Congenital Heart Disease

Subsets: (see also notes below)

• Cyanotic heart disease - presenting in the newborn or in the older child
• Neonatal cardiovascular collapse due to structural heart defects
• Structural defects causing heart failure
• Asymptomatic murmurs

Important points in the history

• Cyanosis
  • When was it first noted?
  • Is it present at all times?
  • If not, what brings on a spell? Does child squat?
• Other cardiac symptoms:
  • e.g. breathlessness on feeding or exertion; easily fatigued,
  • sweating, failure to thrive
  • Past Medical history that suggests cardiac disease may be acquired rather than congenital
    e.g. previous illness suggestive of rheumatic fever or HIV
  • Symptoms pointing to non-cardiac pathology (eg. respiratory disease)
    • e.g. fever and cough; signs of immunosuppression (?PCP)

Important points on examination

• Dysmorphic? (e.g. Downs, Turners, Noonans)
• Cyanosis/oxygen saturation; clubbing (suggests longstanding cyanosis)
• Pulse rate and volume; BP; Femoral pulses present? Any radio-femoral delay? Peripheral perfusion
• Location apex beat. Heart sounds/ murmur
• Respiratory rate and effort; added sounds on auscultation
• Hepatomegaly and peripheral oedema
• Bulging chest (usually the left hemithorax; mainly older children)

Relevant investigations

• PCV - polycythaemia may indicate longstanding cyanosis
• Echocardiogram - if structural heart disease suspected
• CXR - if structural heart disease suspected
• ECG - useful in selected cases, if available
• Hyperoxia test- - for cyanotic newborns- give 100% O2: if baby remains blue or oxygen saturations fail to rise more than 10%, suggests CHD

Indications for admission

• Cyanosis - in general any child with acute cyanosis must be admitted.(Exception if child has longstanding cyanosis and already been investigated)
• Any evidence of acute cardiac failure or cardiovascular collapse.
• An otherwise well child with a heart murmur may be referred to cardiac clinic.

NOTES FOR SPECIFIC SUBSETS OF CONGENITAL HEART DISEASE:

(a) Cyanotic congenital heart disease presenting as cyanosis in the newborn

Cyanosed term infant who does not pink-up with oxygen. He/she may or may not have other cardiac signs such as a cardiac murmur, and may appear otherwise well.

Note: Cyanotic congenital heart disease may be difficult to distinguish from persistent pulmonary hypertension of the newborn (PPHN) due to persistent foetal circulation.
Suspect PPHN if there has been foetal distress, the need for resuscitation at birth, or neurological signs of birth asphyxia.

Management

• Investigate with chest X-ray and/or echocardiogram.
• Parental counselling re: condition and prognosis (generally poor in Malawi)
• Rx PPHN with oxygen, minimal handling, consider iv Magnesium infusion

(b) Congenital heart disease causing neonatal collapse

Baby presents in shock/ state of collapse in the first 2 weeks after patent ductus shuts.
These babies are difficult to distinguish clinically from those with collapse from other causes eg. sepsis/ inborn errors of metabolism.

Management

Prostaglandins to maintain the patency of the ductus arteriosus as a temporary measure are not available. The surgery that would be required following this is also unavailable in Malawi.

• Treat for septic shock - correct hypoglycaemia and hypothermia until cardiac diagnosis established
• If there is a clear deterioration with administration of oxygen, stop it.
• Consider furosemide if clear signs of cardiac failure present (see chapter cardiac failure).
• Counsel the parents

(c) Cyanotic congenital heart disease presenting as cyanosis in the older child

• Usually Tetralogy of Fallot, associated with hypercyanotic spells.
• Characteristic squatting behaviour relieves cyanosis and breathlessness during spell

Management of spell

• Place the child in knee-chest position (or encourage squatting in older child)
• Give oxygen
• Give i.v. or i.m. morphine 0.1mg/kg and p.o. propranolol 0.5mg/kg STAT
• Give maintanance fluids to increase venous fill

Long-term Management of TOF

• Propranolol 1mg/kg BD to prevent spells
• Aspirin if polycythemic
• Suitable for referral to South Africa if available (discuss with consultant cardiac clinic)

(d) Congenital heart disease causing cardiac failure

• Large ventricular septal defect (over 5mm)
• Atrio-ventricular septal defect (rarely ASD)
• Large persistent ductus arteriosus
• Coarctation of the aorta (clue: absent/very weak femoral pulses)
• Significant pulmonary or aortic stenosis
• Hypoplastic left heart

Management

• Manage cardiac failure as per protocol
• Refer to cardiac clinic (Tuesday 09:00)
• Consider referral for surgery in RSA if child has not developed pulmonary hypertension.
  Patent ductus arteriosus can often be closed surgically in Malawi

(e) Asymptomatic murmurs

• Innocent murmur (which may become more prominent with the relative tachycardia of
  intercurrent illness).
  • These children have a normal heart. They are asymptomatic. Innocent murmurs are soft, localised, systolic, and may vary with posture. CXR normal.
  • Reassure parents

• Pathological murmur loud, pansystolic, diastolic, cyanosed, abnormal CXR
  • Refer to Cardiac clinic (Tuesdays 9:00 am)

Some general points for children with structural heart disease:

• Antibiotic prophylaxis against bacterial endocarditis when undergoing dental treatment or any
  surgery (50 mg/kg Amoxicillin PO 1h pre-OP and 7.5mg/kg Gentamycin IM/IV STAT)
• Referrals to RSA or India can be made by consultant in cardiac clinic via letter to QECH external referrals committee.
• Children with uncorrected structural heart defects may need referral to the Palliative Care Team for support and assistance with symptom control.