Title: Congenital Heart Disease
1Congenital Heart Disease 1 2005
Susan Etheridge, MD
2Congenital Heart Disease
- Objectives
- Recognize that children can be born with heart
problems - Recognize that heart disease in children has
signs and symptoms that are different from adults - Identify congenital cardiac defects, presenting
signs and symptoms - Application of general principles of cardiac
physiology and pathophysiology to specific
congenital heart lesions
3Congenital Heart Disease (CHD)
- Congenital - condition that is present at birth
- 8-10/1000 live births
- Increasing survival of children with CHD
600,000 adults in US with CHD - Increasingly diagnosed in utero - may affect
maternal management - Increasing complexity of the diagnoses of
survivors
4Risks in Adults with CHD
- Stroke
- Endocarditis
- Heart failure
- Pulmonary hypertension
- Pregnancy complications
- Arrhythmias (atrial fibrillation, atrial
reentrant tachycardia, ventricular tachycardia,
ventricular fibrillation) - Sinus node and AV node disease
- Sudden death
5Congenital Heart Disease Etiology
- Multifactoral (most common)
- Single gene mutations
- Chromosome abnormalities
- Environmental factors (alcohol, lithium)
DiGeorge 22q11
Trisomy 13
Trisomy 18
Trisomy 21
6Classification
- Chamber identity not be based on position
- Chamber, vessel, valve can be anywhere
- left ventricle can be on the right
- Morphologic features of the chambers
- and valves identify them
- right ventricle heavily trabeculated
- left ventricle smooth-walled
- AV valves go with respective ventricles
- the valve that empties into left ventricle is
mitral valve
7Congenital Heart Disease
- May result in
- no symptoms
- heart failure
- cyanosis
8Heart Failure
- Heart unable to pump sufficient blood to meet
metabolic demands of body - Excessive work load on the heart
- normal myocardium
- volume load
- pressure load
- example congenital heart disease
- Normal workload faced by damaged or abnormal
myocardium - example myocarditis
9Heart Failure Signs and Symptoms
- due to
- low cardiac output
- systemic adaptation to low cardiac output
- systemic and/or pulmonary venous congestion
10Signs and Symptoms
- Age-dependent
- Fetus Hydrops
- Infants
- poor feeding, sweating with feeding, tachypnea,
tachycardia, cool extremities, diminished pulses,
mottling, hepatomegaly - Children (similar to adults)
- exertional dyspnea, orthopnea, chronic cough,
hepatomegaly, neck vein distention, peripheral
edema
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12Cyanosis and Hypoxemia
- Hypoxemia - arterial saturation lt 90 in room air
- respiratory causes (example pneumonia)
- cardiac causes - shunting of blood from a right
heart structure to a left heart structure
(right-to-left shunt) - Cyanosis - bluish discoloration of skin
- perceptible when gt 5 gm/dl of reduced hemoglobin
in the capillaries
13Infant with cyanosis
14Cyanosis and Hypoxemia associated problems
- Clubbing - widening and thickening of distal
digits - occurs with hypoxemia
- due to increased capillaries and increased blood
flow through multiple arteriovenous aneurysms - increased connective tissue in terminal phalanges
15Cyanosis and clubbing in a child with Tetralogy
of Fallot
16Cyanosis and Hypoxemia associated problems
- Polycythemia - increased total RBC in blood
- low arterial O2 content acts via renal
erythropoietin - stimulates bone marrow to
increase RBC production increased O2 carrying
capacity and O2 delivery - useful compensatory mechanism until hematocrit
70-80 when blood becomes too viscous
17Cyanosis and Hypoxemia associated problems
- Squatting - posture assumed after exertion in
children with some cyanotic congenital heart
diseases - gt 1 - 2 year olds
- increases O2 saturation by increasing venous
return - increases peripheral resistance - decreases right
to left shunt - not seen recently due to earlier repair of
cyanotic infant
- Other exercise intolerance, increased risk of
brain abscesses and strokes
18Classification of Congenital Heart Disease
19Left to Right Shunt Lesions
- Abnormal shunting of blood from systemic
circulation to pulmonary circulation - Oxygenated blood returns to lungs - increases
pulmonary blood flow - Ventricular Septal Defects, Atrial Septal
Defects, Patent Ductus Arteriosus,
Atrioventricular septal defect, Aorticopulmonary
window
20Ventricular Septal Defect (VSD)
- Defect (hole) in a portion of septum that
separates right and left ventricle - Most common congenital cardiac lesion
- Location
- perimembranous septum
- muscular septum
- inlet septum (AV canal type)
- subarterial septum
21Perimembranous VSD
Muscular VSD
22Ventricular Septal Defect (VSD)
- Defect size more important than location
- Small to medium sized defects smaller size
restricts amount of left to right shunting - Large defect nonrestrictive, no resistance to
flow across the defect - Shunt direction and volume determined by relative
resistances of systemic and pulmonary circuits
23VSD Pathophysiology
- Oxygenated blood crosses LV to RV
- Red blood from LV mixes with blue blood in RV
(therefore no cyanosis) - Increased blood in RV (well-tolerated)
- Increased blood in pulmonary arterial circuit
- Increased blood returning to left atrium (LA) and
LV volume overload and LV- enlargement
24Pathophysiology Large VSD
- Magnitude and direction of shunt determined by
relative resistances of systemic and pulmonary
circuits - Usually LgtR
- SVR - higher resistance - systemic arterioles
have thick muscular wall, narrow lumen - PVR- lower resistance - pulmonary arterioles have
a thin wall, wide lumen - Reflected by higher aortic pressure compared to
pulmonary artery pressure and hence higher LV
pressure than RV pressure
25Pathophysiology Large VSD
Red blood crosses from LV to RV through
VSD Large defect allows equalization of LV and
RV pressures Increased blood in pulmonary
circuit Increased pressure and O2 saturation in
pulmonary artery
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LV
99
92/6
RV
26Pathophysiology Large VSD
Increased LA volume - increased blood returning
to the LA from the pulmonary circuit Increased
blood in the LV - LVE Increased LV radius -
myocardial fibers lengthen Significant LV
dilation - myocardium cannot develop sufficient
tension to maintain pressure Heart Failure
27Large VSD
- Two hemodynamic loads
- Equalization of RV and LV pressure -Pressure load
on - RV - Increased blood passes across the VSD into - RV
and subsequently into pulmonary circuit Increased
blood then returns to LA and LV - Volume load on
the LV - This results in heart failure
28Large VSD
- Try to imagine situations where a large VSD may
shunt in the right to left direction keeping in
mind the PVR and SVR relationship
29Development of Heart Failure with Large VSD
- LV volume overload (increased preload)
- ? LV dilation
- ? increased LV radius (R)
- ? as LV radius increases LV tension (T) must
increase to maintain pressure (P) (LaPlace
relationship T P X R) - ? continued LV dilation
- ? myocardium cannot develop sufficient tension to
maintain pressure/volume relationship - ? Heart Failure
30Large VSD and Heart Failure
- Compensatory mechanisms to maintain myocardial
performance and cardiac output - Stimulation of sympathetic nervous system
-increased catecholamine release - ? increased force of contraction
- ? increased heart rate
-
- myocardial hypertrophy
31Effects of Large VSD and CHF
- decreased EF
- increased residual volume in LV after contraction
- increased LV EDP (end diastolic pressure)
- increased LA pressure
- increased pulmonary venous pressure
- increased alveoli fluid
- poor gas exchange
32Clinical Picture
- History
- Symptoms of heart failure often 2 - 3 months of
age - tachypnea (rapid breathing)
- increased work of breathing
- poor feeding
- diaphoresis (sweating) with feedings
- recurrent respiratory infections
33Clinical Picture
- Why are there so many pulmonary symptoms in
children with a large VSD? - Why are the children tachycardic and diaphoretic
(sweaty)?
34Clinical Picture
- Examination
- murmur - noise made by turbulent blood crossing
hole in the ventricular septum - high frequency
holosystolic murmur - heart sounds increased second heart sound (S2)
due to increased pulmonary artery pressure - cardiac enlargement (left chest enlargement)
- signs of failure - tachycardia, tachypnea,
dyspnea, retractions, growth failure,
hepatomegaly
35Clinical Picture
- CXR
- usually normal at birth
- cardiac enlargement develops with time
- LA and LV enlargement
- increased pulmonary blood flow (increased size of
the pulmonary vessels)
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37RV
LV
Echocardiogram of a large VSD
38Clinical Picture
- Management
- anticongestive medications
- diuretics
- afterload reduction
- digoxin
- surgical closure
- Large defects do not close spontaneously
39Large VSD Question
- You have been following a 2-month-old with a
large VSD. - She is lost to follow-up and returns to clinic at
age 8 years. - On examination, she no longer has the signs and
symptoms of a left -to-right shunt. - Should you be pleased because the large VSD has
closed spontaneously? - What happens to the pulmonary vasculature
exposed to increased blood flow and systemic
pressures for a long time?
40Small VSD
Small VSD pressure restrictive - does not allow
equalization of LV and RV pressures Shunt is
left to right because LV systolic pressure
greater than RV systolic pressure pressure
restrictive Normal pulmonary artery pressures L
gt R shunt is small
41Small VSD Clinical Picture
- History
- usually asymptomatic, no heart failure
- murmur typically at first newborn outpatient
evaluation - murmur usually not present at birth because of
high pulmonary resistance at birth and high RV
pressures therefore little shunting of blood
across VSD - even small VSDs often have very loud murmurs
42Small VSD Clinical Picture
- Examination
- usually no heart failure symptoms or cardiomegaly
- often a loud murmur
- Natural history/management
- many become smaller or close spontaneously
- 50 of perimembranous get smaller or close,
usually within 6 months - 1 year - muscular defects commonly close especially in
infants
43Patent Ductus Arteriosus (PDA)
- Persistence of fetal communication between the
aorta and pulmonary artery - should close by 1st day of life
- embryonic left 6th arch
- More common in premature infants
- Direction and magnitude of shunt through the PDA
depends on relative SVR and PVR
44LPA
RPA
Constricting PDA
Aorta
Main PA
RVOT
45Large PDA
- Aortic pressure pulmonary artery pressure
(large defect allows equalization of pressures) - But systemic resistance remains higher than
pulmonary resistance (SVR gt PVR) - L gt R shunt
46Hemodynamics of Large PDA
Shunting of red blood from the aorta to pulmonary
artery Increased pulmonary blood flow Increased
pulmonary artery pressure and increased O2
saturation in pulmonary artery
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103/40
99
47Hemodynamics Large PDA
- Low diastolic blood pressure
- run-off into pulmonary artery (PA)
- Increased blood in pulmonary circuit
- increased blood returning to LA
- increased LA pressure
- Poor gas exchange
- low O2 sat in pulmonary veins and LA
- Increased blood in LV results in
- LV enlargement and increased
- LVEDP
Heart Failure
48Clinical Picture Large PDA
- History
- More common in females (21)
- Associated with maternal rubella, high altitude,
Down syndrome, prematurity - Present with asymptomatic murmur within days to
weeks of birth - Large PDA heart failure symptoms (similar to
VSD)
49Clinical Picture - Large PDA
- Examination
- murmur noise made from continuous shunting of
turbulent blood from aorta to PA - classic murmur - continuous machinery murmur
- wide pulse pressure
- low diastolic blood pressure
- due to run-off of blood from Aorta to Pulmonary
artery - bounding pulses-due to large difference btw
systolic and diastolic pressure
50Clinical Picture - Large PDA
- CXR
- increased pulmonary blood flow
- cardiac enlargement
- prominent aortic and pulmonary trunks
- small PDA - normal CXR
51Clinical Picture - Large PDA
- Catheterization - only if planning coil occlusion
- Management
- ligation CHF
- some small PDAs close spontaneously but usually
not after age 1 year - ligation of large or moderate PDA to prevent
pulmonary vascular disease or CHF - PDAs (even tiny PDA) are usually closed (after
age 1 year or so) to prevent endocarditis
(infection of the heart) - risk 0.45 per year
52Ligation of PDA
53Large PDA Coil Occlusion
54Atrial Septal Defect (ASD)
- Defect (hole) in septum btw the right and left
atrium - usually in region of fossa ovalis
- may be single or multiple
- Location
- Secundum (fossa ovalis) - most common
- Sinus venosus (near SVC/RA junction) may be
associated with anomalous venous drainage - Primum defect AV canal type defect
- Location important because of associated defects
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57ASD Locations
- a. secundum
-
- b. sinus venosus
- c. primum
-
b
a
c
58Hemodynamics ASD
- Amount of shunt depends on relative RV and LV
compliance not size or location of defect - RV more compliant than LV - direction of shunt is
from least compliant toward the most compliant
chamber - L gt R shunt - red blood from LA crosses ASD into
right atrium (RA) - no cyanosis (acyanotic)
59ASD in the Neonate
- Neonates have decreased RV compliance immediately
after birth - less L gt R shunt at birth
- may even be R gt L shunt - cyanosis
- RV compliance increases with age and L gt R shunt
increases
60Hemodynamics ASD
Red blood crosses from LA to RA Increased O2
saturation in RA and increased RA
volume Increased O2 saturation in RV and
increased RV volume Increased blood in pulmonary
circuit - normal PA pressures and resistance
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93
61Clinical Picture ASD
- History
- more common in females
- cyanosis occurs (rarely) in neonates due to R gt L
shunt due to decreased RV compliance - usually diagnosed in preschool and school aged
children with a murmur - usually asymptomatic
- heart failure and growth failure rare in children
62Clinical Picture ASD
- Adult unrepaired ASD patients
- pulmonary vascular disease (gt 20 years) more
common in females - atrial arrhythmias (atrial fibrillation, atrial
flutter)
63Clinical Picture ASD
- Examination
- RV precordial bulge (due to enlarged RV)
- murmur- systolic ejection murmur due to increased
blood flow across the pulmonary valve - murmur is not due shunting across the ASD, this
is a low velocity shunt and does not make noise
64Clinical Picture ASD
- S2 (second heart sound) widely split - due to
delayed emptying of volume-overloaded RV - fixed split - due to unlimited communication
between the 2 atria - ASD allows for equalization of the influence of
respiratory variation on RV and LV output
65Clinical Picture ASD
- CXR
- increased pulmonary blood flow
- prominent right heart border due to enlargement
of RA and RV
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68Natural History and Management
- surgical / device closure at 3 - 5 years if L gt
R shunting is proven (rarely close spontaneously
after age 3 years) - prevents development of pulmonary vascular
disease, late rhythm problems (atrial
tachycardia) - unrepaired ASDs result in pulmonary vascular
disease in 5 - 10 of patients - unrepaired there is a risk of paradoxical emboli
stroke
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70Septal occluder in position
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72ASD Question
- A 45 year- old woman with known pulmonary
hypertension due to sarcoidosis. - She presents with a stroke and is noted to have
an ASD on an echocardiogram. - Why did the neurologists order an echocardiogram?
- Why did she not have a murmur or widely split
second heart sound? What might you notice on
physical exam?
73ASD in a woman with pulmonary hypertension
74Obstructive Lesions - Basic Hemodynamic
Principles
- outflow obstruction more common than inflow
- elevated pressure proximal to obstruction leads
to hypertrophy of chamber proximal to obstruction - smaller orifice greater pressure needed to
deliver cardiac output beyond obstruction - cardiac output is maintained
- signs and symptoms are due to pressure elevation
proximal to obstruction and to chamber
hypertrophy
75Obstructive Lesions
- Obstruction leads to
- hypertrophy
- hypertrophy results in increased O2 demand
- fibrosis results if there is inadequate O2 to
meet demands - fibrosis leads to chamber dilation
- Heart failure
76Coarctation of the Aorta
- narrowing of descending Aorta
- usually discrete area of stenosis
- juxtaductal - opposite the site where the ductus
arteriosus entered) - intimal thickening and medial ridges that
protrude posteriorly and laterally into the
aortic lumen
77Monosomy X - Turner syndrome
- Occurs ins 1/2,500 females
- High miscarriage rate
- Clinical features
- Lymphedema
- Webbed neck
- Short stature
78Coarctation Pathology
79Coarctation
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81Coarctation of the Aorta
- Upper extremity hypertension
- Upper extremity blood pressure gtgt lower extremity
blood pressure - Associated bicuspid aortic valve in approx. 50
82Hemodynamics of Coarctation
mechanical obstruction pressure elevation
proximal to obstruction decreased pressure
distal to obstruction
83Hemodynamics of Coarctation
Collaterals (internal mammaries, intercostals)
to bypass the obstruction LV hypertrophy
helps maintain wall stress systolic function
normal LV EF LV diastolic function may
not be normal due to decreased compliance of
hypertrophied LV
84Clinical Picture Coarctation
- History
- M gt F (in females consider Turner syndrome)
- 10 present in infancy with CHF
- may be life-threatening in infancy usually
requiring immediate and aggressive treatment - older children present with hypertension,
decreased lower extremity pulses, murmur,
claudication (leg pain with walking), and
headaches
85Clinical Picture - Examination
- normal growth and development in children out of
newborn period - neonates may present with severe CHF, low
cardiac output, shock - children upper extremity blood pressure at least
20 mmHg greater than lower extremity blood
pressure - decreased femoral pulses with pulse delay (lower
extremity pulse later than upper extremity pulse)
86Clinical Picture - Examination
- murmur- systolic ejection murmur best heard
between scapulae, left sternal border, apex, - extends into diastole
- turbulent blood crossing the coarctation site
87CXR - Coarctation
neonate/infant cardiac enlargement, pulmonary
edema, pulmonary venous congestion
88CXR - Coarctation
children normal heart size rib notching
dilation of descending aorta 3 sign
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91Angiogram - Coarcation
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96Coarctation - Natural History and Management
- Neonates with decreased cardiac output -
emergency - Prostaglandin E to maintain PDA patency until
surgery- allows blood to bypass coarctation to
promote perfusion of the organs supplied by the
descending aorta - Surgical repair once medically stabilized
97Coarct
PDA
Aorta
Pulmonary Artery
98Coarctation - Natural History and Management
- Children
- if hypertensive
- significant UE - LE gradient, LV hypertrophy
surgical repair - Recoarctation may occur after repair, increased
in smaller children (lt 1 years) - Hypertension may persist after repair
99Coarctation Repair
Repair end-to-end anastomosis, Other types of
repair subclavian flap interposition
graft balloon angioplasty
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102Valvar Pulmonary Stenosis
- Systolic obstruction to outflow from the RV at
the pulmonary valve - Fused or absent pulmonary valve commissures
- Pulmonary valve cusps are thickened
- RV pressure must increase in order to deliver
cardiac output beyond the obstruction
103thickened pulmonary valve
104Hemodynamics of Valvar PS
- to maintain cardiac output, the RV pressure must
increase enough to overcome the stenosis - increased RV pressure results in RV hypertrophy
and decreased RV compliance - decreased RV compliance results in a need for
higher RA pressures to pump blood into R - increased RA pressure may result in R gt L
shunting across a patent foramen ovale if present
- cyanosis may occur
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106Clinical Picture Valvar PS
- History
- usually asymptomatic with a murmur
- neonates may present with cyanosis (R gt L
shunting at atrial level) - fatigue with exercise if severe stenosis
- May be associated with Noonans syndrome
107Noonan syndrome
- Disorder is distinct from Turner syndrome
- Female male
- Occurs in 1/1,000-2,000
- Clinical features overlap with other syndromes
108Examination Valvar PS
- murmur systolic ejection murmur at upper left
sternal border - turbulent blood crossing the stenotic pulmonary
valve - systolic ejection click
109CXR - Valvar PS
- usually normal
- poststenotic dilatation of main and left
pulmonary artery - neonate with cyanosis and severe pulmonary
stenosis - decreased pulmonary blood flow - if severe there may be RV enlargement
110CXR Normal heart size Dilated MPA post
stenotic dilation
111Natural History and Management - Valvar PS
- mild - does not usually progress
- moderate and severe - may be progressive
- balloon angioplasty has replaced surgical
valvotomy in most instances
112Angiogram of Valvar PS
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