This invention pertains in general to the field of annuloplasty devices for treating a defective mitral valve. More particularly the invention relates to an annuloplasty device for treating a defective mitrel valve via coronary sinus, and a method therefore.
Diseased mitrel and tricuspid valves frequently need replacement or repair. The mitrel and tricuspid valve leaflets or supporting chordae may degenerate and weaken or the annulus may dilate leading to valve leak. Mitrel 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. WO02/062270 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.
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.
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.
According to a second aspect a method for treating a defective mitral valve having an annulus is provided, said method comprising: inserting a flexible and removable elongate displacement unit in a delivery state into a coronary sinus (CS) adjacent said valve, positioning a proximal reversibly expandable portion against a tissue wall at the entrance of said CS, anchoring a distal anchoring portion inside the CS, activating the displacement unit in an activated state whereby the distal anchoring portion is moved in a longitudinal direction of the displacement unit to reduce a distance (L) between the distal anchoring portion and the proximal expandable portion such that the shape of the annulus is modified to a modified shape, advancing a stent through the proximal expandable portion and over the displacement unit into the CS, anchoring the stent in the CS to retain the modified shape of the annulus, withdrawing the displacement unit through the stent to remove the displacement unit after temporary activation in the activated state.
Further examples of the invention are defined in the dependent claims, wherein features for the second and subsequent aspects are as for the first aspect mutatis mutandis.
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 mitrel valve annulus while ensuring an atraumatic procedure.
Some examples of the disclosure provide for reduced risk of long-term negative effects of CS implants.
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.
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
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.
Turning again to
It is conceivable that the stent 105 may be advanced through the proximal expandable portion 102 and over the displacement unit 101 into the CS (
The annuloplasty device 100 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 101 and the stent 105 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 105 relative the displacement unit 101 and the CS can be varied and optimized while the displacement unit 101 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 101 and the stent 105. The stent 105 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 100 provides also for reducing the risk of damaging the CS as the downsizing may be provided by an atraumatically shaped displacement unit 101, instead of the stent 105 which may have retention units 110 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 102 and the distal anchoring portion 103 in the longitudinal direction 104 may decrease to a reduced distance (L′) when the displacement unit 101 is transferred from the delivery state to the activated state. The proximal expandable portion 102 and the distal anchoring portion 103 may be connected to different sheaths or wires, that may be independently movable in the longitudinal direction 104 to provide for varying the distance (L) as illustrated in
The proximal expandable portion 102 may be connected to a sheath 107 and may be configured to be expanded in a radial direction (R), perpendicular to the longitudinal direction 104, by pushing a proximal portion 108 of the sheath 107 towards the distal anchoring portion 103, as indicated in
As the displacement unit 101 is positioned with a separation (L′) between the proximal expandable portion 102 and the distal anchoring portion 103 that provides the desired downsizing of the valve, the stent 105 is movable into position over the displacement unit 101 for positioning and anchoring into the CS. The annuloplasty device 100 may comprise a catheter 109 to enclose the stent 105 and position the stent 105 relative the displacement unit 101 in the longitudinal direction 104, as schematically illustrated in
The catheter 109 may thus be movable inside the sheath 107 in the longitudinal direction 104. The stent 105 may thus be positioned at the desired position over the displacement unit 101 while the proximal expandable portion 102, being connected to the sheath 107, is expanded and anchored against the entrance of the CS.
The catheter 109 may thus be movable over the displacement unit 101, and inside said sheath 107, in the longitudinal direction 104, in the aforementioned activated state. This provides for an efficient and reliable positioning and deployment of the stent 105 in the CS while the amount of downsizing of the annulus is effectively controlled by the displacement unit 101.
The stent 105 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
The stent 105 may comprise retention units 110 to anchor the stent 105 in the CS, as schematically illustrated in
The retention units 110 may be arranged on a surface section 111 of the stent 105 being adapted to be arranged towards the annulus when the stent 105 is in the CS, as schematically indicated in the top-down view of
It is conceivable that a plurality of retention units 110 may be arranged around the circumference of the stent 105 in one example. Retention units 110 may thus be arranged at a plurality of circle sectors (v) along the circumference of the stent 105. This may be advantageous in some applications where an increased retention force is desirable.
The retention units 110 may be shaped to pierce into tissue in the CS and thereby provide a retention force into the tissue. The retention units 110 may be formed from the material of the stent 105. The retention units 110 may thus be integrated with the stent 105. The retention units 110 may thus be cut as respective elongated structures with piercing tips within the structural framework of the stent 105. Forming the retention units 110 as integrated structures of the framework of the stent 105 provides for robust and strong retention units 110 and a minimized risk of dislocations or deformations thereof over time. An overall robust and reliable fixation mechanism is thus provided. The retention units 110 may be formed by different cutting techniques such as by laser cutting techniques.
The retention units 110 may be resiliently moveable from a retracted state to an expanded state. Thus, the retention units 110 may be flexible to bend from the expanded state to the retracted state when arranged inside the catheter 109, and to expand from the retracted state to the expanded state when released from the catheter 109. This provides for a facilitated delivery of the stent 105 through the catheter 109, while allowing for expansion and anchoring of the retention units 110 into the tissue once deployed from the confinement of the catheter 109. The retention units 110 may thus be heat-set to assume a defined expanded shape, as indicated in e.g.
The retention units 110 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 105 through the catheter 109, as friction between the retention units 110 and the inside lumen of the catheter 109 may be reduced. Further, a compact cross-section is provided and a minimized risk of abrasion and damage to the catheter 109.
In one example the retention units 110 may comprise a shape-memory material, where activation of the shape-memory material causes the retention units 110 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 110 move towards the expanded state when subject to heating to the body temperature. This provides for an advantageous deployment of the retention units 110 in some applications.
The distal anchoring portion 103 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 101, which in combination with the efficient anchoring against the wall of the CS by the proximal portion 102, allows for an efficient transfer of a contracting force of the proximal and distal portions 102, 103, 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 100 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 103 may be adapted to varying anatomies. The length of the inflatable unit 103 may be chosen so that it does not block vessels connecting to the CS, e.g. if the inflatable unit 103 is anchored further into the CS, such as towards the great cardiac vein/left coronary vein. The length of the inflatable unit 103 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 103 may be sufficiently short to facilitate such anchoring and avoid slipping out of this bend or “corner” of the CS.
The proximal expandable portion 102 may comprise expandable bows or ribs 112. The sheath 107 may be pushed in relation to a distal portion 114 attached distally to the bows or ribs 112. The compressive force between the distal portion 114 and the proximal portion 108 may thus push the bows 112 radially outwards. It is conceivable however that the bows 112 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 112 spring into the expanded configuration.
Having expandable bows 112 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 112 may extend in the longitudinal direction 104 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 112 also provides for facilitated expansion of the bows 112 by applying a force to the bows 112 in the longitudinal direction 104. A plurality of bows 112 may be arranged circumferentially so that a force may be applied symmetrically and evenly around the tissue wall.
The proximal expandable portion 102 may comprise elongated ribs 112 formed in the sheath 107 by elongated cuts 113 in the sheath 107, extending in the longitudinal direction 104, as schematically illustrated in
The maximum expanded diameter (D) of the proximal expandable portion 102 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 102 to the diameter of the CS is in the range 3-5. In some examples the aforementioned ratio may be in the range 3.5-4.5, which provides fora particular advantageous anchoring of the proximal expandable portion 102, while maintaining a compact and easy to use annuloplasty device 100.
The annuloplasty device 100 may comprise a guide wire 115 arranged to extend inside a lumen 116 of the displacement unit 101 and to exit the lumen 116 at a distal opening 117 of the displacement unit 101, as schematically illustrated in
The distal anchoring portion 103 may comprise an inflatable unit, also denoted with reference numeral 103. Anchoring the distal anchoring portion 103 may comprise inflating 4031 the inflatable unit 103 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 102 may be connected to a sheath 107. Positioning the proximal expandable portion 102 may comprise pushing 4021 a proximal portion 108 of the sheath 107 towards the distal anchoring portion 103 to expand the proximal expandable portion 102 in a radial direction (R).
Anchoring the stent 105 may comprise withdrawing 4061 a catheter 109 enclosing the stent 105 and expanding 4062 the stent 105 in a radial direction (R) being perpendicular to the longitudinal direction 104, as schematically illustrated in
The catheter 109 may be is movable through the proximal expandable portion 102 and over the displacement unit 101 in the longitudinal direction 104, providing for the advantageous effects as described above.
Anchoring the stent 105 may comprise anchoring 4063 retention units 110 of the stent 105 into the CS to retain the modified shape of the annulus when the displacement unit 101 is withdrawn, as schematically illustrated in
Anchoring the retention units 110 may comprise anchoring 4064 the retention units 110 in a tissue wall of the CS in the direction of the annulus.
The method 400 may comprise advancing 4065 the catheter 109 over the stent 105 to disengage the stent 105 from the CS for repositioning or removal of the stent 105 from the CS.
Anchoring the stent 105 may comprise releasing 4066 the stent 105 from a delivery device 106 movably arranged inside the catheter 109 (
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.
Number | Date | Country | Kind |
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20212594.4 | Dec 2020 | EP | regional |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2021/084866 | 12/8/2021 | WO |
Number | Date | Country | |
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63122675 | Dec 2020 | US |