Cardiovascular Flashcards
Describe the formation of the primitive heart tube
Pre-day 19
- Horseshoe forms
Day 19
- 2x endocardial tubes arise from this
Day 20-21
- these tubes fuse and primitive heart tube forms
Describe what happens in cardiac looping
Begins day 23
Bulbus cordis moves ventrally and caudally, to right
Primitive ventricle moves dorsally and back up
What is the primitive heart comprised of (superior to inferior)
Aortic roots (arterial poles)
Truncus arteriosus
Bulbus cordis
Ventricle
Atrium
Sinus venosus (venous poles)
Describe septation
Superior and inferior endocardial cushions meet at the central AV
Superior continues to divided into left and right atrium
- foramen ovale here
- closes at birth fossa ovale
Inferior continues down the IV septum
- separates into LV/RV
- upper membrane part, lower mucosal part
How many aortic arches are there
6
What do the aortic arches arise from
Branch off truncus arteriosus
27 days - 7 weeks
Continues to form aortic sac
What does the first aortic arch create
(The max)
Maxillary
What doe the second aortic arch create
Hyoid
What does the 3rd aortic arch create
(3rd letter is c)
Common carotid artery
Proximal internal carotid artery
What does the 4th aortic arch create
Right subclavian branches
What does the 5th aortic arch form
NOTHING
Regresses
What does the 6th aortic arch form
Right - pulmonary trunk
Left - ductus arteriosus
How many shunts are there in the foetus
3
Name the three shunts in the foetus
Foramen ovale
Ductus venosus
Ductus arteriosus
What is the role of the foramen ovale
Right to left atrium to bypass the lungs
