Congenital Heart Disease: common mixing Flashcards
Which conditions are known as ‘blue and breathless’
AVSD (complete)
Complex congenital heart disease (e.g. tricuspid atresia)
Outline complete AVSD
Most commonly seen in children with Down syndrome
- Defect in the middle of the heart with a single five-leaflet valve across the entire atrioventricular junction and tends to leak
- The large defect leads to pulmonary hypertension
Features of complete AVSD:
- Present at antenatal USS screening
- Cyanosis at birth or heart failure at 2-3 weeks
- NO murmur heard, lesion detected on Echocardiography
- Always a superior axis on the ECG
MANAGEMENT: treat heart failure medically and surgical repair at 3-6 months
Outline tricuspid atresia
In this condition, only the left ventricle is effective.
The right ventricle is small and non-functional
This is due to complete absence of the tricuspid valve
Presentation of tricuspid atresia
- Common mixing of systemic and pulmonary venous return in the left atrium
- Cyanosis in the newborn period if duct-dependent
- The child may be well at birth and then become cyanosed or breathless
- Ejection systolic murmur- loudest at the left upper sternal edge
- Prominent apical impulse
Management of tricuspid atresia
Early palliation to maintain a secure supply of blood to the lungs at low pressure by:
- Blalock-Taussig shunt insertion – between the subclavian and pulmonary arteries
- Pulmonary artery banding operation- to reduce pulmonary blood flow if breathless
IMPORTANT: complete corrective surgery is NOT possible in most cases because there is only one functioning ventricle
Operations can be performed to:
- Connect the SVC to the pulmonary artery (Glenn or Hemi-Fontan)- after 6 months of age
- Connect the IVC to the pulmonary artery (Fontan) – at 3-5 years
Thus, the left ventricle drives blood around the body and systemic venous pressure supplies blood to the lungs.
The Fontan procedure helps relieve cyanosis and removes the long-term volume load on the single functional ventricle.
