US Patent 8353956 Actively-engageable movement-restriction mechanism for use with an annuloplasty structure

Apparatus is provided, including a locking mechanism, an implant, and a flexible strip within the implant having a plurality of recesses. A perimeter of the strip shortens and expands when the first end of the strip is advanced bidirectionally with respect to a second end of the strip. The locking mechanism includes a moveable recess-engaging portion, a mechanical support removably coupled to the recess-engaging portion, and a force applicator which maintains the recess-engaging portion in a position in which the recess-engaging portion is not disposed in any of the recesses. Upon decoupling of the mechanical support from the recess-engaging portion, the force applicator restricts motion of the plurality of recesses of the strip with respect to the second end of the strip, by facilitating positioning of the recess-engaging portion in one of the plurality of recesses. Other embodiments are also described.