Heart Development Flashcards
what type of embryonic tissue is used for vasculogenesis
bv are made from mesenchyme
hemangioblast differentiate into
hematopoietic progenitor cells and endothelial precursor cells
embryonic hematopoietic cells reside in where at day 23? generate what?
liver primordia
embryonic erythrocytes, macrophages, megakaryocytes
definitive hematopoietic stem cells are programmed from? Once signaled they mature into?
hemogenic endothelial cells of dorsal aorta in aortic-gonadal-mesoephric region
myeloid an lymphoid stem cells (for lymph organs and bone marrow)
other than the agm region, is bv formation coupled with hematopoiesis?
NO
what are endothelial precursor cells differentiate from
intraembryonic splanchnic mesoderm
paraxial mesoderm
long tubes (angioplastic plexus) grows by
cont proliferation of endothelial precursor cells
angiogenesis (bud/sprout of new vessels from existing)
intussusception (splitting)
recruitment of new mesodermal cells
excessive growth of a small capillary network
capillary hemangioma
excessive growth of venous sinuses
cavernous hemangioma
angiomas
abnormal bv/ lymphatic growth via vasculogenic process
first heart field
cardiac crescent
epc clusters in horseshoe shape in cardiogenic area of intraembryonic splanchnic mesoderm
during folding, epc differentiate into what
(median growth) endothelial cells forming 2 primitive endocardial tubes
then (lateral folds) brings /fuses tubes together
dorsal aorta is dragged ventrally during folding forming
first aortic arch
inflow to primitive heart?
common cardinal veins (venous blood from head and trunk) vitelline veins (venous blood from gut) umbilical veins (O2 blood from mom)
primary heart tube wall consists of?
endocardium, cardiac jelly, myocardium
first rhythmic contraction, blood starts flowing?
day 22, day 24
sinus venosus is made of?
confluent right and left sinus horns
flow of how blood enters and exits primodia heart
sinus venosus -> primitive atrium -> atrioventricular region ->primitive ventricle -> outflow tract (bulbus cordis) -> aortic sac or root
what delineates early LV (primitive ventricle) from future right ventricle
constriction called inter-ventricular sulcus
what is an aortic sac or root
common confluens of pharyngeal arch bv
contributes to future aorta, pulm a, carotids etc
what suspends the heart tube? what happens to it in the adult?
dorsal mesocardium
ruptures to form transverse sinus
remnants form proepicardial organ
proepicardial organ forms?
epicardium (future visceral pericardium)
the cells migrate over myocardium
in cardiac looping, initial outflow tract becomes?
right ventricle
in cardiac looping, addition of myocardium at the cranial end forms?
conus arteriosus (prox outflow tract) truncus arteriosus (distal outflow tract) later becomes aorta/pulm a
what helps lengthen cardiac tube in cardiac looping?
second heart field
splanchnic mesoderm proliferation
what maintains cardiogenic mesoderm proliferation and proper myocardial cell specification w/in 2nd heart field?
NCC
dictates ncc, PA mesoderm, PA endoderm
What happens to the sinus venosus opening?
shifts to right atrium due to cl, differentiate growth, changes in hemodynamics
asymmetrical expansion of the l sinus horn = net shift of amt of blood returning to the right side
left sinus horn becomes the?
coronary sinus
R common cardinal vein becomes the?
superior vena cava
R vitelline vein becomes the?
inferior vena cava
R inferior valvular fold becomes the?
valve of inferior vena cava
crista termnalis is?
jct between pectinate part of RA and sinus venarum
part R sinus horn and R common cardinal v become?
SA node
what makes the m interventricular septum and m atrial septum?
differential growth
what forms new fibrous CT in AV region and conotruncal ridges of outflow tract?
endocardial cushion tissue from mesenchymal cells
cushion cells are important for what?
fibrous septa formation, mesenchymal for anchoring heart valves and cardiac skeleton
what makes conotruncial ridges?
ECT and NCC
conus arteriosus contributes too?
pulm a and aorta to go out diff V
fibrous portion of interventricular septum
what helps truncus arteriosus divide into pulm a and aorta?
aorticopulmonary septum
septum primum is made from?
dorsal mesenchymal protrusion or spina vestibuli (mesodermal projection from caudal dorsal mesocardium)
makes a hole near AV septum called ostium primum
as cushion tissue close ostium primum, a new hole forms rostrally called?
ostium (foramen) secundum
what overlaps ostium secundum? leaving what foramen?
septum secundum - much thicker to prevent back flow (L to right) only r to l
foramen ovale
blood from IVC in fetal cardiac blood flow goes into?
through foramen ovale into LA -> LV -> arteries
blood from where goes through RA and RV in fetal cardiac blood flow goes into?
how does it get to systematic arterial side?
SVC/coronary sinus, and part IVC
ductus arteriosus
interventricular septum is made of?
m part from ventricular wall and fibrous part from cushion tissue and proximal conotruncal ridges
in partitioning outflow tract, what arches connect RV to lungs?
aortic arch VI
in partitioning outflow tract, what arches connect LV to body?
aortic arch II and IV
what is necessary for separate V to r and L?
shift of av canal to r side so AV cushion can fuse (myocardialization)
conotruncal septum is formed from?
conotruncal ridge cushion tissue 180 spiral down toward ventricular septum
formed by NCC and endocardial derived cushion tissue
what is bulbus cordis?
outflow tract, makes the ventricular system
