Exposure of the papillary muscles
The first step is to achieve a good exposure of the papillary muscles that is of pivotal importance before approaching the implant of the artificial chords. Erlebach et al.16 proposed an elegant way to push both MV leaflet aside to, using a standard valve prosthesis sizer so to have a clear view of the papillary muscles. They usually use a 29-mm valve sizer, advising to use smaller ones in case of a smaller mitral ring. Other surgeons17 introduced a novel leaflets retractor manufactured from nickel–titanium alloy that can be easily rolled to a cylindrical form with a diameter of 15mm and grasped with a long needle holder. Once it is introduced into the MV annulus, releasing the needle holder, the retractor opens spontaneously, so that MV leaflets are pushed to the sides.