heart evolution

1. Development of circulatory system
1. Establishment of primitive cardiovascular system
2. Development of heart
(1) Formation of primitive heart
(2) Establishment of configuration of heart
(3) Compartmentation of heart
3. Blood circulation of fetus
4. Abnormality of circulatory system

2. Establishment of primitive
cardiovascular system
 Development of blood vessel First: extraembryonic
Second: endoembryonic
1. Extraembryonic (15th to 16th day)
Extraembryonic mesoderm
(Yolk sac)
Blood
island
Endothelial
tubule
(periphery)
Endothelial
tubular
meshwork
Primitive
blood cells
(center)
Extraembryonic mesoderm
Body stalk, Chorion
Endothelial
tubular
meshwork

3. 2. Endoembryonic (18th to 20th day)
Endoembryonic
mesoderm
(Mesenchyme)
Endothelial
tubule
Endothelial
tubular
meshwork
3. The end of 3rd week
Endoembryonic Body stalk Extraembryonic
Communication
Primitive cardiovascular system

4. Formation of blood island and blood vessel
Extraembryonic
mesoderm
Primitive
blood cells
Endothelium

5. Development of primitive heart
 Formation of primitive heart
Cardiogenic
region
Pericardiac
coelom 2
（dorsal）
Cardiogenic
plate 2
（Ventral）
Cardiac
tube 2
Head
fold
Cardiac
tube 2
Pericardiac
coelom 2
18th-19th
day
Cardiac
tube 1
Pericardiac
coelom 1
Fusion
Fusion

6. Head fold:
Pericardiac coelom: dorsal → ventral
Cardiac tube: ventral → dorsal

7. 1
2
3 4
Lateral fold:
Pericardiac coelom: 2 → 1
Cardiac tube: 2 → 1
Pericardiac
coelom Cardiac
tube
Foregut
Cardiac
tube
Cardiac
jelly
Dorsal
mesocardium
Myocardium

8. Establishment of configuration of heart
Straight tube
Bulbus cordis —Ventricle— Atrium—Sinus venosus
2 shrink
Pericardial
fixation
Pericardiac
fixation
（21th day）
(4th to 5th week)
S-shaped
Heart rudiment (35th day)
U-shaped
bulboventricular loop

9. Cardiac
tube
Ventricle
Bulbus
cordis
Atrium
Sinus
venosus
Distal：slightness, truncus arteriosus
Middle：dilation, bulbus arteriosus cordis
Proximal：primitive right ventricle
Left horn
Right horn
Bulboventricular
loop Protruding to right, ventral and tail

10. Establishment of configuration of heart
Ventricle
Atrium
Truncus
arteriosus
Bulbus
cordis

11. Establishment of configuration of heart

12. Ventral
endocardiac
cushion
Dorsal
endocardiac
cushion
Atrioventricular
tube
Left
atrioventricular
tube
Right
atrioventricular
tube
Compartmentation of heart
27-37th day
1.Compartmentation of atrioventricular tube

13. Compartmentation of primitive atrium
( 4th to 5th week)
 Septum primum: end of 4th week
Foramen primum：
Foramen secundum:
Foramen ovale:
Valve of foramen ovale:
 Septum secundum: end of 5th week

14. Right atrium
Left atrium
Foramen primum
Septum primum
Closing
foramen
primum
Foramen
secundum
Forming
foramen
secundum
Right
ventricle
Septum
secundum
Left
ventricle
Valve of
forasmen
ovale
Foramen
ovale

15. Compartmentation of primitive atrium

16.  Muscular interventricular septum：end of 4the week
Compartmentation of primitive ventricle
( 4th to 8th week)
 Membranous interventricular septum: end of 7th week
Interventricular foramen:
Three origins: left, right bulbar ridge and
endocardiac cushion

17. Left atrium
Foramen primum
Septum primum
Closing
foramen
primum
Foramen
secundum
Forming
foramen
secundum
Right
ventricle
Septum
secundum
Left
ventricle
Valve of
foramen
ovale
Foramen
ovale
Interventricular
foramen
Muscular
interventricular
septum
Membranous
interventricular
septum

18. Development of heart (6th week)
Muscular
interventricular
septum

19. Right bulbar ridge
Left bulbar ridge
Aortico-pulmonary
septum
Endocardiac cushion
Membranous
interventricular
septum
Interventricular
foramen
Muscular
interventricular
septum
Formation of membranous septum

20. Compartmentation of truncus arteriosus
and bulbus cordis (5th to 8th week)
Inner part
of truncus
arteriosus
and bulbus
cordis
Left, right
Bulbar ridge
(Spiral)
Fusion
Aorta
Pulmonary
artery
Aortico-
pulmonary
septum
（Spiral ）

21. Right bulbar ridge
Aortico-
pulmonary
septum
Left bulbar ridge

22. Development of heart (6th week)
Bulbar
ridge

23. Aortico-pulmonary septum
Right pulmonary artery
Aorta
Aortico-pulmonary septum
Compartmentation of truncus
arteriosus and bulbus cordis

24. Blood
circulation
of fetus

25. Venous
ductus

26. Arterial
ductus

29.  Characteristics
Ductus－－A ductus、V ductus
Foramen－－Foramen ovale
3
2
1
Umbilical vessels－－2 A , 1 V

30. Alterations after birth
①Foramen ovale atresia
②Umbilical vessels atresia
③V ductus atresia
④A ductus atresia

31. Abnormality of circulatory system
１. Atrial septal defect
２. Ventricular septal defect
３.Abnormal compartmentation of truncus arteriosus
４. Patent ductus arteriosus

32. １. Atrial septal defect
Reasons：
Perforation of foramen ovale
Over absorption of septum primum
Undeveloped septum secundum
Unclosed foramen ovale
①
②
③
④
① ②
③ ④
= ② + ③

33. ２. Ventricular septal defect
Reasons:
① Unfused endocardial cushion,
bulbar ridge and muscular septum
② Over absorption of membranous
septum
① Membranousr septal defect: commonly
②Muscular septal defect: sparsely
Right ventricle
Left ventricle
Interventricular
foramen

35. Abnormal compartmentation of truncus arteriosus
Reasons:
No spiral
①Incorrectly positioned of aorta
and pulmonary artery
Right ventricle Left ventricle
Aorta
Pulmonary
artery

36. Reasons:
Unequal
compartmentation
of aorta and
pulmonary artery
②Narrow of aorta or
pulmonary artery
Narrow pulmonary artery
Abnormal compartmentation of truncus arteriosus

37. Abnormal compartmentation of truncus arteriosus
Reasons:
Unequal compartmentation
of aorta and
pulmonary artery
③Tetralogy of Fallot
Narrow pulmonary artery, ventricular septal defect,
aorta stride and right ventricle hypertrophy
Roght ventricle
Left ventricle

39. Patent ductus arteriosus
Ductus
arteriosus
remains
open

40. Right
positioned
heart