Development of the Great Vessels

Question 1

what helps with vessel repair?

Answer 1

angiogenesis

Question 2

what do aortic arches arise from

Answer 2

aortic sac (appear cranial->caudal), not simultaneously

• terminate in the R and L dorsal aorta
• begin appearing around week 4

Question 3

arch I derivatives

Answer 3

maxillary a

Question 4

arch II derivatives

Answer 4

stapedial a (middle ear)

Question 5

arch III derivatives

Answer 5

common, int, and ext carotid a

Question 6

arch IV derivatives

Answer 6

L: part of aortic arch
R: prox portion of subclavian

Question 7

arch VI derivatives

Answer 7

L: L pulm a and ductus arteriosus (shunts blood from pulm vasc to aortic vasc)
R: R pulm a

Question 8

arch VII derivatives

Answer 8

L: L subclavian a
R: R distal portion of subclavian a

Question 9

what is the L horn of aortic sac

Answer 9

prox portion of aortic a

Question 10

when are all great vessels developed and assembled by

Answer 10

week 8

Question 11

path of R and L recurrent laryngeal nn

Answer 11

R: loops under R subclavian
L: loops under arch of aorta

Question 12

what do most somatic aa of trunk develop from

Answer 12

intersegmental aa from dorsal aa

• develop 1. intercostal aa
  2. lumbar aa

Question 13

vitelline a

Answer 13

• initially are number if paired vessels supplying the yolk sac and initiate there
• develop 1. cilia a (tr) 2. superior mesenteric a

Question 14

umbilical a

Answer 14

• initially paired ventral brs off dorsal aorta, course to placenta from embryo
• develops 1. inf mesenteric a 2. forms secondary connection with dorsal aorta->common iliac a

Question 15

coronary aa

Answer 15

derived from epicardium

-connection to aorta is formed by ingrowth of arterial endothelial cells

Question 16

embryonic venous system

Answer 16

3 pairs of major vv

1. vitelline vv: drains GI tract and gut derivatives
2. umbilical vv: oxygenated blood from placenta to embryo
3. cardinal vv: draining head, neck, and body wall

Question 17

vitelline vv

Answer 17

• forms plexus around duodenum and pass thru septum transversum before entering sinus venosus
• liver chords growing into septum interrupt the course and form hepatic sinusoids
• network around duodenum wall form a single vessle->hepatic portal v

Question 18

what happens when the L sinus horn reduces

Answer 18

1. rechannels blood from L side of liver to R
2. R vitelline duct enlarges (forms part of IVC, sup mesenteric v)
3. R-L anastamoses remodel to drain into portal v as splenic v and inf mesenteric v

Question 19

umbilical vv

Answer 19

-R will regress and obliterate
L witll lose connection to sinus horn and form ductus venosus (bypass sinusoidal plexus of the liver, drain blood directly into the IVC)

Question 20

cardinal vv

Answer 20

• drains embryo “proper”

- consists of ant (drains cephalic pt), post (drains rest of embryo), and common cardinal vv

Question 21

what supplements and then replaces post cardinal vv

Answer 21

sub/supracardinal vv

Question 22

what does caudal remnant of post cardinal vv develop into

Answer 22

common iliac v and sacral portion of IVC

Question 23

ant cardinal vv

Answer 23

• cranial portions give rise to IJVs
• capillary plexus in face rise to EJVs
• forms brachiocephalic vv
• sup vena cava formed by R common cardinal and prox portion of R ant cardinal

Question 24

abdominal portion of supracardinal vv

Answer 24

• inf portion of L obliterates

- R and subcardinal anastamose to form a segment of IJV

Question 25

thoracic portion of supracardinal vv

Answer 25

L thor supracardinal = hemiazygos v

-remaining portion of inf R supracard drains to heart (azygos v)

Question 26

subcardinal vv

Answer 26

• forms renal vv and gonadal vv
• longitudinal segments of L regress after forming anastamoses
• R forms portion of renal segment of IVC

Question 27

6 primary lymphatic sacs

Answer 27

2 jugular
2 iliac
1 retroperitoneal
1 cisterna chyli

Question 28

development of lymphatic system

Answer 28

• vessels will connect to the sac and pass along main vv
• R and L thoracic ducts initially connect the jugular sacs with cisterna chyli
• thoracic duct = caudal R lymphatic duct and anastamosis of R and L cranial thor ducts
• R lymphatic duct = cranial portion of the R thor duct