CVS 3 Embryology Flashcards

1
Q

What are the relative pressures in the atria in utero?

A
  • Right atrial pressure > left atrial pressure
  • Oxygenated blood from the placenta arrives to the RA via the umbilical vein draining into the IVC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What germ layer does the heart and vessels arise from?

A

Mesoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How does folding of the embryo in the 4th week change the position of the caridogenic field?

A

Moves it caudal to the oropharyngeal membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the parts of the heart from cranial to caudal?
What do they give rise to?

A
  • Truncus arteriosus: pulmonary trunk + aortic arch
  • Bulbous cordis: RV + R+L outflow tracts
  • Primitive ventricle: LV
  • Primitive atrium: RA+LA
  • Sinus venosus:
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the inflow and outflow of the initial developing heart

A

Inflow at caudal end
Outflow at cranial end

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

When is the midline heart tube formed?

A

3 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What layer of the pericardium touches the heart?

A

Visceral layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the transverse sinus?

A

Gap between arteries and veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the oblique sinus?

A

Space within pericardial cavity behind heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the adult atrium formed from?

A

Rough part - primitive atrium
Smooth part - Sinus venosus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where does the SAN form from?

A

Sinus venosus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What forms from the 4th aortic arch?

A

Left - aortic arch
Right - right subclavian artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What forms from the 3rd aortic arches?

A

Right - Carotid arteries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What forms from the 6th aortic arch?

A

Left - pulmonary artery + ductus arteriosus
Right - pulmonary artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why is there not a 5th aortic arch?

A

5th aortic arch degenerates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens to the 6th aortic arch on the right side?

A

Not needed so degenerates + disappears

17
Q

What are the fetal shunts?

A

Ductus venosus - by passes the liver
Ductus arteriosus - bypasses the lungs
Foramen ovale - RA > LA

18
Q

What happens to ductus venosus after birth?

A

Becomes ligamentum venosum

19
Q

What happens to ductus arteriosus after birth?

A

Ligamentum arteriosus

20
Q

What happens to foramen ovale after birth?

A

Fossa ovalis

21
Q

What are the septums involved in splitting the heart into 4 chambers?

A
  • Outflow septum > splits into aorta + pulmonary trunk
  • Interventricular septum > R+L ventricle
  • Atrioventricular septum > forms V valves
  • Interatrial septum > R+L atrium
22
Q

What forms the AV valves?

A

Endocardial cushions meeting to form tricuspid + mitral valve

23
Q

Outline the process of atrial septation

A
  • septum primum grows down from atrial wall
  • ostium primum- gap below septum primum
  • septum primum grows to endocardial cushion
  • ostium secundum appears in middle to allow R > L shunt
  • septum secundum grows down from atrial wall to right of septum primum&raquo_space; creates foramen ovale
  • RA pressure > LA pressure so foramen ovale remains open - R >L shunt in utero
24
Q

What happens to foramen ovale after birth?

A

LA pressure > RA pressure
Septum primum presses against septum secundum
Foramen ovale closes

25
Q

Where do most ventricular septal defects occur?

A

Membranous component of ventricles

26
Q

Outline ventricular septation

A
  • Membranous component grows down from endocardial cushions
  • Muscular component grows up from muscular wall
  • Both components meet to form septum
27
Q

What are the derivates of the aortic arches?

A

1+2 - none
3 - common, internal + external carotid arteries
4 - aorta L + subclavian artery R
6- pulmonary arteries

28
Q

Route of the right and left recurrent laryngeal nerves

A
  • left: under arch of aorta
  • right: under right subclavian artery
29
Q

How is the aorta + pulmonary trunk formed?

A

Truncus arteriosus is divided by the outflow septum

30
Q

What does Truncus arteriosus become?

A

Pulmonary trunk
Aortic arch

31
Q

What is the physiological and pathological importance of the right auricle of the heart?

A
  • physiological: muscular pouch that increases the RA capacity
  • pathological: in AF patients, stasis of blood can occur > clot formation > stroke