7. Second week of development:
Bilaminar germ disc
day12 day13
8. Third week of development:
Gastrulation (trilaminar germ disc)
day16
9. 20 days
Neurulation includes
the formation of the
neural plate (day 18-19),
neural folds (day 20-21),
and the neural tube (day
22-26); the latter will
develop into the future
brain and spinal cord
13. Early Cardiac Morphogenesis I
(Fertilization 3rd week)
• Cardiogenic crest in
splanchnic mesoderm in
front of the neural plate
• Bilateral endocardial
tube from angioblastic
cords
• Cephalic and lateral
folding of the embryo
• Primary heart tube in
the middle thorax
18. Abnormalities of Cardiac Looping
• Dextrocardia
– Isolated form
– Situs inversus
• Heterotaxy (Laterality
sequences)
– Polysplenia syndrome-
left isomerism
– Asplenia syndrome-
right isomerism
19. Development of sinus venosus
Fetal stage
ACV: anterior cardinal v. PCV: posterior cardinal v.
UV: umbilical v. VIT: vitelline v. CCV: common cardinal v.
34. Ventricular Septal Defect
• Most common congenital
cardiac malformation
• Isolated or a/w
abnormalities in
partitioning of the
conotruncal region
• Type
– perimembranous (80-90%)
– muscular (5-20%)
– outlet or infundibular,
(doubly committed) juxta-
arterial (5-7%)
35. Perimembranous type
Muscular type
(Doubly committed) juxta-arterial type
Infundibular type
Outlet type
36. Tetralogy of Fallot
• Most common cyanotic CHD
• Conotruncal region 이상
• Unequal division of the conus
resulting from anterior
displacement of the
conotruncal septum
• Four features
1) Ventricular septal defect
2) Subpulmonary stenosis
3) Overriding of aorta
4) Right ventricular hypertrophy
37. Persistent truncus arteriosus
• Conotruncal ridge
– fail to fuse and to
descend toward the
ventricles
– interventricular septum
형성에도 관여하므로 언제나
interventricular septal
defect동반
38. Transposition of Great Arteries
AO
PT
RV
LV
Conotruncal septum
→ fail to follow its normal spiral course and run
straight down
→ Aorta from RV, PA from LV
VSD, perimembranous type 동반하기도.
