Heart tube, Atrial and Ventricular septation Flashcards
- early development is at —
- cardiac loops are : — , — , — , —
- we will have:
1- seperation of —
2-Septation of — and — arteriosus
3- Formation of the — and large — tracts
4- Septation of the —
heart tube
loops:
Atrial primordium
Atrio-ventricular canal
Ventricular primordium
Outflow tract (conus and truncus arteriosus)
venctricles
conus and truncus
artira
large inflow tract
artira
heart tube:
- blood islands surronded by —
- Begins in the — week when — via – no longer possible
-Cardiogenic field formed by —
-Progenitor located in the — — to the —
-Migration through the – and positioning– to the buccopharyngeal membrane
-In the late presomite stage induction by — to differentiate into —
-Eventually: — islands merge and form a — shaped — tube lined by — and surrounded by —
-Other islands located on either side of the — form the —
myoblast
3rd week
nutrition
diffusion
cardiac progenitor cells
located in epiblast lateral
primitive steak
steak
rostal
endometrm
myoblast
angioblastic island
horse hsoe shaped ventricle tube
endothelium
myoblast
midline
dorsal aoerta
(check slide 8 so importanrt )
heart tube:
- Fusion of – , — filled tubes into — –> completed by the end of the — week
Myocardial contraction starts at about — (beginning of the — week)
-Slight afterwards, during the – week, — -driven blood flow starts
2 blood filled tubes into one
third week
22 days
4th week
4th qeek
heartbeat driven
(check slide 10-13 so important )
check from slide 15 - 24
sooo important
Initial septation starts during the — week
Cranial growth of the interventricular ridge (IVR)
5th
septation of conus and truncus arterious:
1- Truncus cushions (swellings):
Right —
Left —
2- Cushions Twist around each other:
Extend — into —
3- Fuse to form —- septum :
— & — channels , – from left & right ventricles
superior
inferior
proximally
conus
aorticopulmonary septum
arotic and pulmonary channels
outflow
Two fundamental events are associated with the septation of conus and truncus:
1- — of the — foramen
2- formation of the —
closure of the interventricular formen
semilunary valves
septation of conus and truncus arteirous:
- The interventricular foramen closes by the —
caudal growth of the —
fusion with — part of the interventricular septum (1)
formation of— part of the interventricular septum (closes the IVF)
7th week
conal septum (CS)
musuclar
membrenous
chck slide 37 ,39,40,41
atria from inside:
- Entrance of sinus venosus has shifted over to —
- Atrium — in size
- Some of the new wall is formed from the —
- — wall of right atrium !!
1- Right venous valve:
- —
- Valve of —
- Valve of —
2- Left venous valve
Small part of —
right
enlarges
sinus venosus
smooth wall
crista terminalis
ivc
coronary sinus
artrial septum
artria from inside:
1- Now no — inflow
Bud / outgrowth develops:
- Grows —
- —- !!
- Divides / grows & connects with developing — buds
2- Atrium enlarges in size
- Some of the new wall is formed from these —
- – walled part of atrium
- Typically — veins
venous
posteriolry
pulmonary vein
lung
pulmonary veins
smooth
4 pulmonary veins
( check slide 49 )
septation of the artria:
- Growth of —
-Formation of — during —
-Foramen secundum in — at —
-Growth of septum secundum — of septum primum
- — of foramen primum and persistence of foramen secundum at –
septum primum
foramen primum
5th week
septum primum
5th week
right
closure
6th week
closure of foramen ovale:
1- Pre-natal circulation:
Lungs —
— Pulmonary Vascular Resistance (PVR) &— pressures
Blood flows from — to —
2-Post-natal changes in circulation lead to Closure of the —
Lungs —
PVR — –> RV pressure —
Pressures now — > —
Complete fusion in —
defleated
high
artrieal
right to left
Foramen Ovale
inflate
drops
drops
LA > RA
1 year
artrial septal defects:
1- Foramen Primum defect
- Septum primum fails to close —
- Part of AV canal defects: Just – AV valves
- Risk of associated — defects
2- Foramen Secundum defect
— common defect (— % of ASDs)
- Occur in region of — –> —
- Septum primum & secondum fail to –
-Two main causes:
Excessive — of septum primum
Underdevelopment or absence of —
formaen primum
above
valve
most
70%
fossa ovalis –> patent formaen ovale
fuse
resoprtion
septum secundum
artrial septal defects:
- Left-to-right shunting of blood
- — heart disease
- May be —
- — intolerance in older children/adults
Auscultation:
- ejection — murmur
- Perhaps split —
acynotic
asymptomatic
excersise
systolic
S II
check lside 59
presistant trunus aeterious:
-Bulbo truncal ridges fail to — ((0.8/10,000 births)
- No — septum
- — outflow tract remains
- Cyanosis, — murmur
- ALWAYS associated with a —
-Membranous portion of septum fails to develop —
fuse
single
systolic
VSD
superiolry
tetralogy of fallot:
- 9.6/10,000 births
- — division of — region(anterior displacement of conotruncal septum)
- Pulmonary stenosis: — – ventricular outflow
- — VSD
- Overriding –
- From directly above the —
- — of the right ventricle
- Right to left shunt aka —
- — thrill
- — murmur: Pulmonary & left sternal border
-Patients characteristically squat to improve symptoms
-Chest X-ray:
May see a “— -shaped” heart
unequa;
conotrucal
narrow right ventricular
large
aorta
septal defecrs
hypertrophy
Cyanosis
palpabl
systolic
boot shaped
transpotion of great vessels:
-4.8/10,000 births- usually accompanied by a – sometimes a—
- Conotruncal septum fails to — –> runs straight –
- Not compatible with life unless another — is present
- Cyanosis, usually — murmur
PDA
VSD
spiral
down
shunt
systolic
important:
End of the fourth week: — loop + Growth of –
S-shaped
right atrium
