A delivery system for delivering an implantable fixation device to a plurality of leaflets of a heart valve, the delivery system including: the implantable fixation device having: a first arm and a second arm, a first gripping element moveable relative to the first arm between a first position and a second position, and a second gripping element moveable relative to the second arm between a first position and a second position; wherein the first arm and the second arm are positionable on opposite sides of the leaflets to the first gripping element and the second gripping element respectively; a delivery device having: a catheter having a proximal end portion and a distal end portion, the catheter defining at least one lumen extending from the proximal end portion to the distal end portion; an actuator rod passing through the catheter lumen; and a flexible cable, joined to the distal end of the actuator rod; characterised in that: the flexible cable is arranged to be disposed within the lumen, the flexible cable having a plurality of layers of wires; the flexible cable is resiliently biased to return to a substantially linear configuration after being deflected 90° or more; the flexible cable comprises an inner most layer of wires and an outermost layer of wires; and the flexible cable is connectable with the fixation device and is operable to control opening and closing of the first arm and the second arm. a first arm and a second arm, a first gripping element moveable relative to the first arm between a first position and a second position, and a second gripping element moveable relative to the second arm between a first position and a second position; a delivery device having: a catheter having a proximal end portion and a distal end portion, the catheter defining at least one lumen extending from the proximal end portion to the distal end portion; an actuator rod passing through the catheter lumen; and a flexible cable, joined to the distal end of the actuator rod; a catheter having a proximal end portion and a distal end portion, the catheter defining at least one lumen extending from the proximal end portion to the distal end portion; an actuator rod passing through the catheter lumen; and a flexible cable, joined to the distal end of the actuator rod; characterised in that: the flexible cable is arranged to be disposed within the lumen, the flexible cable having a plurality of layers of wires; the flexible cable is resiliently biased to return to a substantially linear configuration after being deflected 90° or more; the flexible cable comprises an inner most layer of wires and an outermost layer of wires; and the flexible cable is connectable with the fixation device and is operable to control opening and closing of the first arm and the second arm. the flexible cable is arranged to be disposed within the lumen, the flexible cable having a plurality of layers of wires; the flexible cable is resiliently biased to return to a substantially linear configuration after being deflected 90° or more; the flexible cable comprises an inner most layer of wires and an outermost layer of wires; and the flexible cable is connectable with the fixation device and is operable to control opening and closing of the first arm and the second arm.