Findings suspicious for prosthetic pulmonary valve stenosis
Cusp or leaflet thickening or immobility
Narrowing of forward color map
Peak velocity through the prosthesis >3 m/s or >2 m/s through a homograft*
Increase in peak velocity on serial studies**
Impaired RV function or elevated RV systolic pressure

*Suspicious but not diagnostic of stenosis.
**More reliable parameter.