Name three ways to differentiate a vegetation from the other possible causes of a mass on a valve leaflet.

1. The clinical picture: clinical signs of septic emboli may be the best clue.
2. Movement: unrestricted movement of the leaflets is often an important clue because in rheumatic valvular disease, leaflet movement is restricted.
3. Focal versus diffuse: myxomatous degeneration involves the entire leaflet and is associated with leaflet redundancy, whereas vegetations are discrete.