Embryology 2 Flashcards
define vasculogenesis
the new formation of a primitive vascular network
define angiogenesis
growth of new vessels from pre-existing blood vessels
fate of the 1st and 2nd aortic arches
become the maxillary arteries
fate of the third aortic arch
Common carotid and first part of internal carotid arteries
fate of the 4th aortic arch on the left side
arch of the aorta (Distal portion)
fate of the 4th aortic arch on the right side
Right subclavian artery (proximal portion)
fate of the 6th aortic arch on the right side
Becomes right pulmonary artery
fate of the 6th aortic arch on the left side
Becomes left pulmonary artery and ductus arteriosus
what happens to the 5th aortic arch
either never forms or form incompletely and then disappears
when does the lymphatic system develop
at the end of the 6th week develops around main veins
what are the first arteries to appear in the embryo?
left and right primitive aortae - each primitive aortae has a ventral and dorsal part
after the fusion of 2 endothelial tubes… the 2 ventral aortae partially fuse to from what?
aortic sac
how many aortic arch pairs are formed
6

what do most defects of the great arteries arise as a result of? (2)
persistence of aortic arches that normally should regress or regression of arches that normally shouldn’t
what is aberrant (abnormal) subclavian artery
a rare congenital anomaly that usually does not produce symptoms vascular anomaly of the aortic arch right subclavian artery has an abnormal origin on the left side To supply blood to the right arm, this forces the right subclavian artery to cross the midline behind the trachea and oesophagus, which may constrict these organs

double aortic arch - watch out for in OSPE
another congenital aortic arch anomaly occurs with the development of an abnormal right aortic arch in addition to the left aortic arch, forming a vascular ring around the trachea and oesophagus, which usually causes difficulty breathing and swallowing.

Patent ductus anteriosus PDA
ductus arteriosus fails to close after birth Early symptoms are uncommon but in the first year of life include increased ‘work of breathing’ and poor weight gain. An uncorrected PDA may lead to congestive heart failure with increasing age. females > males common link with maternal rubella infection can be genetic or incidental
coarctation of the aorta
congenital condition aorta is narrow, usually in the area where the ductus arteriosus (ligamentum arteriosum after regression- connects pulmonary artery with aorta) inserts. The word “coarctation” means narrowing. Coarctations are most common in the aortic arch. Can be proximal to ductus arteriosus (preductal) or distal to it (postductal). (Co = Coarctation site).

what are the 3 major areas of embryo
yolk sac placenta aortic arch area
names of circulations for:- 1. yolk sac 2. placental 3. rest of body
- vitelline 2. umbilical 3. cardinal
what is the fate of the vitelline arteries in embryo vs adult?
In embryo vitelline arteries supply the yolk sac In adult are represented by arteries to the foregut, midgut & hindgut
umbilical arteries before and after birth
Before birth:- Paired branches of the dorsal aorta to placenta After birth:- Proximal portion persists as internal iliac and superior vesical branches to urinary bladder
embryonic venous system
Vitelline veins – Carrying blood from the yolk sac to the sinus venosus Umbilical veins – originate from chorionic villi of placenta carrying oxygenated blood to the embryo Cardinal veins – draining the body of embryo
where do vitelline, umbilical and cardinal veins drain to?
the right atrium