Embryology 1 (cardio) Flashcards
Circulatory system forms from the
lateral plate splanchnic mesoderm
Primordial heart starts to function at the beginning of
week 4
Blood vessels first appear in the wall of the
yolk sac
allantois
connecting stalk
chorion
Angioblastic cords canalize to form
heart tubes
Pericardium is derived from
intra-embryonic coelom
Parietal layer of serous pericardium and fibrous pericardium are derives from the
somatic mesoderm
Visceral layer of the serous pericardium is derived from the
splanchnic mesoderm
Vitelline vein gets. venous blood from the
yolk sac
umbilical vein gets venous blood from
placenta
common cardinal vein gets venous blood from
body of the embryo
Aortic arches arise from the
aortic sac
aortic arches terminate at the
dorsal aorta
How many aortic arches are there?
6
…… and the ….. grow faster than other regions of the primitive heart tube - forming a U-shaped …….
bulbs cordis
ventricles
bulboventricular loop
Abnormal cardiac looping leads to
dextrocardia
in dextrocardia - the heart loops to the
left instead of the right
clinical abnormalities involved in abnormal development of endocardial cushions and septum formation
atrial septum defect
ventricular septum defect
septum formation allows for the creation of
left and right atrium
left and right ventricles
endocardial cushion formation allows for the
separation of the right and left AV canals
Partitioning of the primordial atrium into left and right atria starts at
the end of week 4
Foramen ovale is an opening in
septum secundum
Common atrial septal defect
patent foamen ovale
Four clinically significant types of ASD
foramen secundam defect *
endocardial cushion with Forman premium defect *
sinus venous defect
common atrium
*these two are the most common
Role of oval foramen before birth
allows most of the blood to pass from the right to the left atrium
Role of oval Foramen after birth
normally closes
septum primum fuses with the septum secundum
non-closure of oval foramen
atrial septal defect
oval fossa of the adult heart is a remnant of
foetal oval foramen
Bulbus cordis and trunks arteriosus undergo a 180 degree turn to from the
aorticopulmonary septum
The aorticopulmonary septum divides the BC and TA into the
aorta and pulmonary trunk
SA node develops during the …… week
5th
adult location of the SA node
high in the right atrium near the entrance of the SVC
SA node
pacemaker
Fate of aortic sac
aortic arches
fate of bulbs cordis
right ventricle
parts of the outflow tracts
fate of the primitive ventricle
left ventricle
fate of the primitive atrium
parts of the right and left atria
fate of the sinus venous
SVC
right atrium