Overview

• Acyanotic (Left-to-Right Shunt) ⇒
  • Ventricular Septal Defects (VSD).

    • Hole in the septum between the two ventricles. Most common congenital heart defect.

    • Aetiology → chromosomal disorders (down’s syndrome, edward’s syndrome, patau syndrome).

    • May be detected in utero during routine 20 week scan.

    • Sx → failure to thrive, features of heart failure (hepatomegaly, tachypnoea, tachycardia, pallor), pansystolic murmur at lower-left sternal edge (LLSE).

      <aside> 💡 VSD = Very Systolic = Pansystolic.

      </aside>

    • Ix → echocardiogram. CXR may show signs of heart failure (ABCDE).

    • Mx → non-pharmacological: spontaneous closure is common (50%). Pharmacological: digoxin (inotrope), diuretics + ACEi (for heart failure). Surgical (3-6 months): should occur earlier to avoid eisenmenger’s (permanent lung damage from pulmonary hypertension and high blood flow).

    • Complications → aortic regurgitation, infective endocarditis, eisenmenger's syndrome, pulmonary hypertension (and subsequent congestive heart failure).

      • Eisenmenger’s Syndrome → occurs when congenital heart defects are untreated. The left-to-right shunt is reversed due to pulmonary hypertension. The reversal generally occurs in teenagers and causes cyanosis, clubbing and right-ventricular failure. This is a serious complication and can need heart–lung transplant or palliation. It is irreversible and can lead to severe cardiac failure.
  • Atrial Septal Defect (ASD).

    • Hole in the septum between the two atria. Defect involving the fossa ovalis in the centre of the atrial septum. (Foramen Ovale → connects right and left atria during pregnancy).

    • Ejection systolic murmur at left sternal edge + fixed splitting of S2.

      <aside> 💡 ASD = A Split Double.

      </aside>

    • Mx → cardiac catheterisation + insertion of occlusive device (usually at 3yo).

  • Patent Ductus Arteriosus (PDA).
    • Connection between pulmonary artery and descending aorta.
    • More common in premature babies, low birth weight, born at high altitude, or maternal rubella infection.
      • More likely to occur in children with hyaline membrane disease and in those with a concurrent cyanotic congenital heart condition.
    • Sx → left subclavicular continuous ‘machinery’ murmur, large volume bounding collapsing pulse, wide PP.
    • Mx → indomethacin or ibruprofen (inhibits prostaglandin synthesis and closes the connection).
  • Coarctation of the Aorta.
    • Congenital narrowing of the descending aorta.
    • Associations → turner’s syndrome, bicuspid aortic valve, berry aneurysms, neurofibromatosis.
    • Features → heart failure in infancy, hypertension in adults. Radio-femoral delay, mid-systolic murmur. Absent or weak femoral pulses.
    • Mx → surgical repair or balloon angioplasty +/- stenting.
• Cyanotic (Right-to-Left Shunt) (TTT) ⇒
  • Tetralogy of Fallot.
    • Most common cause of cyanotic congenital heart disease.
    • Typically presents in first few weeks/months.
    • 4 coexisting pathologies (PROV) → ventricular septal defect (VSD), overriding aorta, pulmonary valve stenosis (causes ejection systolic murmur + right ventricular outflow obstruction determines degree of cyanosis), right ventricular hypertrophy.
      • Presentation → ejection systolic murmur at upper left sternal border due to pulmonary stenosis.
      • Hypercyanotic ‘tet’ spells while crying or feeding.
    • Risk Factors → rubella infection, increased maternal age (>40), alcohol consumption in pregnancy, diabetic mother.
    • Investigations → echocardiogram first line. CXR: ‘boot shaped’ heart due to right ventricular thickening.
    • Management:
      • Initial → maintain PDA with prostaglandin E1 (aloprostadil).
      • Definitive → surgery (6 months later) - BT Shunt.
      • ‘Tet Spells’ → if severe, can be managed last-line with a vaso-constrictive agent (eg. phenylephrine).
  • Transposition of the Great Arteries (TGA).
    • Failure of the aorticopulmonary septum to spiral during septation.
      • Parallel aorta and pulmonary trunk on echo (aorta attached to RV and pulmonary artery attached to LV).
    • Typically presents in first few hours after birth.
    • Children of diabetic mothers are at increased risk.
    • Sx → cyanosis, tachypnoea, loud single S2 (NO MURMURS), prominent right ventricular impulse, ‘egg-on-side’ appearance on CXR.
    • Mx → maintenance of ductus arteriosus with prostaglandin E1 infusion, followed by balloon atrial septostomy to facilitate blood mixing between the atria. Surgical correction (arterial switch operation) is definitive treatment.
  • Tricuspid Atresia.
    • Presents in first few minutes.
    • Absence of tricuspid valve → only left ventricle is functional and RV is not.
      • No blood flow to right ventricle, causing left axis deviation.
    • Causes common mixing of blood in left atrium → cyanosis and breathlessness in first few minutes of life.
    • Mx → surgical intervention.
  • AVSD → down’s syndrome, cyanosis at 2-3w of life (no murmur), found on routine echo.

Making Diagnosis

Clinical Features

• Innocent Murmur → Soft, Systolic, Short, Single, Symptomless, Sternal Edge, Standing/Sitting (vary with position).
  • No radiation. Febrile illnesses can accentuate innocent murmurs (re-review in a few weeks).
  • Venous Hum → due to turbulent blood flow in the great veins returning to the heart. Heard as a continuous blowing noise just below the clavicles.
  • Still’s Murmur → low-pitched sound heard at the lower left sternal edge.

Investigations

• ECHOCARDIOGRAM → any child with suspected congenital heart disease.
• Determining Cause of Central Cyanosis in Neonate → nitrogen washout test (HYPEROXIA TEST). Infant is given 100% oxygen for ten minutes after which an ABG is taken. A pO2 of less than 15 kPa indicates cyanotic congenital heart disease.

Management Plan

• Treatment of Cyanosis in Neonate ⇒
  • A-E Approach → give oxygen.
  • If due to Cyanotic CHD → prostaglandin E1 (alprostadil) infusion. Used to maintain a patent ductus arteriosus until definitive diagnosis is made.

Complications →

Prognosis →