Table 4.19 - Characteristics in pulmonary stenosis.

Obstruction to RV outflow increases afterload of RV; to eject normal flow the RV must increase systolic pressure (P = F x R); resultant increase in wall stress leads to cardiomegaly. Chamber volume remains normal, if compensated, since flow is not increased.
May be subvalvular, valvular, or supravalvular.
Beyond the stenosis, pulmonary resistance is normal, so large pressure gradient is present across the obstruction.
No shunt occurs unless there is a defect in septae; thus no cyanosis.
No symptoms occur unless RV cannot compensate to provide normal flow.
RV enlargement is seen by ECG, RV heave felt.
Loud, harsh systolic ejection murmur is heard; if valve is compliant an early systolic click occurs.

valve area =	stroke flow -------------------------------------------- 0.5 x mean pressure gradient