Abdominal aorta

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Abdominal aorta
Gray531.png
The abdominal aorta and its branches.
Details
Latin Aorta abdominalis,
pars abdominalis aortae
Source
Thoracic aorta
Branches
Celiac artery, superior mesenteric artery, inferior mesenteric artery, common iliac 6 others
Inferior vena cava
Identifiers
Gray's p.602
MeSH A07.231.114.056.205
Dorlands
/Elsevier
p_07/12616144
TA A12.2.12.001
FMA FMA:3789
Anatomical terminology

The abdominal aorta is the largest artery in the abdominal cavity. As part of the aorta, it is a direct continuation of the descending aorta (of the thorax).

Structure[edit]

The abdominal aorta begins at the level of the diaphragm, crossing it via the aortic hiatus, technically behind the diaphragm, at the vertebral level of T12. It travels down the posterior wall of the abdomen, anterior to the vertebral column. It thus follows the curvature of the lumbar vertebrae, that is, convex anteriorly. The peak of this convexity is at the level of the third lumbar vertebra (L3). It runs parallel to the inferior vena cava, which is located just to the right of the abdominal aorta, and becomes smaller in diameter as it gives off branches. This is thought to be due to the large size of its principal branches. At the 11th rib, the diameter is 122mm long and 55mm wide and this is because of the constant pressure

Branches[edit]

The abdominal aorta supplies blood to much of the abdominal cavity. It begins at T12, and usually has the following branches:

Artery Branch Vertebra Type Paired? A/P Description
inferior phrenic T12 Parietal yes post. originates just below the diaphragm, supplying it from below
celiac Upper L1 Visceral no ant. large anterior branch
superior mesenteric Lower L1 Visceral no ant. large anterior branch, arises just below celiac trunk
middle suprarenal L1 Visceral yes post. to adrenal gland
renal In between L1 and L2 Visceral yes post. large artery, each arising from the side of the aorta; supplies corresponding kidney; arises in the transpyloric plane
gonadal L2 Visceral yes ant. ovarian artery in females; testicular artery in males
lumbar L1-L4 Parietal yes post. four on each side that supply the abdominal wall and spinal cord
inferior mesenteric L3 Visceral no ant. large anterior branch
median sacral L4 Parietal no post. artery arising from the middle of the aorta at its lowest part
common iliac L4 Terminal yes post. branches (bifurcates) to supply blood to the lower limbs and the pelvis, ending the abdominal aorta

Note that the bifurcation (union) of the inferior vena cava is at L5 and therefore below that of the bifurcation of the aorta.

Contrast enhanced MRA of the abdominal aorta demonstrating normal paired arteries.
  1. inferior phrenic a.
  2. celiac a.
    1. left gastric a.
    2. splenic a.
      1. short gastric arteries (6)
      2. splenic arteries (6)
      3. left gastroepiploic a.
    3. common hepatic a.
      1. cystic a.
      2. right gastric a.
      3. gastroduodenal a.
        1. right gastroepiploic a.
        2. superior pancreaticoduodenal a.
      4. right hepatic a.
      5. left hepatic a.
  3. superior mesenteric a.
    1. jejunal and ileal arteries
    2. inferior pancreaticoduodenal a.
    3. middle colic a.
    4. right colic a.
    5. ileocolic a
      1. anterior cecal a.
      2. posterior cecal a. – appendicular a.
      3. ileal a.
      4. colic a.
  4. middle suprarenal a.
  5. renal a.
  6. testicular or ovarian a.
  7. four lumbar arteries
  8. inferior mesenteric a.
    1. left colic a.
    2. sigmoid arteries (2 or 3)
    3. superior rectal a.
  9. median sacral a.
  10. common iliac a.
    1. external iliac a.
    2. internal iliac a.

Relations[edit]

The abdominal aorta lies slightly to the left of the midline of the body. It is covered, anteriorly, by the lesser omentum and stomach, behind which are the branches of the celiac artery and the celiac plexus; below these, by the lienal vein(splenic vein), the pancreas, the left renal vein, the inferior part of the duodenum, the mesentery, and aortic plexus.

Posteriorly, it is separated from the lumbar vertebræ and intervertebral fibrocartilages by the anterior longitudinal ligament and left lumbar veins.

On the right side it is in relation above with the azygos vein, cisterna chyli, thoracic duct, and the right crus of the diaphragm—the last separating it from the upper part of the inferior vena cava, and from the right celiac ganglion; the inferior vena cava is in contact with the aorta below.

On the left side are the left crus of the diaphragm, the left celiac ganglion, the ascending part of the duodenum, and some coils of the small intestine.

Relationship with inferior vena cava[edit]

The abdominal aorta's venous counterpart, the inferior vena cava (IVC), travels parallel to it on its right side.

  • Above the level of the umbilicus, the aorta is somewhat posterior to the IVC, sending the right renal artery travelling behind it. The IVC likewise sends its opposite side counterpart, the left renal vein, crossing in front of the aorta.
  • Below the level of the umbilicus, the situation is generally reversed, with the aorta sending its right common iliac artery to cross its opposite side counterpart (the left common iliac vein) anteriorly.tatenda

Collateral circulation[edit]

The collateral circulation would be carried on by the anastomoses between the internal thoracic artery and the inferior epigastric artery; by the free communication between the superior and inferior mesenterics, if the ligature were placed between these vessels; or by the anastomosis between the inferior mesenteric artery and the internal pudendal artery, when (as is more common) the point of ligature is below the origin of the inferior mesenteric artery; and possibly by the anastomoses of the lumbar arteries with the branches of the internal iliac artery.

Development[edit]

Clinical relevance[edit]

Aneurysm[edit]

History[edit]

Additional images[edit]

See also[edit]

This article uses anatomical terminology; for an overview, see anatomical terminology.

External links[edit]