Pulmonic Stenosis (Pulmonary Stenosis)

Updated: Dec 14, 2020
  • Author: Priya Pillutla, MD; Chief Editor: Richard A Lange, MD, MBA  more...
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Pulmonic stenosis (pulmonary stenosis) (PS) refers to a dynamic or fixed anatomic obstruction to flow from the right ventricle (RV) to the pulmonary arterial vasculature, which leads to RV pressure overload that in turn causes increased contractility and dilation and results in increased wall stress and compensatory RV hypertrophy. [1] Although most commonly diagnosed and treated in the pediatric population, individuals with complex congenital heart disease are surviving into adulthood and require ongoing assessment and cardiovascular care. [2]  These adults often also have severe heart structural diseases. [1, 3]  Some patients with severe, isolated PS may be diagnosed for the first time as adults.



Pulmonic stenosis (pulmonary stenosis) (PS) can be due to isolated valvular (90%), subvalvular, or peripheral (supravalvular) obstruction, or it may be found in association with more complicated congenital heart disorders. [1, 3] The characteristics of the various types of PS are described in this section. [4]

Valvular pulmonic stenosis

Isolated valvular PS comprises approximately 10% of all congenital heart disease. Typically, the valve commissures are partially fused and the three leaflets are thin and pliant, resulting in a conical or dome-shaped structure with a narrowed central orifice. Poststenotic pulmonary artery dilatation may occur owing to "jet-effect" hemodynamics or an underlying connective tissue disorder.

Alternatively, approximately 10-15% of individuals with valvular PS have dysplastic pulmonic valves. These valves have irregularly shaped, thickened leaflets with little if any commissural fusion and they exhibit variably reduced mobility. The leaflets are composed of myxomatous tissue, which may extend to the vessel wall. The valve annulus is usually small and the supravalvular area of the pulmonary trunk is usually hypoplastic. Poststenotic dilatation of the pulmonary artery is uncommon. Approximately two-thirds of patients with Noonan syndrome have PS due to dysplastic valves.

Bicuspid morphology, while rare in individuals with isolated valvular PS, is more common in those with tetralogy of Fallot.

Subvalvular pulmonic stenosis

Subvalvular PS may be due to an underlying disorder or a secondary phenomenon in the setting of valvular PS. The former is characterized by fibromuscular narrowing of the right ventricular outflow tract and is possibly a variant of double chambered-right ventricle. In contrast, secondary outflow tract narrowing may occur due to primary valvular PS. This typically resolves after correction of valvular stenosis. Subvalvular PS is one of the defining characteristics of tetralogy of Fallot.

Peripheral pulmonary stenosis

Peripheral pulmonary stenosis (PPS) can cause obstruction along the pulmonary artery anywhere from the main pulmonary artery to distal pulmonary artery branches. PPS may occur at a single level, but multiple sites of obstruction are more common. PPS may be associated with other congenital heart anomalies such as valvular PS, atrial septal defect (ASD), VSD or patent ductus arteriosus (PDA). Up to 20% of patients with tetralogy of Fallot have associated PPS.

Functional or physiologic PPS is a common cause of a systolic murmur in infants. It occurs in both premature and full-term infants; with time, the pulmonary artery grows and the murmur usually disappears within a few months.

Poststenotic dilatation occurs with discrete segmental stenosis but is absent if the stenotic segment is long or if the pulmonary artery is diffusely hypoplastic.

PPS is associated with various inherited and acquired conditions including rubella and the Alagille, cutaneous laxa, Noonan, Ehlers-Danlos, and Williams syndromes.



Causes of acquired pulmonic stenosis (pulmonary stenosis) (PS) include the following:

  • PS is a rare manifestation of rheumatic heart disease, and it follows involvement of the mitral and aortic valves.

  • Carcinoid may result in development of myxomatous plaques in the RV outflow tract, with distortion and constriction of the pulmonic ring, as well as fusion or destruction of pulmonary valve leaflets, resulting in both stenosis and regurgitation.

  • Rarely, cardiac tumors can grow on or into the RV outflow tract and cause flow obstruction.

  • Sinus of Valsalva aneurysms and aortic graft aneurysms are extracardiac entities that can cause PS by external compression.

See also Pathophysiology.



United States data

Pulmonic stenosis (pulmonary stenosis) (PS) is a common form of congenital heart disease that occasionally is diagnosed for the first time in adulthood. Isolated valvular PS comprises approximately 10% of all congenital heart disease in the United States. About 2% of familial occurrences are without a genetic cause. [3]

Sex-related demongraphics

A slight female predominance exists. [3]



Except for critically severe stenosis in neonates, survival is the rule for individuals with congenital pulmonic stenosis (pulmonary stenosis) (PS). [5]  The long-term course of individuals with mild PS is indistinguishable from that of the unaffected population. Mild PS does not tend to progress in severity; rather, pulmonic valve orifice size usually increases with body growth. Severe PS may result in outflow obstruction that progresses over a period of years despite body growth (60% of patients require intervention within 10 y of diagnosis). With appropriate intervention, those with moderate and severe PS have an excellent prognosis. When PS is corrected during childhood, the life expectancy of the affected individual matches that of the unaffected age- and sex-matched cohort. The more severe and protracted the course of PS, the less optimal the outcome of intervention, including death due to RV failure in the most severe cases.

Balloon valvuloplasty is preferred, provided the valve is compliant and mobile. Those with severe valvular fibrocalcific thickening are more likely to require a surgical approach. Following balloon valvuloplasty, there can be residual PS or pulmonary regurgitation (usually mild or moderate); both may be followed by serial echocardiography. The recurrence rate of PS in patients who are treated surgically is approximately 4%. Long-term results of balloon valvuloplasty are comparable to the results of surgical repair, with the rate of recurrence of severe PS less than 5%. [6]  Following surgical treatment for isolated pulmonary valve stenosis, a high rate of reinterventions has been reported (53% at a median follow-up of 34 years). Thus, close follow-up in all patients who have undergone intervention is needed. [7]

Adult patients are more likely to present with subvalvular hypertrophic pulmonic stenosis or valvular fibrocalcific thickening. Secondary subvalvular hypertrophic stenosis regresses following correction of the primary valvular abnormality, and residual dilatation of the pulmonary trunk is typically not significant clinically, even when marked. Recognizing subvalvular hypertrophy is important, since it may lead to dynamic outflow obstruction during the acute phase following correction of valvular stenosis.


Except for critical stenosis in neonates, survival is the rule in congenital PS.

The long-term course of patients with mild PS is indistinguishable from that of the unaffected population. Mild PS tends to be stable in severity as the pulmonic valve orifice size usually increases with body growth. However, untreated severe PS may result in outflow obstruction that progresses over a period of years; 60% of patients with severe PS require intervention within 10 years of diagnosis.