ConditionHeart & circulation
Pulmonary Stenosis (Pulmonary Valve Stenosis)
Pulmonary stenosis is a narrowing of the pulmonary valve, which lets blood flow from the right side of the heart to the lungs. It is almost always present from birth and is one of the more common congenital heart defects. Mild stenosis causes no symptoms and needs no treatment. Moderate or severe narrowing makes the right ventricle work harder and can cause breathlessness, tiredness or, in newborns, blue skin. Balloon valvuloplasty through a catheter is the usual treatment and works very well.
Also called: Pulmonic stenosis, pulmonary valve stenosis, right ventricular outflow tract obstruction
At a glance
- What it is
- A narrowed pulmonary valve, restricting blood flow to the lungs.
- Cause
- Usually congenital. Associated with Noonan syndrome, Williams syndrome and other heart defects.
- Severity
- Graded by the pressure gradient across the valve on echocardiogram.
- Symptoms
- None in mild cases. Breathlessness, tiredness, chest pain or fainting when severe. Cyanosis in critical newborn cases.
- Treatment
- Balloon valvuloplasty for moderate to severe stenosis. Surgery in some cases.
- Outlook
- Excellent for most people.
When to get help
Call 911 or go to the ER
- A newborn with blue or gray lips or skin, fast breathing or poor feeding
- Fainting during exercise, or chest pain with exercise
See a doctor within a day or two
- New breathlessness, tiredness or leg swelling in someone known to have pulmonary stenosis
- Fever lasting several days in someone who has had valve surgery or a valve replacement
Book a routine appointment
- A heart murmur found at a checkup
- Scheduled follow-up echocardiograms, including during pregnancy planning
How pulmonary stenosis affects the heart
The pulmonary valve has three thin flaps (leaflets) that open as the right ventricle pumps blood into the pulmonary artery. In pulmonary stenosis, the leaflets are thickened or fused, or the valve ring is small. The right ventricle has to pump harder, raising its pressure and thickening its wall. Severe, long-standing stenosis can lead to right heart failure.
Narrowing can also occur just below the valve (subvalvular) or above it in the pulmonary arteries (supravalvular or branch stenosis).
Causes
- congenital in nearly all cases, about 8 to 10% of congenital heart defects
- associated syndromes: Noonan syndrome, Williams syndrome, Alagille syndrome, congenital rubella
- part of complex defects, such as tetralogy of Fallot
- rarely acquired, from rheumatic fever or carcinoid syndrome
Symptoms
Mild stenosis
No symptoms. A heart murmur is often found during a routine checkup.
Moderate to severe stenosis
- shortness of breath with exertion
- tiredness and reduced exercise capacity
- chest pain
- fainting or dizziness with exercise
- swelling of the legs or abdomen if right heart failure develops
Critical stenosis in newborns
A very narrow valve in a newborn causes cyanosis (blue color), fast breathing and poor feeding within days. It is an emergency that requires urgent treatment and sometimes a medicine (prostaglandin) to keep a fetal blood vessel open.
Diagnosis
- examination: a characteristic murmur and sometimes a click
- echocardiogram: the main test. It shows the valve and measures the pressure gradient across it
- ECG: may show right ventricular thickening
- chest X-ray: may show an enlarged pulmonary artery
- cardiac MRI or CT for complex anatomy
- cardiac catheterization, usually as part of treatment
Severity
| Severity | Peak gradient (mm Hg) | Typical approach |
|---|---|---|
| Mild | Under 36 | Observation |
| Moderate | 36 to 64 | Intervention if symptoms or other findings |
| Severe | Over 64 | Intervention usually recommended |
Treatment
- Balloon valvuloplasty: a catheter with a balloon is passed from a vein in the groin to the valve and inflated to open it. It is the treatment of choice for typical valve stenosis, with high success rates and quick recovery
- Surgical valvotomy or valve replacement: for dysplastic (thickened) valves, which are common in Noonan syndrome, or narrowing above or below the valve
- Transcatheter pulmonary valve replacement: for leaky or failing valves after earlier repairs
- Monitoring: lifelong cardiology follow-up, because the valve may leak (pulmonary regurgitation) after treatment
Complications
- right heart failure in untreated severe stenosis
- arrhythmias
- pulmonary regurgitation after treatment
- endocarditis, uncommon
Living with pulmonary stenosis
Most people with mild stenosis or successful treatment lead normal lives, including sports and pregnancy. People with moderate or severe stenosis should discuss exercise and pregnancy plans with their cardiologist. Antibiotics before dental work are recommended only for those with prosthetic valves or certain repairs.
Frequently asked questions
What is pulmonary stenosis?
It is a narrowing of the pulmonary valve, which controls blood flow from the right side of the heart to the lungs. It is usually present from birth and ranges from mild, needing no treatment, to severe, needing a procedure to open the valve.
What are the symptoms of pulmonary stenosis?
Mild stenosis usually causes no symptoms. More severe narrowing can cause breathlessness, tiredness, chest pain and fainting with exercise. Newborns with critical stenosis may have blue skin, fast breathing and feeding problems.
Is pulmonary stenosis serious?
Mild pulmonary stenosis is not serious and often never progresses. Severe stenosis strains the heart and needs treatment, but balloon valvuloplasty is highly effective, and most people have an excellent long-term outlook.
How is pulmonary stenosis treated?
The standard treatment is balloon valvuloplasty, in which a balloon on a catheter is inflated to open the valve. Surgery is needed for some valve types or narrowing above or below the valve. Mild cases only need regular checkups.
Can pulmonary stenosis get worse?
Mild stenosis in older children and adults usually stays stable. In infants, it can progress during the first year of life, so regular echocardiograms are recommended.
Sources
This guide was written from current patient and clinical guidance, including:
- American Heart Association: Pulmonary Valve Stenosis
- ACC/AHA: 2018 Guideline for the Management of Adults With Congenital Heart Disease
- MedlinePlus: Pulmonary valve stenosis
- Cincinnati Children's Hospital: Pulmonary Valve Stenosis
- NHS: Congenital heart disease