5. Development Of The Heart & Great Vesssels

Question 1

What is the worldwide incidence of congenital heart defects ?

Answer 1

1% of live births

Question 2

What percentage of people with congenital heart defects survive until adulthood ?

Answer 2

90%

Question 3

Are medications used to treat heart disease teratogenic?

Answer 3

Yes, highly

Question 4

What is the most common cause of indirect maternal death ?

Answer 4

Congenital heart defect

Question 5

What are the zones of the primitive heart tube in direction of blood flow?

Answer 5

Sinus venosus 
Primitive atrium 
Primitive ventricle 
Bulbus cordis
Truncus arteriosius
Aortic roots

Question 6

Why is the right atrium rough ?

Answer 6

Because it is mainly derived from the primitive atrium (which is rough trabeculated tissue)

Question 7

Why is the left atrium smooth ?

Answer 7

Because it is mainly derived from the proximal primitive pulmonary vein (which is a vessel..so smooth!)

Question 8

Which embryonic tissue is the right atrium mainly derived from ?

Answer 8

Primitive atrium

Question 9

Which embryonic tissue is the left atrium mainly derived from ?

Answer 9

Proximal Primitive pulmonary vein

Question 10

Once developed Which atrium has a rough trabeculated wall?

Answer 10

Right atrium

Question 11

Where does gas exchange happen in a foetus ?

Answer 11

Placenta

Question 12

What are two differences between foetus and mature circulatory system ?

Answer 12

• Foetus lungs do not exchange gas

- Foetus circulatory system requires shunts to move move to right place.

Question 13

How many shunts are there in the foetus?

Answer 13

3

Question 14

What is the shunt at the right atrium called ?

Answer 14

Foramen ovale

Question 15

What is the shunt at the lung called ?

Answer 15

Ductus venosus

Question 16

What is the shunt at the pulmonary trunk called?

Answer 16

Ductus arteriosus

Question 17

What is the remnant of ductus arteriosus ?

Answer 17

Ligamentum arteriosum

Question 18

Where does foramen ovale shunt blood from and to?

Answer 18

RA -LA

Question 19

Where does ductus venosus shunt blood from and to?

Answer 19

Liver - inferior vena cava

Question 20

Where does ductus arteriosus shunt blood from and to?

Answer 20

Pulmonary trunk to aorta

Question 21

What causes the foramen ovale to close?

Answer 21

Pressure increase in LA - result of first breath

Question 22

What causes the ductus venosus to close?

Answer 22

Removal of placental support

Question 23

What causes the ductus arteriosus to close?

Answer 23

Muscular contraction

Question 24

What’s does the 4th arch in the primitive aorta form ?

Answer 24

Right side - proximal R.subclavian artery

Left side - arch of aorta

Question 25

What does the 6th arch of the primitive aorta form ?

Answer 25

Right side - R pulmonary artery | Left side - L pulmonary artery + ductus ateriosus

Question 26

What is the name of the nerve that hooks itself under the ductus ateriosus ?

Answer 26

Laryngeal nerve

Question 27

If the ductus ateriosus fails to close after birth.. What is this called? Which direction will the blood shunt ?

Answer 27

Patent ductus arteriosus Left to right

Question 28

What are the 2 leaflets of the intra atrial septum called ?

Answer 28

Septum Primum | Septum secundum

Question 29

What are the names of the 2 holes formed in the leaflets of the atrial septum?

Answer 29

Ostium secundum | Foramen ovale

Question 30

What are the 2 septum of the atria and their corresponding holes called?

Answer 30

Septum Primum - Ostium Secundum | Septum Secundum - foramen ovale

Question 31

What is hypoplastic left heart syndrome ?

Answer 31

Congenital Underdeveloped left ventricle

Question 32

What area has the most common cardiovascular congenital defect ?

Answer 32

Ventricle septum

Question 33

What are the 2 components of the ventricular septum?

Answer 33

Muscular | Membranous

Question 34

What makes up most of the ventricular septum...membrane component or muscular component ?

Answer 34

Muscular

Question 35

Both the atrial and ventricular septum grow in relation to which structure ?

Answer 35

Endocardial cushion

Question 36

After the muscular portion of the ventricular septum is formed what is the gap left behind called?

Answer 36

Interventricular foramen.

Question 37

What closes up the interventricular foramen ?

Answer 37

Membranous portion of ventricular septum

Question 38

How is the membranous portion of the ventricular septum formed?

Answer 38

Connective tissue from endocardial cushion

Question 39

In a ventricular septum defect which part of the septum is most commonly involved ?

Answer 39

Membranous

Question 40

How is a septum formed in truncus arteriosus ? What does this septum lead to ?

Answer 40

Endocardial cushions come together and join to form a spiral septum in the truncus arteriosus Results in aorta and pulmonary trunk

Question 41

What is transposition of the great vessels ?

Answer 41

Congenital defect in which the aorta arises from the right ventricle & the pulmonary trunk arises from the left ventricle

Question 42

What forms the endocardial cushions ?

Answer 42

Neural crest cells

Question 43

Endocardial cushions are related to formation of what structures ?

Answer 43

Atrial septum Ventricular septum Trunkus arteriosus septum

Question 44

What are the 4 defects in tetralogy of fallot?

Answer 44

PULMONARY TRUNK OBSTRUCTION OVERRIDING AORTA SEPTAL DEFECT (VENTRICLE) HYPERTROPHY OF RIGHT VENTRICLE

Question 45

What are neural crest cells very sensitive to ?

Answer 45

Alcohol