Pulmonary Valve Stenosis

Key Features

Essentials of Diagnosis

• High-pitched systolic ejection murmur maximal in the second left interspace with radiation to the left shoulder

• P₂ delayed and soft or absent

• Pulmonary ejection click often present and decreases with inspiration—the only right heart sound that decreases with inspiration; all other right heart sounds increase

• Echocardiography/Doppler is diagnostic

• Patients with peak pulmonic valve gradient > 64 mm Hg or a mean of 35 mm Hg by echocardiography/Doppler should undergo intervention regardless of symptoms; otherwise, percutaneous or surgical intervention may be indicated for symptoms or evidence of right ventricular (RV) dysfunction

General Considerations

• Often congenital and associated with other cardiac lesions

• In valvular pulmonic stenosis, pulmonary blood flow preferentially goes to the left lung

• Most patients with valvular pulmonic stenosis have a domed valve, although some patients have a dysplastic valve

• Peripheral pulmonic stenosis

  • Can accompany valvular pulmonic stenosis

  • May be part of a variety of clinical syndromes, including the congenital rubella syndrome

• Noncongenital postoperative pulmonic valvular or main pulmonary artery (PA) stenosis

  • May be seen in patients who have had the Ross procedure for aortic valve disease

  • Occurs due to an immune response in the homograft

• RV outflow obstructions can also occur when there is

  • A conduit from the RV to the pulmonary artery that becomes stenotic from degenerative changes over time

  • Degeneration of a bioprosthetic replacement pulmonary valve

Clinical Findings

• Mild cases of pulmonic stenosis are asymptomatic

• Moderate to severe pulmonic stenosis may cause

  • Dyspnea on exertion

  • Syncope

  • Chest pain

  • RV failure

• In mild to moderate pulmonic stenosis

  • A loud ejection click can be heard to precede the murmur

  • This sound decreases with inspiration as the increased RV filling from inspiration prematurely opens the valve during atrial systole when inspiratory increased blood flow to the right heart occurs

• In severe pulmonic stenosis

  • The second sound is obscured by the murmur

  • Pulmonary component of S₂ may be diminished, delayed, or absent

  • A right-sided S₄ and a prominent a wave in the venous pulse are present when there is RV diastolic dysfunction or a c-v wave may be observed in the jugular venous pressure if tricuspid regurgitation is present

• Stenosis of the pulmonary valve or RV infundibulum increases the resistance to RV outflow, raises the RV pressure, and limits pulmonary blood flow

Diagnosis

Imaging

• Radiography

  • Heart size may be normal

  • A prominent RV and RA or gross cardiac enlargement may be present, depending on the severity

• Echocardiography/Doppler

  • Diagnostic

  • Can provide evidence for a doming valve versus a dysplastic valve

  • Can estimate the gradient across the valve

  • Peak gradients

    • Mild pulmonic stenosis: < 36 mm Hg

    • Moderate pulmonic stenosis: 36–64 mm Hg

    • Severe pulmonic stenosis: > 64 mm Hg (or mean ...