Heart Flashcards
(156 cards)
1
Q
what is skeletal muscle formed from
A
periaxial mesoderm
2
Q
what is cardio and smooth muscle formed from
A
visceral lateral plate mesoderm
3
Q
When does the cardiovascular system form?
A
mid 3rd week
4
Q
What does CPC stand for?
A
cardiac progenitor cells
5
Q
Why does the cardiovascular system form in the third week?
A
the trophoblast cannot satisfy the blastocyst’s nutritional rqeuirements by diffusion only
6
Q
What layer are CPC cells located?
A
epliblast
7
Q
What does the intraembryonic cavity (ceoleum) do?
A
separates the visceral and parietal lateral plate mesoderm
8
Q
what forms within the visceral lateral plate mesoderm?
A
blood islands
9
Q
What are the two heart fields?
A
primary and secondary heart fields
10
Q
What are the only structure of head and neck that migrate down?
A
neural crest cells
11
Q
CPC are induced by ____ to form ____ and _____
A
endoderm
myoblasts, hemangioblasts
12
Q
What form the blood islands?
A
Hemangioblasts
13
Q
Where are blood islands formed?
A
primary and secondary heart fields
14
Q
what do blood islands form? (two things)
A
numerous primitive blood vessels (endothelial lined tubes) & blood stem cells
15
Q
What do the numerous endothelial lined tubes unite and form?
A
right & left larger endothelial-lined tubes
16
Q
Myoblasts from VLPM attach to what tubes?
A
endothelial lined tubes
17
Q
ASD appears in what location of atrial septum?*
A
center of atrial septum
18
Q
the primary and secondary cardiac field fuse together and form what?
A
a single aorta & 1 pericardial cavity
19
Q
What does cardiac jelly form?
A
cardiac mesenchyme
20
Q
What does cardiac mesenchyme form?
A
atrial and ventricular septation
21
Q
What moves the primitive heart from dorsal to ventral position?
A
head fold
22
Q
The head fold pushes the primitive heart in what direction
A
from dorsal to ventral
23
Q
The truncus arteriosus will eventually become what?
A
aorta & pulmonary trunk
24
Q
The sinus venousus will eventually become what?
A
atria
25
Lateral folding fuses what 2 things together?
2 large endoethelial lined heart tubes
| 2 dorsal aorta
26
The endothelial lined heart tubes are fused everywhere except:
truncus arteriosus
27
Initially the heart is connected dorsally to the pericardial cavity by what?
dorsal mesocardium
28
What happens as the heart bulges into the pericardial cavity?
the attachment to the dorsal mesocardium rips away
29
when the heart rips away from dorsal mesocardium what does it form?
transverse pericardial sinus
30
After the transverse pericardial sinus is formed, what end is heart tube suspended from?
rostral end
31
what is the rostral end of the heart called (in the beginning, right after transverse pericardial sinus is formed)?
truncus arteriosus (atrial end)
32
What is the caudal end of the heart called (in the beginning, right after transverse pericardial sinus is formed)?
sinus venosus (venous end)
33
How is the heart suspended at the caudal end (as the heart is elongating into the pericardial cavity)?
by septum transversum - the venous end goes into it
34
What is the cardiac jelly involved in forming?
heart septas/walls and connective tissue skeleton of heart
35
What is located b/w the inner endothelial tube & outer myocardium?
cardiac jelly
36
What two things does epicardium form?
most of visceral pericardium & coronary arteries
37
What makes up the myoepicardial mantle?
epicardium and the myocardium
38
What does endocardium form?
endothelial heart tube (progenitor heart cells)
39
What does myocardium form?
progenitor heart cells + surrounding visceral lateral plate mesoderm
40
what does epicardium form?
visceral pericardium
| coronary arteries - endothelium & smooth muscles
41
what does cardiac jelly form?
cardiac mesenchyme
| CT skeleton of heart
42
What forms the primitive right ventricle?
bulbus cordis
43
What forms the mid part of bulbus cordis & outflow tracks of both ventricles?
conus cordis
44
What forms the distal part of bulbus corids & proximal aorta & pulmonary trunk?
truncus arteriosus
45
What forms b/w the conus cordis & tuncus arteriosus to separate them into aorta & pulmonary trunk?
endocardial cushions form conotruncal/bulbar ridge with conotruncal septum (neural crest) (pg 10)
46
What will the aortic sac form?
distal aorta
47
The growth of bulbus cordis is controlled by what?
neural crest cells
48
What day does the heart tube begin to bend? (and week)
day 23 ,week 4
49
What direction does the heart tube fold?
counter clockwise
50
What causes the heart to fold counterclockwise?
the bulbus cordis and primitive left ventricle grow faster than other parts of tube
51
What is the name of the congenital defect where heart apex is located on right side of body due to improper rotation (clockwise) of the heart tube?
Dextrocardia
52
Describe Dextrocardia
Rotates CW instead of CCW
congenital defect where heart apex is located on right side of body due to improper rotation (clockwise) of the heart tube
53
What is Dextrocardia of embryonic arrest?
heart is shifted slightly more to right than normal
54
What is Dextrocardia situs invertus?
heart is a mirror image of normal heart but on right side
55
What is dextrocardia situs invertus totalis?
the viscera is reversed, but is it rarely perfectly reversed so usually associated with congenital heart defects
56
What forces the atria superiorly?
cardiac looping
57
the atrioventricular canal allows blood to flow from where to where?
sinus venousus to truncus arteriosus
58
What causes partitioning of the AV canal?
cardiac jelly
59
What week does the AV canal get partitioned, forming primtiive atrium and ventricle?
mid4th to end of 5th
60
by the end of the 4th week, what form the endothelial cells of heart that are transformed into mesenchymal cells?
dorsal & ventral endocardial cushions
61
What do the dorsal and ventral endocardial cushions do as they grow?
they merge together
62
what forms when the endocardial cushions merge together as they grow?
form septum intermedium w/ right & left atrioventricular canals
63
As the heart grows and there is more cardiac looping, describe the affect on the AV canal
heart wall size is increased, septum intermedium & AV canals shift left
64
If the septum intermedium doesn't form, what happens?
the heart won't form
65
What is septum intermedium made of?
VLPM
66
What forms the AV valves?
dense mesenchyme which comes from cardiac jelly
67
What happens to common atria at end of 4th week?
it divides into 2
68
What divides the atrium into 2 but leaves an opening?
septum primum
69
What is the opening that is left by the septum primum when it makes atrium called?
foramen primum
70
what is the foramen primum?
a shunt to bipass lungs, allows blood to go b/w left and right atria
71
what will happen to upper part of septum primum?
it will disappear
72
what is the name of the second membrane that grows down to the right of septum primum?
septum secundum
73
what will septum primum eventually fuse with and form?
fuses with endocardial cushions and form septum intermedium
74
as the septum primum fuses with endocardial cushions, what else happens that allow continuous flow of oxygenated blood to left and right atrium?
openings develop in central part of septum primium - they are called foramen secundum
75
What is the name of the second muscular membrane to the right of the septum primum?
septum secondum
76
pressure after birth causes fusion of what with what?
septum primum with septum secundum
77
the septum secundum creates what fossa and how?
fossa ovale - creates it when the lower segment of secundum receeds
78
The "upper limb" and "lower limb" are part of what?
septum secundum
79
How does septum secundum form?
grows down from septum premum and up from septum intermedium
80
How does lower limb form? (heart)
incorporation of sinus horns into right atrium
81
When openings develop in the central part of septum primium it allows what?
continuous flow of oxygenated blood to left atrium
82
where does blood flow in right left shunt?
from right atrium to left atrium
83
what must always be preserved until the atrial wall is fully formed?
right-left shunt
84
What does ASD stand for?
atrial septal defect
85
What is the most common type of ASD?
Ostium secundum atrial septal defect
86
What causes Ostium secundum atrial septal defect?
Excessive reabsorption of septum primum
or
incomplete development of septum secundum
87
What is the result of Ostium secundum ASD?
left to right shunt mixing of oxygenated & deoxygenated blood in center of atrial septum
88
What causes Ostium primum ASD?
Non-fusion of septum primum with septum intermedium
89
What is the result of ostium primum ASD?
lower portion of atrial septum: left to right shunt mixing of oxygenated & deoxygenated blood
tricuspid valve cleft
90
what is a tricuspid valve cleft
elongated hole in anterior leaflet
91
What causes patent foramen ovale (PFO)?
Smaller than Ostium secundum ASD
| -Foramen ovale doesn’t seal at limbus
92
What is the result of PFO?
Left → Right shunt mixing of oxygenated and deoxygenated blood
93
Can PFO fix itself?
if it is small it may fix itself, if it larger might need surgery
94
What causes hypoplastic left heart syndrome?
-Premature closure of foramen ovale
95
What is the result of hypoplastic left heart syndrome?
Prevents blood from reaching left heart so its underdeveloped and right heart is enlarged
Incompatible with post natal life
96
During the process to have atrial openings, what happens on the venous ends initially?
sinus venosus open into middle of primitive right atria
| right and left horn of equal size
97
What 3 veins go off of the equally sized right and left horn off of the sinus venosus?
umbilical vein
vitelline vein
common cardinal vein (and anterior and posterior)
98
What does the umbilical vein do when it comes off of the left and right sinus venous horn?
carries oxygenated blood from palcenta
99
What does the vitelline vein do when it comes off the left and right sinus venous horn?
drains yolk sac
100
What does the common cardinal vein do when it comes off of the left and right sinus venous horn?
anterior cardinal vein drains head and neck
| posterior cardinal vein drains trunk
101
As time passes what happens to the two horns (that come off of sinus venous) regarding their size?
right horn increases in size
| left horn decreases, parts of it will merge with right
102
The sinoatrial orifice moves and opens into what?
it opens into what will become the right atrium
103
What will the anterior cardinal vein become?
SVC
104
What will the posterior cardinal vein become?
IVC
105
What part of the heart gives rise to the anterior rough part?
right half → primitive atrium
106
the sinuatrial orifice from right horn opens into what?
right atrium
107
how is the sinus verarum formed?
right valve of right horn & septum intermedium smoothing over most of right atria
108
How is the right atria divided internally and externally?
crista terminalis internally
| terminal sulcus externally
109
The rough part of atria is made of what?
pectinate muscles
110
Absorption of the right horn of the sinus venosus gives rise to what?
the posterior smooth part or sinus venarum part and right half of the Atrioventricular canal (A-V canal)
111
Besides absorption of the right horn of sinus venosus, what else gives rise to AV canal
endocardial cushions
112
Inferior part of the right sinuatrial valve forms what?
the valves of IVC and coronary sinus
113
What forms the rough part of left atria?
trabeculated auricle
114
Primordial pulmonary veins are an outgrowth of what?
dorsal left atrial wall (just left to septum primum)
115
primordial pulmonary veins will eventually develop a connection with what?
developing lung buds
116
As the left atrium grows what veins are incorporated into it?
pulmonary veins
117
Is most of the left atria smooth or rough and why?
smooth - incorporation of primordial pulmonary vein into enlarging left atrial wall
118
The left half of the AV canal is mainly from what?
endocardial cushions
119
What will form the adult muscular part of IV septum?
primordial interventricular septum
120
Initial growth of the primitive ventricle partition is due to what?
enlargement of the ventricular walls
121
further enlargement of the primitive ventricle partition is due to what?
myoblast activity in the septum
122
What is another name for ventricular septum?
Primitive ventricle partition
123
What are the two parts of the ventricular septal wall?
muscular & membranous part
124
When does the interventricular close by?
week 7
125
what closes the interventricular foramen at week 7?
membranous IV septum
126
portions of ventricular wall break up to make what 3 things
trabeculae carnea, papillary muscles and chordae tendinae
127
left umbilical vein forms what
round ligament of liver
128
what allows blood to bipass the liver
ductus venosus shunt
129
what does ductus venosus shunt carry
blood
130
right and left recurrent larngeal nerve come off of what two totally different areas
right: proximal part of sublavian artery
left:
131
what makes up majority of foramen ovale?
septum primium & septum segundum
132
Describe lymph in developing embryo
see pg 52-55 in cardiovascular power point
133
do supracardinal veins form the right sublavian artery?
no
134
what do supracardinal veins form?
azygous & hemiazygous
135
Does ligmentum arteriosum shunt blood?
no
136
after birth what happens to ductus arteriosum
becomes ligmentum arteriosum
137
what happens to the third and fourth arotic arch
they stick around
138
what happens to first and second and fifth aortic arch
they disappear
139
what forms descending aorta
dorsal aorta
140
The hepatic sinusoids that can be observed histologically in an adult liver are derived from which veins
vitelline veins
141
How soon should the ductus arteriosus close after birth?
1-2 hours
142
What is the coronary sinus derived from?
the sinus venosus.
143
What is the smooth part of the right ventricle called
conus arteriosus
144
What is the conus arteriosus (smooth part of right ventricle) derived from?
bulbus cordis
145
What is the proximal part of the aorta derived from
truncus arteriosus
146
What is the trabeculated part of the right ventricle
| derived from?
primitive ventricle
147
Muscular VSD is caused by perforations in what septa
muscular interventricular septum.
148
What are the four things that characterize the tetraology of fallot?
1. Pulmonary stenosis- narrow right ventricular region
2. Interventricular septal defect
3. Overriding of the Aorta
4. Right ventricular hypertrophy
149
A partial development of the AP septum results in what?
Persistent truncus arteriosus
150
What clinical correlation is it if the conotruncal septum is missing?
persistent truncus arteriosus
151
misalignment of bulboconal and ventricular septa and underdeveloped endocardial cushions is what pathology?
membranous ventricular septal defect
152
The proximal part of the internal carotid artery is derived from which aortic arch?
3
153
The proximal part of the right subclavian artery is derived from what aortic arch?
4
154
portal vein is derived from what vein?
right vitelline vein
155
Superior mesenteric vein is derived from what?
vitelline veins
156
What are the renal veins derived from?
subcardinal veins
