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CONGENITAL HAERT
DISEASE2
The Heart
CLASSIFIACTION OF CHD
(Functional)
• Obstructive Congenital Heart Lesions
• Congenital Heart Lesions that INCREASE
Pulmonary Arterial Blood Flow
• Congenital Heart Lesions that DECREASE
Pulmonary Arterial Blood Flow
Obstructive Congenital Heart Lesions
 Impede the forward flow of blood and
increase ventricular afterloads.
• Pulmonary Stenosis
• Aortic Stenosis
• Coarctation of the Aorta
Congenital Heart Lesions that INCREASE
Pulmonary Arterial Blood Flow
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Atrial Septal Defect
Complete Atrioventricular Canal
Ventricular Septal Defect
Patent Ductus Arteriosis
Total Anomalous Pulmonary Venous
Connection
• Truncus Arteriosus
Congenital Heart Lesions that DECREASE
Pulmonary Arterial Blood Flow
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Tetralogy of Fallot
Transposition of the Great Arteries
Tricuspid Atresia
Ebstein’s Anomaly
CONGENITAL HAERT DISEASE
• Congenital heart diseases encompass a broad
spectrum of malformations ranging from mild
lesions that produce minimal symptoms until
adult life to severe anomalies that cause death
in the perinatal period.
• The cause of most cases of congenital heart
disease is unknown.
 Genetic and environmental factors (eg.
congenital rubella infection) are responsible for
some cases.
• Some common defects like foramen ovale and
bicuspid aortic valve are not clinically significant
Foramen ovale
• Foramen ovale
 is situated in the inter-atrial wall & is covered by a
moving flap of tissue on the left atrial side.
 In intrauterine life, foramen ovale allows blood
flow from right to left atrium, during systole
(high right atrial pressure from collapsed lung).
 During diastole, foramen is closed by the flap
of tissue due to high left atrial pressure.
 After birth, Foramen is permanently closed
within 1-2 days after birth. (low right atrial
pressure due to airy lung & high left atrial
pressure)
Incidence:
• Figures of incidence derived from several sources are as
follows:
• Ventricular septal defect (30-33 %)
• Atrial septal defect (5-8 %)
• Patent ductus arteriosus (8-10 %)
• Tetralogy of Fallot( 8-9 %)
• Pulmonary stenosis (8-10 %)
• Aortic stenosis or atresia (6-8 %)
• Coarctation of aorta (5-6 %)
• Transposition of great arteries (5-10 %)
• Total anomalous pulmonary venous connection (1-2 %)
• Truncus arteriosus (1-2 %)
Ventricular Septal Defect:
Three types of VSD
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Perimembranous VSD – most common
Muscular VSD – can be multiple
Apical VSD – usually small
Variable in size
Ventricular Septal Defect
Ventricular Septal Defect:
• Is is an abnormal opening in the ventricular septum that
allows free communication between left and right
ventricles.
• This is the most common congenital cardiac anomaly.
• This is often associated with Tetralogy of Fallot.
• Mostly (90 %) involves the membranous septum near
the aortic valve.
• Interventricular septa develop from above downwards
hence, in most of the cases, septal defects are seen in
the basal region, which closes last.
• These patients are at increased risk of infective hepatitis
Ventricular Septal Defect
• Hole between the two ventricles
• Left to right shunt – majority
• Dilated right heart – too much blood to
lungs – increase in pulmonary pressure
• Smaller defects can close spontaneously
Atrial Septal Defect (ASD)
Atrial Septal Defect (ASD)
Three types of ASD
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Primum ASD
Secundum ASD
Sinus venosus
AVSD – Atrio ventricular septal defect
Atrial Septal Defect:
• This is an abnormal opening in the atrial septum that
allows free communication of blood.
• This is the most common congenital cardiac anomaly
presenting in adults and are three types:
• i) Primum type:
 It is common in Down syndrome.
 It occurs low in the atrial septum and occasionally occurs
in association with mitral valve deformities.
• ii) Secundum type:
 This is the commonest type (90 %) and occurs at the
foramen ovale.
• iii) Sinus venosus type:
 It occurs high in the septum near the superior vena cava
entrance
Atrial
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Hole between the two atria
Blood flows left to right
PFO – Patent foramen ovale fails to close
Right heart becomes dilated
Too much blood to the lungs
Patent Ductus Arteriosus:
• The ductus
arteriosus, serves to
shunt blood from
pulmonary artery to
aorta during
intrauterine life.
Persistence of ductus,
which normally closes
soon after birth,
results in left-to-right
shunt.
Patent Ductus Arteriosus:
Patent Ductus Arteriosus:
• In intrauterine life the ductus arteriosus permits
blood flow between the aorta (distal to the left
subclavian artery) and the pulmonary artery.
• In a full-term infant, the ductus usually closes
within the first day or two of life.
• This is due to;
 relatively high oxygen tension and
 reduced local prostaglandin-E synthesis
causing ductal muscular contraction.
• Persistent patency beyond that point is generally
permanent
PDA – patent ductus arteriosus
• Normal fetal structure , allows blood to
bypass circulation to the lungs (O2
provided by placenta)
• Connection LPA to Ao
• Normally closes 24hrs after birth ( hi 02
and low PGE synthesis)
• Can correct several months after birth
Patent Ductus Arteriosus:
• Most of the cases (80-90 %) occur as isolated defects.
• There is associated left ventricle hypertrophy and pulmonary
artery dilation.
• Clinical presentation:
 Initially asymptomatic,
 in some cases there may be shortness of breath and
 poor feeding habits.
• Premature infants and those with respiratory distress
syndrome(RDS) are at increased risk.
• In long-standing case it induces
 pulmonary hypertension with subsequent
 right ventricular hypertrophy and
 finally right-to-left shunt producing cyanosis.
Patent Ductus Arteriosus:
• PDA is also associated with coarctation of the
aorta, transposition of the great vessels, and
ventricular septal defect.
• All the above three conditions i.e. Ventricular
septal defect, atrial septal defect and patent
ductus arteriosus, produce abnormal blood-flow
from the right to left side of heart.
• From the outset there is cyanosis as the poorly
oxygenated blood passes into the systemic
circulation.
• They also permit emboli from venous sources
to pass directly into the systemic circulation
(paradoxic embolism).
PDA - problems
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Shunting of blood Ao to PA
Too much blood going to lungs
Increased PA pressure – increase RV
Long term damage to lungs and heart
Tetralogy of Fallot:
Tetralogy of Fallot:
• Tetralogy of Fallot is due to embryologic anterosuperior displacement of the infundibular septum.
• Its four cardinal features are :
• i) Ventricular septal defect
• ii) Dextroposed aorta overriding the ventricular
septal defect.
• iii) Pulmonary stenosis with right ventricular outflow
obstruction.
• iv) Right ventricular hypertrophy.
• Additional cardiac anomalies may be present.
Cyanosis is present from birth or soon after.
Tetralogy of Fallot:
• Severity of symptoms is directly related to
the extent of right ventricle outflow
obstruction.
• With a large ventricular septal defect and
mild pulmonary valvular stenosis, there is
a mild left-to-right shunt without
cyanosis.
• More severe pulmonary stenosis produces a
cyanotic right-to-left shunt
Tetralogy of Fallot:
With complete pulmonary obstruction,
survival is permitted only by flow through a
patent ductus arteriosus or dilated
bronchial arterial arteries.
• Pulmonary valvular stenosis protects the
lung from volume and pressure overload,
and right ventricle failure is rare owing to
decompression into the left ventricle or
aorta
Transposition of Great Arteries:
Transposition of Great Arteries:
• The aorta arises from the right ventricle and
the pulmonary artery from the left.
• Fetal development occurs as a result of
mixing venous and systemic blood through
the patent ductus arteriosis and a patent
foramen ovale.
• Therefore, postnatal life critically depends on
continued patency of the ductus as well as
ventricular septal defect, atrial septal defect,
or patent foramen ovale.
Transposition of Great Arteries:cont-• Prognosis depends on the severity of
tissue hypoxia and the ability of the right
ventricle to maintain aortic flow.
• If untreated, most children die within the
first few months.
• This is particularly common in children of
diabetic mothers, and
• this malformation causes cyanosis.
Truncus Arteriosus
• This anomaly is due to developmental
failure of separation of the embryologic
truncus areteriosus into the aorta and
pulmonary artery.
• This results in a single great artery that
receives blood from both ventricles
accompanied by an underlying ventricular
septal defect, and that gives rise to the
systemic, pulmonary and coronary
circulation.
Truncus Arteriosus—cont-• Patients present with early cyanosis as a
result of right-to-left shunting.
• Eventually, the flow reverses, and they
develop right ventricle hypertrophy with
pulmonary vascular hypertension.
• The anomaly carries a poor prognosis
Truncus Arteriosus
Coarctation of Aorta
Coarctation of Aorta
Coarctation of Aorta
Coarctation of Aorta - Infant
COARCTATION OF THE AORTA
Coarctation of Aorta
• Coarctation (narrowing or constriction) of
the aorta occurs mainly (50 %) as isolated
defects, the remainder with multiple other
anomalies.
• In most cases, cardiomagaly (chronic
pressure overload hypertrophy) occurs.
• Clinical manifestations depend on the
location and severity of the constriction.
• Most occur just distal to the ductus or
ligamentum arteriosus (postductal).
Coarctation of Aorta
 Preductal coarctation: (Proximal to ductus arteriosus)
• Manifests early in life and may be rapidly fatal.
• Survival depends on the ability of the ductus arteriosus to
sustain blood flow to the distal aorta and lower body
adequately.
• Even then, there tends to be
 lower body cyanosis, where as
 the head and arms are unaffected because their blood supply
derives from vessels having origins proximal to the ductus.
Coarctation of Aorta
• This form usually involves a 1 to 5 cm
segment of aortic root and is often
associated with
fetal right ventricle hypertrophy and
 early right-sided heart failure
Coarctation of Aorta
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Postductal coarctation:
It is generally asymptomatic unless severe.
It usually leads to upper extremity hypertension but
low flow and hypotension in the lower extremities, causing
arterial insufficiency (claudication, cold sensitivity).
• Collateral flow around the coarctation generally develops with
intercostals rib-notching (noted in x-ray) and internal
mammary and axillary artery dilation.
Coarctation of Aorta
• Even without treatment, mean life span is
40 years.
• Death is due to
congestive heart failure,
aortic dissection proximal to the
coarctation,
 intracranial hemorrhage or
infective endocarditis at the site of
narrowing
Pulmonary Valve Stenosis or Atresia
with Intact Interventricular Septum:
• This malformation is the obstruction (stenosis or
atresia) at the pulmonary valve with intact
interventricular septum.
• It may occur in isolation or with other anomalies
• With complete pulmonary atresia, there is
virtually always a hypoplastic right ventricle and
an atrial septal defect with blood entering the
lungs via a patent ductus arteriosus.
Pulmonary Valve Stenosis or
Atresia with Intact Interventricular
• .Pulmonary stenosis generally caused by the
fusion of the cusps and may vary from mild to
severe.
• Pulmonary outflow obstruction may also be
subvalvular or supravalvular or even multiple.
• Mild stenosis is generally asymptomatic.
Progressively more severe stenoses cause
increasing cyanosis with earlier onset
Aortic Valve Stenosis and Atresia
• Congenital complete aortic atresia is rare and
incompatible with neonatal survival.
• Survival with congenital aortic valve stenosis
(two types- valvular and subvalvular) depends
on the severity of lesion.
• Rarely, single-cusp aortic valves are also seen.
• The fate of this anomaly includes infective
endocarditis, left ventricle hypertrophy (pressure
overload), post-stenotic dilation of the aortic root
and rarely sudden death.
Ebstein’s Anomaly
• The primary abnormality in Ebstein’s Anomaly
is of the tricuspid valve, the valve which lies
between the right atrium and right ventricle.
• While there is free flow of blood forward
across the tricuspid valve to the right ventricle,
• the deformed tricuspid valve allows a large
amount of blood to flow backwards from the right
ventricle to right atrium when the right ventricle
contracts
Ebstein’s Anomaly
• Septal and posterior leaflets of the
tricuspid valve are small and deformed,
usually displaced toward the right
ventricular apex.
• Most patients have an associated ASD or
patent foramen.
• Cyanosis and arrhythmias in infancy are
common.
Ebstein’s Anomaly
Ebstein’s Anomaly
• Right heart failure in half of patients.
• Operative repair with tricuspid valve
replacement.