Apparatuses, systems, and devices usable for annuloplasty are provided. These can include an annuloplasty system comprising a segment having a lumen therethrough, the segment being positionable in a vicinity of a surface of a heart valve of a heart. The system can include a tube having a distal portion that is movable through the lumen of the segment and a distal end passable through an opening in the segment that is in fluid communication with the lumen. One or more tissue anchors are deliverable through the tube, the tissue anchor(s) being shaped so as to define a tissue coupling element. The distal portion of the tube can be removably positioned within the lumen of the segment, and, while so positioned, to deploy the tissue coupling element from the distal end of the tube in order to penetrate the tissue coupling element into cardiac tissue. Other embodiments are also described.