A & P 2 - Cvs Circulatory Routes

Front 1

What are the divisions of the Aorta?

Back 1

Ascending Aorta:
-upward from LV
branches = L and R coronary A (supply heart)

Arch of Aorta:
-continuation of the ascending aorta that arches over heart to left
branches:
Brachiocephalic artery (trunk) - break into R common carotid (right side of head and neck) and R subclavian (upper right extremity)
Left Common Carotid A - supplies left side of head and neck
Left Subclavian A - left upper limb
Thoracic Aorta:
-from arch; 4th or 5th thoracic to diaphragm

Abdominal Aorta:
-from diaphragm (aortic hiatus)
-divides at L4 into 2 common iliac arteries

Front 2

What are the Vertebral arteries?

Back 2

R Vertebral Artery:
-branch of R subclavian
-enters skull through foramen magnum
-unites with L vertebral (branch of L subclavian) to form basilar A

Basilar A:
-middle of brainstem
-branches into posterior cerebral and cerebellar A

Front 3

What are the carotid arteries?

Back 3

Common carotid A:
R Common Carotid:
-begins at bifurcation of brachiocephalic trunk
-divides into internal and external carotid A
-PULSE can be determined here lateral to larynx
L Common Carotid:
-branch of aortic arch

External Carotid A:
-begins at superior larynx and ends at TMJ
-terminal branches = superficial temporal and maxillary arteries
-PULSE at superior border of larynx

Internal Carotid A:
-NO BRANCHES IN NECK
-enters skull at carotid foramen
-terminal branches = anterior cerebral and middle cerebral

Front 4

What is the Circle of Willis?

Back 4

-formed by branches of basilar (posterior cerebral), internal carotid (anterior and middle cerebral) connected with anastomoses - anterior and posterior communicating arteries

location = base of brain

function:
-alternate route for blood flow to the brain (ex. in occlusion) and equalize BP in brain arteries

Front 5

What are the branches of the R Axillary arteriy?

Back 5

R axillary A --> R brachial A --> R Radial A and R Ulnar A --> R superficial palmar (--> R common palmar digital --> R proper palmar digital) and R Deep palmar (--> R palmar metacarpal)

Front 6

What are the distribution of branches of the Thoracic Aorta?

Back 6

VIsceral Branches (visceral organs):
-Pericardial A - pericardium
-Bronchial A - bronchi, pleura, bronchial lymph nodes, esophagus
-Esophageal (4-5 A) - esophagus
-Mediastinal - mediastinum

Parietal Branches (thoracic wall):
-posterior intercostal A (9 Pairs) - intercostal and chest muscles (pec major, minor, serratus anterior), skin and subQ, mammary glands, vertebrae, meninges, spinal cord
-subcostal - similar to posterior intercostal
-superior phrenic - superior and posterior surface of diaphragm

Front 7

What are the distribution of branches in the Abdominal Aorta?

Back 7

Visceral branches:
Unpaired:
-Celiac Trunk - common hepatic A (stomach, duodenum, pancreas, greater omentum), L gastric A (stomach), Splenic A (largest branch, supplies spleen)

-Superior Mesenteric (L1) - inferior pancreaticoduodenal A (pancreas and duodenum), jejunum and ileal A (jejunum and ileum), ileocolic A (ileum and ascending colon), middle colic A (transverse colon), right colic A (ascending colon)

-Inferior Mesenteric (L3) - Left Colic A (transverse and descending colon), Sigmoid A (sigmoid and descending colon), Superior rectal A (rectum)

Paired:
-Suprarenal - supplies adrenal glands, only middle suprarenal arise directly from aorta

-Renal - at L2, supplies kidneys, adrenal glands, and ureters

-Gonadal - Testicular A (supply testes, epididymis, ureters), Ovarian A (supply ovaries, uterine tube and uterus)

Parietal Branches:
Unpaired:
-Median sacral - sacrum and coccyx

Paired:
-Inferior Phrenic - inferior surface of diaphragm and adrenal glands

-Lumbar - spinal cord and meninges, msucles and skin of lumbar region

Front 8

What are the terminal branches of the Abdominal Aorta?

Back 8

Common Iliac Artery

Internal Iliac A (primary arteries of the pelvis, supply uterus and prostate, muslcles of buttocks and thigh, urinary bladder, external genitalia

External Iliac A

Femoral A

Front 9

What are the veins of the head and neck?

Back 9

From head:
-Internal Jugular V - lateral to carotid A, unite with subclavian V --> brachiocephalic V --> SVC; drains blood from venous sinuses, face, and neck

-External Jugular V - begin in parotid gland near angle of mandible; go across SCM; terminate in subclavian vein; drain blood from face and scalp

-Vertebral V - originate in occipital condyles, go through transverse foramina of C1-C6; join brachiocephalic vein; drain deep structures of neck

blood from brain goes through dural venous sinuses and into internal jugular V

Front 10

What are the different dural venous sinuses?

Back 10

Superior Sagittal Sinus:
-from frontal to occipital lobes
-drains into right transverse sinus

Inferior Sagittal sinus:
-begins posterior to attachment of falx cerebri
-becomes straight sinus --> left transverse sinus

Straight Sinus:
-runs in tentorium cerebelli
-receives blood from cerebellum
-drains into left transverse sinus

Transverse Sinuses:
-begin near occipital bone
-become sigmoid sinus near temporal bone
-receive blood from cerebellum, cerebrum, and cranial bones

Sigmoid sinuses:
-located along temporal bones
-terminate in internal jugular veins

Cavernous sinuses:
-either side of sphenoid bone
-drains into transverse sinuses and internal jugular V
-CN III, IV and 2 branches of V, and carotid A pass through the sinuses

Front 11

What are the veins of the thorax?

Back 11

Brachiocephalic vein:
-drain blood from superior thorax, mammary glands, head. neck, and upper limbs
-unite to form SVC

Azygos system:
-drain most of thoracic structures
-serves as a bypass for IVC
3 veins:
-azygos - begins at junction of R subcostal and R asc. lumbar V; receives blood from hemiazygos, accessory hemiazygos, R post. intercostal, esophageal, mediastinal, pericardial, and bronchial V

-hemiazygos - drains into azygos and SVC; starts at junction of L subcostal and L asc. lumbar V; receives blood from post. intercostal, esophageal, mediastinal, and accessory hemiazygos

-accessory hemiazygos - drains into azygos V; receives blood from L posterior intercostal, L bronchial, and mediastinal V

empty into SVC

Front 12

What are the Veins that drain into the IVC?

Back 12

IVC:
-drains blood from abdominal and pelvic viscera, abdominal wall and lower limbs
-formed by 2 common iliac V

Lumbar veins:
-connect with R & L ascending lumbar V --> azygos or hemiazygos V

Renal V:
-drains kidneys
-L renal receives via L testicular/L ovarian V, L inferior phrenic, L suprarenal V

Suprarenal V:
-drain adrenal gland

Gonadal V:
-Testicular - drains testes
-Ovarian - drain ovaries

Hepatic V:
-hepatic portal vein brings deoxygenated nutrient rich blood from GIT and spleen to liver
-drains blood from liver to IVC

Front 13

What are the Iliac Veins?

Back 13

Internal Iliac V:
-drain the pelvis, external genitalia, buttocks, and thigh

External Iliac V:
-drain lower limb, abdominal wall, and cremaster mm in males

Front 14

What are characteristics of Hepatic Portal Circulation?

Back 14

GI and spleen capillaries --> Veins portal vein --> liver capillaries (sinuosoids)

oxygen blood mixes with deoxygenated blood in sinuosoids

R & L gastric and Cystic V empty into Hepatic Portal vein

Inferior mesenteric --> splenic --> hepatic portal vein

Superior mesenteric --> hepatic portal V

Front 15

What are characteristics of Fetal Circulation?

Back 15

-lungs, GI, and kidneys do not function until after birth

placenta:
-provides INTER EXCHANGE of gases
serves as:
-fetal gut (nutrients)
-fetal lungs
-fetal kidney
-versatile endocrine gland
-pathogenic barrier
-storage of proteins, glycogen, iron, polypeptides

umbilical vein:
-carries OXYGENATED band nutrient rich blood from placenta to fetus

2 umbilical arteries:
-branches of internal iliac (hypogastric) arteries
-returns deoxygenated blood from fetus to placenta

Front 16

What are the Fetal Shunts?

Back 16

4 LOW resistance shuts that all blood to bypass postnatal route

1. Placenta

2. Ductus Venosus (DV):
-continuation of umbilical vein
-bypasses liver, drains into IVC

3. Foramen Ovale (FO):
-opening in septum between 2 atria
-provides R-to-L shift of blood flow

4. Ductus Arteriosus (DA):
-connects pulmonary A w/ descending thoracic aorta
-contains smooth muscle which is relaxed by prostaglandins (PGE2)

-keeps heart to pump blood parallel

-mixing of outputs of 2 sides (oxygenated and deoxygenated) --> combined cardiac output (CCO)

Front 17

What are some changes in the CVS after birth?

Back 17

-placenta shed from mother

-umbilical arteris, vein, and placenta stop functioning

-umbilical arteries --> fibrous cord = medial umbilical ligament
-umbilical vein --> ligamentum teres (round ligament)

DV no longer needed --> ligamentum venosum

closure of foramen ovale:
-opening of pulmonary circulation --> decrease pressure in RA
-increase pressure in LA
-functional closure of small valve over FO, requires 3-9 months

Patent Foramen Ovale (10-20 % adults):
-if atrial septum doesnt close properly
-works like flap valve when increased pressure in chest
ex. during bowel movement, cough, or sneeze

Front 18

What are characteristics of the development of blood vessels?

Back 18

common precursor is hemangioblast:
-angioblasts = blood vessels
-pluripotent stem cells = blood cells (3 weeks after fertilization)

Angioblasts:
-blood islands
-formation of spaces in island = lumen
differentiation of angioblasts:
-cells around lumen --> endothelium
-cells around endothelium --> tunics of vascular wall

Growth and fusion of blood islands --> network of blood vessels through the embryo