Patent Description:
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.

Implants have previously been introduced into the coronary sinus (CS) in order to affect the shape of the valve annulus and thereby the valve function. <CIT> discloses such implant that is aimed to replace annuloplasty rings. Implanting annuloplasty devices in the CS is a procedure that entails several challenges, such as re-shaping the annulus in a manner that sustain proper valve function, and ensuring the correct position of the device in the CS over time. Possible traumatic effects on the CS itself have to be taken into account, as well as the complexity of the implant and the procedure. Prior art devices typically have suboptimal performance in several of the aforementioned aspects of annuloplasty via the CS. A problem is to ensure that a significant part of the annulus is reshaped while providing for atraumatic engagement with the anatomy. A problem with the prior art is complex and difficult-to-operate devices, that may require frequent adjustment and repositioning to ensure the correct function over time. This may have dire consequences for the patient and the health care system. Patient risk is increased.

<CIT> discloses stents having a tubular elongate body with a proximal section, central section, and a distal section. The stent is deployed by mounting the distal section on a first balloon which is inflated to expand the distal section. A second and third balloon are inserted and inflated to expand the proximal and central sections, respectively. The expansion of the central section pulls the distal and proximal sections toward each other.

It is desirable to increase the degree of control of the downsizing procedure, i.e. the re-shaping of the annulus, while ensuring a secure anchoring of the implant and minimal risk of damage to the CS.

Hence, an improved annuloplasty device for performing downsizing and reshaping of the valve annulus would be advantageous and in particular allowing for ensuring long-term functioning, less complex procedure, and less traumatic effects on the anatomy and increased patient safety. Also, a method of downsizing and reshaping the mitral valve annulus with such annuloplasty device would be advantageous.

The invention is a device as defined in claims <NUM>-<NUM>. 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 an annuloplasty device for treating a defective mitral valve having an annulus is provided, comprising a removable and flexible elongate displacement unit for temporary insertion into a coronary sinus (CS) adjacent the valve, wherein the displacement unit has a delivery state for delivery into the CS, and an activated state to which the displacement unit is temporarily and reversibly transferable from said delivery state, a proximal reversibly expandable portion being reversibly foldable to an expanded state for positioning against a tissue wall at the entrance of the CS, wherein the displacement unit comprises a distal anchoring portion being movable in relation to the proximal expandable portion in a longitudinal direction of the displacement unit to said activated state in which the shape of the annulus is modified to a modified shape when inserted into the CS, a stent arranged around the displacement unit and being movable relative the displacement unit along the longitudinal direction for insertion into the CS, and wherein the stent is releasably connected to a delivery device and arranged radially between the displacement unit and the proximal expandable portion in a radial direction (R), the radial direction (R) being perpendicular to the longitudinal direction.

Further examples of the invention are defined in the dependent claims.

Some examples of the disclosure provide for long-term functioning of a repaired mitral valve.

Some examples of the disclosure provide for less complex downsizing procedures of the mitral valve.

Some examples of the disclosure provide for improved control of the downsizing procedure of the mitral valve.

Some examples of the disclosure provide for a reduced risk of damaging the anatomy such as the CS.

Some examples of the disclosure provide for a secure downsizing while at the same time reducing the risk of damaging the anatomy such as the CS.

Some examples of the disclosure provide for improved downsizing of the mitral valve annulus while ensuring an atraumatic procedure.

Some examples of the disclosure provide for reduced risk of long-term negative effects of CS implants.

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.

<FIG> schematically illustrates an annuloplasty device <NUM> for treating a defective mitral valve having an annulus. The annuloplasty device <NUM> comprises a removable and flexible elongate displacement unit <NUM> for temporary insertion into a coronary sinus (CS) adjacent the mitral valve. The displacement unit <NUM> has a delivery state for delivery into the CS, and an activated state to which the displacement unit <NUM> is temporarily and reversibly transferable from said delivery state. The annuloplasty device <NUM> comprises a proximal reversibly expandable portion <NUM>. The proximal expandable portion <NUM> is reversibly foldable to an expanded state for positioning against a tissue wall at the entrance of the CS. <FIG> show an example where the proximal expandable portion <NUM> moves from a collapsed state in <FIG>, to an expanded state in <FIG>. <FIG> illustrates schematically how the proximal expandable portion <NUM> is positioned outside the CS, for pushing against the wall at the entrance of the CS. The displacement unit <NUM> comprises a distal anchoring portion <NUM> being movable in relation to the proximal expandable portion <NUM> in a longitudinal direction <NUM> of the displacement unit <NUM> to the aforementioned activated state. <FIG> illustrates schematically how the distal anchoring portion <NUM> is anchored in the CS. The distal anchoring portion <NUM> may be anchored in the great cardiac vein. <FIG> illustrate an example where the distal anchoring portion <NUM> is movable such that a distance between the proximal expandable portion <NUM> and the distal anchoring portion <NUM> is varied. The distance is reduced from a length denoted L in <FIG> to a reduced length denoted L' in <FIG>. In the activated state, the annuloplasty device <NUM>, when placed in the CS, modifies the annulus to a modified shape where the annulus is downsized and the leaflets may co-apt. Thus, when the annuloplasty device <NUM> is placed in the CS as exemplified in <FIG>, and the distal anchoring portion <NUM> is anchored, the latter may be withdrawn towards the proximal expandable portion <NUM> which exerts a counter force against the tissue wall at the entrance of the CS. This allows for re-shaping the annulus of the mitral valve.

Turning again to <FIG>, the annuloplasty device <NUM> comprises a stent <NUM> arranged around the displacement unit <NUM> and being movable relative the displacement unit <NUM> along the longitudinal direction <NUM> for insertion into the CS. <FIG> illustrate schematically how the stent <NUM> is advanced over the displacement unit <NUM> towards the distal anchoring portion <NUM>. <FIG> illustrate the position of the stent <NUM> over the displacement unit <NUM> when the annuloplasty device <NUM> is placed in the CS. The stent <NUM> may be expanded for anchoring into the CS when the displacement unit <NUM> has re-shaped the annulus, as illustrated in <FIG> and described further below. The stent <NUM> is releasably connected to a delivery device <NUM> as schematically indicated in <FIG> and <FIG>, and may be released in the CS to maintain the re-shaped form of the annulus after the displacement unit <NUM> has been withdrawn, as illustrated in <FIG>, and <FIG> is an illustration of the heart showing the CS in relation to the mitral valve (MV) in a top-down view. The CS lies adjacent the MV and follows a curvature around the annulus (A) of the MV. The stent <NUM> may have a releasable connection <NUM> to the delivery device <NUM> as exemplified in <FIG>. It is conceivable that the delivery device <NUM> may be configured push or pull the stent <NUM> relative the displacement unit <NUM> along the longitudinal direction <NUM>. The stent <NUM> is arranged radially between the displacement unit <NUM> and the proximal expandable portion <NUM> in a radial direction (R), as illustrated in e.g. <FIG>. The radial direction (R) is perpendicular to the longitudinal direction <NUM>. Having the stent <NUM> arranged between the displacement unit <NUM> and the proximal expandable portion <NUM> allows for advancing the stent <NUM> over the displacement unit <NUM> into the CS while the proximal expandable portion <NUM> is expanded at the outside of the CS and the displacement unit <NUM> is in the activated state. The re-shaping of the annulus may thus be carefully controlled and optimized with the displacement unit <NUM>, by varying the length (L), before the stent <NUM> is positioned and finally anchored in the CS. Once the leaflets co-apt properly and no regurgitation occurs, e.g. by observing flow characteristics and leaflet movement, the stent <NUM> may be expanded gradually (<FIG>), e.g. by withdrawing a catheter <NUM> arranged over the stent <NUM>, as described further below. Connection to the stent <NUM> can be maintained with the delivery device <NUM> after the stent <NUM> has been fully expanded (<FIG>). The force exerted by the displacement unit <NUM> on the annulus may then be gradually released, e.g. by reducing the tension between the proximal expandable portion <NUM> and the distal anchoring portion <NUM>. The flow characteristics and leaflet movement may be continuously observed to ensure no regurgitation occurs. The displacement unit <NUM> can be fully withdrawn through the stent <NUM> (<FIG>), and the stent <NUM> can be released (<FIG>) if no regurgitation occurs. Otherwise the stent <NUM> may be captured, e.g. by advancing a catheter <NUM> overt the stent <NUM>, and the re-shaping of the annulus may be adjusted further with the displacement unit <NUM>, and/or another stent <NUM> of a different size may be introduced through the proximal expandable portion <NUM> and over the displacement unit <NUM> to repeat the procedure.

It is conceivable that the stent <NUM> may be advanced through the proximal expandable portion <NUM> and over the displacement unit <NUM> into the CS (<FIG>), before or after the displacement unit <NUM> has re-shaped the annulus. Regardless, the stent <NUM> is expanded and fixed in the CS after the re-shaping has been performed.

The annuloplasty device <NUM> thus provides for a facilitated annuloplasty procedure via the CS. The re-shaping of the annulus can be carefully controlled and optimized with the displacement unit <NUM> and the stent <NUM> can be anchored in the CS to maintain the modified shape when the proper valve function can be confirmed. The safety of the procedure is improved as the position of the stent <NUM> relative the displacement unit <NUM> and the CS can be varied and optimized while the displacement unit <NUM> already provides the downsizing effect of the valve in the activated state. The need to introduce complex elements into the implanted device, i.e. the stent, in order to provide downsizing of the valve can be dispensed with due to the above described cooperation between the displacement unit <NUM> and the stent <NUM>. The stent <NUM> may thus be more robust and less complex, and therefore more reliable in sustaining the desired function of the valve over time. Prior art implants may on the contrary require reoccurring adjustments, due to a complex interplay between several moving parts in order to provide downsizing of the annulus. The annuloplasty device <NUM> provides also for reducing the risk of damaging the CS as the downsizing may be provided by an atraumatically shaped displacement unit <NUM>, instead of the stent <NUM> which may have retention units <NUM> as described further below. The risk of tearing of the tissue in the CS with such retention units may thus be reduced.

As described, the distance (L) between the proximal expandable portion <NUM> and the distal anchoring portion <NUM> in the longitudinal direction <NUM> may decrease to a reduced distance (L') when the displacement unit <NUM> is transferred from the delivery state to the activated state. The proximal expandable portion <NUM> and the distal anchoring portion <NUM> may be connected to different sheaths or wires, that may be independently movable in the longitudinal direction <NUM> to provide for varying the distance (L) as illustrated in <FIG>.

The proximal expandable portion <NUM> may be connected to a sheath <NUM> and may be configured to be expanded in a radial direction (R), perpendicular to the longitudinal direction <NUM>, by pushing a proximal portion <NUM> of the sheath <NUM> towards the distal anchoring portion <NUM>, as indicated in <FIG> (see arrow adjacent sheath <NUM>). This provides for a facilitated deployment of the expandable portion <NUM> to the expanded configuration.

As the displacement unit <NUM> is positioned with a separation (L') between the proximal expandable portion <NUM> and the distal anchoring portion <NUM> that provides the desired downsizing of the valve, the stent <NUM> is movable into position over the displacement unit <NUM> for positioning and anchoring into the CS. The annuloplasty device <NUM> may comprise a catheter <NUM> to enclose the stent <NUM> and position the stent <NUM> relative the displacement unit <NUM> in the longitudinal direction <NUM>, as schematically illustrated in <FIG>, and <FIG>. <FIG> show an example where the catheter <NUM> is first advanced over the displacement unit <NUM>, before the stent <NUM> is pushed forward inside the catheter <NUM> by a delivery device <NUM>. It is conceivable however that the stent <NUM> may be advanced over the displacement unit <NUM> at the same time as the catheter <NUM>. The stent <NUM> may be ejectable from, and retrievable into, the catheter <NUM> by the aforementioned delivery device <NUM>. <FIG> is a schematic illustration where the catheter <NUM> has been withdrawn to expose the stent <NUM> over the displacement unit <NUM>. <FIG> is a schematic illustration where the displacement unit <NUM> has been withdrawn through the stent <NUM>. The proximal expandable portion <NUM> is collapsed and the stent <NUM> may be released from the delivery device <NUM>.

The catheter <NUM> may thus be movable inside the sheath <NUM> in the longitudinal direction <NUM>. The stent <NUM> may thus be positioned at the desired position over the displacement unit <NUM> while the proximal expandable portion <NUM>, being connected to the sheath <NUM>, is expanded and anchored against the entrance of the CS.

The catheter <NUM> may thus be movable over the displacement unit <NUM>, and inside said sheath <NUM>, in the longitudinal direction <NUM>, in the aforementioned activated state. This provides for an efficient and reliable positioning and deployment of the stent <NUM> in the CS while the amount of downsizing of the annulus is effectively controlled by the displacement unit <NUM>.

The stent <NUM> may be reversibly expandable in the radial direction (R) in the activated state. Thus, once expanded, e.g. as illustrated in the (partly) expanded state in <FIG>, the stent <NUM> may be collapsed and retrieved again if needed in order to reposition or replacing the stent <NUM>. For retrieval, the stent <NUM> may be pulled into the catheter <NUM> by withdrawing delivery device <NUM> relative the catheter <NUM>, thereby forcing the stent <NUM> into the confinement of the catheter <NUM>. The stent <NUM> may be self-expandable such that it strives towards an expanded diameter once being release from the catheter <NUM>. The stent <NUM> may in such case be formed from a shape memory material which has been heat set in an expanded diameter configuration where the diameter is larger than the diameter of the CS. The stent <NUM> may be compressed and inserted into the catheter <NUM> before being ejected in the CS where the stent <NUM> will strive towards the heat set shape and thus press against the tissue walls inside the CS. It is also conceivable that the stent <NUM> may be actively expanded by e.g. a balloon catheter pushing inside the stent <NUM> to expand its diameter.

The stent <NUM> may comprise retention units <NUM> to anchor the stent <NUM> in the CS, as schematically illustrated in <FIG>, <FIG>, and <FIG>. Thus, once the displacement unit <NUM> has contracted the tissue around the CS to re-shape the annulus, by shortening from a length (L) to a reduced length (L') (<FIG>), the shape of the remodelled tissue may be retained by the stent <NUM> which is anchored into the tissue. Having retention units <NUM> provides for an effective and reliable anchoring of the stent <NUM> into the tissue. The stent <NUM> may extend with an uninterrupted length in abutment with the tissue wall of the CS, along the majority of the length of the CS. This provides for a reliable retention of the re-shaped annulus over time, in particular when having retention units <NUM> extending essentially along the full length of the stent <NUM>. The stent <NUM> may have a length that corresponds essentially to the length of the CS, as schematically indicated in <FIG>. Retention units <NUM> may be provided along the length of the stent <NUM>. This further provides for particularly reliable retention of the reshaped annulus over time.

The retention units <NUM> may be arranged on a surface section <NUM> of the stent <NUM> being adapted to be arranged towards the annulus when the stent <NUM> is in the CS, as schematically indicated in the top-down view of <FIG> in conjunction with <FIG> showing a cross-section of the stent <NUM> in one example. The retention units <NUM> may thus be arranged at a determined circle sector (v) on the surface of the stent as indicated in <FIG>. Having the retention units <NUM> arranged in a direction towards the annulus provides for an effective retention of the tissue along the corresponding segment of the CS and a reliable retention of the modified annulus shape. The stent <NUM> may comprise at least one radiopaque marker (not shown) in one example. This provides for a facilitated orienting of the stent <NUM> in relation to the direction of the annulus.

It is conceivable that a plurality of retention units <NUM> may be arranged around the circumference of the stent <NUM> in one example. Retention units <NUM> may thus be arranged at a plurality of circle sectors (v) along the circumference of the stent <NUM>. This may be advantageous in some applications where an increased retention force is desirable.

The retention units <NUM> may be shaped to pierce into tissue in the CS and thereby provide a retention force into the tissue. The retention units <NUM> may be formed from the material of the stent <NUM>. The retention units <NUM> may thus be integrated with the stent <NUM>. The retention units <NUM> may thus be cut as respective elongated structures with piercing tips within the structural framework of the stent <NUM>. Forming the retention units <NUM> as integrated structures of the framework of the stent <NUM> provides for robust and strong retention units <NUM> and a minimized risk of dislocations or deformations thereof over time. An overall robust and reliable fixation mechanism is thus provided. The retention units <NUM> may be formed by different cutting techniques such as by laser cutting techniques.

The retention units <NUM> may be resiliently moveable from a retracted state to an expanded state. Thus, the retention units <NUM> may be flexible to bend from the expanded state to the retracted state when arranged inside the catheter <NUM>, and to expand from the retracted state to the expanded state when released from the catheter <NUM>. This provides for a facilitated delivery of the stent <NUM> through the catheter <NUM>, while allowing for expansion and anchoring of the retention units <NUM> into the tissue once deployed from the confinement of the catheter <NUM>. The retention units <NUM> may thus be heat-set to assume a defined expanded shape, as indicated in e.g. <FIG>. The expanded shape may thus correspond to a relaxed state of the retention unit <NUM> where the latter is not acted upon by external forces. The retention unit <NUM> may thus have a bias towards the expanded shape, by striving towards the relaxed expanded state, when released from the catheter <NUM>.

The retention units <NUM> may be are aligned essentially flush with an outer diameter of the stent in the retracted state. This provides further for a facilitated delivery of the stent <NUM> through the catheter <NUM>, as friction between the retention units <NUM> and the inside lumen of the catheter <NUM> may be reduced. Further, a compact cross-section is provided and a minimized risk of abrasion and damage to the catheter <NUM>.

In one example the retention units <NUM> may comprise a shape-memory material, where activation of the shape-memory material causes the retention units <NUM> to transfer from the retracted state to the expanded state. For example, the shape-memory material may be temperature activated, so that the retention units <NUM> move towards the expanded state when subject to heating to the body temperature. This provides for an advantageous deployment of the retention units <NUM> in some applications.

The distal anchoring portion <NUM> may comprise an inflatable unit, such as a balloon, which is expandable in the radial direction (R). This provides for efficient and non-traumatic fixation of the distal end of the displacement unit <NUM>, which in combination with the efficient anchoring against the wall of the CS by the proximal portion <NUM>, allows for an efficient transfer of a contracting force of the proximal and distal portions <NUM>, <NUM>, towards each other. This allows for an effective modification of the radius of curvature of the CS to facilitate modifying the shape of the valve annulus. The annuloplasty device <NUM> may comprise an inflation lumen (not shown) connected to the inflatable unit and being configured to deliver an inflation medium to the inflatable unit.

The length of inflatable unit <NUM> may be adapted to varying anatomies. The length of the inflatable unit <NUM> may be chosen so that it does not block vessels connecting to the CS, e.g. if the inflatable unit <NUM> is anchored further into the CS, such as towards the great cardiac vein/left coronary vein. The length of the inflatable unit <NUM> may also be adapted so that it may be effectively anchored behind the bend or "corner" of the CS as it transitions into the great cardiac vein/left coronary vein. The length of the inflatable unit <NUM> may be sufficiently short to facilitate such anchoring and avoid slipping out of this bend or "corner" of the CS.

The proximal expandable portion <NUM> may comprise expandable bows or ribs <NUM>. The sheath <NUM> may be pushed in relation to a distal portion <NUM> attached distally to the bows or ribs <NUM>. The compressive force between the distal portion <NUM> and the proximal portion <NUM> may thus push the bows <NUM> radially outwards. It is conceivable however that the bows <NUM> may comprise a shape-memory material having a tendency to assume the expanded configuration in its relaxed state, and that the bows may be confined in an outer sheath (not shown) being pulled back so that the bows <NUM> spring into the expanded configuration.

Having expandable bows <NUM> provides for to further lessen the risk of damaging the tissue at the entrance of the CS, since a soft apposition against the tissue may be provided, in absence of sharp edges or kinks. The bows <NUM> may extend in the longitudinal direction <NUM> which facilitates a symmetric engagement against the tissue wall, with an even transfer of force around the entrance to the CS, hence allowing for a robust anchoring. The longitudinal extension of the bows <NUM> also provides for facilitated expansion of the bows <NUM> by applying a force to the bows <NUM> in the longitudinal direction <NUM>. A plurality of bows <NUM> may be arranged circumferentially so that a force may be applied symmetrically and evenly around the tissue wall.

The proximal expandable portion <NUM> may comprise elongated ribs <NUM> formed in the sheath <NUM> by elongated cuts <NUM> in the sheath <NUM>, extending in the longitudinal direction <NUM>, as schematically illustrated in <FIG>. The ribs <NUM> may be foldable to expand in the radial direction (R). This provides for a simple and robust construction. The ribs or bows <NUM> may thus be formed from the same material as the sheath <NUM>. The mentioned material may be a soft flexible material which is non-traumatic to tissue. In the collapsed configuration seen in <FIG>, the ribs <NUM>, i.e. the soon to be expanded ribs <NUM>, extend in the longitudinal direction <NUM>, and provides for a compact radial profile. The ribs or bows <NUM> may be placed equidistantly around a circumference of the sheath <NUM>. As elucidated above, this may provide for an even distribution of the anchoring force.

The maximum expanded diameter (D) of the proximal expandable portion <NUM> may be at least three times the diameter of the CS. In some examples the ratio of the maximum expanded diameter (D) of the proximal expandable portion <NUM> to the diameter of the CS is in the range <NUM> - <NUM>. In some examples the aforementioned ratio may be in the range <NUM> - <NUM>, which provides for a particular advantageous anchoring of the proximal expandable portion <NUM>, while maintaining a compact and easy to use annuloplasty device <NUM>.

The annuloplasty device <NUM> may comprise a guide wire <NUM> arranged to extend inside a lumen <NUM> of the displacement unit <NUM> and to exit the lumen <NUM> at a distal opening <NUM> of the displacement unit <NUM>, as schematically illustrated in <FIG>. The guide wire <NUM> may be inserted into the CS and the displacement unit <NUM> may subsequently be advanced over the guide wire <NUM> for positioning in the CS. This provides for a facilitated positioning of the displacement unit <NUM>.

<FIG> illustrates a method <NUM> for treating a defective mitral valve. The order in which the steps of the method <NUM> are illustrated should not be construed as limiting and it is conceivable that the order in which the steps of the method <NUM> is carried out may be varied. The method <NUM> comprises inserting <NUM> a flexible and removable elongate displacement unit <NUM> in a delivery state into a coronary sinus CS adjacent said valve; positioning <NUM> a proximal reversibly expandable portion <NUM> against a tissue wall at the entrance of said CS (<FIG>); anchoring <NUM> a distal anchoring portion <NUM> inside the CS (<FIG>); activating <NUM> the displacement unit <NUM> in an activated state whereby the distal anchoring portion <NUM> is moved in a longitudinal direction <NUM> of the displacement unit <NUM> to reduce a distance (L) between the distal anchoring portion <NUM> and the proximal expandable portion <NUM> such that the shape of the annulus is modified to a modified shape. The method <NUM> further comprises advancing <NUM> a stent <NUM> through the proximal expandable portion <NUM> and over the displacement unit <NUM> into the CS (<FIG>); anchoring <NUM> the stent <NUM> in the CS to retain the modified shape of the annulus (<FIG>); withdrawing <NUM> the displacement unit <NUM> through the stent <NUM> to remove <NUM> the displacement unit <NUM> after temporary activation in the activated state (<FIG>, <FIG>). The method <NUM> thus provides for the advantageous benefits as described above in relation to the annuloplasty device <NUM> and <FIG>. The method <NUM> provides for an improved annuloplasty procedure with an increase in the degree of control of the downsizing procedure, while ensuring secure anchoring of the stent <NUM> and minimal risk of damage to the CS. Advancing the stent <NUM> over the displacement unit <NUM> into the CS while the proximal expandable portion <NUM> is expanded at the outside of the CS and the displacement unit <NUM> is in the activated state provides for a secure positioning and fixation of the stent <NUM> when the valve is already re-shaped by the displacement unit <NUM>. A particularly robust and reliable annuloplasty procedure is thus provided.

<FIG> illustrates another flow chart of a method <NUM> for treating a defective mitral valve. The order in which the steps of the method <NUM> are illustrated should not be construed as limiting and it is conceivable that the order in which the steps of the method <NUM> is carried out may be varied.

The distal anchoring portion <NUM> may comprise an inflatable unit, also denoted with reference numeral <NUM>. Anchoring the distal anchoring portion <NUM> may comprise inflating <NUM> the inflatable unit <NUM> in the coronary sinus, and/or in the great cardiac vein and/or, in the anterior interventricular branch or vein, and/or in the posterior vein and/or in the posterior ventricular vein of the heart.

The proximal expandable portion <NUM> may be connected to a sheath <NUM>. Positioning the proximal expandable portion <NUM> may comprise pushing <NUM> a proximal portion <NUM> of the sheath <NUM> towards the distal anchoring portion <NUM> to expand the proximal expandable portion <NUM> in a radial direction (R).

Anchoring the stent <NUM> may comprise withdrawing <NUM> a catheter <NUM> enclosing the stent <NUM> and expanding <NUM> the stent <NUM> in a radial direction (R) being perpendicular to the longitudinal direction <NUM>, as schematically illustrated in <FIG>.

The catheter <NUM> may be is movable through the proximal expandable portion <NUM> and over the displacement unit <NUM> in the longitudinal direction <NUM>, providing for the advantageous effects as described above.

Anchoring the stent <NUM> may comprise anchoring <NUM> retention units <NUM> of the stent <NUM> into the CS to retain the modified shape of the annulus when the displacement unit <NUM> is withdrawn, as schematically illustrated in <FIG>.

Anchoring the retention units <NUM> may comprise anchoring <NUM> the retention units <NUM> in a tissue wall of the CS in the direction of the annulus.

The method <NUM> may comprise advancing <NUM> the catheter <NUM> over the stent <NUM> to disengage the stent <NUM> from the CS for repositioning or removal of the stent <NUM> from the CS.

Anchoring the stent <NUM> may comprise releasing <NUM> the stent <NUM> from a delivery device <NUM> movably arranged inside the catheter <NUM> (<FIG>). the invention is only limited by the appended patent claims.

Claim 1:
An annuloplasty device (<NUM>) for treating a defective mitral valve having an annulus, comprising
a removable and flexible elongate displacement unit (<NUM>) for temporary insertion into a coronary sinus (CS) adjacent the valve, wherein the displacement unit has a delivery state for delivery into the CS, and an activated state to which the displacement unit is temporarily and reversibly transferable from said delivery state,
a proximal reversibly expandable portion (<NUM>) being reversibly foldable to an expanded state for positioning against a tissue wall at the entrance of the CS,
wherein the displacement unit comprises a distal anchoring portion (<NUM>) being movable in relation to the proximal expandable portion in a longitudinal direction (<NUM>) of the displacement unit to said activated state in which the shape of the annulus is modified to a modified shape when inserted in the CS,
a stent (<NUM>) arranged around the displacement unit and being movable relative the displacement unit along the longitudinal direction for insertion into the CS, and
wherein the stent is releasably connected to a delivery device (<NUM>) and arranged radially between the displacement unit and the proximal expandable portion in a radial direction (R), the radial direction (R) being perpendicular to the longitudinal direction, wherein the stent comprises retention units (<NUM>) to anchor the stent in the CS, characterized in that the proximal expandable portion is connected to a sheath (<NUM>) and is configured to be expanded in the radial direction (R) by pushing a proximal portion (<NUM>) of the sheath towards the distal anchoring portion.