The invention relates to an implant for improving coaptation of an atrioventricular valve in a heart, the atrioventricular valve having a native first leaflet, a native second leaflet and optionally an annulus adjacent a wall of an atrium of the heart, the implant comprising a support structure configured to be arranged on and fixed to the annulus or to at least one of the first and second native leaflets, the implant further comprising retention means fixed to the support structure so as to prevent prolapse of the at least one native leaflet, whereby the support structure comprises a resting element that is configured to rest against the wall of the atrium adjacent the valve.
