Atrioventricular valve repair

A method for use with an annuloplasty ring, and an atrioventricular valve of a heart of a mammalian subject, the atrioventricular valve including a valve annulus, valve leaflets, chords, and papillary muscles, the method comprising:

• deploying a plurality of chord-manipulation arms among the chords of the atrioventricular valve;
• subsequently rotating the arms, such that the arms cause a size of the valve annulus to decrease, by the arms twisting the native atrioventricular valve and pulling the native atrioventricular valve radially inwards, by deflecting the chords;
• and
• subsequently, implanting the annuloplasty ring on the valve annulus, while using the arms (a) to maintain the size of the valve annulus at its decreased size, by maintaining the arms in their rotated state, and (b) to provide a counterforce against which the annuloplasty ring is pushed, by pulling the arms from beneath the valve leaflets toward the annuloplasty ring.