Aorta
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- AORTA can also mean "always-on real-time access", referring to WAN computer networks.
The largest artery in the human body, the aorta originates from the left ventricle of the heart and brings oxygenated blood to all parts of the body in the systemic circulation.
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The course of the aorta
The aorta is usually divided into several segments. The portion above the diaphragm (in the thorax) is called the thoracic aorta and is sometimes further subdivided into the ascending aorta, aortic arch and descending (thoracic) aorta. The portion below the diaphragm (in the abdomen) is known as the abdominal aorta.
Thoracic aorta
Image:Thoracic aorta.jpg The initial part of the aorta, the ascending aorta, rises out of the left ventricle, from which it is separated by the aortic valve. The two coronary arteries of the heart arise from the aortic root, just above the cusps of the aortic valve.
The aorta then arches back over the right pulmonary artery. Three vessels come out of the aortic arch, the
- brachiocephalic artery,
- left common carotid artery, and
- left subclavian artery.
These vessels supply blood to the head, neck, thorax and upper limbs.
The aorta gives off several paired branches as it descends in the thorax. These includes the
Abdominal aorta
Image:Abdominal aorta.gif The abdominal aorta travels down the posterior wall of the abdomen, the abdominal aorta runs on the left of the inferior vena cava, giving off major blood vessels to the gut organs and kidneys. There are many recognized variants in the vasculature of the gastrointestinal system. The most common arrangement is for the abdminal aorta is to give off (in order) a
The renal arteries usually branch from the abdominal aorta in between the celiac artery and the superior mesenteric artery.
The aorta terminates by dividing into two branches, the left and right common iliac arteries that branch to supply blood to the lower limbs and the pelvis.
Features
The aorta is an elastic artery, and as such is quite distensible. When the left ventricle contracts to force blood into the aorta, the aorta expands. This stretching gives the potential energy that will help maintain blood pressure during diastole, as during this time the aorta contracts passively.
Diseases
- Aneurysm of sinus of Valsalva
- Aortic aneurysm
- Aortic coarctation
- Marfan syndrome
- inborn cardiovascular defects
External links
| Cardiovascular system | edit |
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Heart - Aorta - Arteries - Arterioles - Capillaries - Venules - Veins - Venae cavae - Pulmonary arteries - Lungs - Pulmonary veins - Blood |
