| Types | Leaflet motion | Mechanism |
| Type 1 | Normal motion | Annular dilation, clefts, leaflet perforation |
| Type II | Excessive motion | Prolapse, flail chords, ruptured papillary muscle |
| Type III | Restricted motion |
|
| Type IIIa | Restriction during diastole and systole | Commissural fusion due to rheumatic heart disease |
| Type IIIb | Restriction during systole only | Chordal tethering, papillary musle displacement |