Cardiovascular Embryology Flashcards
1
Q
WHere do the majority of birth defects?
A
Congenital heart defects
2
Q
What is more anterior, the pulmonary trunk or aorta?
A
the pulmonary trunk
3
Q
Where do cardiac progenitor cells lie?
A
in the epiblast
4
Q
How do cardiac progenitor cells in the epiblast migrate?
A
cranially to caudially through the primitive streak to become splachnic mesoderm
5
Q
angiongenic cell clusters coalesce to form right and left (blank)
A
endocardial tubes
6
Q
How does the embyro fold?
A
cephalocaudally and laterally
7
Q
Endocardia tubes fuse via (blank)
A
programmed cell death
8
Q
What are the four layers of the heart tube?
A
1) endocardium
2) cardiac jelly (thick acellular material made by the myocardium)
3) myocardium
4) epicardium
9
Q
What is a thick acellular material made by the myocardium?
A
cardiac jelly
10
Q
What makes the epicardium of the heart tube?
A
Mesothelium migrates in from septum transversum
11
Q
What does the epicardium of the heart tube form?
A
coronary arteries
12
Q
What will form on either side of the notochord?
A
endocardial tubes
13
Q
Through what type of folding do the 2 endocardial tubes fuse?
A
embryonic folding
14
Q
What are the layers of the heart tube from inside out?
A
endocardium (endothelium)-> subendothelial space (CT space)-> cardiac jelly->myocardium->epicardium
15
Q
What allows the endocardial tube to be flexible?
A
cardiac jelly
16
Q
What is outside the subendothelial space with invagination into subendothial space?
A
Cardiac jelly
17
Q
(blank) veins drain the yolk sac.
A
vitelline
18
Q
(blank) veins carry oxygen from placenta
A
umbilical
19
Q
(blank) veins drain body wall and head.
A
common cardinal
20
Q
The inflow and outflow tracts are connected to the heart tube before any (blank) takes place.
A
cardiac folding
21
Q
What 3 types of veins go to the in flow tract of the heart?
A
umbilical, common cardinal, and vitelline
22
Q
Around (blank) days, a series of expansions, constrictions and folds occur in the cardiac tube which begins the creation of the cardiac loop.
A
23
23
Q
During the formation of the cardiac loop, what four dilations occur in the heart tube?
A
1) sinus venosus
2) primitive atrium
3) primitive ventricle
4) bulbus cordis
24
Q
What day is the cardiac loop complete?
A
28
25
During the formation of the cardiac loop, what remains fixed in place?
arterial and venous ends anatomically
26
What does the distal part of the bulbus turn into?
the truncus arteriosus
27
What does cardiac loop formation create?
normal position of heart chambers and changes a single circuit system into asymmetrical system
28
When does the heart tube start beating?
23 days
29
The development of the heart develops from what direction?
inflow to outflow tract direction?
30
When does the remodeling of the sinous venosus occur?
day 24
31
What happens on day 24 to the sinous venosus?
There is a shift to the right of venous return.
1) right vitelline vein-> IVC
2) right anterior cardinal vein-> SVC
3) left sinus horn-> coronary sinus and oblique vein of the left atrium
4) right sinus horn blends into the right posterior wall of the right atrium becoming the sinus venarum
32
The right vitalline vein turns into what?
IVC
33
What does the right anterior cardinal vein turn into?
SVC
34
What does the left sinus horn turn into?
coronary sinus and oblique vein of left atrium
35
What does the right sinus horn turn into?
sins venarum
36
What all open into the sinus venarum?
IVC, SVC, and coronary sinus
37
the (blank) also contains crista terminalis (conducting fiber tract SA node to AV node)
sinus venarum
38
the pulmonary veins grow into what?
the smooth portion of left atrium
39
Why is it important that the sinus venarum is smooth?
helps with blood flow
40
What are found throughout the heart tube and are made of splachnic mesoderm?
endocardial cushions
41
What are endocardial cushions made out of?
splachnic mesoderm
42
In the coronal truncal area, the splachnic mesoderm gets an infusion of neural crest cells to create what?
endocardial cushions
43
Cardiac jelly creates (blank)
endocardial cushions
44
(blank) play a role in formation of septa and valves
endocardial cushions
45
endocardial cushions play a role in (blank) defects
cardiac
46
How is the partition of the primitive atrium formed?
endocardial cushions
47
Endocardial cushions from above and between the atrium forms what?
the septum primum
48
Is the septum primum thick or thin?
it is a thin membranous septum
49
What makes the septum and valves of the heart?
endocardial cushions
50
The septum primum only allows blood flow in what direction?
right to left
51
The septum primum has holes called (blank) to maintain he right to left shunt.
Ostium secundum
52
What is a thick muscular septum that forms to the right of the septum primum?
septum secundum
53
(blank) forms in septum secundum maintaining the right to left shunt/
foramen ovale
54
What forms ostium secundum?
programmed cell death
55
(blank) closes immediately after birth.
foramen ovale
56
HOw does the foramen ovale close after birth?
| FUNCTIONAL CLOSURE
the pressure drop in right atrium due to absence of placental circulation and increase in left atrial pressure due to increases pulmonary venous return.
57
When is the anatomically closure?
3 months when the septum primum and septum secundum fuse
58
What is probe patency of the formane ovale? How often is it present? Is it of clinical importance?
When you have incomplete anatomical fusion of septum primum and septum secundum.
25%
No
59
The opening of the septum secundum is in the inferior or superior part of the atrium?
inferior
60
In the septum primum the openin is in the superior part of the atrium?
superior part
61
What kind of fusion make the septum primum and septum segunda fuse together?
fibrous
62
What kinds of things can go wrong during atrial partioning?
Atrial septal defects and cor triloculare biventriculare
63
What atrial septal defects is most clinically significant and are males or females more susceptible to them?
ostium secundum defects are most clinically significant. Females get them more
64
What is the absence of the interatrial septum.
cor triloculare biventriculare
65
Endocardial cushions play a role in which heart defects?
ASD, VSD, transposition of great vessels, tetralogy of fallot
66
Conotruncal cushions play a role in defects, what kind are they?
craniofacial defects and heart (include neural crest cells) i.e. if you find a face defect look and make sure not a heart defect too
67
How many endocardial cushions form the partitioning of the atrioventricular canal?
what do they form exactly?
four
forms septum
forms bicuspid and tricuspid valves
68
What are things that can go wrong with the partitioning of the atrioventricular canal?
persistent common atrioventricular canal and abnormal division of the canal
69
Partitioning of the truncus arteriosus and the bulbus cordis involves what type of swellings/ridges?
truncal and conal swellings
70
The truncal and conal swellings form (blank) septa dividing truncus arteriosus and bulbus cordis into aortic and pulmonary channels.
aorticopulmonary
71
Neural crest contributes to both the truncal and conal swellings to form CT and smooth muscle of the (blank). What do the neural crest cells migrate down through?
aorticopulmonary septum
| pharengeal arches
72
How is the partitioning of the truncus arteriosus and the bulbus cordis done?
through spiraling, which lines up the correct outflow tract with the correct ventricle.
73
What happens if you remove neural crest cells / or block their migration to the truncus arteriosus?
No partitioning which leads to persistant truncus arteriosis
74
What is this:
- no formation of the AP septum
- a single arteriole vessel leaves the heart giving rise
to the aorta and pulmonary trunks
- usually accompanied by a defect in the interventricular septa
- clinically marked cyanosis
- can cause pulmonary hypertension (overloading of lungs)
persistent truncus arteriosus
75
What is this?
- occurs in about 5 out of every 10,000 births
- failure of outflow tract openings to ALIGN with ventricles
- clinically marked cyanosis
tetralogy of fallot
76
What are the four components of tetralogy of fallot?
ventricular septal defect (primary cause)
pulmonary stenosis
overriding aorta
thickening of right ventricle
77
What is this:
- failure of the aorticopulmonary septa to develop in a spiral fashion
- aorta/right ventricle; pulmonary trunk/left ventricle
- clinically marked cyanosis
- infants that survive after birth due to patent ductus arteriosus and/or ASD or VSD that allows intermixing of blood.
- complete TGA is incompatible with life if there is no associated septal defects or patent ductus arteriosus.
transposition of the great vessels
78
When is the primitive ventricle partitioned?
end of 4th week
79
Where does the muscular interventricular septum develop?
midline on the floor of primitive ventricle
80
what is between the free edge of muscular septum and aventricular cushion?
the Interventricular foramen
81
What makes up the membranous IV septum (the baby portion of the septum)?
1. right and left bulbar ridges
| 2. inferior AV cushions
82
Ventricular septum defects are the most common cardiac congenital defect (30% of children with congenital heart disease). What are the two ways to create VSD?
1. Failure of membranous IV
septum to form – most common
2. Muscular VSD- single or multiple
perforations in the muscular IV
septum
83
In a neonate:
A left to right shunt will be cyanotic or acyanotic?
A right to left shunt will be cyanotic or acyanotic?
acyanotic
| cyanotic
84
WHen are the outflow tracts remodeled?
day 50 (way after inflow tracts)
85
(blank) gives rise to the liver sinusoids (including the ductus venousus) , the portal system (portal vein, SMV, IMV) and a portion of the IVC
The vitelline system
86
What allows the fetal blood to bypass the liver?
ductus venousus
87
The right umbilical vein disappears and the left umbilical vein anastomoses with the (blank).
ductus venous
88
Which umbilical vein disappears?
the right
89
Oxygenated blood from the placenta reaches the heart via the (blank)
single left umbilical vein and the ductus venosus.
90
What is the passage of oxygen from the placenta?
left umbilical vein, ductus venosus, inferior vena cave
91
What makes the ductus arteriosus?
arch 6
92
Where is arch 6?
on the left side
93
What makes the pulmonary vessels and the ductus arteriosus?
arch 6
94
In a neonate, patent ductus arteriosus will reverse the blood flow of and result in what?
pulmonary hypertension
95
Ductus arteriosus usually closes within how many days?
1-2 days
96
What can forcefully close PDA?
prostaglandin inhibitors
97
well oxygenated blood returns from placenta via the (blank)
umbilical vein
98
About half of the blood passes through the hepatic sinusoids/ the other half bypasses through the liver and goes through the ductus venosus into the (blank)
IVC
99
Blood goes into the right atrium/most blood goes through the foramen ovale into the left atrium acting as a (blank), which is opposite of a neonate.
Right to left shunt
100
Fetal circulation -Blood into the left ventricle and out the ascending aorta gives the best oxygenation to (blank)
head neck and upper limbs
101
A small amount of blood in fetal circulation enters the (blank) where a small amount go into the lungs but the majority passes through the ductus arteriosus into the aorta creating a (blank) shunt
pulmonary trunk
| right to left shunt
102
(blank) arteries return blood to the placenta for re-oxygenation.
umbilical
103
Parititioning of ventrical, endocardial cushion creats a (blank) septum that goes 90% of the way up to the atrium. The last 10% of the way is filled with a (blank) septum (comes from endocardial cushions from AV ledge as well as growing down of the AP septum).
muscualr ventricular septum
| membraneous ventricular septum
104
What are the most common cardiac congential defects? What is the most common cause of this cardiac congential defect?
ventricular septal defects
| Membraneous ventricular septum
105
What happens when you have transposition of great vessels? What can relieve this?
You get deoxygenated blood to your systemic circulation and oxygenated blood to your lungs.
A right to left shunt or surgery
106
What forms the tricuspid and bicuspid valves?
AV canal ( also forms septum between atria and ventrices)
107
Squatting is an indication of what?
tetrology of fallot
108
NEONATES: anomalies of aortic arches (right arch, double arch, retro-esophageal right subclavian artery) and coarcationof aorta is what?
no shunt cardiac abnormality (acyanotic)
109
Is having no shunt in neonate cyanotic or acyanotic?
acyanotic
110
NEONATES: Having persistant ductus arteriosus, interatrial septal defects, interventricular septal defects are what kind of shunt and will is make you cyanotic or acyanotic?
left to right (acyanotic)
111
NEONATES: Having complete transpositions of great vessels, truncus arteriosus communis and teratology is what kind of shunt and is it cyanotic?
right to left shunt (cyanotic)
112
Heart usually develops from (blank) tract to (blank) tract
inflow to outflow
113
Above the (blank) remodeling begins with shift to the right of the venous return for the inflow tract.
above the diaphragm
114
During the remodeling of the inflow tract, the right vitelline veins turns into?
IVC
115
During the remodeling of the inflow tract, the right anterior cardinal vein turns into?
SVC
116
During the remodeling of the inflow tract, the left sinus horn turns into what?
coronary sinus and oblique vein of left atrium
117
During the remodeling of the inflow tract, the right sinus horn blends into what?
right atrium to create sinus venarum
118
The IVC, SVC, and coronary sinus all open in the (blank)
sinus venarum
119
the sinus venarum contains the (blank)
crista terminalis (conducting fiber rtact SA node to AV node_
120
What contains the conducting fiber tract from SA node to AV node
crista terminalis
121
What does the smooth portion in the left atrium turn into?
pulmonary veins
122
Below the diaphragm, the (blank) system gives rise to the liver sinusoids, the portal system,and a portion of the IVC.
vitelline system
123
Below the diaphragm the (blank) disappears and the left umbilical vein anastomoses with the ductus venous.
right umbilical vein
124
Oxygenated blood from the placenta reaches the heart via the (blank)
single left umbilical vein and ductus venosus
125
What happens below the diaphragm?
Vitelline system creates portal system, liver sinusoids and portion of IVC
Right umbilial vein disappears and left umbilical vein anastomoses with ductus venous
126
WHat does ductus venosus do?
allows oxygenated blood to bypass the liver
127
The outfow tract in fetal development occurs ventrally with the (blank) and expansion of cranial end of (blank)
aortic arch arteries arise from the aortic sac
| truncus arteriosus
128
The outlfow tract in fetal development also occurs dorsally, what happens dorsally?
aortic arches connect to the left and right of dorsal aortae
129
What will arch 3 of the aorta create?
carotid arteries
130
how many pairs of aortic arches are there?
6
131
Which arches does the adult arterial system develop from?
3,4 and 6 and R and L dorsal aortae
132
Arches 3,4 and 6 develop asymmetrically and make major (blank)
contributions
133
WHen you have a baby in utero you think what kinds of shunts?
neonates?
typically right to left ( formamen ovale, ductus arteriosus)
| typically left to right (" ")
134
What makes up the umbilical cord?
2 arteries 1 vein surrounded by whartons jelly
135
Describe fetal circulation:
umbilical cord oxygenated blood-> passes up through umbilical vein-> through ductus venosum-> IVC-> sinus venerum->foramen ovale + escaped blood form right ventricle jumps through ductus arteriosus -> aorta-> umbilical arteries return blood for reoxygenation
136
When can yo hear a heart beat in utero with transvaginal ultrasound?
day 25
137
Describe what happens to the heart at birth:
Birth-> open blood flow to liver, shut off shunts,, slam membranous septum against muscular in atria to shut off formane ovale.
138
at birht the 3 shunts that permitted most o the blood to bypass the liver (blank)
cease to function
139
As soon as the baby is born, the (blank) are no longer needed.
umbilical vessels, ductus arteriosus, formane ovale
140
(blank) provides a dramatic fall in vascular resistance.
aeration of the lungs
141
WHen you are born, what happens to your blood flow in terms of pressure and flow.
1) Aeration of lungs: increase in pulmonary blood flow-> increase left atrial pressure above (higher than right atrium), closing of foramen ovale,
2) constriction of ductus arteriosus
3) constriction of ductus venosus
142
```
What are the fetal remnants:
Umbilical arteries turn into?
Umbilica vein turn into?
ductus venosus turns into?
ductus arteriosus turns into?
formen ovale does what?
```
1) internal iliac arteries and medial umbilical
2) ligamentum teres of liver
3) ligamentum venosum
4) ligamentum arteriosum
5) becomes obliterated
143
Does patent ductus arteriosus happen more often in females or males? What can close a PDA?
females
| prostaglandin inhibitors
