Pulmonic valve stenosis occurs when the pulmonic valve is not able to open normally in systole. This results in right ventricular pressure overload, right ventricular hypertrophy and eventual right ventricular heart failure.
The vast majority of cases of pulmonic valve stenosis are congenital.
The symptoms include those of right heart failure predominantly dyspnea on exertion.Lower extremity dependant edema can occur and when the legs are elevated at night, the fluid redistributes centrally causing pulmonary edema resulting in orthopnea (dyspnea while laying flat) or paroxysmal nocturnal dyspnea (PND). Hepatic congestion can occur causing right upper quadrant abdominal pain.
Findings of right heart failure can be seen upon physical examination including elevated jugular venous pressure, hepatojugular reflux and lower extremity edema.
The murmur of pulmonic stenosis is very similar to that of aortic stenosis. It is a midsystolic high-pitched crescendo-decrescendo murmur heard best at the pulmonic listening post and radiating slightly toward the neck, however the murmur of pulmonic stenosis does not radiate as widely as that of aortic stenosis. The murmur of pulmonic stenosis peaks early if the disease is mild and peaks later as the disease progresses.
Also, the murmur of pulmonic stenosis demonstrates increased intensity during inspiration due to the increased venous return to the right heart resulting in greater flow across the pulmonic valve.
While the murmur of aortic stenosis extends up to the A2 component of the S2 heart sound, the murmur of pulmonic stenosis extends through the A2 sound up to the P2 component of the S2 heart sound.
Severe PS results in decreased mobility of the pulmonic valve leaflets and thus a softer P2 sound. Also, as the pulmonic stenosis worsens, the closure of the pulmonic valve is delayed, since more time is required to eject blood through the stenotic valve, resulting in a widely split S2 heart sound that still exhibits inspiratory delay. Note that the murmur of an atrial septal defect is also midsystolic, however it has a fixed split S2.
Diagnosis is made on echocardiography by visualization of the restricted pulmonic valve leaflets and measuring of the peak gradient across the valve with continuous wave Doppler.
Treatment includes pulmonic valvuloplasty.