Pulmonary Stenosis – Types, Symptoms, and Treatment
- Dr Amitoz Baidwan
- 2 days ago
- 4 min read
Pulmonary stenosis is a condition in which blood flow from the right ventricle to the lungs becomes restricted because the pathway leading to the lungs is narrowed. In most individuals, this narrowing develops before birth, which is why it is classified under congenital heart disease.
Pulmonary stenosis affects how efficiently the heart pumps blood to the lungs and can range from mild to severe. The level of narrowing determines how much extra effort the right side of the heart must make and whether symptoms or medical intervention are necessary.
What You Will Learn:
How Pulmonary Stenosis Affects Blood Flow
To understand the condition clearly, look at the comparison below
Normal vs Pulmonary Stenosis Blood Flow
Normal Flow
Body → Right Atrium → Right Ventricle → Pulmonary Valve (Open) → LungsPulmonary Stenosis
Body → Right Atrium → Right Ventricle → Pulmonary Valve (Narrowed) → Lungs ↑ Increased Pressure in Right VentricleWhen the valve or pathway is narrowed, the right ventricle must pump harder. Over time, this may lead to thickening of the heart muscle and symptoms depending on severity.
Pulmonary Stenosis Causes
Understanding pulmonary stenosis causes is important because management depends on the underlying reason.
1. Congenital Causes (Most Common)
Abnormal formation of the pulmonary valve during fetal development
Thickened or fused valve leaflets
Narrowed pulmonary artery from birth
This is why pulmonary stenosis is categorized under congenital heart disease.
2. Genetic Syndromes
Some children with genetic conditions may develop pulmonary valve abnormalities.
3. Acquired Causes (Rare)
In adults, pulmonary stenosis may rarely develop due to:
Rheumatic heart disease
Carcinoid syndrome
Post-surgical scarring
Tumors affecting the pulmonary artery
However, congenital origin remains the leading cause.
Pulmonary Stenosis Types
Pulmonary stenosis types are classified based on the location of narrowing.
Types Based on Location
Pulmonary Artery ↑ --------------------- | Supravalvular | --------------------- ↑ --------------------- | Valvular | --------------------- ↑ --------------------- | Subvalvular | --------------------- ↑ Right Ventricle1. Valvular Pulmonary Stenosis
Most common type. The narrowing is at the pulmonary valve itself.
2. Subvalvular Pulmonary Stenosis
Narrowing occurs below the valve, inside the right ventricle.
3. Supravalvular Pulmonary Stenosis
Narrowing occurs above the valve in the pulmonary artery.
Valvular type accounts for the majority of cases and responds well to catheter-based treatment.
Pulmonary Stenosis Symptoms
Pulmonary stenosis symptoms depend on severity. Mild cases may produce no symptoms and are often discovered during routine examination.
Moderate to severe cases may cause:
Shortness of breath
Fatigue during activity
Chest discomfort
Dizziness or fainting
Palpitations
In newborns with severe obstruction:
Bluish skin discoloration
Difficulty feeding
Rapid breathing
Low oxygen levels
The right ventricle works harder in severe cases, which leads to pressure buildup and symptom development.
Pulmonary Stenosis Murmur
One of the earliest clues in diagnosis is the pulmonary stenosis murmur.
A murmur is an abnormal heart sound heard through a stethoscope due to turbulent blood flow.
Characteristics of Pulmonary Stenosis Murmur
Harsh systolic ejection murmur
Heard best at the left upper chest
May radiate toward the back
Often associated with a click sound
The murmur intensity does not always equal severity, which is why echocardiography is required for accurate measurement.
In many children, pulmonary stenosis is first identified during a routine pediatric cardiologist examination when a systolic murmur is heard.
Severity Classification
Doctors use echocardiography to measure the pressure gradient across the valve.
Here is a clinical comparison:
Severity Level | Pressure Gradient | Symptoms | Typical Management |
Mild | Less than 36 mmHg | Usually none | Monitoring |
Moderate | 36–64 mmHg | Fatigue, breathlessness | Close follow-up |
Severe | Above 64 mmHg | Clear symptoms | Intervention needed |
Critical | Very high in newborns | Cyanosis | Urgent treatment |
Severity determines the need for pulmonary stenosis treatment.
Pulmonary Stenosis Treatment
Pulmonary stenosis treatment depends on severity, symptoms, and valve anatomy.
1. Monitoring
If mild and asymptomatic:
Regular cardiology check-ups
Periodic echocardiography
No immediate intervention
Many mild cases remain stable for years.
2. Balloon Valvuloplasty
This is the most common and effective treatment for valvular pulmonary stenosis.
Procedure steps:
A catheter is inserted through a vein.
A balloon is positioned across the narrowed valve.
The balloon is inflated to widen the opening.
Advantages:
Minimally invasive
Short recovery time
Highly effective in children
This is usually the first-line pulmonary stenosis treatment.
3. Surgical Repair
Surgery may be required when:
Balloon procedure is not suitable
Valve anatomy is complex
Multiple congenital defects are present
Subvalvular or supravalvular narrowing exists
Surgery may involve widening the outflow tract or repairing the valve.
4. Valve Replacement
In rare cases where the valve is severely abnormal, replacement may be necessary.
What to Expect in the Future
The prognosis for pulmonary stenosis is generally excellent when properly managed.
Mild cases often require only monitoring.
Moderate to severe cases improve significantly after intervention.
Lifelong follow-up is recommended.
Because pulmonary stenosis is commonly part of congenital heart disease, long-term care with a cardiologist experienced in CHD is important.
Why Early Diagnosis Matters
Untreated severe narrowing can cause:
Right ventricular thickening
Heart rhythm problems
Reduced exercise capacity
Long-term heart strain
Early detection through murmur evaluation and echocardiography prevents complications.
What This Means for You
Pulmonary stenosis causes are mainly congenital.Pulmonary stenosis types depend on location of narrowing.Pulmonary stenosis symptoms increase with severity.Pulmonary stenosis murmur is often the first diagnostic clue.Pulmonary stenosis treatment ranges from monitoring to balloon or surgery.
With modern medical care, most patients live healthy and active lives when diagnosed and treated appropriately.
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