Development of the great vessels

Question 1

Sinus venosus –> sinus venarum in an adult

Answer 1

Right atrium (sinus of vena cava, smooth)

Question 2

Sinus venosus in an adult

Answer 2

Vena cava (exp SVC)
Coronary sinus

Question 3

Primordial atrium in an adult

Answer 3

Right and left auricles

Question 4

Pulmonary veins in an adult

Answer 4

Left atrium (smooth)

Question 5

Primordial ventricle in an adult

Answer 5

Left ventricle

Question 6

Bulbus cordis - proximal 1/3 in an adult

Answer 6

right ventricle

Question 7

Bulbus cordis - middle 1/3 (conus cordis) in an adult

Answer 7

Infundibulum (RV) and aortic vestibule

Question 8

Bulbus cordis - distal 1/3 (trunks arteriosus) in an adult

Answer 8

roots and proximal parts of pulmonary trunk and aorta

Question 9

Aortic sac in an adult

Answer 9

proximal aortic arch and proximal brachiocephalic trunk

Question 10

What does the right 3rd arch form

Answer 10

right common carotid artery

right internal carotid artery

Question 11

What does the left 3rd arch form?

Answer 11

left common carotid artery

left internal carotid artery

Question 12

What does the 4th right arch form?

Answer 12

right proximal subclavian artery

Question 13

What does the 4th left arch form?

Answer 13

aortic arch (middle)

Question 14

What does the 6th right arch form?

Answer 14

right pulmonary artery

Question 15

What does the 6th left arch form?

Answer 15

left pulmonary artery

ductus arteriosus

Question 16

What does the right 7th IS artery form?

Answer 16

right distal subclavian artery

Question 17

What does the left 7th IS artery form?

Answer 17

left subclavian artery

Question 18

What does the right dorsal aorta form?

Answer 18

right distal subclavian artery

Question 19

What does the left dorsal aorta form?

Answer 19

descending aorta (distal aortic arch)

Question 20

Embryology and cause of patent foramen ovale

Answer 20

Foramen vale is a defect on septum secundum, which is connected with osmium secundum (on septum primum)
Caused by failure of fusion of either results in patent foramen ovale

Question 21

Embryology and cause of patent ductus arteriosus

Answer 21

Ductus arteriosus is the connection between 6th aortic arch and left dorsal aorta. After full development, it extends between pulmonary trunk and aorta (distal to the origin of the left subclavian artery)
No clear cause; chromosomal abnormalities, prematurity, low birth weight, prostaglandins, high altitude and low atmospheric oxygen tension, hypoxia

Question 22

Embryology and cause of atrial septal defect (osmium primum defect is a form of ASD)

Answer 22

IA septum is formed by septum primum and septum secundum

Caused by failure of proper development of septum secundum OR failure of closure of ostium primum

Question 23

Embryology and cause of ventricular septal defect (most common)

Answer 23

IV septum is derived from endocardial cushion (membranous) and walls of primordial ventricle and bulbs cordis (muscular)
Caused by a defect in either the membranous (more common) or muscular portion of IV septum
or failure of fusion of membranous muscular portions

Question 24

Embryology and cause of Tetralogy of Fallot (VSD, pulmonary artery stenosis, deviation if the aortic origin to the right (overriding aorta), hypertrophy of RV)

Answer 24

Caused by unequal division of conus cord with resultant anterior displacement (malalignment) of the aorticopulmonary septum

Question 25

Embryology and cause of Transpotition of the great vessels

Answer 25

Caused by failure of the articopulmonary (conotruncal) septum to spiral

Question 26

Embryology and cause of coarctation of the aorta (narrowing of the aorta, usually distal to the origin of the left subclavian artery from the arch of aorta

Answer 26

No clear cause; contraction of ductus arteriosus