Chapter 29

    This malformation belongs to the "hypoplastic left heart syndrome" which accounts for approximately 4% of the congenital malformations. Aortic valve atresia is a relatively rare disease which usually determine death in the first few weeks of life.
    Patients are usually small for their gestational ages and present with tachypnea, tachycardia, palpable right ventricle and cyanosis. Atrial gallop and systolic murmur transmitted to the back with absent peripheral pulses is typical with moderate to marked pulmonary congestion.
    The electrocardiogram will show marked right axis deviation with signs of right ventricular hypertrophy.
    The roentgenogram will depict normal or enlarged heart with right ventricular preponderance.

TYPES OF ATRESIA OF AORTIC VALVE

Type I A		Normal intraventricular septum		Atresia of mitral valve
Type I B		Normal intraventricular septum		Normal of mitral valve
Type II A		VSD		Atresia of mitral valve
Type II B		VSD		Normal of mitral valve

    Probably more than 90% of these patients belong to Type I. The recognition of Type II and particularly Type II B is important since successful surgical correction is many times possible.
    The degree of right ventricular preponderance, clinically, in ECG and roentgenograms can be helpful in the differential diagnosis. The echocardiogram is thought to be of some value, too.
    Catherization and angiography is the only way to be categorical in achieving a definitive diagnosis, evaluate the patients hemodynamic status and to rule out associated malformations.
    Echocardiogram in aortic atresia shows marked hypoplasiaof the left ventricle. The condition of the mitral valve (sufficient or insufficient) is difficult to be assessed, which makes ultrasound of limited value in this disease.