Subclavian Artery Definition
The right and left subclavian arteries are significant arteries that carry blood to the head, neck, chest, shoulders, and upper extremities. The term “subclavian” refers to the location of these veins, which is “under the collarbone.” Peripheral arterial disease and other clinical diseases are occasionally linked to the subclavian arteries.
Anatomy of the Subclavian Arteries
Origin of the Subclavian Arteries
The subclavian arteries are located just below the clavicles in the thorax (collar bones). Each artery begins at a distinct location. The aortic arch gives birth to the left subclavian artery. The right subclavian artery, on the other hand, starts from the brachiocephalic artery (also called the brachiocephalic trunk).
Paths of the Left and Right Subclavian Arteries
Each subclavian artery travels to the anterior scalene muscle, which is part of the group of scalene muscles on each side of the neck, from its respective point of origin. After that, each artery passes between the anterior and medial scalene muscles. The arteries enter the axillary area, which is basically the armpit, at this point. It becomes the axillary artery as it reaches the lateral border of the first rib.
The first, second, and third segments of each subclavian artery may be separated into three divisions. The first section runs from the point of origin to the anterior scalene muscle’s medial border. Behind the anterior scalene muscle lies the second section. Between the lateral border of the anterior scalene muscle and the outside portion of the first rib, lies the third and last section (before the subclavian artery becomes the axillary artery).
Each subclavian artery branches out into multiple significant arteries before entering the axillary artery. The following are some of the more important branches:
- The subclavian arteries give rise to the vertebral arteries, which are some primary arteries in the neck. These veins, together with the internal carotid arteries, give blood to the brain and spinal cord. The vertebral arteries supply about 20% of the blood flow to the brain.
- Between the beginnings of the subclavian arteries and the anterior scalene muscles, the thyrocervical trunk emerges (the first portion of the vessel). The thyroid, upper back, shoulder, and neck muscles all get blood from the thyrocervical trunk.
- The costocervical trunk is a branch of the subclavian artery that provides blood to the neck muscles.
- The internal thoracic artery (also known as the mammary artery) develops near the subclavian artery’s origin. The thymus, the pericardium of the heart, the chest wall, and the breasts all get blood from this vein.
- The dorsal scapular artery serves the levator scapulae, rhomboids, and trapezius muscles in the back and neck.
Subclavian Arteries Function
The head, neck, and upper extremities are all supplied with oxygenated blood through the subclavian arteries.
Subclavian Arteries Clinical Relevance
Trauma
The clavicles, surrounding muscles, and connective tissue protect the subclavian arteries, making injury to them uncommon. In fewer than 5% of trauma cases, the subclavian arteries are injured. If they are injured, the trauma is generally caused by a penetrating wound, such as a gunshot wound or a knife wound.
Aberrant Subclavian Artery
An anatomical variety of the subclavian artery is known as an aberrant subclavian artery. It’s a very uncommon congenital disorder that affects fewer than 1% of the population. It does, however, commonly co-occur with other cardiac anomalies, such as those seen in Down syndrome patients.
Fortunately, this condition seldom causes any symptoms. However, symptoms may develop over time, and it can lead to issues with swallowing and chest discomfort later in life. Q278 is the ICD-10 code for an abnormal subclavian artery.
Subclavian Artery Aneurysm
The subclavian artery may expand due to a weakness, which is known as an aneurysm. Trauma, thoracic outlet blockage (compression of the blood arteries surrounding the upper thorax), and arteriosclerosis are all common causes of an aneurism. The accumulation of fatty plaque in the arteries is referred to as atherosclerosis. Hypertension, obesity, diabetes, and smoking are all risk factors for the development of atherosclerosis.
Aneurysms in the subclavian artery may cause chest discomfort, numbness, difficulty swallowing, and weariness in the upper extremities. Surgery is the most prevalent method of repair.
Subclavian Artery Stenosis
Peripheral artery disease includes subclavian artery stenosis. This condition is caused by arterial narrowing and is most often caused by atherosclerosis. Because the illness advances slowly, there are typically no signs. As a consequence of the constriction, the body adjusts by creating new vessels to circumvent the blood flow. It may, however, produce arm weakness and weariness, as well as dizziness and light-headedness.
Subclavian Artery Thrombosis
Subclavian artery thrombosis develops when blood flow in the subclavian artery is blocked by a blockage. It is usually the consequence of previous vascular injury, such as trauma or atherosclerosis. Congenital abnormalities and certain autoimmune illnesses, on the other hand, may cause it.
Reference
- Casserly, I.P., & Kapadia, S.R., Anatomy. In: Bhatt DL, editor. Guide to Peripheral and Cerebrovascular Intervention. London: Remedica; 2004. Available from: https://www.ncbi.nlm.nih.gov/books/NBK27410
- Rahimi, O., & Geiger, Z. (2019). Anatomy, Thorax, Subclavian Arteries. In StatPearls. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/30969558
- Yang, C., Shu, C., Li, M., Li, Q., & Kopp, R. (2012). Aberrant subclavian artery pathologies and Kommerell’s diverticulum: A review and analysis of published endovascular/hybrid treatment options. Journal of Endovascular Therapy, Vol. 19, pp. 373–382. https://doi.org/10.1583/11-3673MR.1.
