17. CP Great Vessels Embryology Flashcards
When does vasculogenesis begin?
By the end of the third week
What are the first to loci for the formation of blood islands?
Extraembryonic splanchnic mesoderm (around the yolk sac)
Aortic gonad mesonephric region (AGM)
What arises from aortic arch 1?
External carotid
Maxillary
What arises from aortic arch 2?
Stems of the stapedial arteries
What arises from the aortic sac?
Brachiocephalic artery
Base of the arch of the aorta
What arises from aortic arch 3?
Internal carotid
Common carotid
What arises from aortic arch 4?
Left: medial portion of the arch of the aorta
Right: proximal right subclavian (distal part comes from the 7th segmental artery, and another part comes from the dorsal aorta)
What arises from arch 6?
Pulmonary arteries
Left: Distal ductus arteriosus
Right: Distal portion degenerates
What arises from the 7th segmental artery?
Left: Entire left subclavian
Right: Distal part of the right subclavian (the proximal part came from arch 4, and another part comes from the dorsal aorta)
What arises from the dorsal aorta?
Right: Portion of the right subclavian (the proximal part comes from arch 4 and the distal part from 7th segmental artery)
Left: Descending aorta
What vessel brings oxygenated blood from the placenta to the newborn?
The left umbilical vein
What structure allows placental blood to bypass the fetal liver?
The ductus venosus
What do we call the neonatal remnant of the left umbilical vein?
The ligamentum teres (round ligament of the liver)
What is the embryological structure that becomes the ligamentum venosum?
Ductus venosus
What signaling molecule assists in the closure of the ductus arteriosus?
What signaling molecule can keep it open?
Bradykinin
Prostaglandins
What causes a double aortic arch?
Persistence of the distal portion of the right dorsal aorta (proximal portion makes a part of the right subclavian like it’s supposed to - but then the distal portion remains.
What causes an interrupted aortic arch?
Abnormal disintegration of both of the 4th aortic arch arteries
What genetic defect is often associated with an interrupted aortic arch?
DiGeorge Syndrome (22q11 deletion)
Which upper extremity (right or left) always gets blood in patients with an interrupted aortic arch?
The right side upper extremity.
Left side sometimes does, sometimes doesn’t. Lower extremity depends on the ventricular septal defect and patent ductus arteriosus.
What is the function of the vitelline veins?
Returning blood from the yolk sac and liver to the heart.
Proximal to the heart, which vitelline vein degenerates, and which persists?
Left vitelline degenerates near the heart, but the right vein persists
What are the fates of the right and left vitelline veins in the liver?
Right gives rise to the hepatic vein (part of inferior vena cava)
Right and Left both give rise to the portal vein
What part of which umbilical vein persists to bring O2 rich blood back from the placenta?
The distal portion of the left umbilical vein
What blood vessels arise from the anterior cardinal veins?
Right: Superior vena cava
Left: Brachiocephalic Vein
What blood vessels arise from the posterior cardinal veins?
Subcardinal veins
Supracardinal veins
Root of the azygos vein
Common iliac vein
What defect results in a left superior vena cava?
Obliteration of the right common cardinal vein and the proximal part of the right anterior cardinal vein.
(Thus the superior vena cava has to come from the left, since the right is gone)
What defect results in a double superior vena cava?
Failure of the left brachiocephalic vein to form, resulting in it forming another vena cava.
Where do left sided superior vena cavas drain?
Into the coronary sinus.
What structure gave rise to the following segment of the inferior vena cava:
Hepatic
Hepatic veins and sinuses
Right Vitelline
What structure gave rise to the following segment of the inferior vena cava:
Pre-renal
Right Subcardinal
What structure gave rise to the following segment of the inferior vena cava:
Renal
Subcardinal-supracardinal anastomosis
What structure gave rise to the following segment of the inferior vena cava:
Postrenal
Right Supracardinal
