This is the commonest congenital cyanotic heart disease in adults. Many children with congenital cyanotic heart disease cannot survive beyond neonatal period. Transposition of great vessels is more common in neonatal period but is usually fatal. This defect consist of pulmonary stenosis inter-ventricular septal defect right ventricular hypertrophy and dextroposition of the aorta. Overriding the ventricular septum.
FRETURES OF FALLOT’S TETRALOGY
Dyspnoea and fatigue.
Severe cyanotic spells (Fallot’s tetralogy spells) occur and the child assumes a squatting position to get relief from it.
Central cyanosis is always present in servere cases. It is absent in mild cases (acyanotic fallot’s). the disease is detected at birth by cyanosis (blue baby).
Cyanosis always occurs after exercise and when baby cries. Clubbing of fingers and toes is present except in mild cases.
5.In mild acyanotic cases there is long loud pansystolic ejection murmur arising from VSD. With degree of severity, the ejection murmur also varies in intensity. When there is sever pulmonary stenosis or no murmur is heard. A continuous murmur due to bronchial collacterals or blood flow through PDA can be heard usually on the back.
No peresternal lift, so-called silent precordium is present.
single and loud second heart sound (A2) rarely associated with Aortic ejection click. p2 is very faint delayed with mild cyanosis and inaudible with sever cyanosis. Pulmonary stenosis is shorter and softer. Aortio diastolic murmur may be heard.
pulse volume is normal; venous is normal. Right ventricular thrust is very minimal. So heart is quite.
X-ray of chest show oligaemia of the lund fields and boot- shaped heart due to right ventricular hypertrophy with absence of pulmonary conus (Coeur en sabot).
ECG shows moderate right ventricular hypertrophy with right axis deviation which is the rule.
two-dimensional Echocardiogram is particularly helpful for the diagnosis. With Doppler, the flow across VSD can be seen and the diagnosis can be established. RVOTO is best assessed by two-dimensional echocardiogram and Doppler study.
Cardiac catheterization is required before operation to find out the pulmonary pressure, to show that aortic and right ventricular pressure are same and to see the exact site of outflow obstruction. Angiography is also required for the detailed anatomic defect.
HAEMATOCRIT: polycythemia varies with the degree of hypoxia.
complications include pulmonary or cerebral thrombosis due to polycythemia, paradoxical cerebral embolism leading to cerebral abscess, infective endocarditis.
TREATMENT OF FALLOT’S TETRALOGY:
Palliative surgery includes Blalock_Taussig operatiom (anastomosis of subclavian and pulmonary artery), pott’s operation (anastomosis of descending aorta and the left pulmonary artery), Waterston operation (anastomosis of ascending aorta and right pulmonary artery). In all such procedure blood flow to the lungs can be increased.
COMPLATE REPAIR OF FALLOT’S TETRALOGY
This is the treatment of choice and is indicated in adults patients.Prostaglandins are OGY: used IV to keep the ductus patent. For cyanotic spells Propranolol may be used.