CONGENITAL HEART DISEASE

Dr Siti Aisyah Abd MajidFamily Medicine Trainee, PPUKM

Objectives• Recognise the various presentations and causes

of congenital heart conditions at birth, during infancy and childhood period

• Manage and follow-up congenital heart conditions in children

• Refer appropriately children with congenital heart diseases to the Paediatrician

OVERVIEW• Congenital heart disease (CHD) – the most

common congenital disorder in newborns (6-21 per 1000 live births).

• In preterm infants 2-3 times greater than term infants

• One of the leading causes of perinatal & infant death from congenital malformations.

(UK Northern Congenital Abnormality Survey)

Anatomy of the heart• 4 chambers

o RA, RVo LA, LV

• 4 valveso Mitral / bicuspido Tricuspido Aortico Pulmonary

Anatomy of the heart• 5 great vessels

o SVC, IVCo Pulm arteryo Pulmonary veino Aorta

• Deoxygenated bloodo From SVC + IVCo RA, RVo Pulm artery lungs

• Oxygenated bloodo From pulm veino LA, LVo Aorta systemic circulation

Fetal circulation• In utero, placenta

acts as the lungs, therefore less blood passes into the actual fetal lungs.

• 2 structures within a fetal heart that allow this "bypass“o Patent ductus

arteriosuso Foramen ovale

Fetal Circulation• PFO is a hole between

the two atriums. It allows mixing of blood between the two right and left atrium.

• PDA allows mixing between the pulmonary artery and the aorta as it is a passageway between these two major vessels.

Fetal Circulation

• This change in the pressures allows more blood to flow into the lungs.

• The changes in pressure cause the PDA and PFO to eventually close.

• The final closure usually takes several days.

• The pressure in the lungs of a fetus is higher than that in the body.

• This increased pressure encourages the right to left shunt.

• After a baby is born the pressure in the lungs decreases as the vessels in the lungs begin to relax.

AHA Classification of CHD Septal defects

ASD

VSD

Obstructive defects

AS

PS

COA

Cyanotic defects

TOF

TGA

Tricuspid atresia

Pulmonary atresia

Truncus arteriosus

TAPVC

HLHS

ASD• Opening in the atrial

septum permitting free communication of blood between the atria.

• 10% of all CHD

• Hemodynamics:o Lt Rt shunto Increased blood flow into

RA enlarged RA + RVo Pulm HPT

VSD• opening in the

ventricular septum, which allows free communication between the Rt & Lt ventricles.

• 20 to 25% of all CHD

• Hemodynamics:o Lt Rt shunto Increased blood flow into RV

enlarged RVo Pulm HPT

Aortic Stenosis (AS)

Aortic Stenosis (AS)

• 5 percent of all CHD.

• Narrowing of the aortic valve.

• Depending on the severity of the stenosis, the symptoms at birth can vary from none to decreased blood flow and decreased oxygenation to the systemic circulation

Pulmonary Stenosis (PS)

• 5-8% of all CHD.

• Narrowing of the pulmonary valve.

Hemodynamics:• RV pressure hypertrophy

RV failure.• RV pressures maybe >

systemic pressure.• Post-stenotic dilation of

main PA.• W/intact septum & severe

stenosis R-L shunt through PFO cyanosis.

• Cyanosis is indicative of Critical PS.

Coarctation of Aorta (COA)

• an obstruction to the outflow from the left ventricle at or near the aortic valve that causes a systolic pressure gradient of more than 10mmHg.

• 7% of CHD.

3 Types• Valvular – Most common.• Subvalvular(subaortic) – involves the

left outflow tract.• Supravalvular – involves the

ascending aorta is the least common.

Hemodynamics:• Obstruction of left ventricular outflow

pressure hypertrophy of the LV.

Tetralogy of Fallot (TOF)

TOF1. Stenosis of the pulmonary artery2. Interventricular communication3. Deviation of the origin of the aorta to the right4. Hypertrophy, almost always concentric in type,

of the right ventricle. Failure of obliteration of the foramen ovale may occasionally be added in a wholly accessory manner

Fallot, Ètienne-Louis-Arthur. Contribution to the pathologic anatomy of morbus caeruleus (cardiac

cyanosis). Marseilles Med. 1888; 25:418-20.

Transposition of Great Arteries (TGA)

TGA• 5% of all CHD

• The aorta is connected to the right ventricle (rather than the left), so instead of pumping blood to the lungs it pumps it back to the body. On the left side of the heart the pulmonary artery is connected to the left ventricle which pumps the blood that returns from the lungs back to the lungs.

• There are two separate circuits at work. One handles and recirculates the unoxygenated blood from and to the body; the other handles and recirculates the oxygenated blood from and to the lungs.

• These babies need the PFO and PDA to remain open so there is mixing of oxygenated blood with unoxygenated blood.

Tricuspid Atresia

Tricuspid Atresia• Atresia = blocked

• Right atrium is unable to allow blood flow into the right ventricle because the tricuspid valve is blocked.

• Since the right ventricle has not been working, it becomes smaller in size and underdeveloped. This defect may be seen with a single ventricle, which means instead of a left and right ventricle there is just one large ventricle.

• The survival of an infant with tricuspid atresia is dependent on communication between the right and left atriums via an ASD, VSD or PFO.

Pulmonary Atresia• <1% of all CHD

• PA + VSD = a feature of TOF

• PA + no VSD = hypoplastic right ventricle

• The PFO allows mixing of unoxygenated blood from the right to mix with oxygenated blood on the left.

• The PDA or patent ductus arteriosus (also a normal fetal structure) also allows for mixing of blood, which provides a means to get blood to the lungs after the baby is born.

Truncus Arteriosus

Truncus Arteriosus• <1% of all CHD

• Combination of the aorta and pulmonary artery into one large arterial vessel rather than two.

• This large, single vessel usually sits above a large VSD, a/w valve abnormalities.

• The result of the common aorta and pulmonary artery is unrestricted left to right shunting which cause congestive heart failure (CHF).

Total Anomalous Pulmonary Venous

Connection (TAPVC)

• 1% of all CHD

• Some or all of the pulmonary veins are abnormally connected and drain into the right atrium.

• These babies are dependent on the fetal circulation remaining intact after delivery. Blood passing through the PFO allows for filling of the left atrium.

• The oxygen rich blood in the pulmonary veins mixes with the oxygen depleted blood normally found in the right atrium. This is the blood that flows into the left atrium. From the left atrium the blood goes into the left ventricle and is then pumped to the body via the aorta. The mixed blood that is pumped out through the aorta to the body is usually quite low in oxygen.

Hypoplastic Left Heart Syndrome (HLHS)

• 1 to 2 percent of all CHD.

• With this syndrome the left side of the heart is smaller than normal. The structures affected can include the left ventricle, the mitral and aortic valve, as well as the aorta. These babies are dependent on the fetal circulation remaining intact after delivery.

• For oxygenated blood to reach the body the right ventricle pumps the blood into the pulmonary artery and some of this blood passes through the PDA (patent ductus arteriosus) into the aorta and eventually to the body

Critical CHD• CHD requiring surgery or catheter based

intervention in the 1st year of life.

• High risk of mortality & morbidity when there is delay in Dx & referral to tertiary centre.

• 25% of those with CHD

• Timing of presentation:o At birth – presents with serious life-threatening

clinical findings immediate interventiono After discharge – diagnosis missed prior to

discharge as the infants appear normal on routine examination, esp in ductal dependent lesions

• Ductal dependent lesions• Coarctation of aorta• Interrupted aortic arch• Aortic stenosis• HLHS (hypoplastic left heart syndrome)• TGA (transposition of the great artery)• Trunsus arteriosus• TOF (Tetralogy of Fallot)• Total anomalous pulmonary venous connection

Presentations at birth• No symptoms

• Shock

• Cyanosis – detected when the concentration of reduced Hb is 4-5g/dL

• Severe pulmonary oedema resulting in tachypnoea & increased work of breathing

History• Maternal DM and/or obesity increase the risk of CHD• Smoking in the 1st trimester• Congenital infx – CMV, herpesvirus, rubella,

coxsackie• Drugs – hydantoin, lithium, alcohol• ART (assisted reproductive therapy)• Family Hx

o Cardiomyopathies, sudden death, unexpected death in infancy

o 3x increased risk of CHD when 1st degree relative has CHDo 15.2x for monozygotic twin

Physical examination• General

o Cyanosiso Pulse oxymetry screening (SpO2)o Tachypnoeao Coughing & wheezingo Peripheral arterial pulseso Extracardiac abnormalitieso Hyperoxia test

Physical examination• CVS

o Abnormal heart rateo Thrillo S2 splittingo Other heart soundso Murmurs (innocent / pathologic)

*** Absent of murmurs does not rule out CHD• The velocity of turbulent blood flow may not be high enough to

generate a murmur• Decreased ventricular function can limit generation of murmur• Elevated pulmonary resistance may limit flow may not be

sufficient to be audible until the resistance has fallen

Later presentationSIGNS

• Central cyanosis• Pallor• Murmurs• Diminished or absent

peripheral pulses (in COA)

SYMPTOMS

• Difficulty in feeding• Limited milk intake• Feedings take too long• Frequent disruption of sleeping• Choking, gagging• Vomiting• Changes of colour (pallor,

central cyanosis)• Excessive unexplained

irritability• Excessive sweating (with

feeding)• Poor weight gain• Inactive, excessive sleeping

Presentations - infancy• Poor feeding• Lethargy & tiring with early stopping of feeds• Respiratory distress – tachypnoea, wheezing• Trouble coordinating feeding & breathing• Irritability• Sweating while feeding• Poor weight gain (decreased caloric intake because

of poor feeding & increased metabolic demands because of the underlying cardiac disease

• Grunting (low-pitched sound generated when the infant closes the glottis)

• Hypoxemic spells (“tet spells”) are one of the hallmarks of severe tetralogy

• Tet spells most commonly start around 4 to 6 months of age and are characterized by:o onset or deepening of

cyanosiso Sudden onset of dyspneao Alterations of consciousnesso Decrease in intensity of

systolic murmur

Presentations - children

• Non-specific symptomso Inability to keep up with peerso Respiratory distresso Sweating (diaphoresis) esp with exertiono Poor weight gain

• Chest paino Severe & crushing pain – radiates to arm/jaw

Cardiac ischemiao Retrosternal sharp, severe & constant pain –

radiates to Lt shoulder pericarditiso Severe, sharp & tearing pain – radiates towards the

back btwn scapulas dissecting aneurysmo Exertion-induced chest discomfort coronary

heart disease or hypertrophic cardiomyopathyo Chest pain a/w syncope or palpitation

tachyarrhythmias

• Fevero Endocarditis – need to be considered in a

febrile pt with a new or changing heart murmuro Rheumatic fever – a sequela of group A

streptococcal pharyngitis, can present with myocarditis or pericarditis

o Kawasaki disease – should be considered in child with fever > 5 days, particularly if it is accompanied with rash, lymphadenopathy, conjunctivitis & distal extremity changes. The majjor complication coronary artery aneurysm

Family History• Infant risk of CHD with affected parent (AVSD or TOF)

4%• Infant risk of CHD with an affected sibling 2%

Burn J, Brennan P, Little J, et al. Recurrence risks in offspring of adults with major heart defects: results from first cohort of British collaborative study.

Lancet 1998; 351:311

• Other heart diseases that have familial predisposition:o Family dilated cardiomyopathyo Hypertrophic cardiomyopathyo Familial causes of sudden cardiac death (long QT syndrome)

Physical findingsGENERAL

• Tachycardiao Causes: arrhythmia (SVT, VT), heart failure, Lt to Rt shunt

diseaseo ECG is helpful in evaluating cause of tachycardiao Tachyarrhythmia - Require urgent referral, risk for

potentially life-threatening cardiac disease

• HPTo Need to rule out COA

• Failure to thriveo Due to inadequate food intake, increased metabolic

demandso Suggestive of cardiac cause if child easily tired while

feeding, have Sx of respi distress, murmurs+

• Poor perfusion – due to low cardiac outputo CRT > 3 secso Cool extremitieso Decreased peripheral pulseso May lead to shock / impending shock

• Febrile – as mentioned

RESPIRATORY ABNORMALITIESo Wheezing – primary pulmonary disease,

cardiac disease a/w elevated Lt venticular end-diastolic pressure, pulm HPT

o Tachypnoea due to:a) Increased pulmonary blood flow / pulm venous congestionb) Elevated Lt ventricular end-diastolic pressure

o Rales – heart failure, pulmonary overcirculationo Stridor – due to airway obstruction, caused by

congenital vascular anomaly eg vascular ring

• CVS – FINDINGS THAT WARRANT REFERRAL TO CARDIOLOGIST

FINDINGS NATURE DIAGNOSIS

Loud murmur, grade 3 or higher

** intensity less than Garde 3 usually innocent / functional murmurs

Harsh murmur ESM @ upper Lt sternal border

Pulmonary stenosis

ESM @ upper Rt sernal border

Aortic stenosis

Continuous murmur PDA

Pansystolic murmur PSM @ Lt sternal border

VSD

FINDINGS NATURE DIAGNOSIS

Diastolic murmur

Loud or single S2 Loud S2 Pulmonary HPT

Widely split S2 ASD

Gallop rhythm Constant 3rd heart sound

Cardiomyopathy, AV incompetent valves, L-R shunt disease

Friction rub Sandpaper-like sounds

Pericarditis

• Innocent / functional murmurs o Majority murmurs in infants/childreno Due to turbulence across the branch pulmonary arteries

that are not fully developed because of the relatively small amount of pulmonary blood flow in utero

o Typically disapears by 6 months of age increase in size of the branch pulmonary arteries reduction in turbulence

• Characters:o a/w quiet precordiumo a/w normal S2o Crescendo-decrescendo patterno Intensity < Grade 3o Asymptomatic child

MANAGING CHILDREN WITH CHD IN PRIMARY CARE

• Developmental issues• Feeding & growing• Medications• Immunization• Infective endocarditis prophylaxis

Developmental issues• Causes:

o Chronic diseaseo Genetic causeso On cardiopulmonary bypass

• Denver II test – screen for cognitive & behavior in 4 developmental domains

• 1/3 of children with CHD who required surgical or catheter intervention have GM, FM and social skills delay. (Weinberg et al, 2001)

• School-aged children with hx of newborn cardiac surgery for complex CHD are at increased risk of inattention and hyperactivity (Shillingford et al, 2008)

Feeding & Growing• Infants with complex CHD often experience poor

nutritional status due to poor feeding (Jadcherla et al, 2009)

• Parents complaints: Longer to feed, poor appetites, refuse to eat

• It is important to plot the weight & length/height at every visit

• Breastfeeding: should be encouraged as long as there is weight gain

• May consider to fortify with formula milk to make it 24-30 calories/oz

• Enteral feeding: can be initiated through nasogastric tubes in infants who fail to gain weight despite being fed with fortified formula

• Red flag:o Growth below 5th centileo Weight become disproportionate to their heighto Rate of weight gain is < 25% than the expected findings

Medications• To ensure the child take medications before and after the

surgery

• Should inquire the use of over-the-counter medication and check the interaction with current cardiac medications

• Monitor if there are signs of renal insufficiency or drug toxicity to notify the cardiologist

• Adjustment of drug doses because of wt gain also should be done in consultation with paediatric cardiologist

Immunization• Immunization record should

be reviewed

• DiGeorge syndromeo Caused by deletion of

22q11.2o Result in immunocompromiseo Associated cardiac defects -

TOF, interruptud aortic arch, truncus arteriosus, pulmonary atresia

o Immunology consultation is needed before the administration of live vaccines

• Spleen – provides primary immunologic defense by being a reservoir for T lymphocytes that initiate the production of IgM (first Ab produced in infection)

• Asplenic pt – should take prophylactic antibiotics & should receive all their scheduled immunizations (Price et al, 2007)

• AAP recommends that prophylactic antibiotics be discontinuedat 5 years of age, provided the child has not had pneumococcal infx & has received pneumococcal immunizations. (AAP Committee on Infectious Disease, 2000)

IE Prophylaxis• American Heart Association (AHA) recommends

maintaining oral health & hygiene with regular brushing, flossing and dental visit since age 1 year old

• Prophylactic antibiotic prior to dental procedure are limited to children with:o Artificial heart valveso Prev Hx of IEo Serious CHDo Cyanotic heart disease

APPROPRIATE REFERRAL

•URGENT o In pt with or at imminent risk for hemodynamic compromise &

deatho Cardiogenic shock, central cyanosis, tachyarrhythmias,

syncope

• TIMELYo In pt with a suspected cardiac condition that may

progress & has the potential to result in hemodynamic compromise, significant morbidity & become life threatenning over a period of weeks / months

o Referral should not be more than a week

o Eg: VSD, PDA, TOF

• ROUTINEo Pt with potential cardiac lesions that is unlikely to

proceed to hemodynamic compromise and can over a matter of weeks

o Eg: asymptomatic patient with a loud non-innocent murmur.

Summary• Children with CHD can present a challenge to

primary care practitioners

• May require more focused attention on regular visits for health maintenance & prevention of illness

• Timing of referral is based upon the risk the underlying suspected cardiac disease may progress & causing hemodynamic compromise, morbidity & mortality

THANK YOU