Heart dev Flashcards
5 types of mesoderm
- cardiogenic
- Paraaxial
- Nephrogenic
- Lateral plate
- Notochoral
Type of mesoderm that is most cranial
cardiogenic - heart
point where R and L heart fields meet
cardiac crescent
tissue source of aorta
splancheopleuric mesoderm
3 keys steps in heart formation
- pre-looping - formation of chambers
- looping - linear tube loops and fold on itself - to RIGHT
- post-looping - dev of detailed structures in heart
4 primitive chambers and their products (caudal to cranial)
- primitive atrium - L and R atria
- Prim ventricle - LV
- bulbis cordis - RV
- truncus - main outflow - aorta and pulm trunck
4 products of dextro looping
- apex on left
- RV rotates ant.
- perfect spacial geometry
- Veinous pole brought cranial
2 adv of looping
- stronger beat
2. geometry alignment
heart on R and whole body on right
dextrocardia - levo-looping
situs inversus totalis
source of main portion of atria
veins themselves (sinuses)
source of atrial appendages and sinuses
app - primitive artria
sinuses - veines
beginning point of atrial wall
septum primum
second adjacent wall of atria
septum secundum
2 holes in original atrial wall
osium primum and secundum
Formation of AV valves
Common AV orifice separated in 2 by endocardial cushions
What happens when AV process goes wrong
AV septal deficits (AVSD)
3 components of IV septum
- Thick wall of muscle from vent. floor
- endocardial cushions
- single outflow artery (truncus)
failure of truncal septation
persistent truncus arteriosus
two divisions of truncus
aorta and pulm trunck
time when heart appears and functions
appears - 3rd week function 4th
what begins to separate AV
endocardial cushions
location of ostium primum and secundom
septum primum
side on which septum secundum appears
R side
what septum primum becomes
valve of foramen ovale
where IV septum starts
floor of ventricles
effect of placental occlusion
fall in pressure to R atrium
effect of pulm bloodflow
incr. L atrium pressure
define transpostition
PT and aorta backwards
cause of patent ductus arteriosus
abnormal neural crest cell formation
