Development of Great Vessels Flashcards
when does vasculature start to develop
middle of week 3
what does the heart come from
splanchnic mesoderm
dorsal mesocardium
holds the primitive heart tube against the pericardial cavity
forms the transverse pericardial sinus
what forms the epicardium
atrial cells
ventrical region
bulbus cordis and primative ventricle
atrial region
primative atrium and sinus venosus
movement of ventricular region
down and right
movement of atrial region
up and left
dextrocardia
looping in the opposite direction resulting in heart on the right
what is cardiac looping for
basic heart shape
puts the heart on the left
creases and colds that make regions more recognizable
truncus arteriosus (distal) of the bulbus cordis forms
roots/proximal part of aorta and pulmonary trunk
conus cordis (middle) of the bulbs cordis becomes forms
outflow tracts of ventricles
RV- conus arteriosus
LV aortic vestibule
proximal part of bulbus cords becomes the
trabeculated portion of RV
primitive ventricle forms the
trabeculated portion of LV
primitive atrium forms the
trabeculated portion of RA and LA
sinus venous forms the
smooth part of RA (sinus venarum) and the coronary sinus
aortic sac
distal truncus arteriosus
left aortic arch 4 becomes
aortic arch- from left common carotid to left subclavian
right aortic arch 4 becomes
right subclavian artery
left aortic arch 6 becomes
ductus arterioles and left pulmonary artery
right aortic arch 6 becomes
right pulmonary artery
what do aortic arches travel with
pharyngeal arches
what does the aortic arch form
brachiocephalic trunk and proximal aortic arch
umbilical arteries
start from the dorsal aorta and supply placenta
then make connection with the common iliac artery and lose the original connection
persist proximally as superior vesicle arteries and the distal parts obliterate and form the medial umbilical ligaments
vitalline arteries
supply yolk sac and then fuse to for the arteries of dorsal gut mesentery (celiac trunk, SMA, IMA)
septum transversum
anchoring of the venous pole
becomes the central tendon of the diaphragm and the pericardial sac attachment site
what 3 veins drain into the sinus venosus
cardinal
vitelline
umbilical
cardinal veins
drain deoxygenated blood from embryo body
become the caval system (IVC, SVC)
vitelline veins
drain deoxygenated blood from yolk sac
becomes the hepatic portal system
umblical veins
brings oxygenated blood from the placenta to the embryo
right- round ligament of the liver
left- degenerates
what forms septa
endocardial cushions
atrioventricular septum formation
ventral and dorsal endocardial cushions
valve formation between atria and ventricles
superior and inferior endocardial cushions
atria septum formation
2 septa from the roof to form an overlapping valve
septa primum
grows down from superior AV endocardial cushions to meet the atrioventricular septum (almost)
ostium primum
opening between septum primum and endocardial cushions
closed when septa primum fuses with atrioventricular cusions
ostium secondum
cell death creates an opening in the supper septum primum
septum secundum
grows down from roof next to the septa primum and does not use with the atrioventricular septum
foamen ovale
opening in the intra-atrial septa that lets blood through
formation of fossa ovalis
LA pressure exceeds RA pressure and closes the foramen ovale
ostium secondum defect
atrial septa defect caused by:
excessive resorption of septum primum
absence of septum secondum or absence of both septa
effects of an atrial septa defect
blood shunted from LA to RA resulting in overloading of the RA, RV and pulmonary arteries which causes pulmonary hypertension
patent foramen ovale
incomeplete fusion of septa after birth
not clinically significant
formation of septum between aorta and pulmonary trunk
endocardial cushions in conus cordis and truncus arteriosus form and grow toward the midline, fuse and spiral around each other 180 degrees
–> why aorta and pulmonary trunk are wrapped around each other
pulmonary trunk ends up on right, aorta ends up on left
pulmonary trunk is anterior, aorta is posterior
tetralogy of fallot
abnormal neural crest cell migration resulting in anterior displacement of conotruncal septum pulmonary stenosis ventricular septal defect overriding aorta right ventricular hypertrophy
formation intraventricular septum
down growth of endocardial cushions form the membranous part
upgrowth from inferior wall form the muscular part
ventricular septum defect
most common abnormality– abnormal membranous part of septum
leads to L to R shunt and pulmonary hypertension
persistant truncus arteriosus
abnormal crest cell migration which results in partial development of the conotruncal septum–> 1 trunk leaves
always combined with a VSD
transposition of great vessels
nonspirnal development of conotruncal septum resulting in aorta coming from RV and pulmonary trunk coming from RV
ductus venosus
bypasses liver by connecting the umbilical vein to the iVC
regulates flow into heart when maternal intraabdominal pressure changes
becomes ligament venosus
foramen ovale
bypasses lungs by connecting RA to LA
becomes fossa ovalis
ductus arteriosus
connects pulmonary trunk with aorta
becomes ligament arteriosus
patent ductus arteriosus
most frequent abnormality
failure of ductus arterioles to close resulting in oxygenated blood from aorta going into pulmonary artery
