Following trauma, the new collagen formed during healing may be weaker and predispose to prolapse.
Prolapse was seen in three, while two showed increased echogenicity of the leaflets.
There was no systolic anterior motion of the mitral valve, but mild prolapse of an aortic leaflet was seen.
The leaflets of the valve were redundant with prolapse (myxomatous-like) in ten patients (17.8%).
Implicated mechanisms for spontaneous closure are again muscular overgrowth, but include prolapse of the leaflets of the aortic valve into the defect.
Annular dilatation or abnormalities of leaflets and tension apparatus, notably prolapse, are the common cause of incompetence, and again can be congenital or acquired.
Three patients had prolapsed leaflets and elongated chords.
The degree of prolapse muscles associated with hypoplasia of the leaflet may be overestimated when there is retraction of tissue close to the muscle.
