From the left atrium, blood moves into the left ventricle, which pumps blood into the aorta. The aorta and its branches—the systemic arteries —send blood to virtually every organ of the body Figure 3.
Systemic Arteries. The major systemic arteries shown here deliver oxygenated blood throughout the body. Systemic arteries are the arteries including the peripheral arteries , of the systemic circulation, which is the part of the cardiovascular system that carries oxygenated blood away from the heart, to the body, and returns deoxygenated blood back to the heart. The largest artery is the aorta , the main high-pressure pipeline connected to the heart's left ventricle.
The aorta branches into a network of smaller arteries that extend throughout the body. The arteries' smaller branches are called arterioles and capillaries. Arteries are blood vessels responsible for carrying oxygen-rich blood away from the heart to the body. Veins are blood vessels that carry blood low in oxygen from the body back to the heart for reoxygenation.
The left common carotid, and the left subclavian artery, come directly off the aortic arch. However, there are two brachiocephalic veins. It feeds blood flow to the right carotid artery and the right subclavian artery. It is also known as the innominate artery or the brachiocephalic trunk.
The name refers to the fact that blood flows through this very short artery to the arm brachio and the head cephalic. Celiac artery , also known as the celiac axis or celiac trunk , is a major visceral artery in the abdominal cavity supplying the foregut. It arises from the abdominal aorta and commonly gives rise to three branches: left gastric artery , splenic artery , and common hepatic artery. The abdominal aorta is the part of the aorta that passes through the abdominal cavity.
Important branches of the abdominal aorta include the arteries that supply blood to the. Intestine celiac artery and superior and inferior mesenteric arteries. A visceral artery aneurysm is a ballooning of a portion of the splenic, renal, hepatic or mesenteric arteries.
These arteries supply blood to the spleen, kidney, liver and intestines, respectively. Aneurysms are the result of weakening and thinning of the artery wall.
Also, the internal iliac artery supplies the gluteal region, medial thigh, and perineal areas. Each internal iliac artery has a length of 4 cm. They begin as a common iliac artery and then bifurcates into the external and internal iliac arteries. This bifurcation occurs at the level of L5 and S1. The internal iliac artery then descends posteromedially into the lesser pelvis going medial to the external iliac artery and obturator nerve.
Close to the level of the greater sciatic foramen, the internal iliac then divides into an anterior and posterior trunk. The anterior division mainly supplies visceral structures like the bladder, rectum, and reproductive organs. The internal iliac artery continues down as the umbilical artery prenatally and connects to the placenta providing nutrition to the fetus.
This vessel then becomes occluded at birth and becomes the fibrous cords called medial umbilical ligaments. The next branch is the obturator artery, which passes between the obturator vein and nerve. The obturator artery gives off muscular branches, a branch to the ileum, and a pubic branch. The inferior vesical arteries in males and the vaginal arteries in females supply the inferior portion of the bladder and the pelvic urethra. Additionally, the inferior vesical artery supplies the prostate, and the vaginal artery supplies the superior part of the vagina.
The uterine artery is an additional branch of the internal artery in females and supplies the uterus, uterine tubes, ovaries, and superior vagina together with the vaginal artery. The middle rectal artery, another branch of the internal iliac, supplies parts of the rectum as well as the seminal glands and prostate.
The last two branches of the internal iliac artery are the internal pudendal artery and the inferior gluteal artery. The internal pudendal artery passes through the pudendal canal, and as it exits divides into its terminal branches, the perineal artery and the dorsal artery of the penis and clitoris.
The inferior gluteal artery supplies the skin and muscles of the buttocks and the posterior area of the thigh. The posterior branch of the internal iliac artery has three branches to include the iliolumbar, lateral sacral, and superior gluteal arteries.
The iliolumbar artery supplies the quadratus lumborum and psoas major. The lateral sacral arteries give off spinal branches that supply the spinal meninges. It may also give off some branches that supply the erector spinae and skin overlying the sacral area. Lastly, the superior gluteal artery supplies the muscles of the buttocks. The other main arteries of the pelvis include the ovarian artery, median sacral, and superior rectal arteries.
The ovarian artery initiates from the abdominal aorta, inferior to the renal artery. In its course, it runs anterior to the ureter. As it enters the lesser pelvis and crosses the external iliac vessels, it gives off an ovarian branch and a tubal branch supplying the ovaries and uterine tubes.
The median sacral artery originates from the posterior part of the abdominal aorta and gives branches to the lumbar vertebra, sacrum, and coccyx. Lastly, the superior rectal artery is a continuation of the inferior mesenteric artery and, at the level of S3 divides into two branches and supplies the superior part of the rectum and internal anal sphincter.
The inferior vena cava is the systemic drainage, which is formed by the anastomosis of the two common iliac veins at L5. This large vessel only drains the lower rectum and anal canal from the gastrointestinal tract. All the drainage from the abdominal viscera above the pectinate goes through the liver from the hepatic portal vein and then into the sinusoids to the liver.
From the hepatic sinusoids, the venous blood drains to the hepatic veins, then into the inferior vena cava, and directly into the right atrium to be oxygenated. The portal vein drains all the veins from the abdominal part of the gastrointestinal tube except for the lower part of the rectum and anal canal.
It also drains the veins coming from the spleen, pancreas, and gall bladder. The portal vein is 8 cm. The portal vein tributaries anastomose with the tributaries of inferior vena cava at different sites in the body, and these sites are called portocaval anastomosis. These sites are quite relevant clinically and are at the lower end of the esophagus, the bare areas of the liver, at the umbilicus, the falciform ligament accessory portal system of Sappey , the fissure for the ligamentum venosum, behind the peritoneum, lower end of the rectum and anal canal.
The pelvic venous outflow forms by the confluence of adjoining veins in the pelvic area. The various plexuses mainly drain into the internal iliac vein with some draining into the superior rectal vein and go to the hepatic portal system. Another minor path fo venous drainage for females is the ovarian vein. The superior gluteal veins are the biggest tributaries to the internal iliac veins. The primary nerves in the anterolateral wall are the thoracoabdominal nerves, which originate from T7-T11 and supply the anterolateral abdominal wall muscles and overlying skin.
Next, are the lateral cutaneous branches which come from T7-T9 and supplies the skin over the right and left hypochondriac regions. Then there are the subcostal nerves that come from the anterior rami of T12, which also supplies the muscles of the anterolateral abdominal wall to include the most inferior portion of the external oblique muscles along with the overlying skin.
Lastly, we have the iliohypogastric and ilioinguinal nerves, which are terminal branches of L1. The iliohypogastric supplies the skin overlying the upper iliac, inguinal, and hypogastric regions. The ilioinguinal supplies the lower inguinal regions, mons pubis, and anterior scrotal area. The main innervation of the pelvis comes from the sacral and coccygeal nerves. There is also some aid coming from the autonomic nervous system.
The obturator nerve forms from the anterior rami of L2-L4 and enters the pelvis. It passes through the obturator foramen, where it divides into its anterior and posterior parts.
There are no pelvic structures supplied by the obturator nerve. The lumbosacral trunk is a thick nerve that forms as the L4 unites with the anterior ramus of the L5.
This trunk will then join the sacral plexus. The sacral plexus is located at the posterolateral wall of the lesser pelvis. It gives rise to two primary nerves, namely the sciatic and pudendal nerves.
The sciatic nerve is the thickest of the nerves of the body and forms by the anterior rami of L4-S3. It descends and supplies the posterior aspect of the thigh and the leg and foot. The pudendal nerve is the key nerve of the perineum. It is also the chief sensory nerve of the external genitalia.
The coccygeal plexus is a tiny network of nerves that come from the anterior rami of S4 and S5. It supplies part of the pelvic diaphragm. The circle of Willis is formed by two group of arteries - the internal carotid arteries and two vertebral arteries. These arteries provide the anterior and posterior circulation of the brain respectively.
What is the difference between paired and unpaired arteries? Category: medical health heart and cardiovascular diseases. Of the visceral branches, the celiac artery and the superior and inferior mesenteric arteries are unpaired , while the suprarenals, renals, internal spermatics, and ovarian are paired. Of the parietal branches the inferior phrenics and lumbars are paired ; the middle sacral is unpaired. The terminal branches are paired.
Which artery is the largest and why? What is the longest vein in the body? Great Saphenous Vein. How many brachiocephalic arteries are there? What organs does the aorta supply blood to? What are the three branches of aorta? What artery is in the stomach? What artery carries blood to the intestines? How many aortas are there? What is the function of the gonadal artery? What is the function of the common iliac artery? What is the major systemic artery? What is the gonadal artery? What is meant by Venae Comitantes?
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