Systems and methods usable in delivering a docking device to a native valve of a patient's heart. A distal region of a delivery catheter can be positioned in an atrium of the heart and a distal tip can be positioned at or near a commissure of the native valve. The docking device can be located within the delivery catheter. A pusher, such as a pusher wire or tube, of a pusher tool can be advanced distally through the delivery catheter, wherein the pusher can push the docking device along within the delivery catheter. The docking device can be connected to the pusher tool by a line, such as a suture. A member of the pusher tool can be rotatable to change the amount of the suture extending from the pusher tool.