Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CVS II > Development > Flashcards

Development Flashcards

1
Q

What’s the incidence + mortality of congenital heart disease?

A

8/1000 births (25% of birth defects)

30-50%

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

What are the incidences of different defects of CHD?

A 
-Ventricular septal defects (VSD):
Membranous 9.9%
Muscular 4.7%
-Pulmonary stenosis (PS) 3.8%
-Atrioventricular septal defects (AVSD) 3.3%
-Atrial septal defects (ASD) 3.2%
-Transposition of great arteries (TGA) 2.6%
-Tetralogy of Fallot (ToF) 2.6%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

When does the heart develop?

A

weeks 3-10 post-conception

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

What’s the cardiac crescent derived from?

A

mesodermal cells

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

How’s the heart 1st recognised by?

A

crescent-shaped tube of myocardium

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

Whats the lumen of the crescent-shaped tube lined by?

A

endocardium

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

Describe the process of expansion of the primary heart tube

A
  • medial part of crescent expands (becoming L ventricle)

- endocardial tube attaches to developing aortic arches cranially (outflow) + systemic veins caudally (inflow)

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

Describe the process of elongation of the heart tube

A
  • cells from 2nd heart field are added at outflow +inflow
  • tube ends are fixed, so heart bends as it elongates
  • direction of looping is genetically controlled (leftward)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What’s between the heart tube myocardium + endocardium?

A

cardiac jelly which is an acellular layer

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

What’s ‘looping’?

A

ends of tube are fixed to vessels in embryo so heart must bend as it elongates

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

Why do the ventricles come in front of the atria?

A

heart loops so much

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

Summary of early heart development:

A
  • tube formation – muscle wrapped around endothelium
  • tube attached to arteries + veins at diff ends
  • tube elongates by adding cells at each end from 2nd heart field
  • tube bends, loops, coils
  • neural crest cells migrate into outflow region forming outflow cushions
  • epicardium cells come from proepicardial organ forming epicardium (visceral serous pericardium)
  • tube divided by partitioning into chambers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How are the primitive chambers formed?

A

expansion (ballooning) of tube

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

How are the ventricles characterised by?

A

trabeculae

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

Define septation

A

dividing the heart tube

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

What’s atrioventricular septation?

A

Atria from ventricles via AV cushions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What’s atrial septation?

A

L from R atrium via 1ᵒ interatrial septum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What’s ventricular septation?

A

L from R ventricle via interventricular septum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What’s outflow tract septation?

A

Pul artery from aorta via OFT cushions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does the mitral valve develop?

A

Inferior + superior AV cushion fuse together leaving a hole/channel on each side. L is mitral orifice -> mitral valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How does the tricuspid valve develop?

A

Inferior + superior AV cushion fuse together leaving a hole/channel on each side. R is tricuspid orifice -> tricuspid valve

22
Q

What’s AVSD’s?

A

common AV junction common in down’s syndrome 40%

23
Q

What orifice does the L atrium have?

A

pul vein

24
Q

What orifice does the R atrium have?

A

systemic venous sinus

25
Q

Why doesn’t the 1ᵒ interatrial septum fuse w AV septum in embryonic heart?

A

gaining O2 from mothers lungs via placenta so it diverts blood coming from RA into LA, then around the body. Pul circulation bypassed in early life

26
Q

Describe the process of atrial septation

A
  • 1ᵒ interatrial septum grows down fusing w AV cushions
  • trailing edge of 1ᵒ septum breaks down allowing blood flow from R –> L atrium
  • septum secundum grows down forming flap valve
  • L atrial pressure increases after birth, closes valve, seals
27
Q

What’s ostium secundum?

A

in 1ᵒ interatrial septum + forms as 1ᵒ interatrial septum closes

28
Q

What’s foramen ovale?

A

in septum secundum
bypass circuit - blood from body of veins crosses foramen ovale via septum primum into left side of the heart + around body

29
Q

What happens after ostium secundum formed?

A

septum secundum starts to grow

30
Q

What’s persistent foramen ovale?

A

flap valve doesn’t seal completely
10% of population seen as probe patency
risk factor for stroke + in divers

31
Q

Eg of atrial septal defects?

A

Persistent Foramen Ovale
Ostium primum defect
Ostium secundum defect

32
Q

Define acyantoic defect + eg

A 
L to R shunt so normal levels of oxyhaemoglobin in systemic circulation so no cyanosis
atrial septal defects
ventricular septal defects
atrioventricular septal defect
patent ductus arteriosus
33
Q

Why don’t atrial septal defects cause cyanosis?

A

blood shunting from L -> R atria, but oxygenated blood entering RA then being passed around again

34
Q

How does interventricular septum form?

A

grows from the wall, towards AV cushion, initially as thickened trabeculum

35
Q

eg of Ventricular Septal Defects?

A 
75% perimembranous
25% muscular
Small - small L>R shunt
Medium -moderate L>R shunt
Large - large L>R shunt, surgically repaired in childhood
36
Q

Describe the septation of the outflow tract

A
  • single tube (bulbus + conus) separated into aorta+pul artery
  • must be attached to the L + RV respectively
  • 2 cushions spiral via truncus arteriousus
  • complex remodelling at each end –> great vessels
37
Q

What’s Ductus Arteriosus?

A

allows blood that does enter into the RV to be transferred into the aorta so allows fetal circulation to bypass lungs, closes after birth becoming ligamentum arteriosum

38
Q

What’s patent ductus arteriosis?

A

when ductus arteriosis doesn’t close after birth so aorta blood crosses ductus arteriosis entering pul artery

39
Q

Describe the process of the formation of the outflow tract

A
  • spiralling cushions separate aorta + pul artery
  • neural crest cells contribute to AP septum
  • complex remodelling of aortic arches
  • proximal cushions fuse w IVS + AVS
40
Q

Describe diff types of OFT defects

A
  • result in common truncus
  • associated w neural crest defects (eg 22q11 Deletion Syndrome / DiGeorge Syndrome)
  • unequal division of OFT leads to aortic or pulmonary stenosis
41
Q

Features of transposition of the great arteries (TGA)?

A
  • Aorta to right ventricle
  • Pul trunk to left ventricle
  • Arterial trunks side-by-side
  • caused by abnormal outflow tract cushions
  • lethal w/o VSD, ASD, PDA
  • Cyanotic
42
Q

How do you surgically correct transposition of the great arteries?

A

arterial switch

atrial switch

43
Q

Features of tetralogy of fallot?

A
  • venticular septal defect (large)
  • pul stenosis
  • right ventricular hypertrophy
  • overriding aorta
  • R to L shunt so cyanotic
  • Abnormal looping leads to malalignment of segments
44
Q

Define cyanotic defects + eg

A 
R to L shunt
transposition of the great arteries
tetralogy of fallot
truncus arteriosu
TAPVC(Total anomalous pulmonary venous connection)
45
Q

Why does squatting relieve cyanosis in tetralogy of fallot?

A

increases peripheral arterial resistance, decreasing R to L shunt so increases pul blood flow

46
Q

Why’s there a R to L shunt in tetralogy of fallot?

A

pul stenosis

47
Q

Why’s there right ventricular hypertrophy in tetralogy of fallot?

A

pul trunk more narrow

48
Q

What’s the origin of conduction tissue?

A

come from neural crest cells BUT specialized myocardium

49
Q

What are variations in conduction properties caused by?

A

diff in ion channel+connexin (gap junctions) expression

50
Q

How does the conduction system differentiate?

A

by progressive, localised recruitment from heart tube myocardium

51
Q

What are the diff electrical insulation layers?

A
  • Fibro-fatty layer at AV junction (ex cushions)

- Ventricular bundle branches wrapped in fibrous sheath

CVS II (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions