7.congenital heart dss

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*