The document discusses congenital heart disease (CHD), including its classification into cyanotic and acyanotic types based on blood flow direction and presence of shunts or obstructions. Common acyanotic defects are atrial and ventricular septal defects and patent ductus arteriosus, which allow left-to-right shunting. Cyanotic CHDs include tetralogy of Fallot and transposition of the great vessels, characterized by right-to-left shunting and cyanosis. Obstructive lesions such as aortic coarctation can also occur. The etiology involves both genetic and environmental factors, and clinical severity depends on the degree of stenosis and patency of ductal structures.

1. Congenital heart disease
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2. Specific learning objectives
• Hemodynamics of congenital heart disease
• Various subtypes and the basis for the classification
• Differences between cyanotic and acyanotic heart
disease
• Concept of Eisenmenger syndrome
• Salient features of important entities
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3. Why should we learn about CHD ?
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4. 30%
70%
Congenital defects
CHD Other
6-8 out of 1000 births
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5. Single
chamber
Particular
region
It is a live birth with CHD if …..
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6. Embroyo
3-8 wks
Unknown
90%
Tetratogen
RubellaDiabetes
Choromosomal
anomaly
Etiology
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7. Morphogenesis
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progenitor
cells
looping of
the heart
tube
segmentation
and growth of
the cardiac
chambers
Valve
formation
Connection of
vessels
Wnt, VEGF, BMP, TGF-
β, FGF and Notch
pathway
Pulsalite blood flow

8. Transcription
factors
Intracellular
signalling
Micro RNAsEpigenetics
Noonan Holt
Oram
DiGeorge
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9. Sub-Groups
Left to Right
Right to Left
Obstruction
to flow
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10. Flow depends upon the
pressure gradient
Shunt
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11. Lung is
bypassed
Cyanosis
Right to Left
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12. Increased
pulmonary blood
flow
Adaptive
changes
RVH
Shunt
reversal
Cyanosis
Left to Right
Esienmenger
Syndrome
Inoperable
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13. Obstruction
Valve
Vessel
Chamber
Atresia – complete obstruction
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14. Adaptive changes
Hypertrophy
Hypoplasia (in utero)
Atrophy
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15. • Most common
• Types
– Atrial septal defects (ASDs)
– Ventricular septal defects (VSDs)
– Patent ductus arteriosus (PDA)
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Left to right shunts

16. Sinus venosus
Septum Primum
Right
Atrium
Left
Atrium
ASD / Patent foramen ovale
Septum
Secundum
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17. Foramen
ovale
80% fuse
20% open – may cause
paradoxical embolism
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18. Inter
Atrial
Septum
Sinus
venosus
5%
Ostium
secondum
(90 %)
Ostium
primum
5%
RA /RV enlarged
RVH, Pul HTN
Anomalus
drainage of Pul
veins to RA
MV / TV affected
VSD / AV canal1/18/2016 Dept of Pathology 18

19. Ventricular septal defect
Right
Ventricle
Left
Ventricle
Membranous
Muscular
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20. Inter
Ventricular
Septum
90%
10 %
Most common
Most close spontaneously
Only 20%
occur in
isolation
RV enlarged
RVH, Pul HTNEndocarditis !
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21. Patent ductus arteriosus
Close - ↑Pressure,
↓PGE2
Ligamentum
arteriosum
Hypoxia , RDS
delayed closure
90% isolated
Machinery
murmur
May be
required to
maintain
patency
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22. • Early cyanosis
• Types
– Tetralogy of Fallot (TOF)
– Transposition of great vessels (TGV)
• Clubbing (hypertrophic osteoarthropathy),
polycythemia, and paradoxical embolization
Right to left shunts
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23. Tetralogy of Fallot
Boot shaped heart
VSD,
Overriding aorta,
Pul stenosis
RVH
PDA / bronchial a.
essential for lungs
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24. Transposition of great vessels
Aortopulmonary /
truncal septae
defect
VSD, ASD, PFO,
PDA required for
survival
RVH, Hypoplasia
of LV
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25. Obstructive
• At level of
• heart valves
• more distally within a great vessel
• proximal to the valve
• Common examples
• Pulmonic valve stenosis
• aortic valve stenosis or atresia
• coarctation of the aorta
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26. Coarctation of Aorta
Male,
Turner’s
Asso with
Bicuspid
Aortic valve
Infantile –
RVH,
Pul a. dilation,
LL Cyanosis
Adult –
LVH,
HTN
Notching of
ribs
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27. Summary
• defects of chambers or vessels
• shunting or obstructions
• asymptomatic to fatal
• Environmental and genetic causes
• Left-to-right shunts - most common (ASDs, VSDs, or
a PDA)
• Eisenmenger syndrome
• Right-to-left shunts – TOF , TGV
• cyanosis and associated with polycythemia,
clubbing and paradoxical embolization
• Obstructive lesions - aortic coarctation
• clinical severity - degree of stenosis and patency
of the ductus arteriosus
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28. Questions ?
Clarifications ?
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