Congenital heart disease

• Causes of congenital heart disease:

  • Chromosomal abnormalities
  • Maternal disorders
  • Maternal drugs
• Chromosomal abnormalities:

  • Down's syndrome (trisomy 21)
  • Edwards syndrome (trisomy 18)
  • Patau syndrome (trisomy 13)
  • Turner syndrome (45X0)
• Maternal disorders:

  • Rubella infection in pregnancy
  • SLE
  • Diabetes mellitus
• Maternal drugs:

  • Warfarin
  • Alcohol
• Breathless baby - left to right shunts (oxygenated pulmonary venous blood returns directly to the lungs)

  • Ventricular septal defect (VSD)
  • Atrial septal defect (ASD)
  • Patent ductus arteriosus
• Blue baby - right to left shunts (cyanotic)

  • Tetralogy of fallot
  • Transposition of the great arteries
• Breathless and blue baby - common mixing

  • Atrioventricular septal defect (complete)
• Outflow obstruction in a well child

  • Pulmonary stenosis
  • Aortic stenosis
• Outflow obstruction in a baby collapsed with shock

  • Coarctation of the aorta
• Murmurs:

  • Vast majority of children who have murmurs have a normal heart
  • Innocent or flow murmurs tend to be heard during a febrile illness or anaemia
  • Features of innocent murmur = soft, short, systolic, symptomless, situational dependent (gets quieter when standing or only appears when child is unwell)
  • If in doubt arrange review by paediatric cardiologist for echo
• Concerning murmur features:

  • Murmur louder than 2/6
  • Diastolic murmurs
  • Louder on standing
  • Other symptoms, such as failure to thrive, feeding difficulty, cyanosis or shortness of breath
• Acyanotic cardiac lesions:

  • Ventricular septal defects (VSD)
  • Atrial septal defects (ASD)
  • Patent ductus arteriosis (PDA)
• Features of acyanotic cardiac lesions:

  • Left to right shunting - mixing of oxygenated blood with deoxygenated blood
  • Increased pulmonary blood flow - risk of pulmonary hypertension and if untreated can lead to Eisenmenger syndrome - pulmonary pressure increases beyond systemic pressure, leading to right to left shunt and cyanosis
  • Lesions above the level of the nipple usually cause ejection systolic murmurs
  • Lesions below the level of the nipple usually cause pan-systolic murmurs
• Cyanotic lesions (6Ts)

  • Occur due to the mixing of deoxygenated blood with oxygenated blood (right to left shunt)
  • 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
• Murmurs:

  • VSD = pan-systolic murmur heard loudest at the left lower sternal border
  • ASD = mid-systolic, crescendo-decrescendo murmur loudest at the upper left sternal border. There is a fixed split second heart sound.
  • PDA = continuous crescendo-decrescendo 'machinery' murmur, heard loudest below the clavicle