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StatPearls . Endowment Island (FL): StatPearls Publishing; 2021 Jan-.



The aorta is the biggest vessel within the human being body. The originates indigenous the left ventricle that the love anterior come the pulmonary artery before arching posteriorly and descending along the posterior mediastinum. It descends come the level that the L4 vertebral body where it bifurcates right into the left and also right typical iliac arteries. The is the key artery in the body and distributes oxygenated blood come the entire systemic circulation. This ar will be minimal to the thoracic part of the aorta, which contains the ascending aorta, aortic arch, and also descending thoracic aorta before it the cross the level that the diaphragm where it i do not care the ab aorta. The thoracic aorta is responsible for providing oxygenated blood come multiple structures, including the head, neck, top extremities, and thoracic structures.

Structure and also Function

The thoracic aorta originates from the left ventricle, guarded by the aortic valve. Just above the cusp of the aortic valve, the aorta gives off the left and also right key coronary arteries that operation along coronary grooves of the heart and also are responsible because that perfusion that the myocardium. The initial portion of the aorta ascending behind the sternum is described as the ascending aorta, extends approximately to the level of the T4 vertebral body. From this point, the is well-known as the aortic arch and begins to arch posteriorly and to the left of the vertebral bodies in the posterior mediastinum. The aortic arch both begins and also ends in ~ the level of the 2nd rib; it lies within the superior mediastinum. In the chest radiographs, the aortic arch is identifiable together "the aortic knob." The aortic arch provides off three branches including:

Brachiocephalic artery (also recognized as the innominate artery) is the very first arch vessel to branch off - it travels superiorly and also to the ideal side the the body and also bifurcates into the best subclavian artery and right common carotid artery
The left usual carotid artery is the subsequent vessel come branch indigenous the aortic arch
Left subclavian artery is the 3rd arch vessel come branch indigenous the aortic arch

The final section the the aortic arch is just distal come the origin of the left subclavian artery and is recognized as the aortic isthmus. Over there is a gentle narrowing the the aorta the occurs in ~ the site of the ligamentum arteriosum, i beg your pardon is a remnant that the ductus arteriosus.  native the fourth thoracic vertebra, it continues as the diminish aorta to travel downward to the diaphragmatic hiatus in ~ the level the T12 wherein it exits the thorax. The diminish aorta provides off many vessels prior to exiting the thoracic cavity, consisting of arteries to it is provided the pericardium, bronchi, mediastinum, and esophagus; it additionally gives off the premium phrenic arteries, posterior intercostal arteries, and subcostal arteries.


The aorta establishes during the third gestational week.<1> The ascending aorta and also aortic arch build independently from two various embryologic tracts. The ascending aorta develops from the truncus arteriosus which is a ingredient of love development. The truncus arteriosus is a single outflow tract the forms throughout heart development. It originates from both the left and right ventricle the the heart. The truncus arteriosus is then separated by the aorticopulmonary septum to provide rise come two separate outflow tracts, later recognized as the pulmonary artery and also ascending aorta. 

The aortic arch forms through the breakthrough of the branchial arch arteries. Over there are six branchial arch arteries, likewise known as the pharyngeal arch vessels. These build into the following<2><3>:

The very first branchial arch artery creates the maxillary and external carotid arteries
The second branchial arch artery leads to the development of the stapedial arteries
The third branchial arch artery contributes come the formation of the right typical carotid arteries and proximal interior carotid artery
The fourth branchial arch artery develops the main section of the aortic arch, and the proximal best subclavian artery - the left subclavian artery occurs from the left seventh intersegmental artery, which explains a set of arteries that construct from the dorsal aorta
The 5th branchial arch walk not kind vessels and regresses
The 6th branchial arch leads to the development of the key pulmonary artery, left and right pulmonary artery, and ductus arteriosus

Surgical Considerations

Coarctation the the aorta

Coarctation that the aorta refers to a congenital problem in i beg your pardon the aorta narrows, obstructing distal blood flow; this most generally occurs in proximity come the ductus arteriosus through classifications the preductal coarctation, ductal coarctation, and also postductal coarctation.

Preductal coarctation occurs proximal come the ductus arteriosus; this most frequently occurs as a result of a congenital heart anomaly the leader to lessened blood flow to the left next of the heart and also aorta, bring about hypoplastic development.

Ductal coarctation occurs at the insertion the the ductus arteriosus and most often appears at birth together the ductus arteriosus obliterates.

Postductal coarctation wake up distal come the ductus arteriosus, i beg your pardon is the many common form in adults. It frequently presents as hypertension in the top extremities and also weak pulses in the reduced extremities. This presentation is because of increased blood flow through the aortic arch vessels and also decreased blood circulation to the to decrease aorta distal to the stenotic segment. Collateral vessels may rise in size to help in the delivery of blood come the diminish aorta. This collateralization most often occurs with the subclavian artery right into the inner thoracic artery which goes come the anterior intercostal artery, come the posterior intercostal artery, and finally into the to decrease thoracic aorta. The dilation that the intercostal arteries may result in the characteristic detect of rib notching top top chest x-ray.<4><5>

Coarctation that the aorta outcomes in far-ranging morbidity in patient with severe narrowing and also poor outcome in patients who survive beyond one year that age.<6> Treatment choices include operation repair, balloon angioplasty, and also endovascular stent placement. Return these alternatives are available, the decision on one optimal therapy strategy can be complicated. There is no a typical of care practice or algorithm in treating these patients.<7> management is in ~ the physician"s discretion with age at presentation and complexity that coarctation affecting treatment choice. 

Clinical Significance

Aortic aneurysm

A thoracic aortic aneurysm refers to a dilatation the the proximal ascending aorta; this is most frequently the an outcome of chronic hypertension as soon as seen in adults. In young adults, the most typical underlying factor is a connective organization disorder such together Marfan syndrome or Ehler-Danlos syndrome. One aortic aneurysm is the concern because dilation of the aorta outcomes in weakening of the aortic wall, raising risk that aortic rupture or dissection. Because that this reason, elective repair is often the recommendation once an aneurysm has reached a diameter that 5.5cm or greater.<8><9> Elective repair can reduce the danger of rupture and also survival to close to normal.

Aortic dissection

Aortic dissection describes the disruption the the innermost great of the aorta, enabling blood come tunnel through the main portion that the aortic wall. It most regularly occurs at the proximal section of the ascending aorta, simply distal to the aortic valve. Aortic dissections can then propagate distally or proximally through the aortic wall. Aortic dissections room a life-threatening emergency that calls for surgical repair to increase the opportunities of survival. Practically 40% of patients with acute aortic dissections expire immediately. Of those who survive the early event, about 80% will die within two weeks.<10>

Patent ductus arteriosus

The ductus arteriosus is a communication between the pulmonary artery and also the aortic arch in fetal life. It usually closes through the 2nd day after birth in full-term babies. If this communication persists beyond two days, that is called patent ductus arteriosus. Depending on the size of patency this problem can lead to failure to thrive and also heart failure.

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Other aberrant conditions of development seen in the aorta space hypoplastic ascending aorta, interrupted aortic arch, ideal aortic arch, and double aortic arch.<1>