---
title: Pulmonary valve stenosis
description: What congenital pulmonary valve stenosis is, why the wall of the right ventricle thickens, how the defect shows itself and is found, what approaches to treatment clinical guidelines describe, and when urgent help is needed.
type: disease
aliases:
  - pulmonary stenosis
  - pulmonic stenosis
  - valvular pulmonary stenosis
sources:
  - tier: guideline
    org: minzdrav-rf
    title: Врожденный стеноз клапана легочной артерии
    year: 2025
    url: https://cr.minzdrav.gov.ru/view-cr/731_2
  - tier: guideline
    org: esc
    title: 2020 ESC Guidelines for the management of adult congenital heart disease
    year: 2020
    doi: 10.1093/eurheartj/ehaa554
    url: https://doi.org/10.1093/eurheartj/ehaa554
  - tier: reference
    org: msd-manuals
    title: Pulmonary Stenosis
    year: 2025
    url: https://www.msdmanuals.com/professional/cardiovascular-disorders/valvular-disorders/pulmonary-stenosis
sources_checked: 2026-10-13
review: null
---

Pulmonary valve stenosis is a congenital heart defect in which there is an obstruction to blood flow from the <Structure id="right-ventricle">right ventricle</Structure> into the <Structure id="pulmonary-trunk">pulmonary artery</Structure> at the level of the <Structure id="pulmonary-valve">pulmonary valve</Structure>: the valve leaflets do not open fully.<Cite n={[1, 3]} /> It is one of the most common congenital heart defects: according to the Russian Ministry of Health guideline, it accounts for 7 to 12% of all congenital heart defects, and it is usually the person's only defect.<Cite n={[1, 2]} />

The path of blood from the right ventricle to the lungs can also be narrowed at other levels — below the valve or above it, in the pulmonary artery itself; this article is about narrowing at the level of the valve.<Cite n={2} /> The Russian guideline on this defect is written for children, and the 2020 European Society of Cardiology (ESC) guideline for adults.<Cite n={[1, 2]} />

<Diagram name="pulmonary-valve-stenosis">
  <p slot="normal">
    Normally, when the right ventricle contracts, the leaflets of the pulmonary valve open fully and
    blood flows freely from the right ventricle into the pulmonary artery.<Cite n={[1, 3]} />
  </p>
  <p slot="disease">
    In typical valvular stenosis the leaflets are fused and form a dome with a narrow opening in the
    centre.<Cite n={[1, 2]} /> Blood passes through this opening as a narrow, fast jet; its speed,
    measured by Doppler ultrasound, is used to judge how severe the stenosis is.<Cite n={[2, 3]} />
    Beyond the valve the flow is turbulent.<Cite n={1} /> The right ventricle has to generate a
    higher pressure, so its wall thickens and its cavity becomes smaller.<Cite n={1} /> The pulmonary
    trunk beyond the valve is not uncommonly dilated.<Cite n={[1, 2]} /> Less often the valve is dysplastic:
    the leaflets are thickened and poorly mobile, and the trunk is usually not dilated; the diagram
    shows the typical form.<Cite n={[1, 2]} />
  </p>
</Diagram>

## Why it happens

<Patient>

It is a developmental defect: the pulmonary valve forms abnormally before birth.<Cite n={1} /> It is most often found in children.<Cite n={3} /> Sometimes the stenosis is part of a genetic condition, Noonan syndrome, and in adults stenosis is occasionally acquired, in carcinoid syndrome.<Cite n={[2, 3]} /> Pulmonary valve stenosis can also be part of a complex defect, [tetralogy of Fallot](../tetralogy-of-fallot/).<Cite n={3} />

To push blood through the narrow valve, the right ventricle has to contract harder: the pressure inside it rises and its muscular wall gradually thickens.<Cite n={1} /> The pressure in the pulmonary artery itself usually stays normal.<Cite n={1} /> This is what sets the defect apart from [pulmonary hypertension](../pulmonary-hypertension/), in which the pressure in the pulmonary artery is raised.<Cite n={1} />

</Patient>

<Student>

According to the Russian guideline, isolated valvular stenosis results from fusion of the leaflets without abnormal development of the right ventricular outflow tract (RVOT); more often the leaflets are fused around the whole circumference and form a membrane with an opening.<Cite n={1} /> The ESC describes a typical dome-shaped pulmonary valve with a narrow central opening but a preserved mobile valve base; a dysplastic valve, with poorly mobile cusps and myxomatous thickening, is less common (15–20%) and frequently part of Noonan syndrome.<Cite n={2} />

The main compensatory mechanism is a rise in right ventricular (RV) pressure; the key haemodynamic feature of the defect is the systolic pressure gradient between the RV and the pulmonary artery (PA).<Cite n={1} /> RV hypertrophy increases its stiffness and reduces its cavity, diastolic pressure rises and with it right atrial pressure, which leads to right atrial dilatation and hypertrophy; the foramen ovale may be stretched open, shunting part of the blood into the left heart.<Cite n={1} />

</Student>

<HeartModel highlight={['pulmonary-valve', 'right-ventricle', 'pulmonary-trunk']} />

## Symptoms

<Patient>

Pulmonary valve stenosis often causes no complaints for a long time.<Cite n={[1, 3]} /> Mild stenosis in adults who have not had an operation usually does not get worse, and in children it may lessen and even disappear.<Cite n={[2, 3]} />

When symptoms do appear, the main complaint is breathlessness on exertion, and with severe stenosis even at rest.<Cite n={1} /> Poor exercise tolerance, fainting and chest pain can occur.<Cite n={[2, 3]} /> In a baby, poor weight gain may point to the defect, and school-age children often complain of pain in the heart area.<Cite n={1} />

A bluish colour of the skin (cyanosis) does not always occur with this defect: it can appear if the foramen ovale stays open or if there are other heart defects.<Cite n={1} />

</Patient>

<Student>

The course depends above all on the degree of narrowing.<Cite n={1} /> According to the ESC, patients with mild-to-moderate valvular stenosis are usually asymptomatic; moderate stenosis can progress at the valvular level (calcification) or below the valve because of reactive myocardial hypertrophy; patients with severe stenosis may present with dyspnoea and reduced exercise capacity and have a worse prognosis.<Cite n={2} />

Examination may show distended, pulsating jugular veins, an RV heave, and a systolic thrill to the left of the sternum in the second intercostal space, over the PA.<Cite n={[1, 3]} />

</Student>

## How it is diagnosed

<Patient>

When listening to the heart, the doctor hears a harsh murmur while the heart contracts — to the left of the breastbone, in the second space between the ribs.<Cite n={[1, 2, 3]} />

The main test is a [heart ultrasound (echocardiography)](../../diagnostic/echocardiography/) with Doppler: it confirms the diagnosis, shows at what level the narrowing is and makes it possible to assess how severe it is.<Cite n={[1, 2, 3]} /> An [ECG](../../diagnostic/ecg/) may be normal with mild stenosis, and with more severe stenosis it shows signs of a thickened right ventricular wall.<Cite n={[1, 3]} /> A chest X-ray often shows a dilated pulmonary trunk.<Cite n={1} /> CT or MRI of the heart is done when the ultrasound findings need to be clarified or treatment needs to be planned.<Cite n={[1, 2]} />

</Patient>

<Student>

The ESC grades severity by the peak Doppler gradient, in the presence of normal RV function and normal transvalvular flow: mild obstruction is below 36 mm Hg, moderate 36–64 mm Hg and severe above 64 mm Hg.<Cite n={2} /> MSD gives the same cut-offs with the matching peak velocities: below 3, 3–4 and above 4 m/s.<Cite n={3} /> The Russian guideline gives the paediatric classification by E. W. Nugent, which has four groups with different cut-offs for the systolic gradient between the RV and the PA: group 1, below 25 mm Hg; group 2, 25–49 mm Hg; group 3, 50–79 mm Hg; group 4, above 80 mm Hg. The guideline names them "moderate", "of medium severity", "marked" and "severe" stenosis, so its "moderate" is the mildest group and is not the ESC's moderate.<Cite n={1} /> Gradients only reflect severity when RV systolic function is good, and with stenoses in series the Bernoulli equation overestimates the gradient.<Cite n={2} />

On auscultation the second heart sound is widely split; as the stenosis becomes more severe, its pulmonary component becomes softer.<Cite n={[2, 3]} /> With stenosis of medium severity and marked stenosis (Nugent groups 2 and 3) the ECG shows RV hypertrophy and right axis deviation, and with extreme RV overload ST depression and T-wave inversion in the right precordial leads; right bundle branch block may be present.<Cite n={[1, 3]} /> Echocardiography distinguishes classic valvular stenosis from dysplasia: in dysplasia the leaflets are thickened and immobile, the annulus is hypoplastic, there is subvalvular narrowing and no post-stenotic dilatation of the PA.<Cite n={1} /> The Russian guideline recommends cardiac catheterisation for patients in whom a transcatheter intervention on the valve is planned at the same time.<Cite n={1} />

</Student>

## How it is treated

<Patient>

Most people without symptoms do not need medicines.<Cite n={1} /> The outlook is usually good: with minor stenosis it is good even without an operation, and when an intervention is needed, it improves the outlook.<Cite n={[1, 3]} /> An intervention is considered if there are symptoms or the stenosis is severe; whether it is needed and when is decided by the doctor based on the test results.<Cite n={[2, 3]} />

The main treatment is balloon valvuloplasty: a thin catheter with a balloon is passed through a blood vessel to the valve, and the balloon is inflated to widen the narrowed valve and reduce the pressure difference between the right ventricle and the pulmonary artery.<Cite n={[1, 2, 3]} /> If a balloon is not suitable — for example, with a dysplastic valve, a narrow valve ring or narrowing below the valve — open-heart surgery is done: the valve is repaired or replaced.<Cite n={[1, 2, 3]} /> These interventions are carried out in centres that specialise in congenital heart disease.<Cite n={2} /> With heart failure, the doctor may prescribe medicines for a short time to prepare the patient for the intervention.<Cite n={1} />

After treatment some narrowing may remain, or the valve may start to leak, so that part of the blood returns to the right ventricle; sometimes another procedure is needed later.<Cite n={[1, 2]} /> That is why, according to the ESC guideline, follow-up with a cardiologist and regular heart ultrasound is needed for life.<Cite n={2} /> With timely treatment, life expectancy and physical capacity can be fully restored.<Cite n={1} />

With mild stenosis there are no restrictions on sport; with more severe stenosis the doctor decides what level of activity is safe.<Cite n={[1, 2]} /> According to the ESC, pregnancy in adults is usually well tolerated unless the stenosis is extremely severe or there is marked right ventricular failure.<Cite n={2} />

</Patient>

<Student>

The Russian guideline recommends transluminal balloon valvuloplasty as the first step, unless contraindicated, to reduce the gradient between the RV and the PA; contraindications are hypoplasia of the pulmonary annulus (Z-score below −3), a unicuspid valve and subvalvular stenosis.<Cite n={1} /> According to the ESC, in valvular stenosis balloon valvuloplasty is the intervention of choice if anatomically suitable; surgery is recommended for sub-infundibular or infundibular stenosis, a hypoplastic annulus, dysplastic valves and associated lesions that need a surgical approach, such as severe pulmonary or tricuspid regurgitation.<Cite n={2} /> The Russian guideline and the ESC set the gradient-based indications for intervention differently; the decision is made by the doctor.<Cite n={[1, 2]} />

In critical stenosis in newborns, balloon valvuloplasty is performed under a continuous intravenous infusion of prostaglandins.<Cite n={1} /> In heart failure, the Russian guideline allows short-term treatment with diuretics, beta-blockers and ACE inhibitors before surgical correction.<Cite n={1} />

After an intervention there may be a residual gradient, recurrent subvalvular obstruction and progressive pulmonary regurgitation; regurgitation may need reintervention later in life.<Cite n={[1, 2]} /> See the article on [pulmonary regurgitation](../pulmonary-regurgitation/) for more. The ESC recommends lifelong follow-up with regular echocardiography.<Cite n={2} />

</Student>

## When to call an ambulance

Very severe (critical) stenosis in a newborn can show itself as cyanosis and heart failure; such a baby can be extremely ill and need an urgent intervention.<Cite n={1} /> If a newborn's lips and skin turn blue, call your local emergency number (112 in the EU, 911 in the US and Canada, 999 in the UK) straight away.

As with any heart condition, call an ambulance for fainting, chest pain or severe breathlessness: this is the site's general safety rule, repeated at the bottom of every page.

<Quiz />