The congenital cardiac abnormalities that are associated with cyanosis involve shunting of blood from the right side of the heart to the left side. These include the following cardiac abnormalities:
- Tetralogy of Fallot
- Pulmonary atresia with ventricular septal defect (VSD)
- Transposition of the great vessels
- Truncus arteriosus (associated VSD is always present)
- Eisenmenger syndrome
- Hypoplastic left heart syndrome
Those abnormalities manifesting in the neonatal period have a poor prognosis.
TETRALOGY OF FALLOT
This is the commonest of the cyanotic group because of a slightly better prognosis in infancy, allowing more of them to survive longer.
Classically, Tetralogy of Fallot consists of;
- Pulmonary stenosis
- Ventricular septal defect
- Dextroposition of the aorta
- Right ventricular hypertrophy.
sSpecific Clinical Features
- Cyanosis is a major feature. It may not be present at birth, but develops later during first year.
- Other features include dyspnoea on exertion, to which the affected child responds by assuming a squatting position for a few minutes after such an exercise.
- Affected children also tend to have paroxysmal hypercyanotic attacks often referred to as
- The pulse may be normal but a systolic thrill is felt along the left sternal border in 50% of cases.
- Clubbing of fingers and toes occurs after a long time.
The following complications are associated with Tetralogy of Fallot:
- Cerebral thrombosis due to polycythaemia,
- Brain abscess (usually after 2 years of age) presenting with headache, fever, nausea and vomiting with or without seizures,
- Bacterial endocarditis
- Congestive heart failure.
- Full blood count or haematocrit
- CXR – Boot shaped heart oligaemic lung fields
- Blood culture if suspect endocarditis
- CT scan if cerebral thrombosis or abscess is/are suspected
- For children with
bluespells, administer oxygen; child should be in kneechest position.
- Prevent/correct dehydration in these children at all times.
- Provide supportive therapy:
- Venesection: Maintain haematocrit at 55–65% but avoid iron deficiency.
- Intravenous or oral propranolol.
- Refer all children to a specialist unit for definitive treatment by interventional closed repair or open heart surgery.