7.congenital heart dss
DESCRIPTION
3rd year, 3rd rotationTRANSCRIPT
CONGENITAL HEART DISEASES
Nursakinah bt BohariSalwa Hanim bt Mohd Saifuddin
Siti Hajar bt Wahid
Circulatory Changes at birth
The LA pressure is low The RA pressure is higher
than LA ( receives all sys VR)
The flap valve of foramen ovale is held open
Blood across the atrial septum to LA
With the 1st breath, resistance to pulm BF falls and volume of blood returning to RA falls
Changes in pressure difference cause flap valve of FO to be closed.
The ductus arteriosus will normally close within first few hrs or days
Some babies with CH lesion rely on BF through the duct. Clinical condition
deteriorate dramatically when duct closed (1-2 days)
Congenital heart disease
Definition: Failure of normal cardiac development or persistent of the fetal circulation after birth.
Epidemiology
CHD occurs in 8 per 1000 infants . About 1 in 10 stillborn infants have a
cardiac anomaly. About 10-15% have complex lesions
with more than 1 cardiac abnormality. About 10-15 % also have non-cardiac
abnormality. CHD is the most common group of
structural malformations in children.
Classification
CHD
Acyanotic Cyanotic
Left-to-right shunts
Left-to-right shunts
Outflow obstruction
Outflow obstruction
- Ventricular Septal Defect (VSD)
- Persistent Ductus Arteriosus (PDA)
- Atrial Septal Defect (ASD
- Pulmonary Stenosis
- Aortic Stenosis
-Coarctation of aorta
Teralogy of Fallot transposition of the great arteries Atrioventricular septal defect
Etiology Most cases are multifactorial.
Left-to-right shunts
Ventricular Septal Defects (VSD) Common – 25-30% of all cases of CHD. There is a defect anywhere in the
ventricular septum, usually perimembranous (adjacent to the tricuspid valve) or muscular (completely surrounded by muscle).
Location of the VSD – prognostic and repair approach.
The amount of flow crossing a VSD depends on the size of defect and the pulmonary vascular resistance.
At birth, the pulmonary vascular resistance is normally elevated, thus, even large VSDs are not symptomatic at birth.
Over the first 6-8 weeks of life, pulmonary vascular resistance normally decreases. More blood flows through the lung and into the left atrium. However, in VSD, the amount of shunt increases, and symptoms may start to develop.
The size of the VSD affects the clinical presentation.
Pathophysiology
VSD permits a left-to-right shunt to occur at the ventricular level with 3 adverse hemodynamic consequences:
1. left ventricular (LV) volume overload,2. increased pulmonary blood flow,3. compromise of systemic cardiac output. In time, as PVR increases, irreversible
histologic changes may occur within the pulmonary vascular bed.
Untreated, a reversal of the flow occurs, leading to a right-to-left shunt with the development of increasing cyanosis (Eisenmenger complex).
Small VSDs
Smaller than the aortic valve in diameter (3mm).
Clinical features Symptoms
Asymptomatic Physical signs
Thrills at lower sternal edge Loud pansystolic murmur at lower left sternal
edge Quiet pulmonary second sound (P2)
Investigations Chest X-ray - normal ECG - normal Echocardiography Demonstrates the precise anatomy of
the defect. Assessment of haemodynamic effect using Doppler echocardiography.
Management Most will close spontaneously. Ensure by
the disappearance of the murmur, normal ECG on follow up, normal echocardiogram.
While the VSD is present, for prevention of bacterial endocarditis :Maintain good dental hygieneAntibiotic prophylaxis before dental
extraction or any operation where there’ll be bleeding
Surgical closure may not be required
Large VSDs
Defects are the same size or bigger than the aortic valve.
Clinical features Symptoms
Heart failure with breathlessness and failure to thrive after 1 week old
Recurrent chest infections Physical signs
Prominence of the left precordium Soft pansystolic murmur Apical mid-diastolic murmur at the apex Loud pulmonary second sound (P2) Tachypnoea, tachycardia and enlarged liver from
heart failure.
Investigations Chest X-ray
Cardiomegaly Enlarged pulmonary arteries Pulmonary vascular markings Pulmonary oedema
ECG Biventricular hypertrophy by 2 months of age and
signs of pulmonary HPT right ventricular enlargement and hypertrophy
Echocardiography Demonstrates the anatomy defect, haemodynamic
effects and severity of pulmonary HPT.
X-Ray chest PA View There is cardiomegaly, prominent main pulmonary artery segment and right pulmonary artery. Enlarged left pulmonary artery shadow is seen below the left cardiac border, within the cardiac silhouette. The enhanced vascular markings are visible on the right side whereas it is obscured by the cardiac shadow on the left side
cardiomegaly
Increased pulm markings
Enlarged pulm arteries
Management Initial treatment – diuretics and
digoxin/captopril. Continued poor growth or pulmonary HPT
requires closure of the defect. Most VSDs are by surgery. But muscular
defects by devices placed at cardiac catheterization.
Surgery is usually done at 3-6 months of age for :Managing heart failure and failure to thrive.Prevent permanent lung damage from
pulmonary HPT and high blood flow.
Complications
Eisenmenger complex Secondary aortic insufficiency Aortic regurgitation RV outflow tract obstruction Subaortic obstruction Infective endocarditis
Atrial Septal Defects (ASD)
Due to failure of septal growth or excessive reabsorption of tissue.
Represent about 10% of CHD. Classification:
Secundum ASD (80%) Defects occur from either excessive resorption of septum
primum or from deficient growth of septum secundum. Primum ASD or partial atrioventricular septal
defect Incomplete fusion of septum primum with the endocardial
cushion. An inter-atrial communication b’ween the bottom
end of the atrial septum and the atrioventricular(AV) valves.
Abnormal AV valves, with a left AV valve having 3 leaflets and tends to leak (regurgitant valve).
Sinus venosus defect (least common) Associated with anomalous pulmonary venous
return
Pathophysiology
Shunting across an atrial septal defect is left to right The degree of this shunting is dependent on;
- the size of the defect
- the relative compliance of the right and left ventricles.
- the relative vascular resistance in the pulmonary and systemic circulations.
Resistance in the pulmonary vascular bed is commonly normal in children with ASD, and increase in volume load is usually well tolerated
However, altered ventricular compliance with age can result in an increased left-to-right shunt contributing to symptoms.
The chronic significant left-to-right shunt can alter the pulmonary vascular resistance leading to pulmonary arterial hypertension, even reversal of shunt and Eisenmenger syndrome.
Echocardiography:RV dilation with RV pressure overload as evidenced by flattening of the interventricular septum in systole.
Management
Prognosis & Complications
ASDs detected in term infants may close spontaneously. Secundum ASDs are well tolerated during childhood, and symptoms do not usually appear until the 3rd decade or later.
Complications:− Congestive heart failure− Arrhythmias− Pulmonary hypertension− Cyanosis− Stroke− Infective endocarditis− Surgery may be associated with a long-term risk of
atrial fibrillation or flutter. The risk of infective endocarditis exists during the first 6 months after surgery.
Patent Ductus Arteriosus
Patent Ductus Arteriosus (PDA)
The ductus arteriosus allows blood to flow from the pulmonary artery to the aorta during fetal life. This changes to the opposite after birth.
In term infants, it normally closes shortly after birth. Failure of the normal closure of it by a month post term is due to a defect in the constrictor mechanism of the duct.
In preterm infants, the PDA is not from CHD but due to prematurity.
Pathophysiology
Higher aortic pressure, blood shunts left to right through the ductus
The magnitude of the excess pulmonary blood flow depends on: − The larger the internal diameter of the narrowest portion of
the ductus arteriosus, the larger the left-to-right shunt. − If the ductus arteriosus is restrictive, then the length of the
narrowed area also affects the magnitude of the shunt. A longer ductus is associated with a smaller shunt.
− Relationship of the pulmonary vascular resistance to the systemic vascular resistance. If the systemic vascular resistance is high and/or the pulmonary vascular resistance is low, the flow through the ductus arteriosus is potentially large.
If the PDA is large, pulmonary artery pressure may be elevated to systemic levels during both systole and diastole. Extremely high risk for the development of pulmonary vascular disease if left unoperated.
d) PDA visualised on angiography. e) A coil used to close the ducts. It’s passed through a catheter via the femoral artery. f) angiogram to show coil in the duct
Complication
Complications include the following:− Endocarditis− Congestive heart failure− Pulmonary vascular obstructive disease− Aortic rupture
ACYNOTIC
Outflow Obstruction
Outflow Obstruction
Pulmonary stenosis – 7 % Aortic stenosis – 5 % Coarctation of the aorta – 5%
Pulmonary stenosis
Narrowing of the pulmonary valve opening that increases resistance to blood flow from the right ventricle to the pulmonary arteries.
Site: Valvar (most), supravalvar, or subvalvar The valve may have
only two or one leaflets The leaflets that are
partially fused together Three leaflets, but thick
and partly or completely stuck together
narrowing of the valve
Pathophysiology
The right ventricle pump harder and at a higher
pressure to propel blood through the valve
Right ventricular hypertrophy
Pulmonary valve is mildly to moderately
narrowed
severe stenosis in a neonate
Right ventricle cannot eject sufficient volume of blood flow into the pulmonary
artery
Right ventricular pressure becomes extremely high
Right-to-left shunt
cyanosis
Lead to right-to-left shunting through a patent foramen ovale/atrial septal defect
Clinical features
Severity depend on degree of stenosis Most asymptomatic (mild) Moderate – Severe :
Exertional dyspnoea, easily fatigability, rapid breathing, shortness of breath, chest pain (angina), cyanosis
may develop as the child gets older.
Physical sign: heart murmur Sys ejection murmur best heard at 2nd IS
(P2) which radiates to the back Thrill may present In severe: impulse at the left sternal
border(RVH) Often associated with click sound
Investigation
Normal or post-stenotic dilation of the pulmonary artery
Shows evidence of right ventricular hypertrophy
Chest X-ray ECG
(a) Pulmonary valve stenosis. (b) Murmur. (c) Chest X-ray. (d) ECG.
Management
• Mild: (peak sys gradient < 50 mmHg)– Treatment not indicated– SBE prophylaxis
• Moderate-severe (>50 mmHg)– Transcatheter ballon valvuloplasty
• Neonatal critical PS– Charc: cynosis and Rvdysfn– Temporary stabilization with IV prostaglandin
E infusion– Early transcatheter ballon valvuloplasty
Aortic stenosis
a narrowing of the valve that opens to allow blood to flow from the left ventricle into the aorta and then to the body.
Valvular, subvalvular or supravulvalar – 5%
Failure of : development of
the three leaflets Resorption of
tissue around the valve
Pathophysiology narrowed aortic valve
the LV must pump under very high pressures
Left ventricular hyperthropy
• Mild stenosis: usually well tolerated, with minimal hypertrophy and normal LV function.
• Severe hypertrophy and valvar obstruction: myocardial ischemia dt limited CO, reduced coronary perfusion, and increased myocardial oxygen consumption. •Fibrosis may occur in areas of the myocardium damaged by ischemia.
Clinical manifestation
Depend on degree of stenosis Mild to moderate : asymptomatic Severe:
easy fatigability, exertional chest pain, syncope
In infant with severe stenosis can survive only if: PDA permits flow to the aorta and coronary
arteries
• Physical sign:
– Small volume, slow rising pulse– Sys ejection murmur at R2ndIS and radiating
to neck– Apical ejection click– Thrill at RUS border/suprasternal notch/carotid
• Cong bicuspid aortic valve:– Prone to calcific degeneration in middle age– Increased risk of infective endocarditis
• Single cusp AV : commonly aw early sudden death
Investigation
ECG and CXR Mild: both normal Moderate – severe:
CXR: LVH, poststenotic dilation of ascending or aortic knob
ECG : site, valve morphology, LVH and estimated pressure gradient
(a) Aortic stenosis. (b) Murmur. (c) Chest X-ray. (d) ECG.
Treatment
Ballon valvulopasty Symptoms on exercise/ high resting
pressure gradient(>64mmHg) High risk of significant valvular insufficiency
Surgical mx When BV unsuccesful or significant valvular
insufficiency develops Subacute bacterial endocarditis
prophylaxis
Coarctation of aorta
a narrowing of the aorta, usually just before the point where the ductus arteriosus joins the aorta.
Its almost always juxtaductal in position (98%)
2X more common in males 25% of patients with Turner’s Syndrome
have coarctation of aorta Associated Defects:
Bicuspid aortic valve (most commonassociated defect seen in 50%)
VSD ASD
Pathophysiology
afterload on the left ventricle (LV), which results in increased wall stress
LV hypertrophy
• LV afterload may gradually increase, allowing children with less severe coarctation to develop arterial collateral vessels that partially bypass the aortic obstruction. • These children may be asymptomatic until hypertension is detected or another complication develops.
• Acute increased in afterload lead to rapid development of CHF and shock.
The aorta narrows
reduces blood flow to the lower half of the body
the BP is lower than normal in the legs and tends to be higher than normal in the arms
HPT
Clinical manifestation Depends on the severity of COA Asymptomatic In older children:
Leg discomfort with exercise Headache Epistaxis
Infant severe COA: Dependent on a PD to provide flow to des
aorta Closed: resp distress, shock
Physical sign:
Systemic HPT in the arm Diminished lower extremities pulses
Radio-femoral delay: blood bypassing the obst via collateral vessels
in the chest wall Ejection sys murmur at US edge
Investigation
CXR : rib notching with large collaterals
ECG: LVH
(a) Coarctation of the aorta. There is narrowing of the aorta distal to the left subclavian artery adjacent to the insertion of the arterial duct. (b) Murmur. (c) Chest X-ray. (d) ECG.
CHEST XRAY
red : rib notching caused by the dilated intercostal arteries.yellow : the aortic knobblue : the actual coarctationgreen : the post-stenotic dilation of the descending aorta.
Coarctation of the Aorta
Management
Neonatal severe COA: Sick infant require temporary stabilization
Mechanical ventilation Correction of met acidosis, hypoglycaemia and EI IV PE infusion
Early surgical repair
Asymptomatic/ older children: Depends on morphology of coarctation and age of
presentation Primary transcatheter ballon angioplasty Stent implantation Surgical repair
Summary
Lesion Signs Management
Aortic stenosis • Murmur: upper Rsternal edge• carotid thrill
Ballon dilatation
Pulmonary stenosis •Murmur: upper L sternal edge• no carotid thrill
Ballon dilatation
Coarctatio of aorta • systemic HPT•Radio-femoral delay
Stent insertion or surgery
CYANOTIC HEART DISEASEBy: SALWA HANIM BINTI MOHD SAIFUDDIN (2008289416)
Definition:
Cyanosis: A bluish discoloration of skin and mucous
membrane due to excessive concentration of reduced hemoglobin (deoxygenated) in the blood
(Dorland’s Pocket Medical Dictionary, 27th ed.)
Central vs peripheral
Central cyanosis: Seen on tongue as a slate blue colour Associated with a fall in arterial blood O2 tension. Clinically:
reduced(deoxygenated) Hb >5g/dL SpO2= <85%
Anemia? Polycythemia?
Peripheral cyanosis: Blueness of hand and feet Due to cold or circulatory disorder (e.g: PVD, DVT) Can also occur in severe central cyanosis
(Illustrated Textbook of Paediatrics, 3rd ed., p.287)
Causes of cyanosis in CHD:
RIGHT to LEFT shunt
Systemic venous return
Right heart
Left heart
Systemic circulation
5”Ts”
1. Tetralogy of Fallot2. Transposition of the great arteries3. Tricuspid atresia4. Truncus arteriosus5. Total anomalous pulmonary venous
return
1.TETRALOGY OF FALLOT
Introduction:
Most common cyanotic CHD, ~10% of all CHD
4 structural defects Pulmonary stenosis (most commonly subvalvular or
infundibular) Overriding of the aorta Ventricular septal defect,VSD (L). Right ventricular hypertrophy, RVH
Due to abnormalities in the septation of the truncus arteriosus into the aorta and pulmonary arteries that occur early in gestation (3-4weeks)
(Nelson p674)
Clinical manifestations:
Most are dx:1. Antenatally2. 1st and 2nd month of age: Pulmonary stenosis
causing ejection systolic murmur.
Cyanosis: the degree depends on the amount of PS
Older children+ long standing cyanosis+ not undergone surgery Dusky blue skin Grey sclerae with engorged blood vessel Marked clubbing of fingers and toes
Hypoxic spells/ paroxysmal hypercyanotic attacks (1st 2years of life)
Severe hypoxia tissue acidosis breathlessness and pallor
Rapid increase in cyanosis Restless and agitated Inconsolable crying An ambulatory toddler may squat Severe spells:
Prolonged unconsciousness and convulsions Hemiparesis OR death
Investigations:
Chest X-ray Small heart Uptilted apex (boot shaped) pulmonary artery ‘bay’= concavity of L heart border Oligaemic lung fields
ECG At birth normal Older: R axis deviation and RVH
Echocardiography Levels of PS and degree of stenosis Coronary anomalies(5% in TOF)
(Nelson p675)
Management:
1. Single stage primary surgical repair between 1-2years old
2. Indications for palliative modified Blalock Taussig shunt:
Hypercyanotic spells/ severe cyanosis <6months Small pulmonary arteries Anomalous coronary artery crossing in front of RV
outflow tract
3. Life-long follow up(Handbook of Hospital Paediatrics, 2nd ed., p94 )
2.TRANSPOSITION OF GREAT ARTERIES
Introduction:
5% of CHD (the most common cyanotic CHD in newborn period)
Ventriculoarterial discordance 20 to abnormalities in septation of truncus arteriosus
Aorta arises from the RV, anterior and to the right of the pulmonary artery, which arises from the left ventricle
Naturally occurring associated anomalies that cause mixing: VSD ASD PDA
Clinical manifestations
Cyanosis is always present Finger clubbing Quiet tachypnea Single S2 Usually no murmur Signs of CHF in children with
transposition and a large VSD.
Investigations:
Chest x-ray Narrow upper mediastinum with an ‘egg on side’
appearance of the cardiac shadow Increased pulmonary vascular markings
ECG Right axis deviation and RVH
Echocardiography Transposition of the great arteries The sites Amount of mixing
Management:
Simple (TGA) with intact ventricular septum: IV Prostaglandin E1 infusion Early Balloon arterial septostomy (BAS) Surgery: arterial switch procedure (2-4weeks of age)
TGA with VSD: No treatment during neonatal period, but may develop
heart failure 1-2months age Elective one-stage arterial switch operation + VSD
closure before three months of age.
TGA with VSD and PS: Blalock Taussig shunt during infancy followed by Rastelli
repair at 4-6years of age.
3.TRICUSPID ATRESIA
Introduction:
Approximately 2% of all CHD
Normal development of the valve from endocardial cushions and septal tissue fails
RV is small and nonfunctional (hypoplastic)
All systemic venous return must cross the atrial septum into the left atrium.
PDA,ASD and VSD are necessary
Clinical manifestations:
Severely cyanosis Single S2
If VSD present, pansystolic murmur may be audible.
Investigations:
Chest x-ray: Normal or mildly enlarged Oligaemic lung fields
ECG: LVH Superior QRS axis
Echocardiograph Lesions Source of pulmonary blood flow
Management:
Small or no VSD: PG E1
Surgery: Blalock Taussig procedure Bidirectional Glenn and Fontan procedure Complete corrective surgery: not possible
4. Truncus arteriosus
Introduction:
<1% of all cases of CHD
Failure of septation of the truncus arteriosus (3-4weeks of gestation)
Large single arterial trunk and VSD immediately below the valve
Clinical manifestations:
Degrees of cyanosis depends on amount of pulmonary blood flow
Infant may develop signs of CHF Signs:
Tachypnea and cough Peripheral pulses are bounding Single S2
Systolic murmur at left sternal border
Investigations:
Chest x-ray: Increase pulmonary blood flow Displaced pulmonary arteries
ECG: Combined ventricular hypertrophy Cardiomegaly
Echocardiography: VSD Truncal valve function Origin of the pulmonary arteries
Management:
Medications: anticongestive medications Surgery:
VSD closure Placement of conduit between the right
ventricle and pulmonary arteries before 3months of age.
5. Total Anomalous Pulmonary Venous Return
Introduction
1% of CHD
Disruption of normal development of normal pulmonary venous drainage during the 3rd week of gestation results in 1 of 4 abnormalities
4major anatomic types:1. Supracardiac2. Cardiac3. Infracardiac4. Mixed
Clinical manifestations:
Depends on the presence or absence of obstruction to the pulmonary venous drainage Infants with obstruction: cyanosis, marked
tachypnea, dyspnea and signs of RHF
Continuous murmur Hyperactive right ventricular impulse Widely split S2
Ejection systolic murmur at the left upper sternal border
Investigations:
Chest x-ray: normal or mildly cardiomegaly Varying degrees of pulmonary edema
ECG: With obstruction: RV volume overload Right axis deviation RVH
Echocardiograhy: Right heart volume overloaded R-L atrial level shunting PV (site of drainage and degree of obstruction)
Treament:
Surgery: Open and ligation
SUMMARYLESION CLINICAL FEATURES MANAGEMENT
TOF Loud murmur at the upper left sternal edge, with a single second heart soundClubbing of fingers and toes (older)Hypercyanotic spells (rare)
Surgery at 1-2years
Tranposition of the great arteries
Cyanosis is typicalSingle S2Usually no murmur.
Prostaglandin infusion, some need balloon atrial septostomy at diagnosisArterial switch operation in neonatal period
Tricuspid atresia Severely cyanoticSingle S2Pansystolic murmur
PG E1Shunt (Blalock-Taussig) or pulmonary artery banding Surgery (Bidirectional Glenn and Fontan procedure)
Truncus arteriosus Tachypnea and coughPeripheral pulses are boundingSystolic murmur at left sternal borderSingle S2
anticongestive medicationsSurgery:
VSD closurePlacement of conduit between the right ventricle and pulmonary arteries.
Total anomalous pulmonary venous pressure
Continuous murmurHyperactive right ventricular impulseWidely split S2Ejection systolic murmur at the left upper sternal border
Open and ligation
CASE STUDY
A 5-hour old newborn on the postnatal ward is noticed by the midwife because he looks blue around the lips and tongue. He is the first child of a 7y/o mother with asthma who was taking inhaled steroids throughout pregnancy. Antenatal scans were unremarkable. She went into spontaneous labour 41weeks and there was thin meconium staining of the liquor when the membrane ruptured 1hour before delivery. CTG monitoring during labour revealed normal variability of fetal heart rate. The baby was born by oral vaginal delivery and weighed 3.3kg. The Apgar scores were 7 at 1 min and 8 at 5 min.
Examination: the baby is dysmorphic. His temperature is 36.60C and his central capillary refilling time is 2s. His lip, tongue and extremities are cyanosed. He is crying normally and no signs of increased respiratory effort. Heart rate is 160 bpm., femoral pulses are palpable, heart sounds are normal and no murmur audible. Oxygen saturation is 70% in air and does not rise with facial oxygen, which has been administered by midwife. There is no hepatosplenomegaly.
MurmursDefect Characteristic
ASD −Ejection (mid) Systolic murmur(3rd L i/c space)−Rumbling mid diastolic murmur (lower L sternal edge) in larger shunt−Grade I or II
VSD −Physiologic splitting of S2 is usually retained.−The characteristic harsh, holosystolic murmur is loudest along the lower left sternal border (LSB), and it is well localized. Small defects can produce a high-pitched or squeaky noise.
-The holosystolic murmur; less harsh, more blowing in nature and even is less likely to be audible in the newborn period. -Pulmonic component of the 2nd heart sound may be increased as a result of pulmonary hypertension.
PDA −Continuous−At left infraclavicular area−Radiates along pulm arteries, well heard at the back−Larger shunt; Mid diastolic murmur
Aortic Stenosis
−Systolic−R 2nd intercostal space, along sternum−Radiate to neck
Coarctation of aorta
−Ejection systolic−Left intrascapular area of the back−Continuous murmur through out chest if significant collateral developed
Normal*