The abdominal aorta (from the Greek aortê, meaning large artery) corresponds to part of the aorta, the largest artery in the body.

Position. Located between the thoracic vertebra T12 and the lumbar vertebra L4, the abdominal aorta constitutes the last part of the aorta. (1) It follows the descending aorta, the last part of the thoracic aorta. The abdominal aorta ends by dividing into two lateral branches which make up the left and right common iliac arteries, as well as a third middle branch, the median sacral artery.

Peripheral branches. The abdominal aorta gives rise to several branches, notably parietal and visceral (2):

• Lower phrenic arteries which are intended for the underside of the diaphragm
• Celiac trunk that divides into three branches, the common hepatic artery, the splenic artery, and the left gastric artery. These branches are intended to vascularize the liver, stomach, spleen, and part of the pancreas
• Superior mesenteric artery which is used for blood supply to the small and large intestine
• Adrenal arteries that serve the adrenal glands
• Renal arteries which are intended to supply the kidneys
• Ovarian and testicular arteries which respectively serve the ovaries as well as part of the uterine tubes, and the testes
• Inferior mesenteric artery that serves part of the large intestine
• Lumbar arteries which are intended for the posterior part of the abdominal wall
• Median sacral artery that supplies the coccyx and the sacrum
• Common iliac arteries which are intended to supply the organs of the pelvis, the lower part of the abdominal wall, as well as the lower limbs

Irrigation. The abdominal aorta plays a major role in the vascularization of the body thanks to its different branches supplying the abdominal wall and visceral organs.

Wall elasticity. The aorta has an elastic wall that allows it to adapt to the pressure differences that arise during periods of cardiac contraction and rest.

The abdominal aortic aneurysm is its dilation, occurring when the walls of the aorta are no longer parallel. These aneurysms are usually spindle-shaped, i.e. affecting a major part of the aorta, but can also be sacciform, being localized only to a portion of the aorta (3). The cause of this pathology can be linked to an alteration of the wall, to atherosclerosis and can sometimes be of infectious origin. In some cases, abdominal aortic aneurysm can be difficult to diagnose with the absence of specific symptoms. This is particularly the case with a small aneurysm, characterized by a diameter of the abdominal aorta less than 4 cm. Nevertheless, some abdominal or lower back pain may be felt. As it progresses, an abdominal aortic aneurysm can lead to:

• Compression of neighboring organs such as part of the small intestine, the ureter, the inferior vena cava, or even certain nerves;
• Thrombosis, that is to say the formation of a clot, at the level of the aneurysm;
• Acute arterial obliteration of the lower limbs corresponding to the presence of an obstacle preventing the blood from circulating normally;
• an infection ;
• a ruptured aneurysm corresponding to the rupture of the wall of the aorta. The risk of such a rupture becomes significant when the diameter of the abdominal aorta exceeds 5 cm.
• a fissure crisis corresponding to a “pre-rupture” and resulting in pain;

Surgical treatment. Depending on the stage of the aneurysm and the patient’s condition, surgery may be performed on the abdominal aorta.

Medical supervision. In case of minor aneurysms, the patient is placed under medical supervision but does not necessarily require surgery.

Physical examination. First, a clinical examination is performed to assess the abdominal and / or lumbar pain felt.

Medical imaging examination To confirm a diagnosis, an abdominal ultrasound may be performed. It can be supplemented by a CT scan, MRI, angiography, or even an aortography.

Since 2010, numerous screenings have been carried out to prevent aneurysms of the abdominal aorta.