24. Great vessels, Fetal circulation, Changes at birth

Question 1

Explain how the conus cardis and truncus arteriosis divide

Answer 1

Conotruncal cushions grow towards the midline and fuse
Spiral 180 in the process
Grow downwards and fuse with endocardial cushion tissue
Spiral course accounts for intertwining path of pulmonary and aortic vessels and places them at the opening of the correct ventricles

Question 2

Name 4 conditions that arise as a result of abnormal division of the conus cardis and truncus arteriosis

Answer 2

VSD
Tetralogy of Fallot
Transposition of the great vessels
Persistant truncus arteriosis

Question 3

What 4 conditions make up the tetralogy of fallot?

Answer 3

Pulmonary infundibular stenosis
Right Ventricle hypertrophy
VSD
Overriding aorta

Question 4

Describe the normal development of the aortic arches

Answer 4

Arteries in the head and neck form a series of arches on either side of the pharynx
These arise from an extension of the outflow tract of the heart called the aortic sac

Question 5

What is the result of a double aortic arch?

Answer 5

Difficulty swallowing due to arches on both sides of oesophagus

Question 6

What developmental variations are associated with development of aortic arches?

Answer 6

Double aortic arch
Coarctation of aorta
Patent ductus arteriosis

Question 7

What are the 3 pairs of veins that develop in the embryo?

Answer 7

Vitelline
Umbilical
Cardinal

Question 8

What do the vitelline veins become?

Answer 8

Portal system

Question 9

What does the left umbilical vein become?

Answer 9

Ligamentum teres

Question 10

What does the ductus venosus become?

Answer 10

Ligamentum venosum

Question 11

What does the foramen ovale become?

Answer 11

Fossa ovale

Question 12

What does the ductus arteriosus become?

Answer 12

Ligamentum arteriosum

Question 13

What do the umbilical arteries become?

Answer 13

Medial umbilical ligaments