with the torso. The neck supports the weight of the head and protects the nerves that carry sensory and motor information from the brain down to the rest of the body. In ...

. 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 a ...

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

common carotid artery In anatomy, the left and right common carotid arteries (carotids) (Entry "carotid"
in
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 supplie ...

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

brachiocephalic vein The left and right brachiocephalic veins (previously called innominate veins) are major veins in the upper chest, formed by the union of each corresponding internal jugular vein and subclavian vein. This is at the level of the sternoclavicular j ...

Structure

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

costal cartilage The costal cartilages 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, providing medial extension. ...

, 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 t ...

. 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

common carotid artery In anatomy, the left and right common carotid arteries (carotids) (Entry "carotid"
in
subclavian arteries 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 supplie ...

. The artery then crosses the

trachea The trachea, also known as the windpipe, is a Cartilage, cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all air-breathing animals with lungs. The trachea extends ...

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

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 vein th ...

, right brachiocephalic vein, and

pleura The pulmonary pleurae (''sing.'' pleura) are the two opposing layers of serous membrane overlying the lungs and the inside of the surrounding chest walls. The inner pleura, called the visceral pleura, covers the surface of each lung and dips b ...

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

Thymus The thymus is a specialized primary lymphoid organ of the immune system. Within the thymus, thymus cell lymphocytes or ''T cells'' mature. T cells are critical to the adaptive immune system, where the body adapts to specific foreign invaders. ...

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

manubrium The sternum 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 blood vessels from injury. Sha ...

sternum The sternum 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 blood vessels from injury. Sh ...

Branches

The

thyroid ima artery The thyroid ima artery (thyroidea ima artery, ''arteria thyroidea ima'', thyroid artery of Neubauer or the lowest thyroid artery) is an artery of the head and neck. It is an anatomical variant that, when present, supplies blood to the thyroid gl ...

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 in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thy ...

, 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 ( ) is the main and largest artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta distributes ...

, the

right common carotid In anatomy, the left and right common carotid arteries (carotids) (Entry "carotid"
in
subclavian or the

internal mammary In human anatomy, the internal thoracic artery (ITA), previously commonly known as the internal mammary artery (a name still common among surgeons), is an artery that supplies the anterior chest wall and the breasts. It is a paired artery, with ...

Development

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 th ...

is the embryological precursor of 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 arterio ...

. 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 ( ) is the main and largest artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta distributes ...

, same as ascending aorta. Left horn forms proximal ascending portion of aorta.

Function

Brachiocephalic artery brings blood from heart to right arm, head, and neck.

Clinical significance

Innominate artery aneurysms represents 3% of all arterial

aneurysms An aneurysm is an outward 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 be a nidus (s ...

. Since there is the risk of thromboembolic complications and spontaneous rupture, surgical repair is usually recommended on an early period. Innominate artery aneurysms can 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 in which the wall of the artery develops abnormalities, called lesions. These lesions may lead to narrowing due to the buildup of atheroma, atheromatous plaque. At onset there are usu ...

. Other causes include

syphilis Syphilis () is a sexually transmitted infection caused by the bacterium ''Treponema pallidum'' subspecies ''pallidum''. The signs and symptoms of syphilis vary depending in which of the four stages it presents (primary, secondary, latent, an ...

tuberculosis Tuberculosis (TB) is an infectious disease usually caused by '' Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in ...

, 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 (MK ...

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 e ...

connective tissue disease A connective tissue disease (collagenosis) is any disease that has the connective tissues of the body as a target of pathology. Connective tissue is any type of biological tissue with an extensive extracellular matrix that supports, binds togeth ...

, 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 vascular lining, they can appear anywhere and at any age, but older people are ...

. Tracheo-innominate artery 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 (cut) on the anterior aspect (front) of the neck and opening a direct airway through an incision in the Vertebrate trachea, trache ...

. TIF is usually fatal once it bleeds. For the successful management of TIF, treatment should be initiated immediately with the special considerations kept in mind. Several abnormalities of 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) or oesophagus (British English; both ), non-technically known also as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the ...

, 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