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This article aims to provide an overview congenital heart disease, including the different types, associated clinical signs, investigations and management. Click here to download a PDF version.


1. Acyanotic lesions

Acyanotic cardiac lesions include:

  • Ventricular septal defects (VSD)
  • Atrial septal defects (ASD)
  • Patent ductus arteriosis (PDA)

 

Acyantoic cardiac lesions have the following features:

  • Left to right shunting, mixing of oxygenated blood with deoxygenated blood
  • Increased pulmonary blood flow → risk of pulmonary hypertension and untreated acyanotic heart disease can lead to Eisenmenger syndrome
  • Lesions that are above the level of the nipple usually give rise to ejection systolic murmurs while lesions below the level of the nipple typically cause pan systolic murmurs

Ventricular septal defect (VSD)

Symptoms

Depends on the size of defect:

  • Small – may be asymptomatic, normal growth
  • Moderate – poor feeding, failure to thrive (FTT), short of breath (SOB)
  • Large – poor feeding, FTT (falls below centiles), SOB, sweaty and pale with feeds

Epidemiology

  • Most common congenital heart lesion (15-20%)
  • Associated with Down’s syndrome (AVSD)

 

 Time of presentation

  • Antenatal diagnosis at 16-18 weeks
  • Presentation at 6-8 weeks
  • Congestive heart failure typically presents after 4-6 weeks
  • Persistent pulmonary hypertension of the newborn (PPHN) may become established by 6-12 months

 

Clinical findings

Palpate:

  • Check for presence of a thrill
  • Might be useful to palpate liver (enlarged in heart failure)

Auscultate:

  • The loudness of a murmur is inversely proportionate to the size of the defect
  • Pan-systolic murmur heard loudest at the lower-left sternal border (LLSB)
  • Typically grade 3-4
  • Loud P2 suggests the presence of pulmonary hypertension

Investigations

  • Pulse oximetry – to determine the level of oxygen saturation
  • ECHO – visualise defect directly
  • CXR – cardiomegaly and pulmonary oedema (increased pulmonary vascular markings) if severe VSD (presence of heart failure), enlarged pulmonary artery

 

  • ECG:
    • In patients with moderate or large VSD, the ECG may demonstrate LV hypertrophy (LVH) manifested as increased voltage in V5 and V6, or leads II, III, and aVF
    • In patients with elevated RV pressure, the ECG demonstrates RV hypertrophy (RVH), often manifested by tall R waves in leads V4R and V1, or upright T waves in these leads beyond the first 24 hours of life, in addition to LVH.

 

Management

  • Small lesion: < 5mm usually close spontaneously, no repair required (30-40%)
  • Moderate lesion:
    • Diuretic therapy (Furosemide and Spironolactone)
    • Feeding with high caloric feeds (Infantrini)
  • Large lesion:
    • Manage as per moderate lesion
    • Optimise weight gain for surgery
    • Schedule for surgery before 12 months to prevent persistent pulmonary hypertension of the newborn (PPHN)

Atrial septal defect

Symptoms

  • Typically asymptomatic
  • Some children will have recurrent chest infections

 

Epidemiology

  • Second most common acyanotic heart lesion (5-10%)

Time of presentation

  • Mean age of diagnosis is 4.5 years from an incidental finding of murmur
  • Symptomatic presentation is usually before age of 40 years with arrhythmias, dyspnoea

Clinical features

  • May also have no auscultatory finding in infants (asymptomatic)

Auscultate:

  • Ejection systolic murmur heard loudest at the upper-left sternal border (ULSB)
  • Widely fixed splitting of the second heart sound (L→ R shunting increases RV filling, thus RV ejection time is increased and pulmonary valve closure is delayed for a significant amount of time after aortic valve closure)

Investigations

  • Pulse oximetry
  • ECHO – visualise defect directly, shows dilated RV and increased RV filling and ejection time
  • CXR – usually no findings
  • ECG – incomplete RBBB

 

Management

  • Most children are asymptomatic and rarely require congestive heart failure (CHF) therapy
  • Spontaneous closure in lesions smaller than 7-8mm
  • Large defects require repair – percutaneous (catheter closure) or surgery using median sternotomy incision

Patent ductus arteriosus

Symptoms

Dependent on the size of the lesion:

  • Small – asymptomatic
  • Moderate – congestive heart failure with failure to thrive (poor feeding)
  • Large – poor feeding, severe failure to thrive, recurrent lower respiratory tract infections
    • Preterm infants may experience failure to wean from ventilation

 

Epidemiology

  • 5-10% of all congenital heart defects
  • Very common in preterm infants

 

Time of presentation

  • Symptoms usually present 3-5 days after birth when the duct begins to close

 

Clinical features

Palpate:

  • Might be useful to palpate liver (enlarged in heart failure)
  • Bounding pulses and wide pulse pressure

 

Auscultate:

  • Continuous machinery murmur typically heard at the upper-left sternal border (best heard below left the clavicle)
  • Check for presence of a thrill at the upper left sternal border

 

Investigations

  • 2D ECHO and Doppler
  • CXR and ECG are less useful in diagnosing PDA

 

Management

  • If preterm – good probability of spontaneous closure
  • If term – less likely to close spontaneously
  • Medical – indomethacin/ibuprofen (not effective in term infants)
  • Surgical – catheter closure or PDA ligation (left lateral thoracotomy incision) when weight is at least 5kg

 


2. Outflow tract obstruction: Coarctation of the aorta

Pathophysiology

Obstruction to the left ventricles outflow tract leads to an increase in left ventricular afterload which causes left ventricular hypertrophy.

Neonates with severe aortic coarctation can develop heart failure.

Epidemiology

Approximately 5% of all congenital heart defects
Associated with Turner’s syndrome (5-15% of girls with coarctation)

 

Time of presentation

Symptoms present 3-5 days after birth when the duct begins to close as the PDA and foramen ovale allows blood to bypass the outflow obstruction

Clinical features

Palpate:

  • Systolic blood pressure is high when measured with BP cuff
  • Absent femoral pulses (do 4-limb BP measurement)
  • Cold extremities (especially feet)
  • Hepatomegaly in heart failure due to severe coarctation

 

Auscultate:

  • Murmur heard at the back between the scapulae

 

Investigations

  • 2D ECHO and Doppler – direct visualisation of defect
  • CXR and ECG are less useful in the diagnosis

 

Management

Medical therapy:

  • Continuous intravenous infusion of prostaglandin E1 to keep the ductus arteriosus open
  • Dopamine or Dobutamine to improve contractility in those with heart failure
  • Supportive care to correct metabolic acidosis, hypoglycemia, respiratory failure, and anaemia that may contribute to or be a consequence of heart failure.

 

Surgical repair:

  • Balloon angioplasty
  • Resection with end-to-end angioplasty
  • Bypass graft
  • Subclavian flap

3. Cyanotic lesions (6 Ts)

Occur due to the mixing of deoxygenated blood with oxygenated blood (right → left shunt).

Differential diagnoses of cyanotic lesions using the 6 ‘T’s are:

  • Tetralogy of Fallot
  • Transposition of Great Arteries
  • Truncus arteriosus
  • Total anomalous pulmonary venous connection
  • Tricuspid valve abnormalities
  • Ton of others – hypoplastic left heart, double outlet right ventricle, pulmonary atresia

Tetralogy of Fallot

Tetralogy of Fallot features the following four abnormalities:

  1. Ventricular septal defect
  2. Overriding aorta
  3. Pulmonary stenosis
  4. Right ventricular hypertrophy

Symptoms

  • Cyanosis
  • Poor feeding
  • Sweating during feeds

 

Epidemiology

  • 7-10% of congenital heart disease

 

Time of presentation

  • During the neonatal period when the patent ductus arteriosus begins to close (Day 3-5)

 

Main clinical findings

  • Cyanotic “tet” spells due to increased RV to LV shunt due to pulmonary stenosis causing RV outflow tract obstruction
  • The murmur may be present due to right ventricular outflow tract obstruction (RVOTO) caused by pulmonary stenosis and not VSD. The murmur is crescendo-decrescendo with a harsh ejection systolic quality, heard loudest over the upper-left sternal angle with posterior radiation.

 

Investigations

  • 2D ECHO and Doppler – to assess location and number of VSDs and severity of RVOTO
  • ECG – shows right atrial enlargement and right ventricular hypertrophy (right axis deviation, prominent R waves anteriorly and S waves posteriorly)
  •  CXR – classic “boot-shaped heart”, with a right aortic arch seen in 25% of patients
  •  Cardiac catheterisation can help further delineate cardiac lesion, particularly helpful for assessing levels of right ventricular outflow obstruction.

 

Management

Neonates with severe cyanosis: prostaglandin infusion to maintain patency of ductus and pulmonary flow until the time of surgical repair

Medical:

  • Tet spells:
    • Knee to chest position to increase systemic vascular resistance and promote blood flow into the pulmonary circulation
    • Oxygen
    • Morphine
    • B-blockers
  • Heart failure: digoxin and loop diuretic (Furosemide)
  • Prophylaxis for endocarditis: antibiotics

 

Surgical repair – Blalock-Taussig shunt


Transposition of the Great Arteries

Pathophysiology

Aorta arises from the RV and pulmonary artery from the LV, resulting in deoxygenated blood from the RV being circulated around the body

 

Symptoms

  • Cyanosis
  • Poor feeding, sweating during feeds

 

Epidemiology

  • TGA accounts for about 3% of all congenital heart disease, and 20% of all cyanotic heart disease
  • Without treatment, 90% will die within the first year of life

 

Time of presenation

  • During neonatal period when the patent ductus arteriosus begins to close (Day 3-5)

 

Main clinical findings

  • Cyanosis
  • Tachypnea
  • Murmur

 

Investigations

  • Fetal ultrasound
  • ECHO
  •  CXR – classic “egg on a string” appearance
  • ECG and cardiac catheterisation is typically not used in the diagnosis of TGA

 

Management

  • Balloon atrial septostomy to increase mixing of the two circulatory systems
  • Arterial switch procedure

4. Innocent murmurs

Types

  • Still’s murmur
  • Venous hum
  • Turbulent flow in the pulmonary artery bifurcation

Epidemiology

25% of full-term neonates have a murmur

 

Features of an innocent murmur (10 ‘S’)

10 ‘S’ of innocent murmur:

  • Soft
  • Systolic
  • Short
  • S1 and S2 normal
  • Symptomless
  • Special test (x-ray and ECG) normal
  • Standing/sitting vary with position
  • Sternal depression

Still’s murmur

A soft vibratory murmur heard over the lower-left sternal border most frequently in childhood when there is normal blood flow and no cardiac lesion.

 

Venous hum

Continuous murmur heard loudest over the clavicles due to venous return from the head and neck, and this varies with position.

Turbulent flow in pulmonary artery bifurcation

A soft ejection systolic murmur caused by turbulent flow in the pulmonary artery (PA) bifurcation as the PA bifurcation and branches are small.