Patent Publication Number: US-2022218480-A1

Title: Annuloplasty Implant System

Description:
FIELD OF THE INVENTION 
     This invention pertains in general to the field of cardiac valve repair. More particularly the invention relates to a system comprising an annuloplasty implant, such as an annuloplasty ring or helix, and a delivery device and a method of repairing a defective heart valve. 
     BACKGROUND OF THE INVENTION 
     Diseased mitral and tricuspid valves frequently need replacement or repair. The mitral and tricuspid valve leaflets or supporting chordae may degenerate and weaken or the annulus may dilate leading to valve leak. Mitral and tricuspid valve replacement and repair are frequently performed with aid of an annuloplasty ring, used to reduce the diameter of the annulus, or modify the geometry of the annulus in any other way, or aid as a generally supporting structure during the valve replacement or repair procedure. The annuloplasty ring is typically implanted around the annulus of the heart valve. 
     A problem with prior art annuloplasty implants is to achieve correct positioning at the heart valve and fixate the implant in the correct position. Suturing devices for annuloplasty implants have disadvantages that makes it difficult to suture in the correct position, thereby resulting insufficient suturing strength, and also in a very time-consuming procedure, which increases the risks for the patient. Furthermore, suturing devices are often not sufficiently compact for catheter based procedures. The use of clips for positioning annuloplasty implants is also associated with challenges, in particular when implanting helix rings that are to be positioned on either side of a heart valve. Insufficient fixation of such implant lead to traumatic effects since the fixation structure must ensure the correct position of the device over time. A further problem in the prior art is thus also to achieve a reliable fixation at the annulus of the heart valve. An annuloplasty implant is intended to function for years and years, so it is critical with long term stability in this regard. 
     The above problems may have dire consequences for the patient and the health care system. Patient risk is increased. 
     Hence, an improved annuloplasty implant would be advantageous and in particular allowing for avoiding more of the above mentioned problems and compromises, and in particular ensuring secure fixation of the annuloplasty implant, during the implantation phase, and for long-term functioning, in addition to a less complex procedure, and increased patient safety. A related method would also be advantageous. 
     SUMMARY OF THE INVENTION 
     Accordingly, examples of the present invention preferably seek to mitigate, alleviate or eliminate one or more deficiencies, disadvantages or issues in the art, such as the above-identified, singly or in any combination by providing a device according to the appended patent claims. 
     According to a first aspect a system is provided comprising an annuloplasty implant and a delivery device, the annuloplasty device comprises 
     first and second supports being adapted to be arranged as a coil in a coiled configuration around an axial direction, wherein the first and second supports are adapted to be arranged on opposite sides of native heart valve leaflets of a heart valve, wherein the delivery device comprises a locking structure to interlock with a correspondingly mating first locking structure of a delivery device connector of the annuloplasty implant, wherein the locking structure of the delivery device comprises a first locking side to lock rotational movement of the annuloplasty implant, when interlocked with the delivery device, around an axial direction (A) of the annuloplasty implant, and a second locking side to lock movement of the annuloplasty implant along said axial direction (A), when interlocked with the delivery device. 
     According to a second aspect an annuloplasty implant comprising first and second supports being adapted to be arranged as a coil in a coiled configuration around an axial direction, wherein the first and second supports are adapted to be arranged on opposite sides of native heart valve leaflets of a heart valve, a delivery device connector comprising a first locking structure to interlock with a correspondingly mating locking structure of a delivery device, wherein the first locking structure comprises a first locking surface to lock rotational movement of the annuloplasty implant, when interlocked with the delivery device, around an axial direction (A) of the annuloplasty implant, and a second locking surface to lock movement of the annuloplasty implant along said axial direction (A), when interlocked with the delivery device. 
     According to a third aspect a delivery device for an annuloplasty implant is provided, comprising a locking structure to interlock with a correspondingly mating first locking structure of a delivery device connector of the annuloplasty implant, wherein the locking structure of the delivery device comprises a first locking side to lock rotational movement of the annuloplasty implant, when interlocked with the delivery device, around an axial direction (A) of the annuloplasty implant, and a second locking side to lock movement of the annuloplasty implant along said axial direction (A), when interlocked with the delivery device. 
     According to a fourth aspect a method of repairing a defective heart valve is provided. The method comprises directing an implant delivery catheter to form a first curve of the implant delivery catheter around the heart valve at a first side of native heart valve leaflets thereof, forming a second curve of the delivery catheter around the heart valve on a second side of the heart valve leaflets opposite the first side, and ejecting an annuloplasty implant from the delivery catheter while retracting the delivery catheter such that the annuloplasty implant is arranged along the first and second curve on the first and second sides, releasing a locking structure of a delivery device being interlocked with a correspondingly mating first locking structure of a delivery device connector of the annuloplasty implant, the delivery device being arranged in the delivery catheter, whereby the locking structure is moved from an interlocked state, when interlocked with the mating first locking structure of the annuloplasty implant, to a released state upon which the locking structure of the delivery device deflects in a radial direction (R′) thereof, perpendicular to a longitudinal direction (L′) along which the delivery device extends with an elongated shape, whereby, in the released state, the locking structure of the delivery device is released from interlocking engagement with the mating first locking structure of the annuloplasty implant. 
     Further examples of the invention are defined in the dependent claims, wherein features for the second aspect are as for the first aspect mutatis mutandis. 
     Some examples of the disclosure provide for a facilitated positioning of an annuloplasty implant at a heart valve. 
     Some examples of the disclosure provide for a facilitated fixation of an annuloplasty implant at a heart valve. 
     Some examples of the disclosure provide for a less time-consuming fixation of an annuloplasty to a target site. 
     Some examples of the disclosure provide for securing long-term functioning and position of an annuloplasty implant. 
     Some examples of the disclosure provide for a reduced risk of damaging the anatomy of the heart such as the annulus or the valve leaflets. 
     Some examples of the disclosure provide for facilitated guidance of an annuloplasty implant to an annulus of a heart valve. 
     Some examples of the disclosure provide for a more secure implantation of an annuloplasty implant in narrow anatomies. 
     Some examples of the disclosure provide for avoiding interference of the annuloplasty implant with the chordae of the valve leaflets. 
     Some examples of the disclosure provide for facilitated interlocking and release of an annuloplasty implant with a delivery device. 
     It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other aspects, features and advantages of which embodiments of the invention are capable of will be apparent and elucidated from the following description of embodiments of the present invention, reference being made to the accompanying drawings, in which 
         FIGS. 1 a - b    are schematic illustrations of an annuloplasty implant according to examples of the disclosure; 
         FIG. 2  is a schematic illustration of an annuloplasty implant, when in an implanted state, according to an example; 
         FIGS. 3 a - b    are schematic illustrations of an annuloplasty implant, when in a stretched elongated configuration, according to examples of the disclosure; 
         FIG. 3 c    is a magnified view of sections of the annuloplasty implant in  FIG. 3 b   , according to an example; 
         FIGS. 3 d - f    are schematic illustrations of the cross-sections of the different sections of the annuloplasty implant in  FIGS. 3 b - c   , according to examples of the disclosure; 
         FIG. 4  is a schematic illustration of an annuloplasty implant according to an example; 
         FIGS. 5 a - b    are schematic illustration of an annuloplasty implant, having supports thereof separated by defined pitch distances, according to examples of the disclosure; 
         FIG. 6 a    is a schematic illustration of an arrangement of a delivery device in a method according to one example, where the delivery device has been initially advanced to the ventricle to form a first curve on a ventricular side of the heart valve and a second curve on an atrial side thereof; 
         FIG. 6 b    is a schematic illustration of an arrangement of a delivery device in a method according to one example, where an annuloplasty implant has been ejected on the atrial and ventricular side while retracting the delivery device; 
         FIG. 6 c    is a schematic illustration of an arrangement of a delivery device in a method according to one example, where the delivery device has been further retracted and the annuloplasty implant contacts the heart valve on the atrial and ventricular side thereof; 
         FIG. 7 a    is a schematic illustration of an arrangement of a delivery device in a method according to one example, where the delivery device has been initially advanced to the atrium to form a first curve on a ventricular side of the heart valve; 
         FIG. 7 b    is a schematic illustration of an arrangement of a delivery device in a method according to one example, where the delivery device forms a second curve on an atrial side of the heart valve; 
         FIG. 7 c    is a schematic illustration of an arrangement of a delivery device in a method according to one example, where an annuloplasty implant has been ejected on the ventricular side while retracting the delivery device; 
         FIG. 7 d    is a schematic illustration of an arrangement of a delivery device in a method according to one example, where the delivery device has been further retracted and the annuloplasty implant contacts the heart valve on the atrial and ventricular side thereof; 
         FIGS. 8 a - b    are schematic illustrations of an annuloplasty implant, in a cross-sectional view ( 8   a ), and in a side view ( 8   b ), respectively, according to examples of the disclosure; 
         FIG. 8 c    is a magnified view of a retention unit in  FIGS. 8 a   - b;    
         FIGS. 9 a - b    are schematic illustrations of an annuloplasty implant, in a cross-sectional view ( 9   a ), and in a side view ( 9   b ), respectively, according to examples of the disclosure; 
         FIGS. 10 a - b    are schematic illustrations of an annuloplasty implant, in a cross-sectional view ( 10   a ), and in a side view ( 10   b ), respectively, according to examples of the disclosure; 
         FIGS. 11 a - b    are schematic illustrations of an annuloplasty implant, in a cross-sectional view ( 11   a ), and in a side view ( 11   b ), respectively, according to examples of the disclosure; 
         FIG. 12 a    is a flow chart of a method of repairing a defective heart valve according to one example; 
         FIG. 12 b    is another flow chart of a method of repairing a defective heart valve according to one example; 
         FIG. 13 a    is a schematic illustration of an annuloplasty implant and a delivery device, in a side view, where the delivery device releases the annuloplasty implant; 
         FIG. 13 b    is a schematic illustration of an annuloplasty implant and a delivery device, in a perspective view, where the delivery device is interlocked with the annuloplasty implant; and 
         FIG. 13 c    is a schematic illustration in a further detailed perspective view of an annuloplasty implant interlocked with a delivery device. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Specific embodiments of the invention will now be described with reference to the accompanying drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. The terminology used in the detailed description of the embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. In the drawings, like numbers refer to like elements. 
     The following description focuses on an embodiment of the present invention applicable to cardiac valve implants such as annuloplasty rings. However, it will be appreciated that the invention is not limited to this application but may be applied to many other annuloplasty implants and cardiac valve implants including for example replacement valves, and other medical implantable devices. 
       FIGS. 1 a - b    are schematic illustration of an annuloplasty implant  100 ,  1000 , comprising first  101  and second  102  supports being adapted to be arranged as a coil in a coiled configuration around an axial direction  103 . The first and second supports  101 ,  102 , are adapted to be arranged on opposite sides of native heart valve leaflets  104  of a heart valve, as illustrated in  FIG. 2 . As shown in  FIG. 2 , the first support  101  may be arranged on an atrial side of the valve, and the second support  102  may be arranged on a ventricular side. The first and second supports  101 ,  102 , are connected to form a coil- or helix shaped ring. The coil extends through the valve opening (dashed line) at a commissure thereof. In the examples of  FIGS. 1-2 , the second support  102  forms a complete loop, whereas the first support  101  has a reduced length along its periphery, as will be described further below. The implant  100 ,  1000 , may comprise a shape-memory material, so that the implant  100 ,  1000 , assumes the coiled configuration after having been ejected from a delivery catheter. While in the delivery catheter the implant  100 ,  1000 , may be stretched in an elongated shape, i.e. as illustrated in  FIGS. 3 a - b   . Alternatively, the implant  100 ,  1000 , may be arranged in the coiled configuration when being delivered to the target site, in which case it may be implanted at the target site for example by incision between the ribs or by opening the chest. The present disclosure, and the associated advantages described for the various examples, applies to both such variants of the implant  100 ,  1000 . 
     The annuloplasty implant  100 ,  1000 , comprises a delivery device connector  501  comprising a first locking structure  502  to interlock with a correspondingly mating locking structure  503  of a delivery device  301 , as schematically illustrated in  FIGS. 13 a - b   . The first locking structure  502  may comprise a first locking surface  502   a  to lock rotational movement of the annuloplasty implant  100 ,  1000 , when interlocked with the delivery device  301 , around an axial direction (A) of the annuloplasty implant  100 ,  1000 . The first locking structure  502  may further comprise a second locking surface  502   b  to lock movement of the annuloplasty implant  100 ,  1000 , along the axial direction (A), when interlocked with the delivery device  301 . Hence, both rotational movement around axis (A), and longitudinal movement along axis (A), may be effectively controlled by having such first and second locking surfaces  502   a ,  502   b . This allows for a facilitated delivery and control of the position of the annuloplasty implant  100 ,  1000 . The first locking surface  502   a  may have a normal perpendicular to the axial direction (A), and the second locking surface  502   b  may have a normal parallel to the axial direction (A).  FIG. 13 b    show one example of such locking structure  502 . 
     The first locking structure  502  may be substantially T-shaped to interlock with a correspondingly mating T-shaped locking structure  503  of a delivery device  301 . The T-shaped first locking structure  502  may comprise a distal stem  506 ′ being connected to a proximal tip  507 ′ of increased width relative the distal stem  506 , as schematically shown in the example of  FIG. 13 c   . The proximal tip  507 ′ may be configured to interlock with a proximal stem  506  of the delivery device  301 . As further shown in the example of  FIG. 13 c   , the distal stem  506 ′ may be configured to interlock with a distal tip  507  of the delivery device  301 . A robust and effective first interlocking structure  502  for interlocking with a delivery device  301  is thus provided. The annuloplasty implant  100  may comprise two oppositely arranged T-shaped locking structures  502 , although  FIG. 13 c    only shows one locking structure for a clearer illustration. Having two such oppositely arranged locking structures  502 , arranged to interlock with correspondingly mating locking structures  503  of a delivery device  100 , also being oppositely arranged as described further below, provides for a particularly robust and effective connection interface between the annuloplasty implant  100 ,  1000 , and a delivery device  301 . 
     The T-shaped first locking structure  502  may comprise a proximal recess  505  to receive a protrusion  504  of the delivery device  301 . This provides for a self-centering positioning of the annuloplasty implant  100 ,  1000 , relative the delivery device  301  when the latter engages the first locking structure  502 . The proximal recess  505  may be tapering in a direction from the delivery device  301  towards the first and/or second support rings  101 ,  102 , as shown in the example of  FIG. 13 c   . This provides for a protrusion  504  of the delivery device  301  to easier slide into the correct position in the recess  505 . 
     A system  500  comprising an annuloplasty implant  100 ,  1000 , and a delivery device  301  is provided. The annuloplasty implant  100 ,  1000 , may comprise an annuloplasty implant  100 ,  1000 , as described in relation to  FIGS. 1-11 . The annuloplasty implant  1000  in  FIG. 1 b    comprises first  101  and second  102  supports being adapted to be arranged as a coil in a coiled configuration around an axial direction  103 , where the first and second supports  101 ,  102 , are adapted to be arranged on opposite sides of native heart valve leaflets  104  of a heart valve. 
     The delivery device  301  comprises a locking structure  503  to interlock with a correspondingly mating first locking structure  502  of a delivery device connector  501  of the annuloplasty implant  100 ,  1000 . The locking structure  503  of the delivery device  301  comprises a first locking side  503   a  to lock rotational movement of the annuloplasty implant  100 ,  1000 , when interlocked with the delivery device  301 , around an axial direction (A) of the annuloplasty implant  100 ,  1000 . The locking structure  503  of the delivery device  301  comprises a second locking side  503   b  to lock movement of the annuloplasty implant  100 ,  1000 , along the axial direction (A), when interlocked with the delivery device  301 . A system  500  with an effective and robust connection mechanism between the delivery device  301  and the annuloplasty implant  100 ,  1000 , is provided. 
     A delivery device  301  is provided, comprising a locking structure  503  to interlock with a correspondingly mating first locking structure  502  of a delivery device connector  501  of the annuloplasty implant  100 ,  1000 . The locking structure  503  of the delivery device  301  comprises a first locking side  503   a  to lock rotational movement of the annuloplasty implant  100 ,  1000 , when interlocked with the delivery device  301 , around an axial direction (A) of the annuloplasty implant  100 ,  1000 . The locking structure  503  of the delivery device  301  comprises a second locking side  503   b  to lock movement of the annuloplasty implant  100 ,  1000 , along the axial direction (A) when interlocked with the delivery device  301 . A delivery device  301  providing for an effective control and positioning of an annuloplasty implant  100 ,  1000 , is thus provided. 
     The locking structure  503  may be movable from an interlocked state, when interlocked with the mating first locking structure  502  of the annuloplasty implant  100 ,  1000 , as shown in  FIG. 13 b   , to a released state as shown in  FIG. 13 a    upon which the locking structure  503  of the delivery device  301  deflects in a radial direction (R′) thereof, perpendicular to a longitudinal direction (L′) along which the delivery device  301  extends with an elongated shape. Hence, in the released state, the locking structure  503  of the delivery device  301  is released from interlocking engagement with the mating first locking structure  502  of the annuloplasty implant  100 ,  1000 . This provides for an effective and reliable interlocking and releasing of the annuloplasty implant  100 ,  1000 . 
     The delivery device  301  may comprise a sheath  505  being movable along the longitudinal direction (L′), as illustrated in  FIG. 13 a   . The locking structure  503  may comprises a shape memory material being biased to deflect in the radial direction (R′) to assume the aforementioned released state as illustrated in  FIG. 13 a   . The sheath  505  is movable from an extended state in which the sheath  505  forces the locking structure to the interlocked state as shown in  FIG. 13 b    (sheath  505  is omitted in  FIG. 13 b    for a clearer illustration), to a retracted state as shown in  FIG. 13 a   , in which the sheath  505  releases the restraining force on the locking structure  503  so that the locking structure  503  deflects in the radial direction (R′) for releasing the annuloplasty implant  100 ,  1000 . This provides for an effective and reliable control of the interlocking and releasing of the annuloplasty implant  100 ,  1000 . 
     The locking structure  503  may comprise two oppositely arranged locking structures  503 ,  503 ′, in the radial direction (R′). Thus, in said released state, the oppositely arranged locking structures  503 ,  503 ′, may deflect in opposite radial directions, as schematically shown in the example of  FIG. 13   a.    
     The oppositely arranged locking structures  503 ,  503 ′, may be symmetric in shape. This allows for interlocking with the annuloplasty implant  100 ,  1000 , when having the delivery device  301  in two different directions for a facilitated control. 
     The delivery device  301  may comprise a protrusion and/or recess  504  arranged between the oppositely arranged locking structures  503 ,  503 ′, along the radial direction (R′), and extending in the longitudinal direction (L′) to interlock with a correspondingly mating protrusion and/or recess  505  of the annuloplasty implant  100 ,  1000 . This provides for a facilitated centering of the annuloplasty implant  100 ,  1000 , relative the delivery device  301  as elucidated above. 
     The delivery device  301  may comprise a protrusion  504  as illustrated in  FIG. 13 b   , and the protrusion  504  may taper towards the annuloplasty implant  100 ,  1000 , along the longitudinal direction (L′). Facilitated centering and interlocking of the annuloplasty implant  100 ,  1000 , may thus be provided as described above. 
     The locking structure  503  may be substantially T-shaped with a proximal stem  506  being connected to a distal tip  507  of increased width relative the stem  506 , as illustrated in  FIG. 13 c   . The distal tip  507  may be configured to interlock with a distal stem  506 ′ of the annuloplasty implant  100 ,  1000 . Likewise, the proximal stem  506  may be configured to interlock with a proximal tip  507 ′ of the annuloplasty implant  100 ,  1000 . 
     The annuloplasty implant  100  may comprise retention units  105 ,  105 ′, as exemplified in  FIG. 1 a   , where the first support  101  comprises first retention units  105  arranged along at least a first retention portion  107  thereof. The first retention units  105  may be fixed in relation to an outer surface  106  of the first support  101 . The second support  102  may comprise second retention units  105 ′ arranged along at least a second retention portion  107 ′ thereof. The second retention units  105 ′ may be fixed in relation to an outer surface  106 ′ of the second support. The retention units  105 ,  105 ′, are illustrated in the perspective views of  FIGS. 1 a    and  2 , and in the schematic side views of  FIGS. 3 a - c    of the implant  100  when stretched in an elongated shape, as well in cross-sectional views of  FIGS. 3 e - f   . As seen in  FIGS. 1 a    and  2 , the first and second retention portions  107 ,  107 ′, may be curved in the coiled configuration. Hence, the retention units  105 ,  105 ′, may be arranged to extend along the curved shape of the coil- or helix shaped implant  100 . The first retention portion  107  may be configured to follow the curvature of the annulus of the heart valve, such as the mitral- or tricuspid valve. The second retention portion  107 ′ may be configured to follow the shape of the valve from the ventricular side. The first and second retention units  105 ,  105 ′, may extend from respective first and second retention portions  107 ,  107 ′, to produce a retention force, in use, at both of said opposite sides of the native heart valve leaflets. Having retention units  105 ,  105 ′, at both sides of the valve provides for increasing the retention force and the strength by which the annuloplasty implant  100  is fixated at the valve. The first retention units  105  may pierce and anchor into the tissue at a first side of the valve independently of the second retention units  105 ′ which may pierce and anchor into the tissue at a second side, opposite the first side. This provides for having the first support  101  repositionable relative the second support  102  since any interlocking therebetween can be dispensed with. This provides for a facilitated optimization of the position of the first and second supports  101 ,  102 , at opposite sides of the heart valve. The retention units  105 ,  105 ′, may engage the tissue from both of the mentioned sides, creating a strong retention force in the radial direction, i.e. perpendicular to the axial direction  103 . The first and second supports  101 ,  102 , pinch the tissue from both sides of the valve, so that the retention units  105 ,  105 ′, a forced into the tissue. The retention units  105 ,  105 ′, provides for shaping the annulus as desired even with a reduced pinching force, since the retention units  105 ,  105 ′, provides for fixating the shape of the annulus in the radial direction because of the mentioned retention force. This provides for a more reliable implantation at the heart valve, both in the short term and in the long term. In the example of having the first and second retention units  105 ,  105 ′, fixed in relation to a respective outer surface  106 ,  106 ′, a robust, less complex and more readily implementable fixation mechanism can be provided, since there is no need for e.g. active retention mechanisms that are activated to move relative the outer surface  106 ,  106 . The aforementioned fixed position in relation to the respective outer surface  106 ,  106 ′, may be construed as having the retention units  105 ,  105 ′, attached to the first and second supports  101 ,  102 , at a pre-defined position during manufacturing, or integrated with the first and second supports  101 ,  102 , at a pre-defined position during manufacturing. As illustrated in e.g.  FIG. 1 , a plurality of retention units  105 ,  105 ′, may be provided on the respective first and second supports  101 ,  102 . Each individual retention unit  105 ,  105 ′ may engage or pierce into the tissue with a short distance, for a minimum amount of injury to the tissue. The sum of the retention force and friction created from all the retention units  105 ,  105 ′, still provides for a strong fixation into the tissue. The scar healing will be quick since each individual retention unit  105 ,  105 ′, as relatively small dimensions. This provides for a non-traumatic and still secure fixation of the implant  100 . Hence, the retention units  105 ,  105 ′, provides for tissue fixation at multiple points across the implant  100  instead of a few, e.g. 5 or 7 isolated stiches, resulting in reduced forces per fixation point, and no need for bulky stitching device or knotting device. There is further no risk of coronary artery occlusion or coronary sinus perforation. Hence, the implant  100  provides for ease of operation, and a less time consuming procedure than stitching. 
     In another example, schematically illustrated in  FIG. 1 b    the annuloplasty implant  1000  comprises first and second supports  101 ,  102 , which pinches the valve tissue therebetween with a force sufficiently strong to anchor the annuloplasty implant  1000  at the heart valve. 
     Turning again to  FIG. 1 a   , the first retention units  105  may extend from the first retention portion  107  in a direction towards the second support  102 . This allows the first retention units  105  to be securely fixed in to the tissue in the direction where the pinching force may be strongest. 
     Likewise, the second retention units  105 ′ may extend from the second retention portion  107 ′ in a direction towards the first support  101 , so that the second retention units  105 ′ may engage or pierce into the tissue effectively. 
     The first and second retention units  105 ,  105 ′, may extend in opposite directions along the axial direction  103 , as illustrated in the example in e.g.  FIG. 1 a   . I.e. the first and second retention units  105 ,  105 ′, may extend from respective retention portions  107 ,  107 ′, towards each other, to clamp the tissue therebetween. It is conceivable however that the retention units  105 ,  105 ′, may extend in different directions. The first retention units  105  may for example extend with an angle in a radially outward direction to engage tissue in a direction towards a tissue wall radially outside the annulus. 
     The first and second supports  101 ,  102 , may be separated with a first pitch distance (p 1 ) in the axial direction  103 , in the coiled configuration, as illustrated in  FIG. 5 a   . Features described for the annuloplasty implant  100  applies also to the annuloplasty implant  100 . The first and/or second support may comprise a shape-memory material configured to assume a contracted state having a second pitch distance (p 2 ) in the axial direction  103  being shorter than the first pitch distance (p 1 ), as illustrated in  FIG. 5 b   . Thus, the first and second supports  101 ,  102 , may contract along the axial direction due to movement of the shape-memory material. This provides for increasing the force by which the annuloplasty implant  100 ,  1000 , is fixed at the annuls. The retention units  105 ,  105 ′, of annuloplasty implant  100  may engage the tissue with an increased force from both sides of the valve. The annuloplasty implant  100 ,  1000 , may be arranged at the valve when assuming the first pitch distance (p 1 ). The shape-memory material may then be activated so that the contracted state is assumed, with the reduced distance (p 2 ) between the supports  101 ,  102 , and the retention portions  107 ,  107 ′, thereof. 
     The shape-memory material may be configured to assume the contracted state in response to an activation temperature. For example, the temperature may be increased to an activation temperature, so that the annuloplasty implant assumes the contracted state with a reduced pitch distance (p 2 ). It is conceivable that the implant  100 ,  1000 , may be kept at a defined temperature while arranged in a delivery catheter. Subsequently, when the implant  100 ,  1000 , is exposed to the warm tissue, when being ejected from the delivery catheter, the activation temperature may be reached, so that the first and second supports  101 ,  102  contracts towards each other. Retention units  105 ,  105 ′, of annuloplasty implant  100  can be forced into the tissue. A delivery catheter  301  is illustrated in  FIGS. 6 a - c , 7 a - c   , which will be described further below. 
     The implant  100 ,  1000 , may comprise a shape memory material, such as NiTiNol, or another suitable biocompatible alloy that can be heat-set in defined shapes, in a heat treatment procedure. The shape-memory material may comprise a material having more than one phase, so that the shape of the supports  101 ,  102 , may be actively varied as described above. The shape memory material can be conceived as any material that is able to change shape as desired, in response to outside interaction, for example with an energy source, such as providing heat and/or electromagnetic energy, that can be transferred to the implant to change its shape. It is also conceivable that the shape of the implant can be affected by direct mechanical manipulation of the curvature of the ring-shape of the implant  100 ,  1000 , e.g. by transferring a force or torque to the implant  100 ,  1000 , via a delivery device. Via the various mentioned shape-affecting procedures the implant  100 ,  1000 , may assume an elongated delivery configuration for advancement in a catheter, an initial shape when positioned in a coiled configuration along the annulus of the valve, and also an activated shape such as the contracted state described above for enhancing the strength of the fixation at an annulus of the heart valve. 
     The first and second supports  101 ,  102 , may be configured to engage with a restraining unit at a separation at the first pitch distance (p 1 ) and to assume the contracted state upon removal of the restraining unit. This provides for facilitating the positioning of the implant  100 ,  1000 , at both sides of the valve, since the pitch distance (p 1 ) may first be increased to avoid undesired friction with the tissue or entanglement with parts of the anatomy. The restraining unit may comprise a delivery catheter  301 , which may be positioned around the annulus as described further below with reference to  FIGS. 6 a - c , 7 a - c   , while the first and second supports  101 ,  102 , assumes the curvature of the delivery catheter  301  with a first pitch distance (p 1 ). When the delivery catheter  301  is retracted, exposing the annuloplasty implant  100 , the first and second supports  101 ,  102 , may contract to the reduced pitch distance (p 2 ). It is conceivable however that the implant  100 ,  1000 , may engage with various other restraining units, such as biodegradable elements that allows the implant  100 ,  1000 , to assume its contracted shape after being biodegraded or in other ways removed. 
     In one example, at least part of the first retention units  105  may be displaced in a direction along an annular periphery  114  of the coil in relation to at least part of the second retention units  105 ′. A line  116  extending from a first retention unit  105 , parallel with the axial direction  103 , may thereby intersect the annular periphery  114  of the second support  102  at a position between two second retention units  105 ′.  FIG. 4  illustrates the first and second retention units  105 ,  105 ′, being displaced in relation to each other, so that the first retention units  105  may move towards a position between the second retention units  105 ′ (as illustrated by dashed line  116 ). This may provide for further increasing the retention strength, while minimizing the risk that the retention units  105 ,  105 ′, pierce completely through the valve tissue. This risk for complications is thereby reduced. 
     At least part of the first and second retention units  105 ,  105 ′, may comprise a shape that tapers in a direction from the respective first and second retention portions  107 ,  107 ′, as illustrated in the examples of e.g.  FIGS. 1, 3   c - f . This may provide for facilitating pushing and/or piercing of the retention units  105 ,  105 ′, into the tissue, while scars are kept at a minimum. The retention units  105 ,  105 ′, may comprise other structures configured to engage the tissue, such as barbs, needles etc. 
     The first support  101  may be adapted to be arranged on an atrial side of the heart valve, and the second support  102  may be adapted to be arranged on a ventricular side of the heart valve. The first support  101  may comprise a first posterior bow  108  and the second support  102  comprises a second posterior bow  108 ′. The first and second posterior bows  108 ,  108 ′, may be adapted to conform to a posterior aspect of the heart valve. The first and second retention units  105 ,  105 , may be arranged on respective first and second posterior bows  108 ,  108 ′, as illustrated in  FIGS. 1-2 . This provides for avoiding piercing the tissue at an anterior side  109  of the annuloplasty implant, which can be associated with a greater risk of complications. 
     Hence, the first and second posterior bows  108 ,  108 ′, may be separated by an intermediate anterior portion  109 . The first and second retention units  105 ,  105 ′, may be arranged with an off-set distance  110  from the anterior portion  109  towards respective first and second posterior bows  108 ,  108 ′, so that the anterior portion  109  may comprise a smooth surface free from retention units  105 ,  105 ′.  FIGS. 3 a - c    also show illustrations of the anterior portion  109  positioned between the first and second retention portions  107 ,  107 ′, when the implant  100  is in the elongated stretched state. The off-set distance  110  may be varied to optimize the annuloplasty implant to the particular anatomy while ensuring that there is no risk of piercing the tissue at the anterior side of the valve. 
     The first retention units  105  may be formed from the material of the first support  101 . This may provide for particularly robust and strong first retention units  105 . Similarly, the second retention units  105 ′ may be formed from the material of the second support  102 . The first and second supports  101 ,  102 , may be integrated and formed from a continuous piece of material. Hence, the first and second retention units  105 ,  105 ′, may also be formed from such material. The retention units  105 ,  105 ′, may be cut from the material of the first and second support  101 ,  102 .  FIG. 3 b    shows an example where the retention units  105 ,  105 ′, are cut from the material of the first and second supports  101 ,  102 .  FIG. 3 c    is a magnified view of  FIG. 3 b    showing an example of different sections of the implant  100 . As mentioned, the first support  101  may have the retention units  105  extending in a first direction, and the second support  102  may have the retention units  105 ′ extending in an opposite direction. An intermediate portion  109 , without retention units  105 ,  105 ′, may be positioned therebetween.  FIGS. 3 e - f    show examples of the cross-sections of the implant  100  at the mentioned sections illustrated in  FIG. 3 c   , in the case the retention units  105 ,  105 ′, are formed from the material of the implant  100 . I.e.  FIG. 3 d    shows a cross-section of the first support  101 , where material has been removed (indicated by arrow  117  in the figure) from an initially substantially circular support to create tapered retention units  105 .  FIG. 3 e    corresponds to the cross-section of the intermediate portion  109 , and  FIG. 3 f    shows the cross-section of the second support  102  where material has been cut away to form retention units  105 ′ in the opposite direction. The retention units  105 ,  105 ′, may be cut to form various shapes for optimizing the gripping force into the tissue. The retention units  105 ,  105 ′, may be formed by different cutting techniques such as milling or laser cutting techniques. It is also conceivable that the retention units  105 ,  105 ′, are fixed or integrated onto the respective support  101 ,  102 , by other methods, or by being formed from other materials. 
     The support  101 ,  102 , of the annuloplasty implant  100 ,  1000 , may be formed from a solid rod or other solid elongated structure, having various cross-sections, such as circular, elliptic, rhombic, triangular, rectangular etc. The support  101 ,  102 , may be formed from a hollow tube, or other hollow structures with the mentioned cross-sections. The support  101 ,  102 , may be formed from a sandwiched laminate material, comprising several layers of different materials, or different layers of the same material. The support  101 ,  102 , may be formed from a stent or a stent-like structure, and/or a braided material. The support  101 ,  102 , may be formed from a braid of different materials braided together, or from a braid of the same material. As mentioned, the support  101 ,  102 , may be formed from NiTinol, or another suitable bio-compatible material. The surfaces of the first and second supports  101 ,  102 , may be provided with other materials and/or treated with different materials and/or structured to enhance resistance to breaking in case the material is repeatedly bent. 
     The first and second supports  101 ,  102 , may have respective free ends  111 ,  111 ′, configured to be arranged on opposite sides of the native heart valve leaflets, in the coiled configuration, as illustrated in e.g.  FIGS. 1-2 . The two free ends  111 ,  111 ′, may be displaced from each other with a peripheral off-set distance  112  extending in a coil plane  113 , as schematically illustrated in  FIG. 4 . The coil plane  113  is substantially parallel to an annular periphery  114  of the coil and perpendicular to the axial direction  103 . The coil plane  113  accordingly corresponds to the plane spanned by the annular periphery  1114  of the implant  100  when assuming the coiled configuration. The peripheral off-set distance  112  between the two free ends  111 ,  111 ′, thus extends substantially perpendicular to the central axis  103 . This means that, when the implant  100 ,  1000 , is positioned in the implanted state, around the annulus of the heart valve, the two free ends will be separated along the plane of the valve. By having such off-set  112  in the plane of the valve, the resulting reduced length of the first or second support member  101 ,  102 , will allow for reducing the number of retention units  105 ,  105 ′, required to securely fixate the implant  100 ,  1000 , at the valve, while at the same time providing for a sufficient overlap of the first and second support member  101 ,  102 , on the opposites sides of the valve to attain a sufficiently strong pinching effect therebetween to fixate the annulus in a modified shape. In situations, placing retention units  105 ,  105 ′, on the anterior side may be associated with high risk, as discussed above. This can therefore be avoided, by having the off-set  112  as specified. Furthermore, the interference of the implant  100 ,  1000 , with the movements of the valve will be minimized. Fastening of the implant  100 ,  1000 , on the atrial side can thus be accomplished by fixation of the posterior bow  108 , and there will be no interference on the atrial side with the movement of the valve, due to the off-set distance  112  reducing the circle sector of the first support  101 . 
     The off-set distance  112  may correspond to a determined circle sector  115  of the annular periphery  114  by which the two free ends  111 ,  111 ′, are separated. Hence, the determined circle sector  115  may overlap with the anterior portion  109  in the coiled configuration. The length of the circle sector  115  and the associated distance by which the two free ends  111 ,  111 ′, are separated may be varied to accommodate various applications and procedures, and be tailored to various anatomies. It is thus possible to provide a highly compliant implant  100 ,  1000 , with a minimum of interference with the natural movements of the heart, and which can be secured more easily via retention units  105 ,  105 ′. 
     The first retention units  105  and/or the second retention units  105 ′ may extend in a longitudinal direction (L), and comprise a distal surface  118  forming a tapering shape towards a piercing edge  119 , as schematically illustrated in the example of  FIG. 8 c   . This provides for robust retention units  105 ,  105 ′, allowing for effective grip into the surrounding tissue. The distal surface  118  may extend across the full width (w) of the retention unit  105 ,  105 ′, so that the piercing edge  119  is positioned at the periphery of the width (w) as shown in the example of  FIG. 8 c   . Alternatively, the retention units  105 ,  105 ′, may be tapered towards a central piercing edge  119  as shown in the example of  FIGS. 10 a - b   . In this case, the distal surface  118  may comprise two oppositely chamfered surfaces being joined along the centrally located piercing edge  119 . Alternatively, the retention units  105 ,  105 ′, may comprise a conically tapering surface that narrows towards a centrally located piercing edge or tip  119  like a needle. Turning again to  FIGS. 8 a - c   , the distal surface  109  extends in a plane having a normal axis (N) forming an acute angle (a) with the longitudinal direction (L). This provides for a robust retention unit  105 ,  105 ′, while facilitating manufacturing thereof. 
     The first and second supports  101 ,  102 , extend with an elongated shape along an axial direction (A), as schematically illustrated in e.g.  FIG. 8 b   . The first and second supports  101 ,  102 , are shown in the elongated stretched state, as in  FIG. 3 a   , for a clearer presentation. The normal axis (N) may be substantially parallel with a plane spanned by the axial direction (A) and the longitudinal direction (L), as schematically illustrated in  FIGS. 8 b - c   . This allows for arranging the piercing edge  119  so it extends transverse to the axial direction (A), and also transverse to a surrounding delivery catheter, when arranged therein, which may be advantageous in some applications when the implant  100  is delivered to the annulus. Any risk of wear or damage to the surrounding catheter may be reduced in such case. 
     The axial direction (A) is perpendicular to a radial direction (R) of the first and second supports  101 ,  102 , as shown in  FIGS. 9 a - b   . In this example, the normal axis (N) is substantially parallel with a plane spanned by the radial direction (R) and the longitudinal direction (L). This may provide for an enhanced grip in the surrounding tissue when the implant  100  is in the coiled shape around the annulus of the heart valve. The direction along which the piercing edge  119  extends may thus be aligned with the axial direction (A), which provides for an improved retention force into the tissue, as the tissue strive to move in a direction perpendicular to the axial direction (A) as the heart is beating, and when the implant  100  is in the coiled shape. The implant  100  may be coiled so that the radial direction (R) is directed from the center of the heart valve towards the annulus. In other situations, the implant  100  may be coiled so that the radial direction (R) is directed from the annulus to the center of the heart valve. As shown in the example of  FIG. 9 a   , the shape of the second retention units  105 ′ may be symmetric with the first retention units  105  with respect to the radial direction (R). It should be understood however that in some applications it may be advantageous to have respective vector components of the normal axis (N) along the radial direction (R) of the first and second retention units  105 ,  105 ′, oppositely directed with respect to the radial direction (R). 
     The longitudinal direction (L) may extend with an angle (v), such as an acute angle (v), relative a normal axis (N′) of a surface  120  of the first and/or second supports  101 ,  102 , to which the first retention units  105  and/or the second retention units  105 ′ are fixed, as schematically illustrated in  FIG. 11 a   . Although the angle v is shown in the plane defined by the normal axis (N′) and the radial direction (R) it should be understood that the retention units  105  may be angled in the plane defined by the normal axis (N′) and the axial direction (A), i.e. having an angle v in the aforementioned plane. Having the retention units  105  angled in this direction may facilitate introduction of the implant  100  in a delivery catheter. Further, having angled retention units  105 ,  105 ′, may provide for a further improved anchoring effect into the tissue and reduce the risk of dislocation between the retention units  105 ,  105 ′, and the annulus. As in the previously described example, the implant  100  may be coiled so that the radial direction (R) is directed from the center of the heart valve towards the annulus. This may provide for further reducing the risk of having the annulus tissue to move relative the implant  100  in the radial direction (R) as the heart is beating. In other situations, the implant  100  may be coiled so that the radial direction (R) is directed from the annulus to the center of the heart valve. As shown in the example of  FIG. 11 a   , the shape of the second retention units  105 ′ may be symmetric with the first retention units  105  with respect to an axis of symmetry around the radial direction (R). It should be understood however that in some applications it may be advantageous to have respective vector components of the normal axis (N) along the radial direction (R) of the first and second retention units  105 ,  105 ′, oppositely directed with respect to the radial direction (R). 
     The first retention units  105  and/or the second retention units  105 ′ may be movable relative a normal axis (N′) of surface  120  of the first and/or second supports  101 ,  102 , to which the first retention units  105  and/or the second retention units  105 ′ are fixed. The first retention units  105  and/or the second retention units  105 ′ may be movable by being flexible. This provides for e.g. delivering the implant  100  in a more compact cross-sectional shape through a catheter, having the retention units  105 ,  105 ′, deflected with a greater angle relative the normal axis (N′). Then, as the implant  100  is ejected from the catheter, the angle may be reduced so that the retention units  105 ,  105 ′, extend a greater distance from the surface  120 , for facilitated piercing into the tissue. The retention units  105 ,  105 ′, may deflect with an angle (v) towards the radial direction (R) as shown in  FIG. 11 a   , or with an angle (a) towards the axial direction (A) as shown in  FIG. 8 b - c   . The first retention units  105  and/or the second retention units  105 ′ may be movable by being formed by a shape memory material which changes shape over time, e.g. when being heated to an activation temperature. 
     The height (h) of the retention units  105 ,  105 ′, may be in the range 0.5-2 mm, which may provide for a particularly advantageous grip into the tissue, while at the same time allowing for a facilitated delivery of the implant  100  from a delivery catheter to the annulus of the heart valve. The first and second retention units  105 ,  105 ′, may be evenly separated along the length of the respective first and second supports  101 ,  102 . The spacing between adjacent retention units  105 ,  105 ′, may be in the range 0.5-2 mm. The spacing between adjacent retention units  105 ,  105 ′, may also be in the range 1-1.5 mm, which may provide for a particularly advantageous anchoring into the tissue. 
     A method  200  of repairing a defective heart valve is disclosed. The method  200  is schematically illustrated in  FIG. 12 a   , in conjunction with  FIGS. 6 a - c    and  FIGS. 7 a - d   . The order in which the steps are described should not be construed as limiting, and it is conceivable that the order of the steps may be varied depending on the particular procedure. The method  200  comprises directing  201  an implant delivery catheter  301 ′ to form  202  a first curve  302  of the implant delivery catheter  301 ′ around the heart valve at a first side of native heart valve leaflets thereof.  FIGS. 6 a - c    illustrate an example where the delivery catheter  301 ′ is first advanced to the ventricular side of the heart, and  FIGS. 7 a - c    illustrate an example where the delivery catheter  301 ′ is initially advanced to the atrial side of the heart. Regardless, the method  200  further comprises forming  203  a second curve  303  of the delivery catheter  301 ′ around the heart valve on a second side of the heart valve leaflets, opposite the first side. The described positioning of the delivery catheter  301 ′ may be preceded by the positioning of a guide wire (not shown) along corresponding first and second curves  302 ,  303 . Thus, the delivery catheter  301 ′ may then be advanced over the guide wire, to assume the first and second curves  302 ,  303 , around the valve on either side of the leaflets thereof. The method  200  comprises ejecting  204  an annuloplasty implant  100 ,  1000 , from the delivery catheter  301 ′ while retracting  205  the delivery catheter  301 ′ such that the annuloplasty implant  100 ,  1000 , is arranged along the first and second curve  302 ,  303 , on the first and second sides. The method  200  comprises releasing  205 ′ a locking structure  503  of a delivery device  301  (see e.g.  FIGS. 13 a - b   ) being interlocked with a correspondingly mating first locking structure  502  of a delivery device connector  501  of the annuloplasty implant  100 ,  1000 . The delivery device  301  may be arranged in the delivery catheter  301 ′. The locking structure  503  is moved from an interlocked state, when interlocked with the mating first locking structure  502  of the annuloplasty implant  100 ,  1000 , to a released state upon which the locking structure  503  of the delivery device  301  deflects in a radial direction (R′) thereof, perpendicular to a longitudinal direction (L′) along which the delivery device  301  extends with an elongated shape. In the released state, the locking structure  503  of the delivery device  301  is released from interlocking engagement with the mating first locking structure  502  of the annuloplasty implant  100 ,  1000 . A particularly efficient and robust release of the annuloplasty implant  100 ,  1000 , may thus be provided. 
       FIG. 12 b    illustrates a further flow chart of a method  200  of repairing a defective heart valve. The order in which the steps of the method  200  are illustrated should not be construed as limiting and it is conceivable that the order in which the steps of the method  200  is carried out may be varied. 
     In one example, when having retention units  105 ,  105 ′, arranged on the annuloplasty implant  100 , the retention units  105 ,  105 ′, may be engaged  206  into tissue of the heart valve from both the first side and the second side when the delivery catheter  301 ′ is retracted. This provides for positioning the retention units  105 ,  105 ′, in the correct position at both sides of the valve, without having the risk of damaging the tissue, which otherwise could be the case if the implant  100  and retention units  105 ,  105 ′, thereof would be exposed to the tissue while positioning the implant. Tearing and undesired puncturing of the tissue is thus avoided. A more reliable and secure positioning of the implant  100  at the heart valve  400  is thus achieved. 
     The annuloplasty implant  100 ,  1000 , may be arranged in the delivery catheter  301 ′ along the distal portion of the delivery catheter  301 ′ being bent along the first and second curves  302 ,  303 . Hence, the annuloplasty implant  100 ,  1000 , may be bent along the first and second curves  302 ,  303 , simultaneously with the delivery catheter  301 ′. Alternatively, the annuloplasty implant  100 ,  1000 , may be advanced into the mentioned distal portion of the delivery catheter  301 ′ after the latter has been formed to assume the first and second curves  302 ,  303 , and after retraction of the guide wire from the delivery catheter  301 ′, if a guide wire has been used as described above. Regardless, the annuloplasty implant  100 ,  1000 , is further ejected out from the distal portion while retracting the delivery catheter  301 ′ as explained above and further below with reference to  FIGS. 6 a - c , 7 a - c   . I.e. the implant  100 ,  1000 , remains substantially stationary in the coiled position (defined by the first and second curves  302 ,  303 ) with respect to the valve when the delivery catheter  301 ′ is retracted. The delivery catheter  301 ′ thus defines a path for the implant  100 ,  1000 , that allows for facilitated positioning thereof without having to navigate the implant  100 ,  1000 , into the correct position at the valve. This also provides for an atraumatic positioning of the implant  100 ,  1000 . 
     As mentioned, with reference to  FIGS. 6 a - c   , the first side may be a ventricular side of the heart, and the second side may be the atrial side of the heart. The portions of the delivery catheter  301 ′ arranged on the ventricular side are indicated with dashed lines in  FIGS. 6 a - b   . The first curve  302  of the implant delivery catheter  301 ′ is arranged around chordae of the heart valve on the ventricular side, and the second curve  303  of the delivery catheter  301 ′ is arranged along an annulus of the heart valve on the atrial side. The heart valve may be the mitral valve, and the ventricle may thus be the left ventricle. The method  200  may comprise positioning the delivery catheter  301 ′ in the ventricle by accessing the ventricle through the apex of the heart with an introducer (not shown). The delivery catheter  301 ′ may then then be inserted through the introducer. Alternatively, the method  200  may comprise positioning the delivery catheter  301 ′ in the ventricle by accessing the ventricle through the aortic valve, or by creating access to the left ventricle through the ventricular septum between the right and left ventricle. Regardless, the method  200  comprises in this example forming a first curve  302  of the implant delivery catheter  301 ′ around the chordae of the heart valve on a ventricular side of the heart valve  400 . The delivery catheter  301 ′ may thus be first navigated to the ventricular space between the chordae and the heart muscle, so that the delivery catheter  301 ′ can be curved around the chordae on the ventricular side. The method  200  may comprise inserting the implant delivery catheter  301 ′ through the heart valve  400  to an atrial side thereof, and forming  203  a second curve  303  of the delivery catheter along an annulus of the heart valve on the atrial side. The delivery catheter  301 ′ may be advanced such that annulus is followed in a counter-clockwise direction. In the example of  FIG. 6 a   , the delivery catheter  301 ′ has been inserted through the heart valve  400  to form the second curve  303  on the atrial side. Parts of the delivery catheter  301 ′ on the atrial side has been illustrated with a solid line for clarity of presentation. In  FIG. 6 a   , the delivery catheter  301 ′ has been advanced through the valve  400  at the commissure  401 , and with a distal tip  304  of the delivery catheter  301 ′ positioned as illustrated in  FIG. 6 a   , adjacent the opposite commissure. 
     The method  200  comprises ejecting  204  the annuloplasty implant  100 ,  1000 , from the delivery catheter  301 ′ while retracting  205  the delivery catheter  301 ′ such that the annuloplasty implant  100 ,  1000 , is arranged along the first and second curve on the ventricular and atrial side.  FIG. 6 b    illustrates an example where the implant  100 ,  1000 , has been ejected and the delivery catheter  301 ′ has been retracted back from the atrial side, and through the valve, now having the distal tip  304  arranged at the ventricular side, ready to release the implant  100 ,  1000 . Portions of the implant  100 ,  1000 , on the atrial side are illustrated with solid lines, and portions of the implant  100 ,  1000 , on the ventricular side are illustrated with dashed lines. The implant  100 ,  1000 , is thus abutting the valve tissue on the ventricular and atrial sides of the valve  400 . In one example, when having retention units  105 ,  105 ′, arranged on the annuloplasty implant  100 , the retention units  105 ,  105 ′, may be engaged  206  into tissue of the heart valve from both the ventricular side and the atrial side when the delivery catheter  301 ′ is retracted.  FIG. 6 c    shows the retracted delivery catheter  301 ′ having released the implant  100 . Retention units  105 ,  105 ′, are not shown in  FIGS. 6 a - c   , but the positions of the retention units  105 ,  105 ′, in  FIG. 6 c    may correspond to the illustration in  FIG. 2  in this regard. Since the delivery catheter  301 ′ is simultaneously retracted along the curvature of the first and second curve  302 ,  303 , when ejecting the implant  100 ,  1000 , the positioning of the implant  100 ,  1000 , will effectively correspond to withdrawing the delivery catheter  301 ′ as a sheath previously covering the implant  100 ,  1000 , which already is arranged along the curvature provided by the delivery catheter  301 ′ when forming the first and second curve  302 ,  303 , thereof. Hence, the delivery catheter  301 ′ can effectively serve as a guide for the implant  100 ,  1000 , for the positioning thereof on the ventricular and atrial side, without having to navigate the implant  100 ,  1000 , into the correct position after being ejected from the delivery catheter  301 ′. This provides for improving the control of the positioning of the implant  100 ,  1000 , since otherwise, as soon as an implant is ejected from a delivery catheter, the amount of control and steerability on the ejected part is diminished by the decoupling from the physical constrain of the catheter. Positioning the implant  100 ,  1000 , as described above removes the steerability requirement on the implant  100 ,  1000 , after being ejected, due to the guiding of the implant  100 ,  1000 , to the final position, while being fully confined within the delivery catheter  301 ′. This also minimizes the risk of interference with the surrounding anatomy, such as entanglement of the implant with the chordae. This also provides for positioning retention units  105 ,  105 ′, in the correct position at the valve, without having the risk of damaging the tissue, which otherwise could be the case if the implant  100  and retention units  105 ,  105 ′, thereof would be exposed to the tissue while positioning the implant. Tearing and undesired puncturing of the tissue is thus avoided. A more reliable and secure positioning of the implant  100  at the heart valve  400  is thus achieved. 
     As shown in the example of  FIGS. 7 a - c   , the delivery catheter  301 ′ may be initially positioned in the atrium, via access through the atrial septum, and directed to the anterior commissure  401 . A first curve  302  of the delivery catheter  301 ′ is arranged around chordae of the heart valve on the ventricular side, again returning to the anterior commissure  401  ( FIG. 7 a   ). A second curve  303  of the implant delivery catheter  301 ′ is arranged along an annulus of the heart valve on the atrial side. Again, portions of the implant  100 ,  1000 , on the atrial side are illustrated with solid lines, and portions of the implant  100 ,  1000 , on the ventricular side are illustrated with dashed lines. As mentioned above, a guide wire (not shown) may be arranged in the shape of the first and second curves  302 ,  303 , before advancing the delivery catheter  301 ′ over the guide wire to assume the corresponding shapes on both sides of the valve leaflets. The guide wire and the delivery catheter be initially advanced into the atrium via access through the atrial septum of the heart.  FIG. 7 a    shows the delivery catheter  301  forming the first curve  302  around the valve on the ventricular side, and the distal tip  304  is positioned on the ventricular side.  FIG. 7 b    shows the second curve  303  formed at least partly around the annulus on the atrial side.  FIG. 7 c    shows the delivery catheter  301 ′ partly retracted (see e.g. new position of distal tip  304  on ventricular side), exposing part of a support ring  102  of the annuloplasty implant  100 ,  1000 , on the ventricular side. In the example where the annuloplasty implant  100  comprises retention units  105 ,  105 ′, the retention units  105  on the second support ring  102  (not shown for clarity of presentation) may thus be exposed and can be advanced into the tissue as the delivery catheter  301 ′ is gradually retracted.  FIG. 7 d    shows the annuloplasty implant  100 ,  1000 , just being fully released from the distal tip  304  of the delivery catheter  301 , so that first and second supports  101 ,  102 , of the annuloplasty implant  100  are arranged to contact opposite sides of the valve. The locking structure  503  of the delivery device  301  (not shown in  FIG. 7 d   , see e.g.  FIGS. 13 a - b   ) arranged in the delivery catheter  301 ′ has thus been released from interlocking engagement with the correspondingly mating first locking structure  502  of the delivery device connector  501  of the annuloplasty implant  100 ,  1000 . In one example, retention units  105 ,  105 ′, arranged on the annuloplasty implant  100  may be engaged  207  into tissue of the heart valve from both the ventricular side and the atrial side when the delivery catheter  301 ′ is retracted, without risk of damaging the tissue, since there is no rotational movement of the implant  100 ,  1000 , with respect to the tissue. Further, as with the example in  FIGS. 6 a - c   , the delivery catheter  301 ′ can effectively serve as a guide for the implant  100 ,  1000 , for the positioning thereof on the ventricular and atrial side, without having to navigate the implant  100 ,  1000 , into the correct position after being ejected from the delivery catheter  301 ′. This provides for improving the control of the positioning of the implant  100 ,  1000 . Similarly as described above, a guide wire may be first advanced to assume the first and second curves  302 ,  303 , and the delivery catheter  301 ′ may then be advanced over the guide wire to assume a coiled configuration. The guide wire may then be removed, and the implant  100 ,  1000 , may be inserted into the delivery catheter  301 ′, and thereby guided to assume the coiled configuration of the delivery catheter, which then can be retracted to expose the implant  100 ,  1000 , which can retain the coiled configuration due to a shape memory of the material thereof. 
     In the method  200 , the annuloplasty implant  100  may be kept substantially stationary in relation to the heart valve  400  when being ejected from the delivery catheter  301 ′ while simultaneously retracting the delivery catheter  301 ′ in relation to the annuloplasty implant  100 ,  1000 . As elucidated above, this facilitates positioning of retention units  105 ,  105 ′, if arranged on the annuloplasty implant  100 , without risking damaging the tissue. 
     The annuloplasty implant  100 ,  1000 , may have a predefined shape having a curvature corresponding substantially to the first and second curve  302 ,  303 , such that, when ejected from the delivery catheter  301 ′, the annuloplasty implant  100 ,  1000 , is arranged  207  along the first and second curve  302 ,  303 , as a coil or helix in a coiled configuration, as illustrated in  FIGS. 6 a - c , 7 a - d   . The first and second curve  302 ,  303 , may thus form two continuously connected loops, on opposite sides of the heart valve, being connected through the commissure  401 . This provides for achieving an efficient deployment of an annuloplasty implant  100 ,  1000 , around the annulus of the valve  400 , on both the ventricular and atrial sides. 
     By having a predefined ring-shape approximating the curvature of the first and second curves  302 ,  303 , of the delivery catheter  301 , the annuloplasty implant  100 ,  1000 , may be readily aligned around the heart valve  400  along the extension of the first and second curves  302 ,  303 , when the implant  100 ,  1000 , is ejected and the delivery catheter is simultaneously withdrawn, with a minimum of movement of the implant  100 ,  1000 , relative to the valve  400  when the delivery catheter  301 ′ is withdrawn. A more stable and controlled positioning of the implant  100 ,  1000 , along the annulus of the heart valve  400  may thus be achieved. The predefined ring-shape of the implant  100 ,  1000 , can be determined for example by a heat treatment procedure during manufacturing of the implant  100 ,  1000 . When the implant is confined in the delivery catheter  301 ′, it assumes an elongated configuration, until it is ejected, whereby it assumes the predefined shape, i.e. the relaxed shape of the shape-memory of the material from which the ring is formed. As mentioned above, the implant  100 ,  1000 , may subsequently also assumed a contracted shape where the distance between supports  101 ,  102 , is further reduced in the axial direction  103 , e.g. by the increase of temperature to an activation temperature. This may facilitate fixation of retention units  105 ,  105 ′, into the tissue, in the example where the annuloplasty implant  100  comprises such retention units  105 ,  105 ′. In such case, it is conceivable that the delivery catheter  301 ′ may be withdrawn gradually to slowly expose the retention units  105 ,  105 ′, and allow the temperature of the supports  101 ,  102 , to increase, so that the retention units  105 ,  105 ′ can be gradually pushed into the tissue as the catheter  301 ′ is withdrawn. This provides for increasing the control by which the implant is attached at the valve, hence allowing for a safer implantation procedure. 
     Hence, the method  200 , in both examples of  FIGS. 6 a - c    and  FIGS. 7 a - d   , a first support ring  101  of the coil may be positioned on the atrial side and a second support ring  102  of the coil is positioned on the opposite ventricular side when ejecting the annuloplasty implant from the delivery catheter while retracting the delivery catheter, whereby leaflets of the heart valve are pinched between the first and second support rings  101 ,  102 . 
     The method  200  may comprise activating  209  a contracted state of the annuloplasty implant  100 ,  1000 , so that a first pitch distance (p 1 ) between the first and second support rings  101 ,  102 , is reduced to a second pitch distance (p 2 ), whereby the first and second support rings  101 ,  102 , move towards each other. In case the annuloplasty implant  100  comprises retention units  105 ,  105 ′, the retention units  105 ,  105 ′, may thus be pushed into the tissue. 
     The present invention has been described above with reference to specific embodiments. However, other embodiments than the above described are equally possible within the scope of the invention. The different features and steps of the invention may be combined in other combinations than those described. The scope of the invention is only limited by the appended patent claims. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the teachings of the present invention is/are used.