Definition
“Coaptation reserve” defined by the actual contact area of the
leaflets is less well established, but is still crucial for the
intraoperative guidance of MV repair. The leaflet coaptation failure of
IMR is due to annular dilatation, leaflet tethering caused by papillary
muscle displacement, or both[73].
“Mitral valve reserve” refers to
the degree of apposition of the MV leaflets that allows the apparatus to
maintain further remodeling without overt systolic
incompetence[7,8]. Restrictive annuloplasty is
performed under these circumstances to reduce annular area, provide a
greater zone of coaptation between the MV leaflets, and consequently
reduce the severity of MR[9]. However, in IMR, the
remodeling of the MV apparatus can be heterogeneous with varying degrees
of apposition/reserve along the coaptation
line[10,11].