Embryology of major vessels. How superior and inferior vena cava are developed in heart of the embryo. Major vessels develop within one month of fertilization. It is the first system to develop in the human body.

1. Development of Superior vena
cava, Inferior vena cava and
coronary sinus.

2. Five dilations of heart tube
Aortic sac
Truncus arteriosus
Primitive atrium
Bulbus cordis
Primitive ventricle
Sinus venosus

3. Venous end of heart tube

5. Fate of Five dilations of heart tube
Aortic sac
Truncus arteriosus
Primitive atrium
Bulbus cordis
Primitive ventricle
Sinus venosus
Partitioned to form pulmonary
trunk & ascending aorta
Bulbus cordis and ventricle fuse
to form common ventricle which
partitioned to become right and
left ventricles
Is partitioned to become rough
part of right and left atria
Central part & right horn of sinus
venosus are absorbed to form
smooth part of rt. Atrium. The lt.
horn forms coronary sinus

6. Fate of sinus venosus

7. Venous end of heart tube

9. Three set of Primary veins

10. Fate of umbilical and vitelline vein

11. Fate of umbilical and vitelline vein

13.  After birth
Left umbilical vein obliterates to form ligamentum
teres
Ductus venosus obliterates to form ligamentum
venosum

14. Development of SVC

15. Development of SVC

16. Development of SVC

17. Posterior cardinal vein

18. Dev. of IVC

19. Development of Inferior vena cava

20. Thank you