Abdominal aorta
Encyclopedia
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).
, 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 about 25 mm; above the origin of the renal arteries, 22 mm; below the renals, 20 mm; and at the bifurcation, 19 mm.
Note that the bifurcation (union) of the inferior vena cava
is at L5 and therefore below that of the bifurcation of the aorta.
and stomach
, behind which are the branches of the celiac artery and the celiac plexus; below these, by the lienal vein(splenic artery), 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
.
(IVC), travels parallel to it on its right side.
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
.
Abdominal cavity
The abdominal cavity is the body cavity of the human body that holds the bulk of the viscera. It is located below the thoracic cavity, and above the pelvic cavity. Its dome-shaped roof is the thoracic diaphragm , and its oblique floor is the pelvic inlet...
. As part of the aorta
Aorta
The aorta is the largest artery in the body, originating from the left ventricle of the heart and extending down to the abdomen, where it branches off into two smaller arteries...
, it is a direct continuation of the descending aorta
Descending aorta
The descending aorta is part of the aorta, the largest artery in the body. The descending aorta is the part of the aorta beginning at the aortic arch that runs down through the chest and abdomen. The descending aorta is divided into two portions, the thoracic and abdominal, in correspondence with...
(of the thorax).
Path
It begins at the level of the diaphragm, crossing it via the aortic hiatusAortic hiatus
The aortic hiatus is a hole in the human diaphragm. It is the lowest and most posterior of the large apertures.It is located approximately at the level of the twelfth thoracic vertebra .-Structure:...
, 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
Inferior vena cava
The inferior vena cava , also known as the posterior vena cava, is the large vein that carries de-oxygenated blood from the lower half of the body into the right atrium of the heart....
, 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 about 25 mm; above the origin of the renal arteries, 22 mm; below the renals, 20 mm; and at the bifurcation, 19 mm.
Branches
The abdominal aorta supplies blood to much of the abdominal cavity. It begins at T12, and usually has the following branches:| Branch | Vertebra | Type | Paired? | A/P | Description >- | inferior phrenic |
T12 | Parietal | yes | post. | >- | Upper L1 | Visceral | no | ant. | >- | Lower L1 | Visceral | no | ant. | >- | L1 | Visceral | yes | post. | adrenal gland Adrenal gland In mammals, the adrenal glands are endocrine glands that sit atop the kidneys; in humans, the right suprarenal gland is triangular shaped, while the left suprarenal gland is semilunar shaped... >- | renal Renal artery The renal arteries normally arise off the side of the abdominal aorta, immediately below the superior mesenteric artery, and supply the kidneys with blood. Each is directed across the crus of the diaphragm, so as to form nearly a right angle with the aorta.... |
In between L1 and L2 | Visceral | yes | post. | transpyloric plane Transpyloric plane An upper transverse line also known as Addison's Plane, is located halfway between the jugular notch and the upper border of the pubic symphysis; this indicates the margin of the transpyloric plane, which in most cases cuts through the pylorus, the tips of the ninth costal cartilages and the lower... >- | gonadal Gonadal artery The term gonadal artery is a generic term for a paired artery, with one arising from the abdominal aorta for each gonad. Specifically, it can refer to:* the testicular artery in males* the ovarian artery in females... |
L2 | Visceral | yes | ant. | ovarian artery Ovarian artery In human anatomy, the ovarian artery is a blood vessel that supplies oxygenated blood to the ovary. It arises from the abdominal aorta below the renal artery, and does not pass out of the abdominal cavity. It can be found in the suspensory ligament of the ovary, anterior to the ovarian vein and... in females; testicular artery Testicular artery The testicular artery is a branch of the abdominal aorta that supplies blood to the testis. It is a paired artery, with one for each of the testes.... in males >- | lumbar Lumbar arteries The lumbar arteries are in parallel with the intercostals.They are usually four in number on either side, and arise from the back of the aorta, opposite the bodies of the upper four lumbar vertebræ.... |
L1-L4 | Parietal | yes | post. | spinal cord Spinal cord The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the brain . The brain and spinal cord together make up the central nervous system... >- | inferior mesenteric Inferior mesenteric artery In human anatomy, the inferior mesenteric artery, often abbreviated as IMA, supplies the large intestine from the left colic flexure to the upper part of the rectum, which includes the descending colon, the sigmoid colon, and part of the rectum... |
L3 | Visceral | no | ant. | >- | L4 | Parietal | no | post. | >- | L4 | Terminal | yes | post. | branches (bifurcates) to supply blood to the lower limb Lower limb The lower limb is a limb of the body.According to Terminologia Anatomica, it includes the pelvic girdle, buttocks, hip, and thigh, as well as the components distal to the knee.-References:... s and the pelvis, ending the abdominal aorta |
Note that the bifurcation (union) of the inferior vena cava
Inferior vena cava
The inferior vena cava , also known as the posterior vena cava, is the large vein that carries de-oxygenated blood from the lower half of the body into the right atrium of the heart....
is at L5 and therefore below that of the bifurcation of the aorta.
- inferior phrenic a.
- celiac a.
- left gastric a.
- splenic a.
- short gastric arteries (6)
- splenic arteries (6)
- left gastroepiploic a.
- hepatic a.
- cystic a.
- right gastric a.
- gastroduodenal a.
- right gastroepiploic a.
- superior pancreaticoduodenal a.
- right hepatic a.
- left hepatic a.
- superior mesenteric a.
- jejunal and ileal arteries
- inferior pancreaticoduodenal a.
- middle colic a.
- right colic a.
- ileocolic a
- anterior cecal a.
- posterior cecal a. – appendicular a.
- ileal a.
- colic a.
- middle suprarenal a.
- renal a.
- testicular or ovarian a.
- four lumbar arteries
- inferior mesenteric a.
- left colic a.
- sigmoid arteries (2 or 3)
- superior rectal a.
- median sacral a.
- common iliac a.
- external iliac a.
- internal iliac a.
Relations
The abdominal aorta lies slightly to the left of the midline of the body. It is covered, anteriorly, by the lesser omentumLesser omentum
The lesser omentum is the double layer of peritoneum that extends from the liver to the lesser curvature of the stomach and the start of the duodenum.- Structure :...
and stomach
Stomach
The stomach is a muscular, hollow, dilated part of the alimentary canal which functions as an important organ of the digestive tract in some animals, including vertebrates, echinoderms, insects , and molluscs. It is involved in the second phase of digestion, following mastication .The stomach is...
, behind which are the branches of the celiac artery and the celiac plexus; below these, by the lienal vein(splenic artery), the pancreas
Pancreas
The pancreas is a gland organ in the digestive and endocrine system of vertebrates. It is both an endocrine gland producing several important hormones, including insulin, glucagon, and somatostatin, as well as a digestive organ, secreting pancreatic juice containing digestive enzymes that assist...
, the left renal vein
Renal vein
The renal veins are veins that drain the kidney. They connect the kidney to the inferior vena cava.It is usually singular to each kidney, except in the condition "multiple renal veins".It also divides into 2 divisions upon entering the kidney:...
, the inferior part of the duodenum
Duodenum
The duodenum is the first section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear and the terms anterior intestine or proximal intestine may be used instead of duodenum...
, the mesentery
Mesentery
In anatomy, the mesentery is the double layer of peritoneum that suspends the jejunum and ileum from the posterior wall of the abdomen. Its meaning, however, is frequently extended to include double layers of peritoneum connecting various components of the abdominal cavity.-Mesentery :The...
, and aortic plexus
Aortic plexus
The abdominal aortic plexus is formed by branches derived, on either side, from the celiac plexus and ganglia, and receives filaments from some of the lumbar ganglia....
.
Posteriorly, it is separated from the lumbar vertebræ and intervertebral fibrocartilages by the anterior longitudinal ligament
Anterior longitudinal ligament
The anterior longitudinal ligament is a ligament that runs down the anterior surface of the spine. It traverses all of the vertebral bodies and intervertebral discs....
and left lumbar veins.
On the right side it is in relation above with the azygos vein
Azygos vein
The azygos vein is a vein running up the right side of the thoracic vertebral column. It can also provide an alternate path for blood to the right atrium by allowing the blood to flow between the venae cavae when one vena cava is blocked.-Structure:...
, cisterna chyli
Cisterna chyli
The cisterna chyli is a dilated sac at the lower end of the thoracic duct into which lymph from the intestinal trunk and two lumbar lymphatic trunks flow.-Flow of lymph:...
, thoracic duct
Thoracic duct
In human anatomy, the thoracic duct of the lymphatic system is the largest lymphatic vessel in the body. It is also known as the left lymphatic duct, alimentary duct, chyliferous duct, and Van Hoorne's canal....
, and the right crus of the diaphragm—the last separating it from the upper part of the inferior vena cava
Inferior vena cava
The inferior vena cava , also known as the posterior vena cava, is the large vein that carries de-oxygenated blood from the lower half of the body into the right atrium of the heart....
, 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
Small intestine
The small intestine is the part of the gastrointestinal tract following the stomach and followed by the large intestine, and is where much of the digestion and absorption of food takes place. In invertebrates such as worms, the terms "gastrointestinal tract" and "large intestine" are often used to...
.
Relationship with inferior vena cava
The abominal aorta's venous counterpart, the inferior vena cavaInferior vena cava
The inferior vena cava , also known as the posterior vena cava, is the large vein that carries de-oxygenated blood from the lower half of the body into the right atrium of the heart....
(IVC), travels parallel to it on its right side.
- Above the level of the umbilicusNavelThe navel is a scar on the abdomen caused when the umbilical cord is removed from a newborn baby...
, 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 arteryCommon iliac arteryThe common iliac arteries are two large arteries that originate from the aortic bifurcation at the level of the fourth lumbar vertebra. They bifurcate into the external iliac artery and internal iliac artery ....
to cross its opposite side counterpart (the left common iliac veinCommon iliac veinIn human anatomy, the common iliac veins are formed by the external iliac veins and internal iliac veins and together, in the abdomen at the level of the fifth lumbar vertebrae, form the inferior vena cava. They drain blood from the pelvis and lower limbs....
) anteriorly.
Collateral circulation
The collateral circulation would be carried on by the anastomoses between the internal thoracic arteryInternal thoracic artery
In human anatomy, the internal thoracic artery , previously known as the internal mammary artery , is an artery that supplies the anterior chest wall and the breasts...
and the inferior epigastric artery
Inferior epigastric artery
In human anatomy, inferior epigastric artery refers to the artery that arises from the external iliac artery and anastomoses with the superior 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
Inferior mesenteric artery
In human anatomy, the inferior mesenteric artery, often abbreviated as IMA, supplies the large intestine from the left colic flexure to the upper part of the rectum, which includes the descending colon, the sigmoid colon, and part of the rectum...
and the internal pudendal artery
Internal pudendal artery
The internal pudendal artery is an artery that branches off the internal iliac artery, providing blood to the external genitalia.The internal pudendal artery is the terminal branch of the anterior trunk of the internal iliac artery...
, when (as is more common) the point of ligature is below the origin of the inferior mesenteric artery
Inferior mesenteric artery
In human anatomy, the inferior mesenteric artery, often abbreviated as IMA, supplies the large intestine from the left colic flexure to the upper part of the rectum, which includes the descending colon, the sigmoid colon, and part of the rectum...
; and possibly by the anastomoses of the lumbar arteries
Lumbar arteries
The lumbar arteries are in parallel with the intercostals.They are usually four in number on either side, and arise from the back of the aorta, opposite the bodies of the upper four lumbar vertebræ....
with the branches of the internal iliac artery
Internal iliac artery
The internal iliac artery is the main artery of the pelvis.-Structure:The internal iliac artery supplies the walls and viscera of the pelvis, the buttock, the reproductive organs, and the medial compartment of the thigh...
.