Aortic Stenosis in Children
When the valve between the heart and the body is too narrow — causes, symptoms, and treatment options.
What Is It
Understanding Aortic Stenosis
The aortic valve guards the exit of the left ventricle — the heart’s main pumping chamber. It opens with every heartbeat to allow blood to flow into the aorta and out to the body, then snaps shut to prevent back-flow.
In aortic stenosis (AS), this valve is abnormally narrow, forcing the left ventricle to generate enormously high pressure to push blood through. Over time, this excess strain causes the left ventricle to thicken and eventually fail.
Types of Aortic Stenosis
| Type | Location | Frequency | Key Feature |
|---|---|---|---|
| Valvar AS | At the aortic valve | ~75% | Bicuspid valve most common; dome-shaped in neonates |
| Subvalvar AS | Below the valve (fibromuscular ring or tunnel) | ~20% | Progressive; can damage the aortic valve itself over time |
| Supravalvar AS | Above the valve in the ascending aorta | ~5% | Associated with Williams syndrome |
Severity Classification
| Severity | Peak Gradient | Symptoms | Management |
|---|---|---|---|
| Mild | <36 mmHg | None | Observe; echo every 1–2 years |
| Moderate | 36–64 mmHg | Possibly none; exertional symptoms possible | Close monitoring; restrict heavy competitive sport |
| Severe | >64 mmHg | Chest pain, syncope, breathlessness on exertion | Balloon valvuloplasty or surgery |
| Critical (Neonatal) | Left heart failure/shock | Pale, shocked newborn with poor pulses | Emergency intervention; PGE1 to maintain circulation |
Signs, Symptoms & the Murmur
Most children with mild-to-moderate AS are completely symptom-free, diagnosed when a murmur is heard on routine examination. Severe AS causes the left ventricle to struggle, producing breathlessness on exertion, easy fatigue, chest tightness, or fainting.
The classic AS murmur: A harsh, crescendo-decrescendo (ejection systolic) murmur heard loudest at the right upper sternal border (aortic area), often with radiation to the neck. An ejection click may precede it. The murmur radiates to the carotids — feel for the characteristic slow-rising, low-volume pulse (pulsus parvus et tardus) in severe cases.
Treatment
Balloon aortic valvuloplasty (BAV) — catheter-based balloon dilation — is used for critical neonatal AS and for symptomatic severe AS in older children when the valve anatomy is suitable. Unlike pulmonary valvuloplasty, BAV is considered a palliative (not curative) procedure, as it often creates significant aortic regurgitation and the valve may re-stenose.
Surgical aortic valvotomy is an alternative to BAV and may be preferred depending on valve anatomy and the surgeon’s expertise.
Aortic valve replacement becomes necessary when palliation fails or when regurgitation from prior procedures becomes severe. Options include mechanical valves (requiring lifelong blood thinners), bioprosthetic valves, and the Ross procedure — where the patient’s own pulmonary valve replaces the aortic valve, and a donor graft replaces the pulmonary valve. The Ross procedure is particularly attractive in children and young adults.
Subvalvar AS is typically managed surgically by resecting the fibromuscular shelf — earlier intervention is recommended because the subvalvar gradient tends to progress and can damage the aortic valve itself.
Not necessarily. A bicuspid aortic valve (BAV) is the most common congenital heart defect, present in 1–2% of the population. Many people with a BAV live their entire lives without significant stenosis. However, a BAV is more prone to calcification and narrowing over time — most commonly in adulthood — and also carries a risk of aortic dilation (enlargement of the aorta). Regular echocardiographic monitoring, usually every 3–5 years in childhood if mild, is standard practice.
Children with mild AS can generally participate in all sports. Moderate AS requires individualised assessment — most non-competitive recreational activities are permitted, but high-intensity competitive sport may be restricted. Severe AS is a contraindication to vigorous exercise because of the risk of sudden cardiac death during exertion. After successful intervention, most children can gradually return to normal activity.
The Ross procedure involves transplanting your child’s own pulmonary valve into the aortic position (where it works better long-term) and placing a donor graft in the pulmonary position. The advantage is that the child’s own valve can grow with them and does not require blood-thinning medication. The disadvantage is that it is a more complex two-valve operation. It is favoured by many surgeons for children and young adults, as it avoids the need for lifelong anticoagulation and allows the valve to grow.
In most children, mild AS is stable over many years. However, AS in children tends to progress more than in adults — partly because the valve continues to change as the child grows. This is why regular follow-up is essential even when your child has no symptoms. Subvalvar AS (fibromuscular ring below the valve) is particularly prone to progression and is often intervened upon earlier.
Key Takeaways
- Aortic stenosis is a narrowing of the valve between the heart and the body — accounting for 3–6% of all CHD.
- A bicuspid aortic valve is the most common underlying cause in children.
- Severity ranges from mild (observation) to critical neonatal AS (emergency).
- The dangerous triad of severe AS: chest pain, syncope, and exertional breathlessness.
- Treatment options include balloon valvuloplasty, surgical valvotomy, and eventually valve replacement (Ross procedure preferred in children).
- All children with aortic stenosis need lifelong cardiological follow-up.
Sources
Allen HD et al. Moss and Adams’ Heart Disease in Infants, Children, and Adolescents, 10th Ed. Wolters Kluwer, 2021.
Rudolph AM. Congenital Diseases of the Heart, 3rd Ed. Wiley-Blackwell, 2009.
Educational purposes only. Not a substitute for professional medical advice.
