Investigations identify the aortic narrowing, collateral-related radiographic changes and evidence of left ventricular hypertrophy.
Imaging
•
Cross-sectional imaging, most commonly computed tomography (CT), is the investigation of choice.
•
The chest X-ray is often normal in early childhood.
•
Later chest X-rays may show indentation of the descending aorta, producing the ‘3 sign’, and notching of the undersurfaces of the ribs caused by collaterals.
Ventricular hypertrophy
•
The electrocardiogram may show left ventricular hypertrophy, which can be confirmed by echocardiography.