Flashcards in Development Of The CVS Deck (34):
What does cephalocaudal folding achieve?
Brings the heart tube into the thoracic region
What are the areas of the primitive heart called? (Top to bottom)
Where does the cephalic portion move?
Ventrally, caudally and right
Where does the caudal portion move?
Dorsally, cranially and left
Which sinus does looping create?
The transverse pericardial sinus
What does lateral folding achieve?
Creates a heart tube
In the sinus venosus, which way does venous return shift and what effect does this have?
Venous return shifts to the right therefore the right sinus horn enlarges and the left sinus horn recedes.
Where does the right atrium come from?
Most of the primitive atrium and the right sinus horn
Where does the left atrium come from?
Small portion of the primitive atrium and absorbs the proximal parts of the pulmonary veins.
How is the oblique sinus formed?
As the left atrium expands and absorbs the pulmonary veins.
What is the role of the ductus arteriosus?
Bypasses the lungs in foetal circulation
Connects the pulmonary trunk to the aorta
How many aortic arches are there in an embryo before remodelling and how are they numbered?
5 pairs of arched arteries
Numbered: 1, 2, 3, 4 and 6
What does the 4th artery arch become?
RHS: proximal part of right subclavian artery
LHS: arch of aorta
What does the 6th artery arch become?
RHS: right pulmonary artery
LHS: left pulmonary artery and ductus arteriosus
What nerve corresponds with the 6th arch?
Recurrent laryngeal nerve
How far down does the recurrent laryngeal nerve descend?
What happens to the left recurrent laryngeal nerve?
It becomes hooked around the shunt between the pulmonary trunk and the aorta (ductus arteriosus)
How does the heart split into left and right channels?
Endocardial cushions develop in the atrioventricular region (dorsal-ventral) and grow towards each other and fuse in the middle.
What are the steps of atrial septation?
1. Septum primum grows down towards cushions
2. Ostium primum is present before the septum fuses
3. Before ostium primum closes, ostium secundum appears in septum primum
4. Septum secundum grows (crescent shaped) and the hole in this is the foramen ovale
What are the 2 components of the ventricular septum?
What do we call the small gap left by the muscular septum before the membranous portion grows?
Primary interventricular foramen
What are the most common heart defects?
Interventricular septum defects (VSD)
What is the name of the septum that divides the outflow tract?
How does the conotruncal septum form?
Endocardial cushions appear in the truncus arteriosus and as they grow towards each other, they twist around each other to form a spiral septum.
Name the adult remnant of the ductus arteriosus
Name the adult remnant of the ductus venosus
Name the adult remnant of the umbilical vein
What happens if the conotruncal septum does not adopt its spiral course?
Transposition of the great vessels
What disorder does lithium cause?
Disorders of the tricuspid valve
Where do progenitor heart cells originate?
Describe the primary heart field
A horseshoe shaped cluster of progenitor heart cells in the splanchnic layer of mesoderm
What does the right laryngeal nerve hook around?
Right subclavian artery
How does coarctation of the aorta present?
Heart failure symptoms
(Lead to LVH)