Valvular Pulmonic Stenosis
Definition
An obstruction of blood flow from the right ventricle to the main pulmonary artery during systole
Etiology
- Congenital (most commonly due to fusion of the valve cusps)
- Carcinoid
- Rheumatic (uncommon)
Signs and Symptoms
- Dyspnea on exertion
- Jugular venous distention
Cardiac Auscultation
- Harsh systolic ejection murmur heard best in the second left intercostals space
- An early systolic ejection sound may be present and may be accentuated with expiration
- A thrill may be present
- P2 is present and may be faint
Electrocardiogram
- Right ventricular hypertrophy
- Right atrial enlargement
Chest X-ray
- Cardiomegaly
- Post-stenotic dilatation of the main pulmonary artery
Treatment
- Valvuloplasty or valve replacement
M-Mode
- An increased "a" dip (≥ 8 mm) of the pulmonic valve
- Right ventricular hypertrophy (wall thickness > 9 mm)
- Increased right ventricular ejection time
2-D
- Thickened pulmonic valve leaflets
- Systolic "doming" of the pulmonary valve leaflets
- Right ventricular hypertrophy (possible asymmetric septal hypertrophy)
- Right atrial enlargement
- Post-stenotic dilatation of the main pulmonary artery
PW Doppler
- Sample the entire right ventricular outflow tract because subinfundibular, infundibular, main, and pulmonary branch stenosis are possible, either as a part of valvular pulmonic stenosis or as separate entities
- Turbulent flow
- Increased velocity across the pulmonic valve > 1 m/sec in valvular pulmonic stenosis
CW Doppler
- Determine the maximum instantaneous pressure gradient
- Determine the mean transvalvular pressure gradient
- Determine the pulmonic valve area utilizing the continuity equation
- Determine the presence and severity of pulmonary regurgitation
- Mild PS, peak gradient <50 mm Hg
- Moderate 50-75 mm Hg
- Severe >75 mm Hg
Color Flow Doppler
- May aid in determining the direction of the stenotic jet thus aiding in the CW Doppler interrogation of the stenotic valve