Anatomy Exam 4: Development Of Cardiovascular System

Front 1

The _________________ are 5 paired structures arising from the aortic sac (most distal portion of truncus arteriosus)

Back 1

aortic arches

Front 2

The aortic arches are embedded in mesenchyme of the _______________________, each terminates into the R & L _________________

Back 2

mesenchyme of the pharyngeal arches

R & L dorsal aorta

Front 3

How are the aortic arches numbered?

Back 3

I-IV & VI , cranial to caudually
(NO 5!!)

Front 4

The __________ forms the R & L horns, giving rise to the______________artery & ____________ aorta.

Back 4

aortic sac

R- brachiocephalic artery
L- proximal (ascending) aorta

Front 5

Derivatives of the ___ arch forms the common carotid, external carotid artery & part of the internal carotid artery?

Back 5

3rd arch

*rest of internal from dorsal aorta

Front 6

Derivatives of the ___ arch form part of the arch of the aorta (on the L) & the proximal segment of the right subclavian (on the R)

Back 6

4th arch

Front 7

Derivatives of the ___ arch form the proximal segment of the right pulmonary artery (on the R) & the proximal segment of the left pulmonary artery & the ductus arteriosus (on the L).

Back 7

6th

Front 8

What does the ductus arteriosus do?

Back 8

shunts blood from the left pulmonary artery to the aorta (pulmonary circulation to systemic circulation)

Front 9

The distal portions of the 6th arches become what nerves?

Back 9

recurrent laryngeal nerve (CN X)

Front 10

How does the R recurrent laryngeal nerve migrate from R 6th arch during development?

Back 10

migrates cephalically & hooks (recurs) around the right subclavian artery

Front 11

How does the L recurrent laryngeal nerve migrate from L 6th arch during development?

Back 11

no cephalic movement bc of ductus arteriosus

Front 12

The ductus arteriosus closes shortly after birth (lung inflation) and forms what?

Back 12

the ligamentum arteriosum

Front 13

Describe the following cardiovascular anomalies:
patent ductus arteriosus-

Back 13

patent ductus arteriosus- failure of ductus arteriosus to close
leads to:
left-to-right shunt & pulmonary hypertension

Front 14

Describe the following cardiovascular anomalies:
preductal coarcation of the aorta-
postductal coarcation of the aorta-

Back 14

preductal coarcation of the aorta- narrowing aorta above ductus arteriosus
-surgery required for survival
*usually associated w/ patent ductus arteriosus

postductal coarcation of the aorta- narrowing of aorta below ductus arteriosus
-collateral circulation develops
-pts survive into adulthood but usually need surgery after age 50

Front 15

Describe the following cardiovascular anomalies:
-double aortic arch-

Back 15

double aortic arch- right dorsal aorta persists, vascular ring is formed around the trachea and esophagus
causes:
difficulty breathing (dyspnea)
difficulty swallowing (dysphagia)

Front 16

The vitelline arteries, which initially supply the yolk sac (paired), fuse to form what?

Back 16

form three arteries (unpaired) in the dorsal mesentary gut:
celiac artery (foregut)
superior mesenteric artery (midgut)
inferior mesenteric artery (hindgut)

Front 17

The umbilical arteries are initially paired ventral branches of the dorsal aorta. They shift to become branches of the common illiac arteries. After birth what do they become?

Back 17

internal illiac & umbilical arteries

*distal umbilical arteries become medial umbilical ligaments

Front 18

The venous system develops from ___ major pairs of veins in week ___ of embryo development

Back 18

3 major pairs

week 5

Front 19

The 3 major pairs of veins are:

Back 19

1. Vitelline (omphalomesenteric) veins-
carry blood from yolk sak to sinus venosus

2. Umbilical veins-
carry oxygenated blood to embryo from chorionic villi

3. Cardinal veins-
drain body of embryo proper

Front 20

Before entering the sinus venosus the vitelline veins from a plexus around the duodenum & pass through the ___________

What does the plexus eventually develop into?

Back 20

septum transversum



portal vein

Front 21

The vitelline veins form _________ when liver cords grow into the septum transversum

Back 21

hepatic sinusoids

Front 22

What does the right side of the vitelline vein form?

(left side largely disappears)

Back 22

the hepatocardiac portion of the inferior vena cava & superior mesenteric vein

Front 23

The _____________ veins initially pass on each side of the liver, connecting the hepatic sinusoids.

Back 23

umbilical veins

Front 24

The right umbilical v & proximal part of left umbicial V disappear leaving the left umbilical vein as the only route carrying blood from the the placenta to where?

Back 24

placenta to the liver

Front 25

The ductus venosus froms btwn the L umbilical v & R hepatocardiac channel (inferior vena cava), what does this do?

Back 25

shunts most of the oxygenated blood from placenta PAST liver to heart

*doesnt need to go to fetal liver

Front 26

After birth, what do the following obliterate into:
left umbilical vein
ductus venosus

Back 26

left umbilical vein--> ligamentum teres hepatis
ductus venosus--> ligamentum venosum

Front 27

The anterior and posterior cardinal veins join to form the common cardinal vein. What do the anterior & posterior drain individually? What does the common cardinal vein drain into?

Back 27

anterior cardinal- cephalic part of embryo
posterior cardinal- rest of embryo

common cardinal- drains into sinus horn

Front 28

During weeks 5-7 the following form, what do they drain?
subcardinal veins
supracardinal veins
>azygos vein
>hemiazygos vein
sacrocardinal veins

Back 28

subcardinal- drains kidneys

supracardinal- drain body wall via intercostal veins, R becomes azygos, L becomes hemiazygos

sacrocardinal- drains lower extremity

Front 29

The R anterior cardinal & common cardinal veins form the _________________

Back 29

superior vena cava

Front 30

The anastomosis btwn the anterior cardinal veins develops into the ____________

Back 30

left brachiocephalic vein

Front 31

The terminal portion of the L posterior cardinal veins forms the _________

Back 31

left superior intercostal veins

Front 32

The right subcardinal vein develops into the _________________

Anatsomosis btwn the subcardinal veins forms the _______________

Back 32

renal segment of the inferior vena cava


left renal veins

Front 33

The proximal portion of the left subcardinal vein disappears & the distal portion forms the ___________

Back 33

left gonadal vein

Front 34

The anastomosis btwn the sacrocardinal veins forms the _________________________________

The right sacrocardinal vein becomes the_________________

Back 34

left common illiac vein


sacrocardinal sement of the inferior vena cava

Front 35

The inferior vena cava has segments derived from what veins?

Back 35

vitelline
subcardinal
sacrocardinal

Front 36

Blood returns to the fetus, 80% saturated w/ O2, via what?

Back 36

umbilical vein

Front 37

Most of the blood in the umbilical vein bypasses the liver via the _______________________ and flows directly into the inferior vena cava

Back 37

ductus venosus

Front 38

T/F
the inferior vena cava (IVC) contains oxygenated blood only

Back 38

FALSE

placental blood mixes w/ deoxygenated blood from the lower limbs before entering right atrium

Front 39

In the right atrium, most of the blood from the IVC passes through the ____________ and goes directly into the left atrium

Back 39

foramen ovale

Front 40

When blood leave the right ventricle via the pulmonary trunk, most of it flows into __________________

Back 40

majority flows into arch of aorta via ductus arteriosus
(rather than to lungs via pulmonary arteries)

Front 41

After coursing through the descending aorta, 58% O2 saturated blood flows to the placenta via ______________

Back 41

two umbilical arteries

Front 42

Upon taking one's first breath, blood pressure in right atrium falls below that in left creating a pressure differential. What does this pressure do?

Back 42

holds foramen ovale shut

Front 43

Eventually the valve of the foramen ovale will fuse with the septum secundum and form the ________________

Back 43

fossa ovalis

(20% ppl dont fuse= probe patency)

Front 44

What are the main circulatory changes that occur after birth?

Back 44

-distal umbilical arteries close & form medial umbilical ligaments
-closure of the umbilical vein forms ligamentum teres hepatis
-closure of ductus venosus forms ligamentum venosum
-ductus arteriosus closes to form ligamentum arteriosum
-foramen ovale closes and forms the fossa ovalis

Front 45

In the fetal heart, intention blood shunting will always be left to right or right to left?

Back 45

right to left!!

Front 46

In an adult heart, an anomality that results in shunting will lead to more severe symptoms if the blood is shunted right to left or left to right? Why?

Back 46

Right to left!!!

allows deoxygenated blood into arterial flow, reducing oxygen delivery to body

Front 47

What are some examples of defects that cause right to left shunting?

Back 47

Tetralogy of Fallot
Transposition of the great arteries (right ventricular aorta & left ventricular pulmonary trunk)

Front 48

What does left to right shunting cause?
What are some examples of defects that cause left to right shunting?

Back 48

allows some of the oxygenated blood the be lost from arterial flow, doesn't cause any extreme immediate issues.

patent ductus arteriosus (PDA)

atrial septal defect (ostium secundum defect, patent foramen ovale)

ventricular septal defect (membranoue portion defect)

Front 49

What is the main factor contributing to the direction of shunted blood.

Back 49

Usually blood will be shunted away from the higher pressure = left to right shunting

Sometimes pressure differential will be overridden by large structures that direct flow = right to left shunting

Front 50

What is the difference between cyanotic and non-cyanotic defects?

Back 50

Cyanotic defects- (early cyanotic) are caused by right to left shunting
compromises oxygenated blood supply, leads to hypoxia=cyanosis

Non-cyanotic- (late cyanotic) defects cause left to right shunting
lose some of arterial blood, but supply remains oxygenated, no immediate effects