What is aortic stenosis?
The aortic valve controls blood leaving the left ventricle to the rest of the body. When it is narrowed, the heart's main pumping chamber has to generate extra pressure to push blood through it — over time, this can thicken and strain the heart muscle.
In a newborn, severe aortic stenosis is a medical emergency, since the body may not get enough blood flow. In an older child, it is more often mild and found on routine examination, needing careful watching rather than urgent treatment.
Signs that may point to it
How it is diagnosed and treated
Echocardiography measures the valve's narrowing and the pressure gradient across it, and is central to deciding whether treatment is needed now or watching is appropriate.
Balloon aortic valvuloplasty — widening the valve by catheter — can relieve significant narrowing at any age, including as an emergency in a critically unwell newborn. Because the aortic valve carries the body's full output for a lifetime, children who have had this valve treated are followed closely, often into adulthood, since some go on to need further treatment years later.