Congenital heart diseases

CONGENITAL HEART
DISEASES
Presented by,
Mrs. Arifa T N, Second year M.Sc Nursing (Child Health Nursing ), MIMS CON

Heart
The heart is a muscular organ, which pumps blood.
 Functions
 Delivery of oxygenated blood and other nutrients to all body cells
 Removal of carbon dioxide and other metabolic waste products
 The CVS consist of,
 A pumbing unit (heart)
 A circuit ( arteries, veins and capillaries)
 Numerous valves
 The heart have its own electrical system to maintain its rate and
rhythm and the intrinsic regulatory mechanism controlled by neural
and hormonal system.

 From conception to postnatal period and
childhood, the heart undergoes changes in size,
structure and function.

Introduction
 Congenital heart defects are one of the most
common birth defects, occurring in approximately 1%
of all live births.
 More than 35 types of heart defects have been
documented.
 The incidence of CHD in children is approximately 8
to 12 per 1000 live births.
 CHD is the major cause of death (other than
prematurity) in the first year of life.

Etiology
 The exact cause of most congenital cardiac
defects is unknown.
 Most congenital heart defects develop during the
first 8 week of gestation
 8% known to be associate with a single mutant
gene or chromosomal abnormalities.

 A combined or interactive effect of genetic and environmental factors
 Fetal exposure to drugs (e.g., phenytoin, angiotensin-converting
enzyme [ACE] inhibitors, lithium, warfarin, valproic acid, retinoic
acid) and alcohol
 Maternal viral infections such as rubella or coxsackievirus B5
 Maternal metabolic disorders such as phenylketonuria, diabetes
mellitus, and hypercalcemia
 Increased maternal age
 Multifactorial genetic patterns
 Chromosomal abnormalities (e.g., Turner, Noonan, Marfan,
DiGeorge, and trisomy [13, 18, 21] syndromes)
 A mother with a CHD has an increased risk of having an affected
child.

Classification
 Congenital heart defects are categorized by
pathophysiology and hemodynamics rather than
by the presence of cyanosis.
 Increased pulmonary blood flow
 Decreased pulmonary blood flow
 Obstructed systemic blood flow
 Mixed defects fall into one of these three classifications

Abbreviations…………..
 AS: Aortic Stenosis
 ASD: Atrial Septal Defect;
 AV:Atrioventricular;
 COA:Coarctation of Aorta;
 HLHS:Hypoplastic Left
Heart Syndrome
 MS: Mitral Stenosis
 PDA: Patent Ductus
 PS: Pulmonic Stenosis
 TAPVR: Total Anomalous
Pulmonary Venous Return
 TOF:Tetralogy of Fallot
 TGA: Transposition of
Great Arteries
 VSD:Ventricular Septal
Defect

Defects with Increased Pulmonary Blood
Flow

 In this group of cardiac defects, intracardiac
communications along the septum or an abnormal
connection between the great arteries allows blood
to flow from the higher pressure left side of the heart
to the lower pressure right side of the heart
 Increased blood volume on the right side of the heart
increases pulmonary blood flow at the expense of
systemic blood flow
 ASD, VSD, and patent ductus arteriosus

Atrial Septal Defect
 Abnormal opening between the atria, allowing blood
from the higher pressure left atrium to flow into the lower
pressure right atrium.
 There are three types of ASD:
 Ostium primum (ASD 1): Opening at lower end of septum;
may be associated with mitral valve abnormalities
 Ostium secundum (ASD 2): Opening near center of septum
 Sinus venosus defect: Opening near junction of superior
vena cava and right atrium; may be associated with partial
anomalous pulmonary venous connection

Pathophysiology
Because left atrial pressure slightly exceeds right
atrial pressure, blood flows from the left to the right
atrium, causing an increased flow of oxygenated
blood into the right side of the heart.
Despite the low pressure difference, a high rate of
flow can still occur because of low pulmonary
vascular resistance and the greater distensibility of
the right atrium, which further reduces flow
resistance.

This volume is well tolerated by the right ventricle
because it is delivered under much lower pressure
than with a VSD.
Although there is right atrial and ventricular
enlargement, cardiac failure is unusual in an
uncomplicated ASD.
Pulmonary vascular changes usually occur only
after several decades if the defect is left
unrepaired

Clinical manifestations:
 Patients may be asymptomatic.
 They may develop HF.
 There is a characteristic systolic murmur with a fixed split
second heart sound.
 There may also be a diastolic murmur.
 Patients are at risk for atrial dysrhythmias (probably caused
by atrial enlargement and stretching of conduction fibers) and
pulmonary vascular obstructive disease and emboli
formation later in life from chronically increased pulmonary
blood flow

Diagnostic Tests
 Echocardiogram identifies a dilated right
ventricle due to blood overload and the shunt
size.
 The chest radiograph and ECG reveal little
information unless the ASD is large, has
excessive shunting, and right ventricular
hypertrophy is present.

Surgical treatment
 Surgical patch closure (pericardial patch or
Dacron patch) is done for moderate to large defects.
 Open repair with cardiopulmonary bypass is
usually performed before school age.
 In addition, the sinus venosus defect requires
patch placement, so the anomalous right pulmonary
venous return is directed to the left atrium with a
baffle.
 ASD 1 type may require mitral valve repair or,
rarely, replacement of the mitral valve

Nonsurgical treatment
 ASD 2 closure with a device during cardiac catheterization is
becoming common place and can be done as an outpatient
procedure.
 The Amplatzer Septal Occluder is most commonly used.
 Smaller defects that have a rim around them for attachment of the
device can be closed with a device; large, irregular defects without a
rim require surgical closure.
 Successful closure in appropriately selected patients yields results
similar to those from surgery but involves shorter hospital stays and
fewer complications.
 Patients receive low-dose aspirin for 6 month

 Prognosis: Operative mortality is very low (<0.5%).
The left (long thick arrow) and right atrial (short arrow) disc of an
ASO

Ventricular Septal Defect
 Abnormal opening between the right and left
ventricles.
 Classified according to location:
 membranous (accounting for 80%) or muscular.
 May vary in size from a small pinhole to absence of
the septum, which results in a common ventricle.
 VSDs are frequently associated with other defects,
such as pulmonary stenosis, transposition of the
great vessels, PDA, atrial defects, and COA.

 Many VSDs (20% to 60%) close spontaneously.
 Spontaneous closure is most likely to occur
during the first year of life in children having
small or moderate defects.
 A left-to right shunt is caused by the flow of blood
from the higher pressure left ventricle to the
lower pressure right ventricle

Pathophysiology
• Because of the higher pressure within the left ventricle and because the systemic arterial
circulation offers more resistance than the pulmonary circulation, blood flows through the
defect into the pulmonary artery.
• The increased blood volume is pumped into the lungs, which may eventually result in increased
pulmonary vascular resistance.
• Increased pressure in the right ventricle as a result of left-to-right shunting and pulmonary
resistance causes the muscle to hypertrophy.
• If the right ventricle is unable to accommodate the increased workload, the right atrium may
also enlarge as it attempts to overcome the resistance offered by incomplete right ventricular
emptying

Clinical manifestations
 HF is common.
 There is a characteristic loud holosystolic
murmur heard best at the left sternal border.
 Patients are at risk for BE and pulmonary vascular
obstructive disease
BE:Bacterial endocarditis

Diagnostic Tests
 A chest radiograph and ECG reveal little when VSDs
are small. An enlarged heart and pulmonary vascular
markings on chest radiograph occur in cases of large
VSDs with shunting.
 Right and left ventricular hypertrophy may be seen on
ECG.
 Echocardiogram identifies the size and location of the
defect.

Surgical treatment
Palliative:
 Pulmonary artery banding (placement of a
band around the main pulmonary artery to
decrease pulmonary blood flow) may be done in
infants with multiple muscular VSDs or complex
anatomy.

 Complete repair (procedure of choice):
 Small defects are repaired with sutures.
 Large defects usually require that a knitted Dacron
patch be sewn over the opening.
 CPB is used for both procedures.
 The approach for the repair is generally through the
right atrium and the tricuspid valve.
 Postoperative complications include residual VSD and
conduction disturbances.

knitted Dacron patch be sewn over the opening

 Prognosis:
 Risks depend on the location of the defect, the number
of defects, and the presence of other associated cardiac
defects.
 Single-membranous defects are associated with low
mortality (<1%)
 Multiple muscular defects can carry a higher risk for
infants, as well as infants younger than 2 months old or
associated other defects

 Incomplete fusion of the endocardial cushions.
 Consists of a low ASD that is continuous with a high VSD and
clefts of the mitral and tricuspid valves, which create a large
central AV valve that allows blood to flow between all four chambers
of the heart.
 The directions and pathways of flow are determined by
 pulmonary and systemic resistance,
 left and right ventricular pressures, and
 the compliance of each chamber,
 Flow is generally from left to right.
 It is the most common cardiac defect in children with Down

Pathophysiology
The alterations in hemodynamics depend on the severity of
the defect and the child's pulmonary vascular resistance.
Immediately after birth, while the newborn's pulmonary
vascular resistance is high, there is minimum
shunting of blood through the defect.
When this resistance falls, left-to-right shunting
occurs, and pulmonary blood flow increases.
The resultant pulmonary vascular engorgement
predisposes the child to development of HF

 Patients usually have moderate to severe HF.
 There is a loud systolic murmur.
 There may be mild cyanosis that increases with
crying.
 Patients are at high risk for developing
pulmonary vascular obstructive disease

Diagnostic Tests
 On chest radiograph, cardiomegaly and pulmonary
vascular markings are present.
 On ECG, a prolonged PR interval and enlarged
ventricles are noted.
 Echocardiogram reveals dilation of the ventricles,
septal defects, and details of valve malformation.

Surgical treatment:
 Palliative:
 Pulmonary artery banding is occasionally done in
small infants with severe symptoms.
 Complete repair in infancy is most common

 Complete repair:
 Surgical repair consists of patch closure of the
septal defects and reconstruction of the AV valve
tissue (either repair of the mitral valve cleft or
fashioning of two AV valves).
 Postoperative complications include heart block,
HF, mitral regurgitation, dysrhythmias, and
pulmonary hypertension

 Prognosis:
 Operative mortality has been 3% to 10%.
 Factors that increase surgical risk are
 younger age,
 severe AV valve regurgitation,
 hypoplasia of the left ventricle and severe failure
preoperatively, as well as other heart defects
 A potential later problem is mitral regurgitation, which
may require valve replacement.

 Failure of the fetal ductus arteriosus (artery
connecting the aorta and pulmonary artery)
to close within the first weeks of life.
 The continued patency of this vessel allows
blood to flow from the higher pressure aorta to
the lower pressure pulmonary artery, which
causes a left to- right shunt.

Pathophysiolog
y
The hemodynamic consequences of PDA depend on the
size of the ductus and the pulmonary vascular resistance.
At birth, the resistance in the pulmonary and systemic
circulations is almost identical so that the resistance in
the aorta and pulmonary artery is equalized.
As the systemic pressure comes to exceed the
pulmonary pressure, blood begins to shunt from the
aorta across the duct to the pulmonary artery (left-to-
right shunt).
The additional blood is recirculated through the lungs
and returned to the left atrium and left ventricle.
The effects of this altered circulation are increased
workload on the left side of the heart, increased
pulmonary vascular congestion and possibly
resistance, and potentially increased right
ventricular pressure and hypertrophy

 Patients may be asymptomatic or show signs of HF.
 There is a characteristic machinery-like murmur.
 A widened pulse pressure and bounding pulses
result from runoff of blood from the aorta to the
pulmonary artery.
 Patients are at risk for BE and pulmonary vascular
obstructive disease in later life from chronic
excessive pulmonary blood flow.

Diagnostic Tests
 The chest radiograph and ECG show left
ventricular hypertrophy.
 The PDA can be visualized, and PDA blood flow
can be measured onechocardiogram.

Medical management
 Administration of indomethacin (a
prostaglandin inhibitor) has proved successful
in closing a PDA in preterm infants and some
newborns

Surgical treatment
 Surgical division or ligation of the patent vessel
is performed via a left thoracotomy.
 In a newer technique, video-assisted
thoracoscopic surgery, a thoracoscope and
instruments are inserted through three small
incisions on the left side of the chest to place a clip
on the ductus.
 The technique is used in some centers and
eliminates the need for a thoracotomy, thereby
speeding postoperative recovery

 Coils to occlude the PDA are placed in the
catheterization laboratory in many centers.
 Preterm or small infants (with small-diameter
femoral arteries) and patients with large or
unusual PDAs may require surgery

 Prognosis:
 Both surgical procedures can be done at low risk with
zero percent mortality.
 PDA closure in very preterm infants has a higher
mortality rate because of the additional significant
medical problems.
 Complications are rare, but can include injury to the
laryngeal nerve, paralysis of the left hemidiaphragm, or
injury to the thoracic duct.

 Obstructive defects are those in which blood
exiting the heart meets an area of anatomic
narrowing (stenosis), causing obstruction to
blood flow
 The pressure in the ventricle and in the great
artery before the obstruction is increased, and
the pressure in the area beyond the obstruction
is decreased

Valvular: At the site of the valve itself
Subvalvular: Narrowing in the ventricle below the valve (also
referred to as the ventricular outflow tract)
Supravalvular: Narrowing in the great artery above the valve

 Coarctation of the aorta (narrowing of the aortic
arch)
 Aortic stenosis
 Pulmonic stenosis

 Hemodynamic changes
 Pressure load on the ventricle and decreased
cardiac output
 Infants and children exhibit signs of HF

 Localized narrowing near the insertion of the
ductus arteriosus, which results in increased
pressure proximal to the defect (head and upper
extremities) and decreased pressure distal to the
obstruction (body and lower extremities).
 Pathophysiology:
 The effect of a narrowing within the aorta is increased
pressure proximal to the defect (upper extremities) and
decreased pressure distal to it (lower extremities).

 The patient may have high BP and bounding pulses in the arms,
weak or absent femoral pulses, and cool lower extremities with
lower BP.
 Signs of HF in infants.
 In infants with critical coarctation, the hemodynamic condition may
deteriorate rapidly with severe acidosis and hypotension.
 Mechanical ventilation and inotropic support are often necessary before
surgery.
 Older children may experience dizziness, headaches, fainting, and
epistaxis resulting from hypertension.
 Patients are at risk for hypertension, ruptured aorta, aortic

Diagnostic Tests
 The chest radiograph may reveal cardiomegaly,
pulmonary venous congestion,and indentation of the
descending aorta.
 Dilation of the ascendingaorta may be seen.
 Rib notching is rarely seen before 5 years of age.
 MRI is preferred for imaging to see the aortic arch, site of
coarctation, and collateral circulation.
 ECG may be normal or show left ventricular hypertrophy.
 Echocardiogram shows the size of the aorta and
functioning of the aorticvalve and left ventricle.

Surgical treatment
 Surgical repair is the treatment of choice for infants younger than 6
months old and for patients with long-segment stenosis or complex
anatomy; it may be performed for all patients with coarctation.
 Repair is by resection of the coarcted portion with an
end-to-end anastomosis of the aorta or enlargement of
the constricted section using a graft of prosthetic
material or a portion of the left subclavian artery.
 Because this defect is outside the heart an pericardium,
cardiopulmonary bypass is not required, and a thoracotomy incision is
used.

 Postoperative hypertension is treated with IV sodium nitroprusside,
esmolol, or milrinone followed by oral medications, such as ACE
inhibitors or beta-blockers.
 Residual permanent hypertension after repair of COA seems to be
related to age and time of repair.
 To prevent both hypertension at rest and exercise-provoked systemic
hypertension after repair, elective surgery for COA is advised
within the first 2 years of life.
 There is a 15% to 30% risk of recurrence in patients who underwent
surgical repair as infants
 Percutaneous balloon angioplasty techniques have proved to be
effective in relieving residual postoperative coarctation

 Balloon angioplasty is being performed as a
primary intervention for COA in older infants and
children, Balloon angioplasty has a higher associated
rate of recoarctation than surgical repair and the rate
of complication, particularly femoral artery injury is
high during infancy.’
 Prognosis: Mortality is less than 5% in patients with
isolated coarctation; the risk is increased in infants
with other complex cardiac defects

 Narrowing or stricture of the aortic valve, causing
resistance to blood flow in the left ventricle,
decreased cardiac output, left ventricular
hypertrophy, and pulmonary vascular congestion.
 The prominent anatomic consequence of AS is the
hypertrophy of the left ventricular wall, which
eventually leads to increased end-diastolic pressure,
resulting in pulmonary venous and pulmonary arterial
hypertension.

 Left ventricular hypertrophy also interferes with coronary artery perfusion and may
result in myocardial infarction or scarring of the papillary muscles of the left
ventricle, which causes mitral insufficiency.
 Valvular stenosis, the most common type, is usually caused by malformed cusps that
result in a bicuspid rather than tricuspid valve or fusion of the cusps.
 Subvalvular stenosis is a stricture caused by a fibrous ring below a normal valve;
 Supravalvular stenosis occurs infrequently
 Valvular AS is a serious defect for the following reasons:
(1) the obstruction tends to be progressive;
(2) sudden episodes of myocardial ischemia, or low cardiac output, can result in
sudden death;
(3) surgical repair rarely results in a normal valve.
This is one of the rare instances in which strenuous physical activity may be curtailed

A stricture in the aortic outflow tract
Causes resistance to ejection of blood from the left ventricle.
The extra workload on the left ventricle causes hypertrophy.
If left ventricular failure develops, left atrial pressure will increase;
this causes increased pressure in the pulmonary veins, which
results in pulmonary vascular congestion (pulmonary edema).
Pathophysiolo
gy

 Newborns with critical AS demonstrate signs of
decreased cardiac output with faint pulses,
hypotension, tachycardia, and poor feeding.
 Children show signs of exercise intolerance, chest
pain, and dizziness when standing for a long period.
 A systolic ejection murmur may or may not be
present.
 Patients are at risk for BE, coronary insufficiency,
and ventricular dysfunction

Diagnostic Tests
 The chest radiograph may reveal a normal-sized
heart, but a dilated ascending aorta may be seen.
 The ECG may show mild left ventricular hypertrophy
in severe AS.
 An echocardiogram reveals the number of valve
leaflets, pressure gradient across the valve, and size
of the aorta.
 Exercise testing may be used in asymptomatic
children to determine the amount of obstruction
present.

Valvular Aortic Stenosis
treatment
 Surgical treatment:
 Aortic valvotomy is performed under inflow occlusion.
 Used rarely because balloon dilation in the catheterization laboratory is
the first-line procedure.
 Newborns with critical AS and small left-sided structures may
undergo a stage 1 Norwood procedure.
 Prognosis:
 Aortic valve replacement offers a good treatment option and may
lead to normalization of left ventricular size and function

 Aortic valvotomy remains a palliative procedure, and
approximately 25% of patients require additional surgery
within 10 years for recurrent stenosis
 A valve replacement may be required at the second
procedure.
 An aortic homograft with a valve may also be used (extended
aortic root replacement), or the pulmonary valve may be
moved to the aortic position and replaced with a homograft
valve (Ross procedure).

Valvular Aortic Stenosis
treatment
 Nonsurgical treatment:
 The narrowed valve is dilated using balloon angioplasty in the
catheterization laboratory.
 This procedure is usually the first intervention
 Prognosis:
 Complications include aortic insufficiency or valvular
regurgitation, tearing of the valve leaflets, and loss of pulse in
the catheterized limb

Subvalvular Aortic Stenosis
treatment
 Surgical treatment:
 Procedure may involve incising a membrane if one exists or
cutting the fibromuscular ring.
 If the obstruction results from narrowing of the left ventricular
outflow tract and a small aortic valve annulus, a patch may be
required to enlarge the entire left ventricular outflow tract and
annulus and replace the aortic valve; this is known as the
Konno procedure.
 Prognosis:
 Mortality from surgical repairs of subvalvular AS is less than
5%
 About 20% of these patients will develop recurrent subaortic

 Narrowing at the entrance to the pulmonary
artery.
 Resistance to blood flow causes right ventricular
hypertrophy and decreased pulmonary blood
flow.
 Pulmonary atresia is the extreme form of PS in
that there is total fusion of the commissures and
no blood flows to the lungs.

Pathophysiology
When PS is present, resistance to blood flow causes right
ventricular hypertrophy.
If right ventricular failure develops, right atrial pressure will
increase, and this may result in reopening of the foramen
ovale, shunting of unoxygenated blood into the left atrium, and
systemic cyanosis.
If PS is severe, HF occurs, and systemic venous engorgement will
be noted.
An associated defect such as a PDA partially compensates for the
obstruction by shunting blood from the aorta to the pulmonary artery
and into the lungs.

 Patients may be asymptomatic; some have mild cyanosis or
HF.
 Progressive narrowing causes increased symptoms.
 Newborns with severe narrowing are cyanotic.
 A loud systolic ejection murmur at the upper left sternal border
may be present.
 However, in severely ill patients, the murmur may be much
softer because of decreased cardiac output and shunting of
blood.
 Cardiomegaly is evident on chest radiography.
 Patients are at risk for BE

Diagnostic Tests
 The chest radiograph may show an enlarged pulmonary
artery with normal heart size and normal pulmonary
vascularity.
 The ECG may show right atrial enlargement and right
ventricularhypertrophy.
 An echocardiogram provides information about the
thickness of the valve, the pressure gradient across the
valve, and size of the valve ring.
 Cardiac catheterization findings include increased right
ventricular pressure and a normal or slightly lowered
pulmonary artery pressure.

Surgical treatment
 In infants, transventricular (closed) valvotomy
(Brock procedure) is the surgical treatment.
 In children, pulmonary valvotomy with CPB is
the surgical treatment.
 Need for surgical treatment is rare with
widespread use of balloon angioplasty
techniques.
CPB: cardiopulmonary bypass

 Balloon angioplasty in the cardiac catheterization
laboratory to dilate the valve.
 A catheter is inserted across the stenotic pulmonic valve
into the pulmonary artery, and a balloon at the end of the
catheter is inflated and rapidly passed through the
narrowed opening
 The procedure is associated with few complications and
has proved to be highly effective.
 It is the treatment of choice for discrete PS in most
centers and can be done safely in neonates

Defects with Decreased Pulmonary
Blood Flow

 Obstruction of pulmonary blood flow and an anatomic defect (ASD
or VSD) between the right and left sides of the heart because blood
has difficulty exiting the right side of the heart via the pulmonary
artery, pressure on the right side increases, exceeding left-sided
pressure.
 This allows desaturated blood to shunt right to left, causing
desaturation in the left side of the heart and in the systemic
circulation.
 Clinically, these patients have hypoxemia and usually appear
cyanotic.
 Tetralogy of fallot

 The classic form includes four defects:
 VSD,
 PS
 Overriding aorta (aorta is positioned directly over a
ventricular septal defect (VSD), instead of over the left
ventricle)
 Right ventricular hypertrophy.
 Tetralogy of Fallot occurs in 5% to 10% of all CHDs
and is the most common cyanotic lesion

Pathophysiology
 The alteration in hemodynamics varies widely,
depending primarily on the degree of PS but also on
the size of the VSD and the pulmonary and systemic
resistance to flow.
 Because the VSD is usually large, pressures may be
equal in the right and left ventricles.
 Therefore, the shunt direction depends on the
difference between pulmonary and systemic vascular
resistance.

If systemic
resistance is higher
than pulmonary
resistance, the shunt
is from left to right.
If pulmonary vascular
resistance is higher
than systemic
resistance, the shunt
is from right to left

 PS decreases blood flow to the lungs and
consequently the amount of oxygenated blood
that returns to the left side of the heart.
 Depending on the position of the aorta, blood
from both ventricles may be distributed
systemically

 Some infants may be acutely cyanotic at birth; others have
mild cyanosis that progresses over the first year of life as the
PS worsens.
 There is a characteristic systolic murmur that is often
moderate in intensity.
 There may be acute episodes of cyanosis and hypoxia, called
blue spells or tet spells.
 Anoxic spells occur when the infant's oxygen requirements
exceed the blood supply, usually during crying or after feeding.
 Patients are at risk for emboli, seizures, and loss of
consciousness or sudden death after an anoxic spell.

 The newborn becomes hypoxic and cyanotic as the ductus
arteriosus closes.
 The degree of pulmonary stenosis determines severity of
symptoms.
 Older infants and children have tachypnea and cyanosis.
 Polycythemia, hypoxic spells, metabolic acidosis, poor growth,
clubbing, and exercise intolerance may develop.
 Toddlers with uncorrected defects instinctively squat (assume a
knee–chest position) to decrease the return of systemic venous
blood to the heart.
 A systolic murmur is heard in the pulmonic area and transmitted
to the suprasternal notch. A thrill may be palpated in the pulmonic
area

Diagnostic Tests
 A chest radiograph shows the boot-shaped heart due to the
large right ventricle, decreased pulmonary vascular markings,
and a prominent aorta.
 The ECG shows right ventricular hypertrophy.
 The echocardiogram shows the VSD, obstruction of pulmonary
outflow, an overriding aorta, and the size of the pulmonary
arteries.
 The condition may be detected by fetal echocardiography.
 Blood tests reveal an elevated hematocrit and hemoglobin and
an increased clotting time.
 Iron deficiency may be detected

Surgical treatment
 Palliative shunt:
 In infants who cannot undergo primary repair, a
palliative procedure to increase pulmonary blood
flow and increase oxygen saturation may be
performed.
 The preferred procedure is a modified Blalock-
Taussig shunt operation,

Provides blood flow to the
pulmonary arteries from the left
or right subclavian artery via a
tube graft In general, however,
shunts are avoided because they
may result in pulmonary artery
distortion.

 Complete repair:
 Elective repair is usually performed in the first year of life
 Indications for repair include
 increasing cyanosis and the development of hypercyanotic spells.
 Complete repair involves closure of the VSD and resection of the
infundibular stenosis, with placement of a pericardial patch to
enlarge the RVOT.
 In some repairs, the patch may extend across the pulmonary valve
annulus (transannular patch), making the pulmonary valve
incompetent.
 The procedure requires a median sternotomy and the use of

Prognosis
 The operative mortality for total correction of tetralogy of
Fallot is less than 2% to 3% during the first 2 years of life
 Infants younger than 3 months old and children older
than 4 years old, as well as those with other CHD or
hypoplasia of the pulmonary annulus and trunk have a
higher mortality rate.
 With improved surgical techniques, there is a lower
incidence of dysrhythmias and sudden death; surgical
heart block is rare.
 HF may occur postoperatively

 The tricuspid valve fails to develop; consequently
there is no communication from the right atrium to the
right ventricle.
 Blood flows through an ASD or a patent foramen ovale to
the left side of the heart and through a VSD to the right
ventricle and out to the lungs.
 The condition is often associated with PS and TGA.
 There is complete mixing of unoxygenated and
oxygenated blood in the left side of the heart, which
results in systemic desaturation, and varying amounts
of pulmonary obstruction, which causes decreased
pulmonary blood flow.

Pathophysiology
 At birth, the presence of a patent foramen ovale
(or other atrial septal opening) is required to
permit blood flow across the septum into the left
atrium; the PDA allows blood flow to the
pulmonary artery into the lungs for oxygenation.
 A VSD allows a modest amount of blood to enter
the right ventricle and pulmonary artery for
oxygenation. Pulmonary blood flow usually is
diminished.

 Cyanosis is usually seen in the newborn period.
 There may be tachycardia and dyspnea.
 Older children have signs of chronic hypoxemia
with clubbing.

Diaganostic Tests
 The chest radiograph may reveal a normal size or
slightly enlarged right atrium and left ventricle.
 The ECG may reveal left ventricular hypertrophy.
 The echocardiogram shows a small hypoplastic right
ventricular cavity and tricuspid valve, an absent right
ventricular outflow tract, a dilated right atrium, and
right-to-left shunting across the atrial septum

Therapeutic management
 For neonates whose pulmonary blood flow
depends on the patency of the ductus arteriosus,
a continuous infusion of prostaglandin E1 is
started at 0.1 mcg/kg/min until surgical
intervention can be arranged

Surgical treatment
 Palliative treatment is the placement of a shunt
(pulmonary–to–systemic artery anastomosis) to
increase blood flow to the lungs.
 If the ASD is small, an atrial septostomy is performed
during cardiac catheterization.
 Some children have increased pulmonary blood flow and
require pulmonary artery banding to lessen the volume
of blood to the lungs.
 A bidirectional Glenn shunt (cavopulmonary
anastomosis) may be performed at 4 to 9 months as a
second stage

 Modified Fontan procedure:
 Systemic venous return is directed to the lungs without a ventricular
pump through surgical connections between the right atrium and the
pulmonary artery.
 A fenestration (opening) is sometimes made in the right atrial baffle to
relieve pressure. The patient must have normal ventricular function
and a low pulmonary vascular resistance for the procedure to be
successful.
 The modified Fontan procedure separates oxygenated and
unoxygenated blood inside the heart and eliminates the excess
volume load on the ventricle but does not restore normal anatomy or
hemodynamics.
 This operation is also the final stage in the correction of many
complex defects with a functional single ventricle, including HLHS.

Prognosis
 Surgical mortality following the Fontan procedure is less than 3%
 Theoverall survival rate after the Fontan operation was above 95% at
follow up of 50 months
 Postoperative complications include
 dysrhythmias,
 systemic venous hypertension,
 pleural and pericardial effusions, and
 ventricular dysfunction.
 Long-term concerns are the development of protein-losing
enteropathy, atrial dysrhythmias, late ventricular dysfunction, and
developmental delays.

Many complex cardiac anomalies are classified together in the
mixed category because survival in the postnatal period depends on
mixing of blood from the pulmonary and systemic circulations
within the heart chambers.
 Hemodynamically, fully saturated systemic blood flow mixes with
the desaturated pulmonary blood flow, causing a relative
desaturation of the systemic blood flow
 Pulmonary congestion occurs because the differences in pulmonary
artery pressure and aortic pressure favor pulmonary blood flow.

 Cardiac output decreases because of a volume load on
the ventricle
 Clinically, these patients have a variable picture that
combines some degree of desaturation (although
cyanosis is not always visible) and signs of HF
 Some defects, such as transposition of the great
arteries, cause severe cyanosis in the first days of life
and later cause HF.
 Others, such as truncus arteriosus, cause severe HF in
the first weeks of life and mild desaturation.

 Transposition of the Great Arteries, or
Transposition of the Great Vessels
 Total Anomalous Pulmonary Venous
Connection
 Truncus Arteriosus
 Hypoplastic Left Heart Syndrome

Transposition of the Great Arteries, or
Transposition of the Great Vessels

 The pulmonary artery leaves the left ventricle,
and the aorta exits from the right ventricle with
no communication between the systemic and
pulmonary circulations

Pathophysiology
 Associated defects, such as septal defects or PDA, must be
present to permit blood to enter the systemic circulation or the
pulmonary circulation for mixing of saturated and desaturated
blood.
 The most common defect associated with TGA is a patent
foramen ovale.
 At birth, there is also a PDA, although in most instances, this closes
after the neonatal period.
 Another associated defect may be a VSD.
 The presence of a VSD increases the risk of HF because it permits
blood to flow from the right to the left ventricle, into the pulmonary
artery, and finally to the lungs.
 However, it also produces high pulmonary blood flow under high
pressure, which can result in high pulmonary vascular resistance

 These depend on the type and size of the associated
defects.
 Newborns with minimum communication are
severely cyanotic and have depressed function at
birth.
 Those with large septal defects or a PDA may be
less cyanotic but have symptoms of HF.
 Heart sounds vary according to the type of defect
present.
 Cardiomegaly is usually evident a few weeks after

Diagnostic Tests
 A chest radiograph may reveal a classic egg-shaped
heart on a string with enlarged ventricles and
increased pulmonary vascular markings.
 The ECG reveals right ventricular hypertrophy.
 The echocardiogram often shows the abnormal
position of the great arteries rising from the ventricles
and any associated defects.
 Blood tests reveal an increased hematocrit and
hemoglobin or polycythemia and acidosis.

 To provide intracardiac mixing
 The administration of IV prostaglandin E1 may be
initiated to keep the ductus arteriosus open to
temporarily increase blood mixing and provide an
oxygen saturation of 75% or to maintain cardiac
output.
 During cardiac catheterization or under
echocardiographic guidance, a balloon atrial
septostomy (Rashkind procedure) may also be
performed to increase mixing by opening the atrial
septum.

Surgical treatment
 An arterial switch procedure is the procedure of choice
performed in the first weeks of life.
 It involves transecting the great arteries and anastomosing the
main pulmonary artery to the proximal aorta (just above the aortic
valve) and anastomosing the ascending aorta to the proximal
pulmonary artery.
 The coronary arteries are switched from the proximal aorta to
the proximal pulmonary artery to create a new aorta.
 Reimplantation of the coronary arteries is critical to the infant's
survival, and they must be reattached without torsion or
kinking to provide the heart with its supply of oxygen.

 The advantage of the arterial switch procedure is
the reestablishment of normal circulation, with
the left ventricle acting as the systemic pump.
 Potential complications of the arterial switch
include narrowing at the great artery
anastomoses and coronary artery insufficiency.

Intraatrial baffle repairs:
 Intraatrial baffle repairs are rarely performed,
although many adolescents and adults survive today
with repairs that were done more than 15 years ago.
 An intraatrial baffle is created to divert venous blood
to the mitral valve and pulmonary venous blood to
the tricuspid valve using the patient's atrial septum
(Senning procedure) or a prosthetic material
(Mustard procedure).

 A disadvantage is the continuing role of the right
ventricle as the systemic pump and the late
development of right ventricular failure and
rhythm disturbances.
 Other potential postoperative complications
include loss of normal sinus rhythm, baffle leaks,
and ventricular dysfunction.

Rastelli procedure:
 This procedure is the operative choice in infants with
TGA, VSD, and severe PS.
 It involves closure of the VSD with a baffle so that left
ventricular blood is directed through the VSD into the
aorta.
 The pulmonic valve is then closed, and a conduit is
placed from the right ventricle to the pulmonary artery to
create a physiologically normal circulation.
 Unfortunately, this procedure requires multiple conduit
replacements as the child grows

Prognosis:
 Mortality rate varies dependent upon the
anatomy and procedure performed.
 The operative mortality rate for neonates with
TGA and intact ventricular septum is at 6%
 Potential long-term problems include
 Suprapulmonic stenosis and neoaortic dilation and
regurgitation, as well as coronary artery obstruction.

Total Anomalous Pulmonary Venous
Connection

 Rare defect characterized by failure of the
pulmonary veins to join the left atrium.
 Instead, the. pulmonary veins are abnormally
connected to the right atrium or various veins
draining toward the right atrium, such as the SVC
 The abnormal attachment results in mixed blood
being returned to the right atrium and shunted from
the right to the left through an ASD

 TAPVC (also called total anomalous pulmonary
venous return or total anomalous pulmonary venous
drainage)
 Classification
 Supracardiac: Attachment above the diaphragm,
such as to the SVC (most common form)
 Cardiac: Direct attachment to the heart, such as to
the right atrium or coronary sinus
 Infradiaphragmatic: Attachment below the
diaphragm, such as to the IVC (most severe form)

The right atrium receives all the blood that normally would flow into the left
atrium.
As a result, whereas the right side of the heart hypertrophies, the left side,
especially the left atrium, may remain small.
An associated ASD or patent foramen ovale allows systemic venous blood to
shunt from the higher pressure right atrium to the left atrium and into the left
side of the heart.
As a result, the oxygen saturation of the blood in both sides of the heart (and
ultimately in the systemic arterial circulation) is the same.
Pathophysiolo
gy

If the pulmonary blood flow is large, pulmonary venous return is also large, and
the amount of saturated blood is relatively high.
However, if there is obstruction to pulmonary venous drainage, pulmonary
venous return is impeded, pulmonary venous pressure rises, and pulmonary
interstitial edema develops and eventually contributes to HF.
Infradiaphragmatic TAPVC is often associated with obstruction to pulmonary
venous drainage and is a surgical emergency
Pathophysiolo
gy

 Most infants develop cyanosis early in life.
 The degree of cyanosis is inversely related to the
amount of pulmonary blood flow—the more pulmonary
blood, the less cyanosis.
 Children with unobstructed TAPVC may be
asymptomatic until pulmonary vascular resistance
decreases during infancy, increasing pulmonary blood
flow with resulting signs of HF.
 Cyanosis becomes worse with pulmonary vein
obstruction; when obstruction occurs, the infant‘s
condition usually deteriorates rapidly. Without
intervention, cardiac failure will progress to death.

Diagnostic Tests
 The chest radiograph shows enlargement of the right
atrium and ventricle and increased pulmonary blood
flow.
 The ECG reveals right ventricular hypertrophy.
 The echocardiogram shows a dilated right atrium and
ventricle, smaller left-sided chambers, dilated
pulmonary arteries, and a patent foramen ovale.
 It can determine the type of pulmonary drainage and
if the pulmonary venous return is obstructed

Surgical treatment
 Corrective repair is performed in early infancy. The
surgical approach varies with the anatomic defect.
 In general, however, the common pulmonary vein is
anastomosed to the back of the left atrium, the ASD is
closed, and the anomalous pulmonary venous connection
is ligated.
 The cardiac type is most easily repaired; the
infradiaphragmatic type carries the highest morbidity and
mortality because of the higher incidence of pulmonary vein
obstruction.
 Potential postoperative complications include
 re-obstruction; bleeding; dysrhythmias, particularly heart block;
PAH; and persistent heart failure.

Prognosis:
 Mortality is between 5%
to 10% for infants without
obstruction, and it can be
as high as 20% for infants
with infradiaphragmatic
type.

 Failure of normal septation and division of the
embryonic bulbar trunk into the pulmonary artery
and the aorta, which results in development of a
single vessel that overrides both ventricles.
 Blood from both ventricles mixes in the common
great artery, which leads to desaturation and
hypoxemia.
 Blood ejected from the heart flows preferentially to
the lower pressure pulmonary arteries so that
pulmonary blood flow is increased and systemic
blood flow is reduced.

 There are three types
 Type I: A single pulmonary trunk arises near the base of
the truncus and divides into the left and right pulmonary
arteries.
 Type II: The left and right pulmonary arteries arise
separately but in close proximity and at the same level
from the back of the truncus.
 Type III: The pulmonary arteries arise independently
from the sides of the truncus

Pathophysiolo
gy
Blood ejected from the left
and right ventricles enters
the common trunk so that
pulmonary and systemic
circulations are mixed.
Blood flow is distributed to the
circulations according to the
relative resistances of each
system.
The amount of pulmonary
blood flow depends on the size
of the pulmonary arteries and
the pulmonary vascular
resistance.
Generally, resistance to
pulmonary blood flow is less
than systemic vascular
resistance, which results in
preferential blood flow to the
lungs.
Pulmonary vascular disease
develops at an early age in
patients with truncus arteriosus

 Most infants are symptomatic with moderate to
severe HF and variable cyanosis, poor growth,
and activity intolerance.
 There is a holosystolic murmur at the left sternal
murmur with a diastolic murmur present if truncal
regurgitation is present.
 Thirty-five percent of patients have 22q11
deletions

Diagnostic Tests
 The chest radiograph shows cardiomegaly, increased
pulmonary vascular markings, and sometimes a right
aortic arch.
 The ECG reveals bilateral ventricular hypertrophy.
 The echocardiogram shows a VSD, a large single
great artery, and one semilunar valve

Surgical treatment:
 Early repair is performed in the first month of life.
 It involves closing the VSD so that the truncus
arteriosus receives the outflow from the left ventricle and
excising the pulmonary arteries from the aorta and
attaching them to the right ventricle by means of a
homograft.
 Currently, homografts (segments of cadaver aorta and
pulmonary artery that are treated with antibiotics and
cryopreserved) are preferred over synthetic conduits to
establish continuity between the right ventricle and
pulmonary artery.

 Homografts are more flexible and easier to use during the procedure and
appear less prone to obstruction.
 Postoperative complications include
 Persistent heart failure,
 Bleeding,
 PAH,
 Dysrhythmias, and
 Residual VSD.
 Because conduits are not living tissue, they will not grow along with the child
and may also become narrowed with calcifications.
 One or more conduit replacements will be needed in childhood
 Prognosis: Mortality is greater than 10%; future operations are required to
replace the conduits

Hypoplastic Left Heart
Syndrome

 Underdevelopment of the left side of the
heart, resulting in a hypoplastic left ventricle
and aortic atresia.
 Most blood from the left atrium flows across the
patent foramen ovale to the right atrium, to the
right ventricle, and out the pulmonary artery.
 The descending aorta receives blood from the
PDA supplying systemic blood flow

Pathophysiolo
gy An ASD or patent foramen ovale
allows saturated blood from the left
atrium to mix with desaturated blood
from the right atrium and to flow
through the right ventricle and out
into the pulmonary artery.
From the pulmonary artery,
the blood flows both to the
lungs and through the
ductus arteriosus into the
aorta and out to the body.
The amount of blood flow to
the pulmonary and systemic
circulations depends on the
relationship between the
vascular resistances.
The coronary and cerebral vessels receive blood by
retrograde flow through the hypoplastic ascending
aorta.

 The patient has mild cyanosis and signs of HF
until the PDA closes and then progressive
deterioration with cyanosis and decreased
cardiac output, leading to cardiovascular
collapse.
 The condition is usually fatal in the first months
of life without intervention

Diagnostic Procedures
 The chest radiograph shows cardiomegaly and
increased pulmonary venous congestion.
 The ECG shows right ventricular hypertrophy.
 The echocardiogram shows the small left ventricle and
enlarged right ventricle.
 This condition is often diagnosed prenatally

 Neonates require stabilization with
mechanical ventilation and inotropic support
preoperatively.
 A prostaglandin E1 infusion is needed to
maintain ductal patency and ensure adequate
systemic blood flow.

Surgical treatment:
 A multiple-stage approach is used.
 The first stage is a Norwood procedure, which involves an anastomosis of
the main pulmonary artery to the aorta to create a new aorta, shunting to
provide pulmonary blood flow (usually with a modified Blalock-Taussig
shunt), and creation of a large ASD.
 Postoperative complications include
 Imbalance of systemic and pulmonary blood flow,
 bleeding,
 low cardiac output, and
 persistent heart failure.
 A new modification of the first stage repair is the use of a right ventricle–to–
pulmonary artery homograft conduit instead of a shunt to supply pulmonary
blood flow (Sano procedure).

 The second stage is often a bidirectional Glenn
shunt procedure or a hemi-Fontan operation.
 Both involve anastomosing the SVC to the right
pulmonary artery so that SVC flow bypasses the right
atrium and flows directly to the lungs.
 The procedure is usually done at 3 to 6 months of
age to relieve cyanosis and reduce the volume load
on the right ventricle.
 The final repair is a modified Fontan procedure

Transplantation
 Heart transplantation in the newborn period is
another option for these infants.
 Problems include the
 shortage of newborn organ donors,
 risk of rejection,
 long-term problems with chronic
immunosuppression,
 and infection

Prognosis:
 For the first-stage repair, survival rates vary widely in different
centers.
 Much progress has been made, and some experienced centers
are reporting mortality rates of about 10%
 Long-term problems with repair include
 Worsening ventricular function,
 tricuspid regurgitation,
 recurrent aortic arch narrowing,
 dysrhythmias, and developmental delays.
 There is a risk of mortality between surgical procedures.
 The mortality for the later two operations is less than 5%

Additional points
 Eisenmenger syndrome
 Eisenmenger syndrome is a condition that results from
abnormal blood circulation caused by a defect in the heart.
 The defect (hole) allows blood that has already picked up
oxygen from the lungs to flow back into the lungs, instead of
going out to the rest of the body.
 Eisenmenger syndrome may begin to develop before a child
reaches puberty. However, it also can develop in young
adulthood, and may progress throughout young adulthood.

 Other heart defects that can lead to
Eisenmenger syndrome include:
 Atrioventricular canal defect
 Atrial septal defect
 Cyanotic heart disease
 Patent ductus arteriosus
 Truncus arteriosus

Increased blood flow can damage the small blood vessels in the
lungs.
This causes high blood pressure in the lungs.
As a result, the blood flow goes backward through the hole between
the two pumping chambers.
This allows oxygen-poor blood to travel to the rest of the body.

Congenital heart diseases

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