Patent Publication Number: US-2020289267-A1

Title: Contraction of an annuloplasty structure

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     The present application is a continuation of PCT patent application No. PCT/IL2019/050092 filed on Jan. 23, 2019, which claims priority from U.S. Provisional Patent Application 62/621,280 to Peleg et al., filed Jan. 24, 2018, each of which is incorporated herein by reference for all purposes. 
    
    
     FIELD OF THE INVENTION 
     Some applications of the present invention relate in general to adjustment of an implant. For example, some applications of the present invention relate to contraction of a cardiovascular implant, such as an annuloplasty structure. 
     BACKGROUND 
     Ischemic heart disease causes atrioventricular valve regurgitation by the combination of ischemic dysfunction of the papillary muscles, and the dilatation of the ventricle that is present in ischemic heart disease, with the subsequent displacement of the papillary muscles and the dilatation of the valve annulus. 
     Dilation of the annulus of an atrioventricular valve can prevent the valve leaflets from fully coapting when the valve is closed. Regurgitation of blood from the ventricle into the atrium can result in increased total stroke volume and decreased cardiac output, and ultimate weakening of the ventricle secondary to a volume overload and a pressure overload of the atrium. 
     Annuloplasty, such as by implantation of an annuloplasty ring, can be used to improve leaflet coaptation by adjusting the shape of the atrioventricular valve annulus. Percutaneous (e.g., transfemoral, transseptal, etc.) annuloplasty devices can be beneficial. 
     SUMMARY OF THE INVENTION 
     This summary is meant to provide some examples and is not intended to be limiting of the scope of the invention in any way. For example, any feature included in an example of this summary is not required by the claims, unless the claims explicitly recite the features. Also, the features described can be combined in a variety of ways. The description herein relates to systems, assemblies, methods, devices, apparatuses, combinations, etc. that can be used for reshaping the heart and/or a portion thereof. Various features and steps as described elsewhere in this disclosure can be included in the examples summarized here. 
     An adjustable annuloplasty band, comprising a sleeve and a contracting wire, is contracted by tensioning the contracting wire. In an exemplary application, the resulting excess of the contraction wire is deposited within the lumen of the sleeve, obviating the need to remove the excess from the implant, e.g., by cutting. Contraction of the annuloplasty band can therefore achieved by pulling the contraction wire into and/or increasing a longitudinal proportion of the contraction wire that is disposed within the lumen. The contraction can be maintained by locking a locking mechanism to the wire. 
     For some applications, the contraction wire is pulled into the lumen from within the lumen. For some applications, the contraction wire is pulled from outside the lumen. For some applications, the contraction wire is fed into the lumen using an adjustment mechanism. 
     There is therefore provided, in an exemplary application, a system or an apparatus for use at a heart of a subject, the system/apparatus including an annuloplasty band that includes: 
     A flexible sleeve having a first sleeve-end-portion, a second sleeve-end-portion, and a circumferential wall that defines a longitudinal lumen between the first and second sleeve-end-portions. 
     An elongate contraction wire having a first wire-end and a second wire-end, the first wire-end being attached to the sleeve at the first sleeve-end-portion, and the wire extending, in association with the circumferential wall, from the first sleeve-end-portion to the second sleeve-end-portion. 
     The wire can be arranged with respect to the sleeve such that pulling the contraction wire into and/or increasing a longitudinal proportion of the wire that is disposed within the lumen longitudinally contracts the sleeve. 
     In an application, the second wire-end is disposed within the lumen, and the wire is arranged with respect to the sleeve such that movement of the second wire-end toward the first sleeve-end-portion increases the longitudinal proportion of the wire that is disposed within the lumen by drawing the wire into the lumen. 
     In an application, the system/apparatus includes a contraction tool that includes a wire-engaging element. The wire-engaging element can be movable longitudinally into the lumen and through the lumen to the second wire-end, and can be reversibly couplable (e.g., within the lumen or outside the lumen), to the second wire-end. While coupled to the second wire-end, the wire-engaging element can be movable longitudinally toward the first sleeve-end-portion, such that the second wire-end is moved toward the first sleeve-end-portion, thereby drawing the wire into the lumen and longitudinally contracting the sleeve. 
     In an application, the wire extends from the first sleeve-end-portion to the second sleeve-end-portion in association with the circumferential wall, by weaving along the circumferential wall between the first sleeve-end-portion and the second sleeve-end-portion. 
     In an application, the system/apparatus includes a one-way mechanism, coupled to the wire, configured to allow one-way movement of the wire through the one-way mechanism, and coupled to the sleeve at the second sleeve-end-portion in an arrangement that (i) allows pulling the wire into and/or increasing the longitudinal proportion of the wire that is disposed within the lumen, and (ii) inhibits reducing the longitudinal proportion of the wire that is disposed within the lumen. 
     The system/apparatus can further include an attachment means, such as a plurality of anchors. In some applications, the system/apparatus includes a plurality of anchors with each anchor of the plurality of anchors being independently advanceable into the lumen, and configured to anchor the sleeve to tissue by being driven through the circumferential wall and into tissue. In some applications, the system/apparatus includes a plurality of anchors, and each anchor of the plurality of anchors can include an anchor head and a tissue-engaging element, can be independently advanceable into the lumen, and can be configured to anchor the sleeve to tissue by the tissue-engaging element being driven through the circumferential wall and into the tissue while the anchor head remains in the lumen. 
     The system/apparatus can include a contraction tool that includes a wire-engaging element, and the wire-engaging element, subsequently to anchoring of the sleeve using the anchors. The contraction tool can be movable longitudinally into the lumen and through the lumen to the second wire-end, and can be reversibly couplable (e.g., within the lumen or outside the lumen), to the second wire-end. While coupled to the second wire-end, it can be movable longitudinally through the lumen and past the anchor heads toward the first sleeve-end-portion, such that the second wire-end is moved toward the first sleeve-end-portion, thereby drawing the wire into the lumen and longitudinally contracting the sleeve. 
     In an application, the system/apparatus includes a locking mechanism, such as a lock, etc. The locking mechanism can include an unlocked state in which the locking mechanism allows movement of the wire through the locking mechanism, and pulling the wire into and/or increasing of the longitudinal proportion of the wire that is disposed within the lumen, and a locked state in which the locking mechanism inhibits movement of the wire through the locking mechanism. 
     In an application, the locking mechanism is a component of the annuloplasty band and is coupled to the sleeve, and the annuloplasty band is transluminally-advanceable to the heart with the locking mechanism coupled to the sleeve. 
     The locking mechanism can be disposed outside of the lumen or be disposed inside the lumen. In an application, the locking mechanism is coupled to the sleeve at the second sleeve-end-portion. 
     In an application, the apparatus includes a contraction tool that includes a wire-engaging element. The wire-engaging element can be movable longitudinally into the lumen and through the lumen to the second wire-end. The wire-engaging element can also be reversibly couplable (e.g., within the lumen or outside the lumen), to the second wire-end. While coupled to the second wire-end, the wire-engaging element can be movable longitudinally toward the first sleeve-end-portion, such that the second wire-end is moved toward the first sleeve-end-portion, thereby drawing the wire into the lumen and longitudinally contracting the sleeve. 
     The locking mechanism can be coupled to the contraction tool, and can be advanceable, using the contraction tool, longitudinally through the lumen toward the second sleeve-end-portion and the wire. 
     In an application, the apparatus includes a lock tool that engages the locking mechanism, and is configured to transition the locking mechanism into the locked state. The lock tool can be configured to engage the locking mechanism outside the lumen or within the lumen. 
     In an application, the locking mechanism is biased to assume the locked state. In an application, the lock tool is configured to retain the locking mechanism in the unlocked state while the lock tool is engaged with the locking mechanism, and the lock tool is configured to transition the locking mechanism into the locked state by disengaging from the locking mechanism. 
     In an application, the annuloplasty band further includes an adjustment mechanism, the adjustment mechanism coupled to the sleeve at the second sleeve-end-portion, and coupled to the wire. The adjustment mechanism can be configured such that actuation of the adjustment mechanism increases the longitudinal proportion of the wire that is disposed within the lumen by feeding the wire into the lumen. 
     In an application, the adjustment mechanism includes a capstan. In an application, the adjustment mechanism is configured not to collect the wire upon actuation of the adjustment mechanism. 
     In an application, the apparatus further includes a guide tube, extending from the adjustment mechanism into the lumen, the actuation of the adjustment mechanism feeding the wire into the lumen by feeding the wire into the tube. 
     In an application, the apparatus further includes a guide tube, disposed within the lumen, and the actuation of the adjustment mechanism feeds the wire into the tube. 
     There is further provided, in an exemplary application, a method, the method including securing an annuloplasty band on an annulus of a valve of a subject. The annuloplasty band including (i) a flexible sleeve that defines a longitudinal lumen therethrough, and (ii) an elongate contraction wire. The method also includes subsequently, longitudinally contracting the sleeve. In an application, this is done by pulling the contraction wire into and/or increasing a longitudinal proportion of the contraction wire that is disposed within the lumen, by drawing the contraction wire into the lumen. 
     In an application, the sleeve includes a circumferential wall that defines the lumen, and securing the annuloplasty band on the annulus includes sequentially, for each anchor of a plurality of anchors: advancing the anchor into the lumen, and driving a tissue-engaging element of the anchor through the circumferential wall and into the annulus, such that an anchor head of the anchor remains in the lumen. 
     In an application, the sleeve has a first sleeve-end and a second sleeve-end, and the contraction wire has a first wire-end and a second wire-end, and longitudinally contracting the sleeve includes bringing the second wire-end closer to the first sleeve-end. 
     In an application, the method further includes, subsequently to the step of longitudinally contracting the sleeve, maintaining a contraction state of the sleeve by locking a locking mechanism to the contraction wire. The locking mechanism can be a component of the annuloplasty band, and can be coupled to the sleeve, and have an unlocked state and a locked state. 
     Securing the annuloplasty band on the annulus can include securing, to the annulus, the annuloplasty band having the locking mechanism coupled to the sleeve. 
     In an application, the step of longitudinally contracting the sleeve includes longitudinally contracting the sleeve by pulling the contraction wire into and/or increasing the longitudinal proportion of the contraction wire that is disposed within the lumen, by drawing the contraction wire into the lumen while the locking mechanism is in the unlocked state. 
     The method can further include, subsequently to longitudinally contracting the sleeve, transitioning the locking mechanism into its locked state. 
     In an application, the locking mechanism is coupled to the sleeve and is disposed outside of the lumen, and securing the annuloplasty band on the annulus includes securing, to the annulus, the annuloplasty band having the locking mechanism coupled to the sleeve and disposed outside of the lumen. 
     In an application, the method further includes advancing a wire-engaging element of a contraction tool longitudinally into and through the lumen, and coupling (e.g., within the lumen or outside the lumen), the wire-engaging element to the wire, and the step of longitudinally contracting the sleeve includes longitudinally contracting the sleeve by increasing the longitudinal proportion of the contraction wire that is disposed within the lumen, by pulling the contraction wire into the lumen using the contraction tool. 
     In an application, advancing the wire-engaging element of the contraction tool includes advancing the locking mechanism into the lumen while the locking mechanism is coupled to the contraction tool, and locking the locking mechanism to the contraction wire includes locking the locking mechanism to the contraction wire within the lumen. 
     In an application, the contraction tool includes a lock tool that maintains the locking mechanism in an unlocked state, and locking the locking mechanism to the contraction wire includes allowing the lock to transition into a locked state by disengaging the lock tool from the locking mechanism. 
     In an application, the sleeve includes a circumferential wall that defines the lumen, and securing the annuloplasty band on the annulus includes sequentially, for each anchor of a plurality of anchors: 
     advancing the anchor into the lumen, and 
     driving a tissue-engaging element of the anchor through the circumferential wall and into the annulus, such that an anchor head of the anchor remains in the lumen, and 
     advancing the wire-engaging element of the contraction tool longitudinally into and through the lumen includes advancing the wire-engaging element of the contraction tool longitudinally into and through the lumen and past the anchor heads within the lumen. 
     In an application, locking the locking mechanism to the contraction wire includes transitioning the locking mechanism into a locked state using a lock tool that is engaged with the locking mechanism outside of the lumen. 
     In an application, locking the locking mechanism to the contraction wire includes disengaging a lock tool from the locking mechanism, the locking mechanism being biased to assume a locked state, and the lock tool being configured to retain the locking mechanism in an unlocked state while the lock tool is engaged with the locking mechanism. 
     In an application, drawing the contraction wire into the lumen includes moving an end of the contraction wire longitudinally through the lumen. 
     In an application, moving the end of the contraction wire longitudinally through the lumen includes pulling the end of the contraction wire longitudinally through the lumen. 
     In an application, pulling the end of the contraction wire longitudinally through the lumen includes using a tool, coupled to the end of the contraction wire, to pull the end of the contraction wire longitudinally through the lumen. 
     In an application, moving the end of the contraction wire longitudinally through the lumen includes pushing the end of the contraction wire longitudinally through the lumen. 
     In an application, the annuloplasty band further includes an adjustment mechanism coupled to the sleeve and to the wire, and the step of longitudinally contracting the sleeve includes feeding the contraction wire into the lumen by actuating the adjustment mechanism. 
     In an application, actuating the adjustment mechanism includes actuating the adjustment mechanism using an adjustment tool, and the method further includes disengaging the adjustment tool from the adjustment mechanism subsequently to actuating the adjustment mechanism. 
     In an application, the method further includes, subsequently to securing the annuloplasty band on the annulus, and prior to actuating the adjustment mechanism, advancing the adjustment tool to the annuloplasty band and engaging the adjustment mechanism with the adjustment tool. 
     In an application, the adjustment mechanism includes a rotatable element, and actuating the adjustment mechanism includes rotating the rotatable element. 
     In an application, the rotatable element is a capstan, and rotating the rotatable element includes rotating the capstan. 
     In an application, actuating the adjustment mechanism includes actuating the adjustment mechanism without collecting the wire on the adjustment mechanism. 
     In an application, the annuloplasty band further includes a guide tube, extending from the adjustment mechanism into the lumen, and feeding the contraction wire into the lumen by actuating the adjustment mechanism includes feeding the contraction wire into the tube by actuating the adjustment mechanism. 
     There is further provided, a system or an apparatus for use at a heart of a subject, the system/apparatus comprising an annuloplasty structure that comprises a flexible sleeve having a first sleeve-end-portion, a second sleeve-end-portion, and a circumferential wall that defines a longitudinal lumen between the first and second sleeve-end-portions. The annuloplasty structure also includes an elongate contraction wire having a first wire-end and a second wire-end, the first wire-end being attached to the sleeve at the first sleeve-end-portion, and the wire extending, in association with the circumferential wall, between the first sleeve-end-portion to the second sleeve-end-portion. 
     The system/apparatus can also include an adjustment mechanism, which can be coupled to the sleeve. In some applications, the adjustment mechanism a pulley system comprising at least a first pulley and a second pulley. Though, in some applications, the pulley system can comprises at least three pulleys, at least four pulleys, at least five pulleys, at least six pulleys, or more. 
     In some applications, the system/apparatus can also include an actuator, mechanically coupled to the pulley system such that actuation of the actuator adjusts a distance between the first pulley and the second pulley. The actuator can be a linear actuator. The actuator can comprise a rotational element, and is actuated via rotation of the rotational element. 
     The wire is arranged with respect to the sleeve and the adjustment mechanism such that drawing the wire into the adjustment mechanism longitudinally contracts the sleeve. 
     In some applications, the pulley system is engaged with the wire such that increasing the distance between the first and second pulleys draws the wire into the adjustment mechanism, thereby longitudinally contracting the sleeve. 
     The pulley system and the wire can be configured to mechanically cooperate such that increasing the distance by a distance-increase amount draws, into the adjustment mechanism, a portion of the wire that is longer than the distance-increase amount, such as a portion of the wire that is at least twice as long as the distance-increase amount or more (e.g., at least four times as long, at least six times as long, etc.). 
     The pulley system and the wire can be configured to mechanically cooperate such that increasing the distance by a distance-increase amount longitudinally contracts the sleeve by a contraction length that is greater than the distance-increase amount, such as by a contraction length that is at least twice as great as the distance-increase amount or more (e.g., at least four times as great, at least six times as great, etc.). 
     There is further provided, a system or an apparatus for use at a heart of a subject, the system/apparatus including an implant having a first portion and a second portion. The implant comprises a contraction wire having a first wire-end and a second wire-end, the first wire-end being attached to the first portion, and the wire extending from the first portion to the second portion. The implant further comprises an adjustment mechanism, which can be coupled to the contraction wire. 
     In some applications, the adjustment mechanism includes a pulley system including at least a first pulley and a second pulley. 
     In some applications, the adjustment mechanism includes an actuator, mechanically coupled to the pulley system such that actuation of the actuator adjusts a distance between the first pulley and the second pulley. 
     The wire can be arranged with respect to the first portion, the second portion, and the adjustment mechanism, such that drawing the wire into the adjustment mechanism draws the first portion and the second portion closer together. In an application, the wire is arranged in a back-and-forth arrangement within the adjustment mechanism. 
     The pulley system can be engaged with the wire such that increasing the distance between the first and second pulleys draws the wire into the adjustment mechanism, thereby drawing the first portion and the second portion closer together. 
     In an application, the implant includes a flexible sleeve having a circumferential wall that defines a longitudinal lumen between the first and second portions. 
     In an application, the adjustment mechanism further includes a housing that houses the pulley system and the actuator. 
     The pulley system can include any number of pulleys. In an application, the pulley system includes at least three pulleys. The pulley system can include at least four pulleys or at least five pulleys as well. 
     In an application, the pulley system and the wire mechanically cooperate such that increasing the distance by a distance-increase amount draws, into the adjustment mechanism, a portion of the wire that is longer than the distance-increase amount. 
     In an application, the pulley system and the wire mechanically cooperate such that increasing the distance by the distance-increase amount draws, into the adjustment mechanism, a portion of the wire that is at least twice as long as the distance-increase amount. In an application, the pulley system and the wire mechanically cooperate such that increasing the distance by the distance-increase amount draws, into the adjustment mechanism, a portion of the wire that is at least four times as long as the distance-increase amount. In an application, the pulley system and the wire mechanically cooperate such that increasing the distance by the distance-increase amount draws, into the adjustment mechanism, a portion of the wire that is at least six times as long as the distance-increase amount. 
     In an application, the pulley system and the wire mechanically cooperate such that increasing the distance by a distance-increase amount draws the first portion and the second portion closer together by a contraction length that is greater than the distance-increase amount. 
     In an application, the pulley system and the wire mechanically cooperate such that increasing the distance by the distance-increase amount draws the first portion and the second portion closer together by a contraction length that is at least twice as great as the distance-increase amount. In an application, the pulley system and the wire mechanically cooperate such that increasing the distance by the distance-increase amount draws the first portion and the second portion closer together by a contraction length that is at least four times greater than the distance-increase amount. In an application, the pulley system and the wire mechanically cooperate such that increasing the distance by the distance-increase amount draws the first portion and the second portion closer together by a contraction length that is at least six times greater than the distance-increase amount. 
     In an application, the first pulley includes a first wheel and the second pulley includes a second wheel. In an application, the first wheel and the second wheel are unpowered, and are configured to rotate passively in response to the wire moving thereover. 
     In an application, the actuator is a linear actuator, and can be a leadscrew, etc. 
     In an application, the actuator includes a rotational element, and is actuated via rotation of the rotational element. 
     In an application, the system/apparatus further includes a tool that is (i) transluminally advanceable to the implant, (ii) intracorporeally reversibly engageable with the rotational element, and (iii) while engaged with the rotational element, configured to rotate the rotational element. 
     There is further provided, a system or an apparatus for use at a heart of a subject, the system/apparatus including an implant. The implant including a flexible sleeve having a first sleeve-end-portion, a second sleeve-end-portion, and a circumferential wall that defines a longitudinal lumen between the first and second sleeve-end-portions. The implant can also include a lock, coupled to the sleeve, the lock including a passive capstan. The implant includes an elongate contraction wire or other contraction element. 
     The contraction wire/element can be attached to the first sleeve-end portion, and can extend (i) from the first sleeve-end-portion to the second sleeve-end-portion in association with the circumferential wall, and (ii) through the lock, wrapping at least once around the capstan, and (iii) away from the lock and the sleeve. 
     The association between the wire and the sleeve can be such that pulling progressive regions of the wire away from the sleeve via the lock progressively longitudinally contracts the sleeve. 
     The wrapping of the contraction wire around the capstan can be such that movement of the wire through the lock rotates the capstan. 
     The lock can: 
     have a discrete unlocked state in which the capstan is rotatable, thereby facilitating movement of the wire through the lock, 
     have a discrete locked state in which rotation of the capstan is locked in at least one direction, thereby preventing movement of the wire through the lock, and 
     be reversibly switchable between the unlocked state and the locked state. 
     In an application, the lock is biased toward being in the locked state. 
     In an application, the lock further includes a mechanical resistor that is configured to partially resist movement of the wire through the lock, independent of whether the lock is in the unlocked state or the locked state. 
     In an application, in the locked state, rotation of the capstan is bidirectionally locked. In an application, in the locked state, rotation of the capstan is unidirectionally locked. 
     In an application, the implant is transluminally implantable in the heart of the subject. 
     In an application, the system/apparatus further includes an adjustment tool that is transluminally advanceable to the transluminally-implanted implant. 
     In an application, the adjustment tool is engageable with the lock, and is configured to switch the lock between the unlocked state and the locked state. 
     In an application, the tool is further configured to contract the sleeve by pulling on the wire. 
     In an application, the system/apparatus further includes a guide member that includes a flexible tube, a distal portion of the guide member reversibly coupled to the lock, the wire extends away from the lock and the sleeve via the tube, and the tool is transluminally advanceable to the transluminally-implanted implant by being advanced distally over the tube to the lock. 
     In an application, the lock further includes a housing that houses the capstan, the capstan is rotationally coupled to the housing, and movement of the wire through the lock rotates the capstan with respect to the housing. 
     In an application, in the unlocked state, the capstan is bidirectionally rotatable with respect to the housing. 
     In an application, the lock further includes at least one detent that is biased to rotationally lock the capstan with respect to the housing. 
     In an application, the at least one detent is attached to the capstan, and is configured to rotationally lock the capstan with respect to the housing, by engaging the housing. 
     In an application: the housing is shaped to define a recess, the at least one detent is configured to engage the housing by protruding into the recess, and the housing includes a button that, when pressed, switches the lock into the unlocked state by obstructing the detent from engaging the recess. 
     In an application, the at least one detent is biased to rotationally lock the capstan in a plurality of rotational positions with respect to the housing. 
     In an application, the at least one detent is a plurality of detents, each detent of the plurality of detents being biased to rotationally lock the capstan in a corresponding rotational position with respect to the housing. 
     Other features and components and steps described elsewhere herein can also be used with and/or added to the systems, apparatuses, and methods described above. 
     The present invention will be more fully understood from the following detailed description of applications thereof, taken together with the drawings, in which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A-E  are schematic illustrations of an exemplary annuloplasty system for treating a native heart valve; 
         FIGS. 2A-E  are schematic illustrations of an exemplary annuloplasty system for treating the native heart valve; 
         FIGS. 3A-D  are schematic illustrations of an exemplary annuloplasty system for treating the native heart valve; 
         FIGS. 4A-D  are schematic illustrations of an exemplary annuloplasty system for treating the native heart valve; 
         FIGS. 5A-C  are schematic illustrations of an exemplary annuloplasty system for treating the native heart valve; and 
         FIGS. 6A-D  and  7 A-E are schematic illustrations of an exemplary annuloplasty system for treating the native heart valve. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Reference is made to  FIGS. 1A-E , which are schematic illustrations of an exemplary annuloplasty system  20  that comprises an implant  22 . System  20  is for treating a native valve  10  (e.g., an atrioventricular valve, such as the mitral valve or the tricuspid valve) of a heart  4  of a subject. Any and all of the methods, techniques, steps, etc. described herein using system  20  can be performed on a living animal or on a non-living cadaver, cadaver heart, simulator, anthropomorphic ghost, etc. 
     Implant  22  comprises an implant body  24 , which can be an annuloplasty structure, such as an annuloplasty band or an annuloplasty ring. Implant body  24  comprises a flexible sleeve  25 . Sleeve  25  has a first sleeve-end-portion  42 , a second sleeve-end-portion  44 , and a circumferential wall  46 . Circumferential wall  46  can define a longitudinal lumen  48 , for example between the first and second sleeve-end-portions. Circumferential wall  46  can be made of a fabric, such as a polyethylene terephthalate fabric, e.g., Dacron™. Implant  22  further comprises an elongate contraction wire or member  26 . It is to be noted that the term “wire” is not intended to limit wire  26  to being metallic, nor to limit the number of strands that it may comprise. For some applications, contraction wire comprises one or more strands of metal. For some applications, contraction wire  26  comprises one or more strands of polymer. For some applications, contraction wire  26  is braided or woven. For some applications, contraction wire  26  is coated with a low-friction coating, such as polytetrafluoroethylene (PTFE). 
     Implant body  24  can be configured to be placed partially or completely around an annulus of valve  10 . Implant body  24  can be attached to tissue (e.g., tissue of a heart valve annulus, etc.) in a variety of ways, such as with anchors, sutures, clips, and/or other attachment means. In some embodiments, the implant body  24  is configured to be anchored in place using a plurality of (e.g.,  5 - 20 ) tissue anchors  32 . In one embodiment, each tissue anchor comprises a tissue-coupling element  34 , and a tool-engaging head  36  fastened to an end of the tissue-coupling element. In some embodiments, following introduction of implant body  24  into the subject, each anchor  32  is sequentially (and typically independently) intracorporeally delivered into the lumen of the sleeve, and its tissue-coupling element  34  is driven through the circumferential wall and into tissue of the valve annulus, thereby anchoring the sleeve to the valve annulus. Subsequent to attachment to the tissue, longitudinal contraction of implant body  24  circumferentially tightens the valve annulus, thereby improving coaptation of the valve leaflets, and reducing regurgitation. 
     For some applications, the annuloplasty structure of implant body  24  is, or shares features with, mutatis mutandis, the annuloplasty structure(s) described in one or more of the following publications, which are incorporated herein by reference. For some applications, implant  22  is implanted as described in one or more of these publications, mutatis mutandis:
         PCT application publication WO 2010/128503 to Zipory et al.   PCT application publication WO 2012/176195 to Gross et al.   PCT application publication WO 2013/069019 to Sheps et al.   PCT application publication WO 2014/064694 to Sheps et al.       

     Contraction wire  26  has a first wire-end  52  and a second wire-end  54 . In some embodiments, first wire-end  52  is attached (e.g., fixedly attached) to sleeve  25  at first sleeve-end-portion  42 , and wire  26  extends, in association with the circumferential wall of the sleeve, from the first sleeve-end-portion to second sleeve-end-portion  44 . In some embodiments, and as shown, the association between wire  26  and circumferential wall  46  is provided by the wire being woven along or as part of the circumferential wall between first sleeve-end-portion  42  and second sleeve-end-portion  44 . 
     As shown, sleeve-end-portions  42  and  44  can include more than just the very ends of sleeve  25 . Similarly, wire  26  may not extend all the way to the ends of sleeve  25 . As shown, at least one anchor  32  can be placed within at least one of sleeve-end-portions  42  and  44 , beyond wire  26 . 
     As described in more detail hereinbelow, wire  26  is arranged with respect to sleeve  25  such that pulling a longitudinal proportion of the wire into the lumen and/or increasing the amount that is disposed within the lumen longitudinally contracts the sleeve. Optionally, an end  54  of the wire  26  can be positioned inside the lumen. 
       FIG. 1lA  schematically shows implant  22  following its implantation at valve  10 , with the tissue-coupling element  34  of each anchor  32  extending through the circumferential wall of sleeve  25  and into the annulus of the valve. For the sake of clarity, the tissue into which tissue-coupling elements  34  penetrates is not shown. As shown, second wire-end  54  can be disposed within the lumen of sleeve  25  prior to and/or during implantation, or can be disposed outside the lumen but be pullable into the lumen. For some applications, and as shown, system  20  further comprises an elongate guide member  28 , reversibly coupled to second wire-end  54 , and extending proximally though the lumen of sleeve  25 , and proximally away from implant  22  (e.g., out of the subject). 
     Following implantation of implant  22 , a contraction tool  60  is used to facilitate contraction of the implant. Contraction tool  60  comprises a wire-engaging element  62 , which is movable longitudinally into lumen  48 , and through the lumen to second wire-end  54 . Such movement is shown in  FIG. 1B . For applications in which implant body  24  is anchored using anchors  32 , tool  60  is dimensioned to be advanceable through lumen  48  past anchor heads  36  already disposed within the lumen. 
     Wire-engaging element  62  is reversibly couplable, e.g., within lumen  48 , to second wire-end  54 . Such coupling is shown in  FIG. 1C . Implant  22  can comprise an appendage  55  coupled to second wire-end  54  of contraction wire  26 , wire-engaging element  62  and appendage  55  being mutually configured to facilitate the reversible coupling of the wire-engaging element to the second wire-end of the contraction wire. While coupled to second wire-end  54 , wire-engaging element  62  is movable longitudinally toward first sleeve-end-portion  42  (e.g., by being pulled proximally), such that the second wire-end is moved toward the first sleeve-end-portion, thereby drawing contraction wire  26  into lumen  48 , and longitudinally contracting sleeve  25  ( FIG. 1D ). 
     System  20  further comprises a locking mechanism  70 , coupled to contraction tool  60 , and advanceable, using the contraction tool, longitudinally through lumen  48  toward second sleeve-end-portion  44  and contraction wire  26  (e.g., as shown in  FIGS. 1B-C ). In some embodiments, locking mechanism  70  has (i) an unlocked state in which the locking mechanism allows movement of contraction wire  26  through the locking mechanism, and increasing of the longitudinal proportion of the wire that is disposed within the lumen, and (ii) a locked state in which the locking mechanism inhibits movement of the wire through the locking mechanism. 
     Once a desired amount of contraction of sleeve  25  has been achieved by drawing contraction wire  26  into lumen  48  (and through locking mechanism  70 ), locking mechanism  70  is locked, e.g., using tool  60 , which thereby also serves as a lock tool  64  that engages locking mechanism  70  within lumen  48 . The locking of locking mechanism  70  inhibits the contraction wire from moving back out of the lumen, and therefore maintaining the desired amount of contraction of the sleeve. For example, locking mechanism  70 , locked to contraction wire  26 , may be too large to exit lumen  48  via the hole through which wire  26  entered the lumen at second sleeve-end-portion  44 . 
     Tool  60  may then be decoupled from wire  26 , and removed from implant  22  ( FIG. 1E ). For applications in which system  20  comprises guide member  28 , the guide member is also decoupled from implant  22 , e.g., facilitated by tool  60 . 
     It is to be noted that the resulting excess  56  of wire  26  (i.e., the part of the wire that has passed through locking mechanism  70  and does not serve to maintain the contraction of sleeve  25 , e.g., the part of the wire that is not under tension) is disposed within lumen  48 . The inventors hypothesize that this, in contrast to a hypothetical similar implant in which the excess of the contraction wire is disposed outside of sleeve  25 , advantageously does not require removal of the excess of the contraction wire (e.g., by cutting). 
     Reference is now made to  FIGS. 2A-E , which are schematic illustrations of an annuloplasty system  120  for treating native valve  10 , in accordance with some applications of the invention. System  120  comprises an implant  122 , which comprises implant body  24  (comprising sleeve  25 ) and contraction wire  26 , e.g., as described hereinabove, mutatis mutandis. Typically, except where noted, implant  122  and the implantation thereof are as described hereinabove for implant  22  and its implantation, mutatis mutandis. 
     As described for implant  22 , wire  26  of implant  122  can be arranged with respect to sleeve  25  such that pulling wire  26  into the lumen and/or increasing a longitudinal proportion of the wire that is disposed within the lumen longitudinally contracts the sleeve. 
       FIGS. 2A-E  show system  120  not comprising a guide member such as guide member  28 , described hereinabove. However, in some embodiments, system  120  may in fact comprise a guide member, and/or system  20  may not comprise a guide member. 
     System  120  comprises a locking mechanism  170 . However, in contrast to locking mechanism  70  of system  20 , locking mechanism  170  of system  120  is a component of implant  122 , and implant  122  is transluminally-advanceable to the heart with the locking mechanism coupled to sleeve  25 , typically at second sleeve-end-portion  44 . In some embodiments, at least part of (e.g., all of) locking mechanism  170  is disposed outside of lumen  48 . 
     System  120  comprises a lock tool  164  that engages locking mechanism  170 , and is configured to transition the locking mechanism into the locked state. However, in contrast to lock tool  164  of system  20 , lock tool  164  of system  120  engages locking mechanism  170  outside lumen  48 . For some applications, locking mechanism  170  is biased to assume its locked state, and lock tool  164  is configured to retain the locking mechanism in its unlocked state while the lock tool is engaged with the locking mechanism. For such applications, disengagement of lock tool  164  from locking mechanism  170  allows the locking mechanism to transition into its locked state. Other locking mechanisms and lock tools described herein may also operate in this manner, mutatis mutandis. 
       FIG. 2A  schematically shows implant  122  following its implantation at valve  10 , with the tissue-coupling element  34  of each anchor  32  extending through the circumferential wall of sleeve  25  and into the annulus of the valve. For the sake of clarity, the tissue into which tissue-coupling elements  34  penetrates is not shown. In some embodiments, as shown, second wire-end  54  is disposed within the lumen of sleeve  25  prior to and/or during implantation. 
     Following implantation of implant  122 , a contraction tool  160  is used to facilitate contraction of the implant. Contraction tool  160  comprises a wire-engaging element  162 , which is movable longitudinally into lumen  48 , and through the lumen to second wire-end  54 , to which it is then reversibly coupled ( FIG. 2B ). For applications in which implant body  24  is anchored using anchors  32 , tool  160  is dimensioned to be advanceable through lumen  48  past anchor heads  36  already disposed within the lumen. 
     While coupled to second wire-end  54 , wire-engaging element  162  is movable longitudinally toward first sleeve-end-portion  42  (e.g., by being pulled proximally), such that the second wire-end is moved toward the first sleeve-end-portion, thereby drawing contraction wire  26  into lumen  48 , and longitudinally contracting sleeve  25  ( FIG. 2C ). 
     During the contraction of sleeve  25 , locking mechanism  170  is in its unlocked state, e.g., maintained in the unlocked state by lock tool  164 . Once a desired amount of contraction of sleeve  25  has been achieved by drawing contraction wire  26  into lumen  48  (and through locking mechanism  170 ), locking mechanism  170  is locked, e.g., using lock tool  164 , typically by disengaging the lock tool from the locking mechanism ( FIG. 2D ). Tool  160  (e.g., wire-engaging element  162  thereof) can then be decoupled from wire  26 , and removed from implant  22  (FIG.  2 E). The resulting excess  56  of wire  26  is advantageously disposed within lumen  48 , e.g., as described hereinabove for system  20 , mutatis mutandis. 
     Reference is now made to  FIGS. 3A-D , which are schematic illustrations of an annuloplasty system  220  for treating native valve  10 , in accordance with some applications of the invention. System  220  comprises an implant  222 , which comprises implant body  24  (comprising sleeve  25 ) and contraction wire  26 , e.g., as described hereinabove, mutatis mutandis. Typically, except where noted, implant  222  and the implantation thereof are as described hereinabove for implant  22  and/or implant  122 , mutatis mutandis. 
     As described for implants  22  and  122 , wire  26  of implant  222  is arranged with respect to sleeve  25  such that pulling the wire  26  into the lumen and/or increasing a longitudinal proportion of the wire that is disposed within the lumen longitudinally contracts the sleeve. 
     Implant  222  comprises an adjustment mechanism  280  coupled to implant body  24  (e.g., to sleeve  25 ), for example at second sleeve-end-portion  44 . Adjustment mechanism  280  is coupled to contraction wire  26 , and is configured such that actuation of the adjustment mechanism increases the longitudinal proportion of the wire that is disposed within lumen  48  by feeding the wire into the lumen. For some applications, adjustment mechanism  280  is disposed outside of lumen  48 . For some applications, adjustment mechanism  280  is disposed within lumen  48  or partially within the lumen. Typically, adjustment mechanism  280  is configured not to collect contraction wire  26  upon actuation of the adjustment mechanism. That is, actuation of adjustment mechanism  280  typically does not cause contraction wire  26  to collect on or in the adjustment mechanism. Rather, adjustment mechanism  280  moves contraction wire  26  from one side of the adjustment mechanism to the other side of the adjustment mechanism. For some applications, adjustment mechanism  280  is actuated by rotation. For example, and as shown in  FIG. 3A , adjustment mechanism  280  can comprise a capstan  282 , e.g., disposed within a housing  284 . Whereas rotation of a spool would cause contraction wire  26  to collect upon the spool, rotation of capstan  282  does not collect the contraction wire, but instead a constant number of turns of the contraction wire around the capstan is maintained as the contraction wire is fed from one side of the capstan to the other. 
     It is hypothesized by the inventors that another particular advantage of using a capstan is that because the number of turns of the wire around the capstan is maintained, the amount of contraction induced per revolution of the capstan remains constant. 
     For some applications, implant  222  further comprises a guide tube  286 , at least part of which is disposed within lumen  48 . For example, guide tube  286  may extend from adjustment mechanism  280  into lumen  48 . Guide tube  286  is narrower than sleeve  25 . Actuation of adjustment mechanism  280  feeds contraction wire  26  into guide tube  286 . For some applications, guide tube  286  is lined with a low-friction lining such as PTFE, to facilitate sliding of wire  26  through the tube. It is hypothesized by the inventors that tube  286  advantageously facilitates sliding of second wire-end  54  through lumen  48  toward first sleeve-end-portion  42 . 
       FIG. 3A  schematically shows implant  222  following its implantation at valve  10 , with the tissue-coupling element  34  of each anchor  32  extending through the circumferential wall of sleeve  25  and into the annulus of the valve. For the sake of clarity, the tissue into which tissue-coupling elements  34  penetrates is not shown. In some embodiments, as shown, second wire-end  54  is disposed within the lumen of sleeve  25  prior to and/or during implantation. 
     Following implantation of implant  222 , a contraction tool  260  is used to facilitate contraction of the implant by actuating adjustment mechanism  280 . For applications in which adjustment mechanism  280  is actuated by rotation, contraction tool  260  comprises a rotation tool. 
     For some applications, implant  222  is implanted with contraction tool  260  coupled thereto (e.g., engaging adjustment mechanism  280 ). 
     For some applications, and as shown, system  220  can comprise an elongate guide member  228 , reversibly coupled to implant  222  (e.g., to adjustment mechanism  280 ), and extending proximally away from implant  222  (e.g., out of the subject). Subsequent to implantation of implant  222 , contraction tool  260  is advanced along (e.g., over) guide member  228  to adjustment mechanism  280  ( FIG. 3B ). While engaged with adjustment mechanism  280 , contraction tool  260  actuates the adjustment mechanism, feeding contraction wire  26  into lumen  48  (e.g., into tube  286 ), typically moving second wire-end  54  toward first sleeve-end-portion  42  ( FIG. 3C ). 
     Subsequently, contraction tool  260  is disengaged from adjustment mechanism  280 , and is removed from the subject ( FIG. 3D ). As shown, guide member  228 , if used, is also decoupled from implant  222  (e.g., from adjustment mechanism  280 ) and removed from the subject. For some applications, contraction tool  260  is used to decouple guide member  228  from the implant. 
     For some applications, system  220  comprises a locking mechanism  270 . In contrast to locking mechanism  70 , and similar to locking mechanism  170 , locking mechanism  270  of system  220  is a component of implant  222 , and implant  222  is transluminally-advanceable to the heart with the locking mechanism coupled to sleeve  25 , typically at second sleeve-end-portion  44 . In some embodiments, locking mechanism  270  is coupled to adjustment mechanism  280 , and can also be disposed within housing  284 . In its unlocked state, locking mechanism  270  typically allows movement of contraction wire  26  into lumen  48  by allowing actuation of adjustment mechanism  270 . In its locked state, locking mechanism  270  can inhibit movement of contraction wire  26  into lumen  48  by inhibiting actuation of adjustment mechanism  270 . 
     For some applications, contraction tool  260  comprises or serves as a lock tool  264 , and is configured to transition locking mechanism  270  into the locked state. For some applications, locking mechanism  270  is biased to assume its locked state, and lock tool  264  is configured to retain the locking mechanism in its unlocked state while the lock tool is engaged with the locking mechanism and/or adjustment mechanism  280 . 
     Reference is now made to  FIGS. 4A-D , which are schematic illustrations of an annuloplasty system  320  for treating native valve  10 , in accordance with some applications of the invention. Except where noted, system  320  and its components are typically the same as system  20  and correspondingly-named components, mutatis mutandis. System  320  comprises an implant  322 , which comprises implant body  24  (comprising sleeve  25 ) and a contraction wire  326 , e.g., as described hereinabove, mutatis mutandis. Contraction wire  326  is similar to contraction wire  26 , except that it extends proximally away from sleeve  25 . 
       FIG. 4A  schematically shows implant  322  following its implantation at valve  10 , with the tissue-coupling element  34  of each anchor  32  extending through the circumferential wall of sleeve  25  and into the annulus of the valve. For the sake of clarity, the tissue into which tissue-coupling elements  34  penetrates is not shown. For some embodiments, as shown, contraction wire  326  extends through lumen  48  toward and past first sleeve-end-portion  42 , and proximally away from the sleeve  25 , such that second wire-end  54  is typically disposed outside of the subject. 
     Following implantation of implant  322 , a contraction tool  360  is used to facilitate contraction of the implant. Contraction tool  360  is slid distally over contraction wire  326  toward implant  322  ( FIG. 4B ). Contraction wire  326  is pulled proximally, thereby contracting sleeve  25  ( FIG. 4C ). Contraction tool  360  can provide an opposing force against the proximal end of sleeve  25 . 
     System  320  further comprises a locking mechanism  370  (e.g., a lock, etc.), coupled to contraction tool  360 , and advanceable, using the contraction tool, longitudinally along contraction wire  326  to implant  322 . Locking mechanism  370  has (i) an unlocked state in which the locking mechanism allows movement of contraction wire  326  through the locking mechanism, and (ii) a locked state in which the locking mechanism inhibits movement of the wire through the locking mechanism. Once a desired amount of contraction of sleeve  25  has been achieved, locking mechanism  370  is locked, e.g., using tool  360 , which thereby also serves as a lock tool  364 . The locking of locking mechanism  370  inhibits the contraction wire from returning, and therefore maintains the desired amount of contraction of sleeve  25 . For example, locking mechanism  370 , locked to contraction wire  326 , may be too large to enter lumen  48 . Tool  360  can then cut excess  356  of wire  326 , and be removed from implant  22  ( FIG. 1E ). 
     It is to be noted that, unlike in systems  20 ,  120 , and  220 , in system  320  the excess  356  of contraction wire  326  that results from contracting sleeve  25  is disposed outside of lumen  48  of the sleeve and, therefore, can be cut in order to avoid this loose portion of the wire from moving freely within the heart. 
     It is to be noted that, unlike for contraction wire  26  of systems  20 ,  120 , and  220 , the proximal portion of contraction wire  326  of system  320  serves as a guide member along which the adjustment tool can be advanced toward the implant. 
     Reference is again made to  FIGS. 1A-4D . For some applications of the invention, the locking mechanism of a given system can be replaced with a one-way mechanism such as a ratchet, mutatis mutandis. The one-way mechanism would be coupled to the contraction wire, and to the sleeve at the second sleeve-end-portion, and would be configured to allow one-way movement of the wire through the one-way mechanism. The system would be arranged such that the one-way mechanism (i) allows increasing the longitudinal proportion of the wire that is disposed within the lumen, and (ii) inhibits reducing the longitudinal proportion of the wire that is disposed within the lumen. 
     Reference is now made to  FIGS. 5A-C , which are schematic illustrations of an annuloplasty system  420  for treating native valve  10 , in accordance with some applications of the invention. Except where noted, system  420 , including its components and implantation, are typically the same as system  20 , correspondingly-named components, and its implantation, mutatis mutandis. System  420  comprises an implant  422 , which comprises implant body  24  (comprising sleeve  25 ) and contraction wire  26 , e.g., as described hereinabove, mutatis mutandis. 
       FIG. 5A  schematically shows implant  422  following its implantation at valve  10 . Implant  422  is shown attached with the tissue-coupling element  34  of each anchor  32  extending through the circumferential wall of sleeve  25  and into the annulus of the valve, but other attachment means (e.g., sutures, clips, etc.) are also possible. For the sake of clarity, the tissue into which tissue-coupling elements  34  penetrates is not shown. First wire-end  52  is typically attached (e.g., fixedly attached) to sleeve  25  at first sleeve-end-portion  42 , and wire  26  extends, in association with the circumferential wall of the sleeve, from the first sleeve-end-portion to second sleeve-end-portion  44 . In some embodiments, as shown, the association between wire  26  and circumferential wall  46  is provided by the wire being woven along or as part of the circumferential wall between first sleeve-end-portion  42  and second sleeve-end-portion  44 . 
     Implant  422  comprises an adjustment mechanism  480  coupled to implant body  24  (e.g., to sleeve  25 ), for example at second sleeve-end-portion  44 . Wire  26  is arranged with respect to sleeve  25  and adjustment mechanism  480  such that drawing the wire into the adjustment mechanism longitudinally contracts the sleeve (e.g., drawing portions  42  and  44  closer together). For some applications, as shown, adjustment mechanism  480  is disposed outside of lumen  48 . For some applications, adjustment mechanism  480  is disposed within lumen  48  or partially within the lumen. 
     Adjustment mechanism  480  comprises a pulley system  482  and an actuator  486 . For some applications, adjustment mechanism  480  further comprises a housing  488  that houses pulley system  482  and/or actuator  486 . For applications in which adjustment mechanism  480  comprises housing  488 , actuator  486  (e.g., an actuator interface  496  thereof) is typically accessible from outside of the housing. Although adjustment mechanism  480  is shown as being disposed outside of sleeve  25 , for some applications the adjustment mechanism is disposed within the lumen of the sleeve. 
     Pulley system  482  comprises a plurality of pulleys  484  that comprises at least a first pulley  484   a  and a second pulley  484   b.  Actuator  486  is typically coupled to pulley system  482  such that actuation of the actuator adjusts a distance between pulleys  484   a  and  484   b.  Pulley system  482  is engaged with wire  26  such that increasing the distance between the first and second pulleys draws the wire into adjustment mechanism  480  (e.g., into housing  488  thereof), thereby longitudinally contracting the sleeve. Therefore, in contrast to adjustment mechanism  280 , adjustment mechanism  480  is configured to collect wire  26  upon actuation. It is to be noted, however, that although wire  26  is collected within adjustment mechanism  480 , the wire is not collected by increasing wrapping of the wire around the pulleys of the adjustment mechanism.  FIG. 5C  shows the initial position of pulley  484   a  in phantom, and the adjusted position of  484   a  in regular lines. The amount that the distance between pulleys  484   a  and  484   b  has been increased by actuation of adjustment mechanism  480  is shown as a distance-increase amount d 1 . 
     Typically, pulley system  482  and wire  26  mechanically cooperate such that increasing the distance between pulleys  484   a  and  484   b  by distance-increase amount d 1  draws, into the adjustment mechanism, a portion of the wire that is longer than distance-increase amount d 1 , thereby typically longitudinally contracting sleeve  25  by a contraction length d 2  (shown in  FIG. 5C ) that is greater than the distance-increase amount. In some embodiments, this is achieved by wire  26  being arranged, within the adjustment mechanism (e.g., within the pulley system, such as between pulleys  484 ) in a back-and-forth arrangement that multiplies distance-increase amount. 
     For some applications, pulley system  482  and wire  26  mechanically cooperate such that the portion of the wire that is drawn into adjustment mechanism  480  is at least twice as long (e.g., at least four times as long, such as at least six times as long), e.g., 2-10 times as long as distance-increase amount. For some applications, pulley system  482  and wire  26  mechanically cooperate such that contraction length d 2  is at least twice as long (e.g., at least four times as long, such as at least six times as long), e.g., 2-10 times as long as distance-increase amount. 
     For some applications, pulley system  482  comprises at least  3  pulleys  484 , e.g., with at least 3 (such as at least 4) wire-parts of wire  26  arranged in a back-and-forth arrangement. For some applications, pulley system  482  comprises at least  4  pulleys, e.g., with at least 4 (such as at least 5) wire-parts of wire  26  arranged in a back-and-forth arrangement. For some applications, pulley system  482  comprises at least 5 pulleys, e.g., with at least 5 (such as at least 6) wire-parts of wire  26  arranged in a back-and-forth arrangement.  FIGS. 5A-C  show an embodiment in which pulley system  482  comprising 5 pulleys  484  (labeled  484   a - e ) with 6 wire-parts of wire  26  arranged in a back-and-forth arrangement. The wire-parts of wire are labeled  26   a - f.  For this embodiment, distance-increase amount is multiplied about 6 times, as each wire-part is lengthened by the distance-increase amount. That is, the portion of wire that is drawn into adjustment mechanism  480 , and/or contraction length d 2 , is about 6 times as long as distance-increase amount d 1 . 
     For some applications, and as shown, pulley system  482  is similar to a block-and-tackle arrangement used for lifting heavy loads, where each pulley  484  is mounted on one or other of two frames  490 , such that each frame and the pulley(s) mounted on it collectively define a respective “block”  492 . However, for a regular block-and-tackle, the load is typically attached to one of the blocks, and the applied force is input via the “rope”—by pulling the rope in order to move the blocks together, a mechanical advantage is provided, amplifying force by sacrificing distance moved. In contrast, for adjustment mechanism  480 , the applied force is input via the blocks—by moving the blocks apart, the amount of wire drawn into the adjustment mechanism is amplified. 
     For embodiments in which pulleys  484  are mounted on one or other of two frames to define blocks, distance-increase d 1 , which is generally defined hereinabove as the increase in distance between pulleys, is the same as the increase in distance between the two blocks (or the two frames thereof). In the embodiment shown, pulleys  484   a,    484   c,  and  484   e  are mounted to a first frame  490   a,  thereby defining a first block  492   a,  and pulleys  484   b  and  484   d  are mounted to a second frame  490   b,  thereby defining a second block  492   b.  Therefore distance-increase d 1  may be defined as the increase in distance between pulleys (e.g., pulleys  484   a  and  484   b ), the increase in distance between frames  490   a  and  490   b,  and/or the increase in distance between blocks  492   a  and  492   b.    
     Each of pulleys  484  typically comprises a wheel, e.g., that rotates passively in response to wire  26  moving thereover. However, each pulley  484  can comprise a different suitable bearing, including, for example, a smooth curved surface that does not rotate. For example, each bearing can be a fixed pin over which the wire is slidable. 
     Actuator  486  can be a linear actuator. For some applications, and as per the embodiment shown, actuator  486  comprises a rotational element, and is actuated by application of a rotational force to rotate the rotational element. For example, and as shown, the rotational element can comprise a leadscrew  494 , rotation of which moves one of blocks  492  linearly with respect to the other block. 
     As described hereinabove, pulley system  482  draws in a length of wire  526  that is greater than the distance that the pulleys and/or blocks move apart. Therefore, whereas a regular block- and tackle amplifies force by sacrificing distance, adjustment mechanism  480  (e.g., pulley system  482  thereof) typically amplifies distance by sacrificing force. It is hypothesized by the inventors that it is therefore advantageous to combine pulley system  482  with an actuator that provides a mechanical advantage in order to facilitate application, to the pulley system (e.g., to block  492   a  thereof) of a force of sufficient magnitude to contract implant  422  and the tissue to which it is anchored. It is hypothesized by the inventors that actuator  486 , comprising leadscrew  494 , is such an actuator. 
     Following implantation of implant  422 , an adjustment tool (e.g., a contraction tool)  460  is advanced (e.g., transluminally) to the implanted implant, where it engages adjustment interface  496  of adjustment mechanism  480  ( FIG. 5B ). Tool  460  is used to actuate adjustment mechanism  480  via interface  496  (e.g., by inducing rotation of leadscrew  494 ), thereby causing contraction of implant  422  ( FIG. 5C ). For applications in which implant  422  comprises an annuloplasty structure implanted at the native valve annulus, this contraction results in reshaping of the native valve annulus. 
     For some applications, and as shown, in system  420  (i.e., in implant  422 ), both ends of contraction wire  26  remain fixed in position (e.g., with respect to sleeve  25 ) irrespective of the adjustment of the implant. For example, first wire-end  52  can be attached (e.g., fixedly attached) to sleeve  25  at first sleeve-end-portion  42 , and second wire-end  54  can be attached (e.g., fixedly attached) to a component of adjustment mechanism  480  that does not move with respect to sleeve  25  upon actuation—such as frame  490   b  (as shown) or housing  488 . Optionally, second wire-end can be attached (e.g., fixedly attached) to a component of adjustment mechanism  480  that does move with respect to sleeve  25  upon actuation—such as frame  490   a.    
     Reference is now made to  FIGS. 6A-D  and  7 A-E, which are schematic illustrations of an exemplary annuloplasty system  520  for treating native valve  10 . Except where noted, system  520  and its components are typically the same as system  20 , including correspondingly-named components and its implantation, mutatis mutandis. System  520  comprises an implant  522 , which comprises implant body  24  (comprising sleeve  25 ) and a contraction wire  526 , e.g., as described hereinabove, mutatis mutandis. Contraction wire  526  is similar to contraction wire  26 , except that it extends proximally away from sleeve  25 , as described in more detail hereinbelow. Implant  522  further comprises a lock  570  coupled to implant body  24  (e.g., to sleeve  25 ), for example at second sleeve-end-portion  44 . 
       FIGS. 6A-D  show lock  570  and its association with wire  526 , and  FIGS. 7A-E  show at least some steps in the use of system  520 , in accordance with some applications of the invention. The association between wire  526  and sleeve  25  is such that pulling progressive regions of the wire away from the sleeve via lock  570  progressively longitudinally contracts the sleeve (e.g., drawing portions  42  and  44  closer together). For some applications, and as shown, lock  570  is disposed outside of lumen  48  of sleeve  25 . For some applications, adjustment mechanism  480  is disposed within lumen  48  or partially within the lumen. 
       FIG. 7A  schematically shows implant  422  following its implantation at valve  10 .  FIG. 7A  depicts implant  422  with the tissue-coupling element  34  of each anchor  32  extending through the circumferential wall of sleeve  25  and into the annulus of the valve, but other attachment means (e.g., sutures, clips, etc.) are also possible. For the sake of clarity, the tissue into which tissue-coupling elements  34  penetrates is not shown. First wire-end  52  is typically attached (e.g., fixedly attached) to sleeve  25  at first sleeve-end-portion  42 , and wire  526  extends, in association with the circumferential wall of the sleeve, from the first sleeve-end-portion to second sleeve-end-portion  44 . In some embodiments, as shown, the association between wire  26  and circumferential wall  46  is provided by the wire being woven along or as part of the circumferential wall between first sleeve-end-portion  42  and second sleeve-end-portion  44 . 
     Lock  570  comprises a passive capstan  572 . Lock  570  can also comprise a housing  574  that houses the capstan, the capstan being rotationally coupled to the housing (e.g., rotationally mounted within the housing). Wire  526  extends (i) from first sleeve-end-portion  42  to second sleeve-end-portion  44  in association with the circumferential wall of sleeve  25 , (ii) through lock  570 , wrapping at least once around capstan  572 , and (iii) away from the lock and the sleeve. As shown in  FIG. 7A , implant  522  is implanted in this state, such that wire  526  extends proximally away from the implantation site, typically out of the subject. Typically, wire  526  wraps at least twice around capstan  572 . In the example shown, wire  526  wraps three full turns around capstan  572 . 
     Typically, system  520  comprises a guide member  530  that comprises a flexible tube  532 . A distal portion  534  of guide member  530  is reversibly coupled to lock  570 , and wire  526  extends away from the lock and the sleeve via the tube. This is illustrated, inter alia, in  FIGS. 6A and 6D . For some applications, and as shown, the coupling between portion  534  and lock  570  is a screw coupling. Implant  522  can be implanted in this state, e.g., as shown in  FIG. 7A . 
     The wrapping of wire  526  around capstan  572  is such that movement of the wire through lock  570  rotates the capstan. While not wishing to be constrained by a particular theorem, it is hypothesized by the inventors that this is due to belt friction. It is to be noted that the term “passive capstan” (including the specification and the claims) means a capstan that rotates passively in response to movement of wire  526 , e.g., as opposed to a capstan that is actively rotated in order to pull the wire. 
     Lock  570  has discrete unlocked and locked states, and is reversibly switchable between the unlocked state and the locked state. In the unlocked state capstan  572  is rotatable (e.g., with respect to housing  574  and/or with respect to sleeve  25 ), thereby facilitating movement of the wire through the lock. In the locked state, rotation of capstan  572  is locked in at least one direction, thereby preventing movement of the wire through the lock. Again, while not wishing to be constrained by a particular theorem, it is hypothesized by the inventors that this prevention of movement of the wire is due to belt friction. 
     Typically, lock  570  is biased toward being in the locked state, though it need not be. 
     For some applications, and as shown, the rotational locking of capstan  572  is provided by at least one detent  580 . For such applications in which lock  570  is biased toward being in the locked state, the at least one detent can be biased to rotationally lock capstan  572  with respect to housing  574 . 
     For some applications, and as shown, the at least one detent  580  is attached to capstan  572 , and is configured to rotationally lock the capstan with respect to housing  574  by engaging the housing. For example, housing  574  can be shaped to define a recess  576 , and the at least one detent  580  can be configured to engage the housing by protruding into the recess. 
     Following implantation of implant  522 , an adjustment tool  560  is transluminally advanced to the implant ( FIG. 7B ). In some embodiments, tool  560  is advanced over and along proximal portions of wire  526 . For applications in which system  520  comprises guide member  530 , tube  532  is already disposed over wire  526 , and tool  560  is advanced over and along tube  532  (as well as over and along wire  526  therewithin). 
     Tool  560  engages lock  570 , and is used to switch the lock into the unlocked state ( FIG. 7C ). For example, tool  560  may push detent  580  out of recess  576 , and/or may obstruct the at least one detent from engaging the recess. For some applications, and as shown, housing  574  comprises a button  578  that, when pressed, switches the lock into the unlocked state by obstructing the detent from engaging the recess. For such applications, tool  560  can press button  578 —e.g., as shown. 
     Subsequently, wire  526  is pulled proximally away from sleeve via the lock, thereby longitudinally contracting implant  522  ( FIG. 7D ). As shown, detent  580  rotates in response to the movement of wire  526 . For some applications, tool  560  (e.g., a proximal portion thereof) is configured to pull wire  526 . For some applications, wire  526  is pulled via a different means, e.g., with tool  560  serving merely to unlock lock  570  and to provide a counter-force to facilitate pulling of the wire. 
     Once a desired degree of contraction is achieved, lock  570  is switched to the locked state ( FIG. 7E ). For example, for applications in which lock  570  is biased toward being in the locked state, the lock can simply be allowed to automatically return to the locked state—e.g., by releasing button  578 . At this stage, tool  560  can be removed from the subject (e.g., as shown in  FIG. 7E ). Optionally, further adjustment of the contraction of implant  522  can be performed by repeating the previous steps, mutatis mutandis. 
     In some embodiments, after contraction of implant  522 , excess wire  526  is removed. For example, tool  560  can comprise a cutter, or a dedicated cutter can be used—e.g., advanced over and along wire  526  (and/or guide member  530 , if guide member  530  is still present). 
     Typically, after contraction of implant  522 , guide member  530  is decoupled (e.g., unscrewed) from lock  570 , and removed from the subject. This is illustrated by the absence of the guide member in  FIG. 7E . For some applications, guide member  530  is removed simultaneously with tool  560 . For some applications, guide member  530  is left in place for at least some time after tool  560  is removed, e.g., to facilitate re-adjustment and/or to facilitate advancement of a cutter for removal of excess wire  526 . 
     For some applications, in the locked state, rotation of the capstan is bidirectionally locked. Optionally, and as shown, in the locked state, rotation of the capstan is unidirectionally locked, e.g., such that wire  526  can pass proximally through lock  570  to contract implant  522 , but cannot pass back again. In the unlocked state, capstan  572  can be bidirectionally rotatable. 
     For some applications, and as shown, lock  570  is configured to be lockable in any of a plurality of rotational positions of capstan  572 . Therefore, for some applications, the at least one detent  580  is biased to rotationally lock capstan  572  in a plurality of rotational positions with respect to housing  574 . For example, and as shown, lock  570  can comprise a plurality of detents  580 , each biased to rotationally lock capstan  572  in a corresponding rotational position with respect to the housing. In the example shown, lock  570  comprises three detents  580  distributed around capstan  572 , providing three rotational locking positions at 120-degree intervals. 
     For some applications, lock  570  further comprises a mechanical resistor  590  that is configured to partially resist movement of the wire through the lock, independent of whether the lock is in the unlocked state or the locked state. It is hypothesized by the inventors that resistor  590  provides greater control over wire  526 , e.g., by maintaining tensions of the wire wrapped around the capstan. Resistor  590  can be provided in one of many forms, but in the example shown, the resistor is a bar that is pressed against wire  526  by a spring  592 . 
     It is to be noted that although wire  526  is wrapped around capstan  572 , this wrapping is not increased during contraction of sleeve  25 . Wire  526  is not collected within lock  570  during contraction of sleeve  25 . 
     It is hypothesized by the inventors that lock  570  provides at least two advantages, e.g., compared to some other locking mechanisms. Firstly, the amount of contact between lock  570  (e.g., capstan  572  thereof) and wire  526  typically remains constant at all times, irrespective of whether lock  570  is in the locked or unlocked state, and irrespective of a degree of contraction of sleeve  25 . Therefore the “locking” is, in effect, locking between two components of lock—e.g., as opposed to an induced locking of a component of the lock to the wire. Secondly, lock  570  provides a large amount of contact with wire  526 , and therefore the locking force applied by the lock to the wire is spread over a larger surface area of the wire compared to a lock that might contact the wire over a smaller surface area, such as a crimpable bead. It is hypothesized that these features advantageously increase control, reliability, and safety. 
     Methods involving the systems and devices herein can include any of the steps described above, e.g., to implant, attach, contract, lock, etc. the systems, devices, components, etc. In some embodiments, methods involve transvascularly (e.g., transfemorally, etc.) advancing the system, device, implant, etc. to a target location, such as a heart valve annulus or simulation of a heart valve annulus. The methods involve attaching the system, device, implant, etc. to the target location (e.g., after advancement as described previously). Attaching can involve anchoring, suturing, clipping, and/or using other attachment means to attach the system, device, implant, etc. to the target location. The methods also involve contracting the system, device, implant, etc., which can be done by pulling or otherwise exerting force on a contraction wire (which can be attached, configured, and/or arranged as described in any of the embodiments above) to cause the system, device, implant, etc. to contract (e.g., to a contracted configuration with a smaller length, diameter, and/or radius of curvature). The contracting can be done as described with respect to any of the embodiments above. The methods can also include locking a locking mechanism, lock, locking device, etc. to hold the system, device, implant, etc. in the contracted configuration. The locking mechanism, lock, locking device, etc. can be the same and function and/or be operated in the same way as any of those described above. 
     It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove, as well as variations and modifications thereof that are not in the prior art, which would occur to persons skilled in the art upon reading the foregoing description. For example, a tool described for use with one of the implants described herein can optionally be used with another of the implants described herein, mutatis mutandis. Similarly, an adjustment mechanism or lock described for use in one of the implants described herein can optionally be used in another of the implants described herein, mutatis mutandis. Further, each of the methods, techniques, steps, etc. described herein can be performed on a living animal or on a non-living cadaver, cadaver heart, simulator, anthropomorphic ghost, etc.