Transcript 22. congenital cardiopathies

Pediatric
Congenital Heart
Disease
CHD
• Incidence: 5-8 per 1000 live births
– Major cause of death in first year of life (after
prematurity)
– Most common anomaly is VSD
– 28% of kids with CHD have another recognized
anomaly (trisomy 21, 13, 18, +++ )
Causes of CHD
• Chromosomal/genetic = 10%-12%
• Maternal or environmental = 1%-2%
– Maternal drug use
• Fetal alcohol syndrome—50% have CHD
– Maternal illness
• Rubella in 1st 7 wks of pregnancy→50% risk of defects
including PDA(Patent ductus arteriosus) and pulmonary
branch stenosis
• CMV, toxoplasmosis, other viral illnesses>> cardiac defects
• IDMs ( INFANTS OF DIABETIC MOTHERS) = 10% risk of CHD
(VSD, cardiomyopathy, TGA (transposition of great
arteries)most common)
• Multifactorial = 85%
Etiology of Congenital Heart Disease
OBSTRUCTIVE LESIONS
% of All Lesion
(Coarctation aortic/pulmonar stenosis)
ACYANOTIC LESIONS
VSD
ASD
PDA
CYANOTIC LESIONS
Tetralogy of Fallot
Transposition of great arteries
Truncus arteriosus
Total Anomalous Pulmonary Venous Return
Tricuspid atresia
(pulmonary atresia)
(hypoplastic left heart syndrome)
30-35
5-7
3-5
1-2
1-2
1-2
1-2
1-2
Older Classifications of CHD
• Acyanotic
– May become cyanotic
• Cyanotic
– May be pink
– May develop CHF
Newer Classification of CHD
• Hemodynamic characteristics
–
–
–
–
Increased pulmonary blood flow
Decreased pulmonary blood flow
Obstruction of blood flow out of the heart
Mixed blood flow
Increased Pulmonary
Blood Flow Defects
• Abnormal connection between two sides of
heart
– Either the septum or the great vessels
• Increased blood volume on right side of
heart
• Increased pulmonary blood flow
• Decreased systemic blood flow
Increased Pulmonary
Blood Flow Defects
• Atrial septal defect
• Ventricular septal defect
• Patent ductus arteriosus
Obstructive Defects
• Coarctation of the aorta
• Aortic stenosis
• Pulmonic stenosis
Decreased Pulmonary
Blood Flow Defects
• Tetralogy of Fallot
• Tricuspid atresia
Mixed Defects
• Transposition of great vessels
• Total anomalous pulmonary venous
connection
• Hypoplastic heart syndrome
– Right
– Left
ATRIAL SEPTAL DEFECT
• Normally, oxygen-poor
(blue) blood returns to the
right atrium from the body,
travels to the right
ventricle, then is pumped
into the lungs where it
receives oxygen. Oxygenrich (red) blood returns to
the left atrium from the
lungs, passes into the left
ventricle, and then is
pumped out to the body
through the aorta.
• An atrial septal defect
allows oxygen-rich (red)
blood to pass from the
left atrium, through the
opening in the septum,
and then mix with
oxygen-poor (blue)
blood in the right
atrium.
DEFINITION
• An atrial septal defect is
an opening in the atrial
septum, or dividing wall
between the two upper
chambers of the heart
known as the right and
left atria..
HEMODYNAMICS
• RT.ATRIUM RECEIVES
BLOOD FROM SUP. &
INF.VENA CAVA &
FROM LT. ATRIUM
• RT.ATRIUM ENLARGES
HEMODYNAMICS
• LARGE VOL OF BLOOD
FROM RT.ATRIUM
PASSES THRU
NORMAL TRICUSPID
VALVE &
PULMONARY VALVE
• DELAYED DIASTOLIC
MURMUR(LOW LT
STERNAL BORDER)
• RT.VENTRICLE
ENLARGES
• PULMONARY
EJECTION MURMUR
HEMODYNAMICS
• PULM. VALVE CLOSES
LATE & P2 IS DELAYED
• RV IS FULLY
LOADED,SO FURTHER
RISE IN RV VOLUME
CANNOT OCCUR
• WIDELY SPLIT S2
• FIXED SPLIT S2
• ACCENTUATED S2
PRESENTATION
•
•
•
•
•
•
recurrent chest infections
fatigue
sweating
rapid breathing
shortness of breath
poor growth
ON EXAMINATION
• INSPECTION
• PARASTERNAL
IMPULSE
• PALPATION
• SYSTOLIC THRILL AT
2ND LT SPACE
AUSCULTATION
•
•
•
•
WIDE FIXED SPLIT S2
ACCENTUATED P2
ESM AT LT 2nd & 3rd INTERSPACES
DELAYED DIASTOLIC MURMUR AT LOW LT
INTERSPACE
CXR FINDINGS
•
•
•
•
MOD. CARDIOMEGALY
RA ENLARGEMENT
RV ENLARGEMENT
PROMINENT MAIN
PULM ARTERY
• PLETHORIC LUNG
FIELDS
ECG CHANGES
• RT AXIS DEVIATION
• RT VENT HYPERTROPHY
• rsR’ PATTERN IN V1
ECHO PICTURES
SEVERITY ASSESMENT
• INTENSITY OF THE TWO MURMURS
• THE HEART SIZE
COMPLICATION
• PULMONARY HYPERTENSION (ABOVE 20
YEARS)
• DISAPPEARANCE OF DIASTOLIC MURMUR
• APPEARANCE OF PULM EJECN CLICK
• LOUD PALPABLE P2
• P2_STILL WIDELY SPLIT
MANAGEMENT
•
•
•
•
MEDICAL
ANTIBIOTICS FOR CHEST INFECTIONS
DIGOXIN TO INCREASE WORK OF HEART
DIURETICS TO REDUCE PRELOAD
REPAIR
SURGICAL REPAIR:DEVICES
VENTRICULAR SEPTAL DEFECT
• 2nd most common CHD(32%): CONGENITAL
HEART DISEASE
• SYNONYMS
* Roger’s disease
* Interventricular septal defect
* congenital cardiac anomaly
PATHOPHYSIOLOGY
• primarily depends on size & status of pulm. vascular bed rather than
location
• Small communication (less than 0.5cm`) VSD is restrictive &
rt.ventricular pressure is normal – does not cause significant
hemodynamic derangement (Qp:Qs=1.75:1.0)= RATIO OF
PULMONARY/SYSTHEMIC BLOOD FLOW
• Moderately restrictive VSD with a moderate shunt (Qp:Qs=1.5-2.5:1.0)
&poses hemodynamic burden on LV
• Large nonrestrictive VSDs (more than 1.0cm`) Rt&Lt ventricular
pressure are equalised(Qp:Qs is more than 2:1)
• Large VSDs at birth ,PVR ( pulmonary vascular resistance) may remain
higher than normal and Lt to Rt shunt may intially limited – involution of
media of small pulm.arterioles,PVR decreases—large Lt to Rt shunt
ensues
• In some infants large VSDs ,pulm. arteriolar thickness never decreases –
pulm.obstructive disease develops .when Qp:Qs=1:1 shunt becomes
bidirectional,signs of heart failure abate &pt. becomes cyanotic.
(Eisenmenger syndrome)
ANATOMICAL
CLASSIFICATION
typeI-MEMBRANOUS SEPTUM
paramembranous/perimembranous defect
(or infracristal,subaortic,conoventricular)
typeII-MUSCULAR SEPTUM
inlet,trabecular,central,apical,marginal or
swiss-cheese
typeIII-OUTLET SEPTUM deficient
supracristal,subpulmonary,infundibular or
conoseptal
SEPTAL DEFICIFNCY –AVseptal defect (AVcanal)
CLINICAL FEATURES
• Race : no particular racial predilection
• Sex :no particular sex preference
• Age :infants– difficult in postnatal
period,although ccf during first 6mths is
frequent,X-ray&ECG are normal.
children—after first year variable clinical
picture emerges.small VSD – asymptomatic
large VSD – common symptoms
-palpitation,dyspnoea on exertion,feeding
difficulties ,poor growth
-frequent chest infections
PHYSICAL FINDINGS
• Pulse pressure is relatively wide
• Precordium is hyperkinetic with a systolic thrill at LSB(
LEFT STERNAL BORDER)
• S1&S2 are masked by a PSM at Lt.sternal border ,max.
intensity of the murmur is best heard at 3rd,4th&5th Lt
interspace.Also well heard at the 2nd space but not
conducted beyond apex
• Presence of mid-diastolic ,low pitched rumble at the
apex is caused by increased flow across the mitral valve
&indicates Qp:Qs=2:1/greater
• Maladie de Roger –small VSD presenting in older
children as a loud PSM w/o other significant
hemodynamic changes
INVESTIGATIONS
• ECHOCARDIOGRAPHY
two-dimensional &doppler colour flow
• CHEST RADIOGRAPHY
- normal
- biventricular hypertrophy
- pulmonary plethora
• ELECTROCARDIOGRAPHY
-smallVSD ~ normal tracing
-mod.VSD ~ broad,notched P wave characteristic of Lt.
Atrial overload as well as LV overload,namely,deep Q
waves & tall R waves in leads V5 and V6 and often AF
-large VSD ~RVH with rt. axis deviation. With further
progression biventricular hypertrophy;P waves may be
notched/peaked.
Other investigations
• CAT SCAN
(Computed Axial Tomography)
• MRI
• ULTRASOUND
• ANGIOGRAPHY
(cardiac catheterization and angiography)
COMPLICATIONS
•
•
•
•
•
•
Congestive cardiac failure
Infective endocarditis on rt.ventricular side
Aortic insufficiency
Complete heart block
Delayed growth & development (FTT) in infancy
Damage to electrical conduction system during
surgery(causing arrythmias)
• Pulmonary hypertension
INTERVENTION
• 3 MAJOR TYPES
• SMALL (less than 3mm
diameter)
- hemodynamically
insignificant
- b/w 80-85% of all VSDs
- all close spontaneously
* 50% by 2yrs
* 90% by 6yrs
* 10% during school yrs
- muscular close sooner
than membranous
NEWBORN VSD
•
Most common lesion
•
2/3rds close spontaneously
•
Small VSD
•
Definite murmur
•
Will probably close
•
Large VSD
•
No murmur
•
No problems
•
Home with Mom
• MODERATE VSDs
* 3-5mm diameter
* least common group of children(3-5%)
* w/o evidence of ccf/ pulm.htn can be
followed until spontaneous closure occurs.
• LARGE VSDs WITH NORMAL PVR ( pulmonary
vascular resistance)
* 6-10mm in diameter
* usually requires surgery otherwise…
develop CCF ( congestive cardiac failure) & FTT
( failure to thrive) by age of 3-6mths.
Conservative treatment
- treat CCF & prevent development of
pulm.vascular disease
- prevention & treatment of infective
endocarditis
Evaluation of Cyanotic
Heart Disease
Physical Examination

Central Cyanosis vs. Peripheral cyanosis

Vital signs

Lung and CNS examination to rule these out

Cardiac Examination





Heaves, thrills, abnormal or increased precordial activity
Absent or diminished femoral pulses
Abnormal first or second heart sound (abnormal splitting)
Extra heart sounds (gallop, ejection click, opening snap)
Murmurs that are loud, harsh, blowing
Initial evaluation of child’s heart
Physical exam
•Listen to heart first when/if infant quiet
(warm stethoscope)
•First concentrate on S1 and especially S2
Louder than normal?
Split normally?
•Systolic murmur:
Starts after or obscures S1?
•Diastolic murmur?
•Widely radiating murmur?
•Palpate liver
•BP in arm and leg
•Tongue - cyanosis
History

Difficulty feeding, irritablility, diaphoresis (perspiring
profusely), failure to thrive (FTT)

Prenatal history: maternal diabetes, SLE

Congenital Infections (TORCH)

Drugs taken in pregnancy

Family history: heart problem before 50 y.o.

Chromosomal Abnormalities
Lab/Imaging Studies

CBC/Sepsis evaluation

Chest x-ray

Oxygen Saturation (Arterial blood gas, pulse oximetry)

Hyperoxia test

Electrocardiogram

Echocardiography
Transposition of Great Arteries
Second most common cause of cyanosis in infancy
Pulmonary and systemic circulations form two separate circuits
Must be mixing between two circuits for life
“egg-shaped
silhouette”
Clinical Findings

Severe cyanosis present at birth

1/3 have VSD, some have ASD

Some have subpulmonic stenosis

Loud, single S2

Systolic murmur indicates VSD or pulmonic stenosis

ECG reveals right ventricular hypertrophy
Transposition of Great Arteries: Tx

PGE1 administration necessary

Balloon atrial septostomy necessary (Rashkind
procedure)

Arterial Switch procedure performed first week of
life
Hypoplastic Left Heart
Presents first week of life, as
PDA closes symptoms develop
PGE administration
Ductal dependant systemic blood
flow
Tricuspid Atresia
Tricuspid valve fails to develop
Hypoplasia of right heart
Venous blood from right atrium depends on open ASD or
PFO, VSD, PDA
Tricuspid Atresia-Clinical Findings

Progressive cyanosis as PDA closes

30% transposition of great arteries

70% some degree of Pulmonic stenosis

Tacypneic, single S2

Systolic murmur along left lower sternal border (VSD)

ECG reveals left ventricular hypertrophy
Truncus Arteriosus
Failure of primitive truncus arteriosus to divide into aorta and pulm A.
VSD almost always present
Right Sided-arch in about 33%
Cardiomegaly, increased pulmonary vascularity,
right aortic arch
TETRALOGY OF FALLOT
• COMMONEST CYANOTIC CONGENITAL
HEART DISEASE
• 10 % OF ALL CONGENITAL HEART DISEASES
MORPHOLOGY
FOUR MORPHOLOGICAL DEFECTS
1. VENTRICULAR SEPTAL DEFECT
2. RIGHT VENTRICULAR OUTFLOW TRACT
OBSTRUCTION
•
•
•
SUBVALVAR
VALVAR
SUPRAVALVAR
3. OVERRIDING OF THE AORTA
4. RIGHT VENTRICULAR HYPERTROPHY
MORPHOLOGY OF NORMAL HEART
MORPHOLOGY IN T.o.F
Subvalvar
Obstruction
Tetralogy of Fallot
Most Common cause of cyanotic heart disease beyond neonatal period
Degree of Pulmonary stenosis and size of VSD determine presentation
Variable degree of Cyanosis
“Boot Shaped
Heart”
ALTERED PHYSIOLOGY
• OBSTRUCTION TO FLOW OF
DEOXYGENATED BLOOD FROM THE RIGHT
VENTRICLE TO THE PULMONARY ARTERY
• DECREASED OXYGENATION DUE TO POOR
PERFUSION OF THE BLOOD
ALTERED PHYSIOLOGY
• SHUNTING OF DEOXYGENATED BLOOD
FROM THE RIGHT VENTRICLE TO THE
AORTA ACROSS THE VENTRICULAR SEPTAL
DEFECT (FACILITATED BY AORTIC
OVERRIDE)
• POOR SYSTEMIC OXYGENATION, LOW
HEMOGLOBIN SATURATION AND
CYANOSIS
CLINICAL PRESENTATION
• CYANOSIS NOT USUALLY NOTICED AT
BIRTH
• CAUSES
– CHILD LESS ACTIVE IN THE INITIAL FEW
MONTHS
– FOETAL HEMOGLOBIN HAS MORE AFFINITY
FOR OXYGEN THAN ADULT HEMOGLOBIN
CLINICAL PRESENTATION
• CYANOSIS MANIFESTS MORE AS CHILD
BECOMES MORE ACTIVE
• PHYSICAL GROWTH IS > GOOD <
• MENTAL DEVELOPMENT MAY BE DELAYED
IN SEVERE CASES DUE TO CHRONIC
HYPOXIA OF THE BRAIN
Clinical Findings






Squatting
“Tet spells”
due to pulmonary
outflow tract spasm
Severe cases -at birth
severe PS( pulmonary
stenosis
Mild cases – much
later- mild PS
Cyanosis usually
ECG reveals right ventricular hypertrophy
CYANOTIC SPELLS
• TYPICAL OF FALLOT’S TETRALOGY
• USUALLY OCCURS WHEN THE CHILD
CRIES OR IS VERY ACTIVE AS WHEN
THE CHILD WAKES UP FROM SLEEP
CYANOTIC SPELLS
• ACTIVITY RESULTS IN
– INCREASES OXYGEN DEMAND
– DECREASES SYSTEMIC VASCULAR RESISTANCE
– INCREASES SYMPATHETIC ACTIVITY WHICH
CAUSES INFUNDIBULAR SPASM, I.E.,
INCREASE IN THE MUSCULAR OBSTRUCTION
TO THE RIGHT VENTRICULAR OUTFLOW AT
THE SUBVALVAR LEVEL
SQUATTING
• TYPICAL OF FALLOT’S TETRALOGY
• CHILD ASSUMES SQUATTING POSTURE VERY
FREQUENTLY
• SOME POSTURES MAY BE CALLED ‘SQUATTING
EQUIVALENTS’
• REASON IS THAT SQUATTING CAUSES AN
INCREASE IN RESISTANCE TO SYSTEMIC FLOW –
DECREASED SHUNTING ACROSS THE VSD – LESS
DESATURATION OF SYSTEMIC BLOOD
NATURAL HISTORY
• WIDE SPECTRUM OF CLINICAL
MANIFESTATIONS DEPENDING ON
SEVERITY OF ABNORMALITIES, I.E.,
DEGREE OF OBSTRUCTION TO RIGHT
VENTRICULAR OUTFLOW, AND SIZE OF
VSD
TREATMENT OPTIONS
• ONLY SURGICAL
– PALLIATIVE SURGERY
– DEFINITIVE SURGERY
PALLIATIVE SURGERY
• AIMED TO DIVERT SYSTEMIC BLOOD INTO THE
PULMONARY CIRCULATION AND THUS ENHANCE
PULMONARY FLOW AND OXYGENATION
• STANDARD OPERATION IS THE MODIFIED
BLALOCK-TAUSSIG SHUNT OR OTHER SYSTEMIC
PULMONARY SHUNTS SUCH AS POTT’S SHUNT
AND WATERSTON-COOLEY SHUNT
Systemic to Pulmonary Shunts
Tetralogy Of Fallot
Treatment of Tet Spell
•Knee-chest position
•O2
•Morphine 0.1-0.2 mg/kg IM,IV
•Phenylephrine gtts : increase systolic BP 20-40 mmHg
•Beta blockade, e.g. propanolol: titrate to 0.1 mg/kg
•ABG: NaHCO3 if necessary
•Surgery
DEFINITIVE SURGERY
• RELIEF OF RIGHT VENTRICULAR OUTFLOW
TRACT OBSTRUCTION
• SEPARATION OF SYSTEMIC AND
PULMONARY CIRCULATIONS BY CLOSURE
OF THE VSD
TREATMENT STRATEGIES
• PALLIATIVE SURGERY IN EARLY
CHILDHOOD FOLLOWED BY DEFINITIVE
SURGERY IN THE LATER YEARS, USUALLY
AFTER 3 – 4 YEARS OF AGE
• DEFINITIVE SURGERY IN THE NEONATAL
PERIOD OR EARLY CHILDHOOD
T.O.F IN ADULT CARDIAC SURGICAL
HOSPITAL
• DELAYED DEFINITIVE REPAIR FOLLOWING
SHUNT IN EARLY CHILDHOOD
• DELAYED PRESENTATION, FOR DEFINITIVE
REPAIR
• RE-OPERATION FOR DELAYED
COMPLICATIONS AFTER DEFINITVE REPAIR
Patent Ductus Arteriosus
Patent Ductus Arteriosus
●The ductus arteriosus in the fetus is an
important conduit that allows
deoxygenated blood to bypass the
collapsed lungs and enter the placenta
through the descending aorta and
umbilical arteries.
Patent Ductus Arteriosus
● The placenta acts as an oxygenator and
returns oxygen rich blood through the
umbilical vein and ductus venosus to the
fetal heart.
● The placenta produces prostaglandins,
which maintain prenatal patency of the
ductus and, in early gestation, inhibit the
ability of the ductus to contract in response
to oxygen.
Patent Ductus Arteriosus
● During the postnatal period, final closure of
the ductus arteriosus results from
increased production of local
vasoconstrictors (like endothelin) in
response to higher arterial oxygen,
removal of placental prostaglandin and a
decrease in the number of prostaglandin E2
receptors in the ductal wall.
Patent Ductus Arteriosus
• The direction of blood flow across the
PDA depends on the balance of
pulmonary and systemic vascular
resistance.
Patent Ductus Arteriosus
• The most reliable non-invasive diagnostic
tool is echocardiography with Doppler
ultrasound.
• In most infants, a modified parasternal
short axis view offers the best window for
PDA visualization.
• This view offers the best opportunity to
directly measure the PDA.
Patent Ductus Arteriosus
Patent Ductus Arteriosus
• The secondary effects of the increased flow
can estimate the volume load from the left
to right ductal shunt.
• A large shunt leads to dilation of the left
atrium and left ventricle, as well as
holodiastolic reversal of blood flow distal to
the ductus in the descending aorta due to
run off into the pulmonary bed.
Patent Ductus Arteriosus
• The clinical features depend on the
magnitude of left-to-right shunt through
the PDA and the ability of the infant to
initiate compensatory mechanisms to
handle the extra volume load.
Relationship to Systemic Organ Perfusion
with PDA
• Redistribution of systemic blood flow
occurs even with moderate shunts.
• Retrograde aortic flow, decreased systemic
blood flow, and moderate hypotension are
common in premature infants with a PDA
and may lead to decreased perfusion in
many organs, with potential clinical
consequences to each.
Relationship to Systemic Organ Perfusion
with PDA
• Reduced cerebral blood flow or changes in
cerebral blood flow velocity patterns have
been implicated in the occurrence of
intraventricular hemorrhage.
• Renal function may be compromised, and
myocardial perfusion, particularly
subendocardial blood flow, may be
reduced.
PDA Consequences
•
•
•
•
•
Pulmonary Edema
Pulmonary Hemorrhage
Bronchopulmonary Dysplasia
incidence of Necrotizing Enterocolitis
incidence of Intraventricular Hemorrhage
Signs and Symptoms
• 2-3 days after birth up to 1 week of life
o
•
•
•
•
later in those treated with surfactant
prominent left ventricular impulse
bounding pulses
widened pulse pressure (>25 mmHg)
murmur
o
o
o
can be initially silent
initially systolic becoming continuous
machinery like
Treatment of PDA
• Simple fluid restriction along with diuretic
use is often recommended to control the
symptoms of a PDA.
• Furosemide is commonly used. Although
furosemide is a prostaglandin agonist, it
does not interfere with PDA closure.
Treatment of PDA
• The use of oral or, preferably, intravenous
(lyophilized) indomethacin to constrict the
ductus arteriosus has led to successful
nonsurgical closure in a large proportion of
treated infants; the effects of indomethacin
apparently are best when it is administered
before 10 days of age and in less mature
infants.
Treatment of PDA
• Dose schedules vary, but commonly a first dose of
0.2 mg/kg is given by nasogastric tube or
intravenously.
• For intravenous indomethacin, subsequent doses
depend on the age at initial treatment if <48
hours, the subsequent two doses are 0.10 mg/kg;
if 2 to 7 days, 0.20 mg/kg; and if >7 days, 0.25
mg/kg. A total of three doses usually is given 12
to 24 hours apart depending on urinary output; if
urine flow decreases, fewer doses may be used or
the time between doses may be extended.
Treatment of PDA
Surgical ligation
• In small infants that are not a candidate
for, or who have failed, medical therapy,
surgical ligation remains an effective
alternative.
Postnatally
PGE2
PGE2
O2
O2
Nitric Oxide
Prenatal Cortisol
PDA remains
patent
Closure of
PDA