Bent wheel forming device

Abstract

Disclosed is an annuloplasty device comprising: a removable, flexible, elongated displacement unit inserted into a coronary sinus (CS) adjacent to a mitral valve; a proximal reversibly expandable portion reversibly foldable into an expanded state for positioning against a tissue wall at the entrance of the CS; a distal fixation portion movable in the longitudinal direction of the displacement unit relative to the proximal expandable portion to the actuated state for modifying the shape of the valve annulus into a modified shape; and a stent disposed around the displacement unit and movable along the longitudinal direction relative to the displacement unit for insertion into the CS, the stent being detachably connected to a delivery device and radially disposed between the displacement unit and the proximal expandable portion.

Description

【Technical Field】 【0001】 The present invention generally relates to the field of annuloplasty devices for treating defective mitral valves. More specifically, the present invention relates to an annuloplasty device for treating a defective mitral valve via the coronary sinus, and a method thereof. 【Background Art】 【0002】 Affected mitral and tricuspid valves often require frequent replacement or repair. The mitral and tricuspid valve leaflets or supporting chordae tendineae may degenerate and become weak, or the annulus may dilate and cause valvular regurgitation. Replacement and repair of the mitral and tricuspid valves are often performed under the assistance of an annulus ring that is used to reduce the diameter of the annulus or otherwise change the shape of the annulus as an overall support structure during valve replacement or repair procedures. 【0003】 Previously, implants have been introduced into the coronary sinus (CS) to affect the shape of the annulus and thereby affect valve function. WO02 / 062270 discloses such an implant for the purpose of replacing an annuloplasty ring. Implanting an annuloplasty device inside the CS is a procedure with several challenges, such as reforming the annulus to maintain proper valve function and ensuring the correct position of the device within the CS over the long term. Not only the complexity of the implant and the procedure, but also the potential traumatic effects on the CS itself must be considered. Prior art devices generally do not have optimal performance in some of the aforementioned aspects of annuloplasty via the CS. The challenge is to reliably reform most of the annulus while providing a non-traumatic engagement with the anatomical structure. The prior art problem is a complex and difficult-to-operate device that may require frequent adjustment and repositioning to ensure accurate function over the long term. This can have an adverse impact on the patient and the healthcare system. The patient's risk increases. 【0004】 It is desirable to securely fix the implant, minimize the risk of damaging the CS, and simultaneously increase the degree of control over the reduction procedure, i.e., the reshaping of the valve annulus. 【0005】 Therefore, improved annuloplasty devices for annular reduction and reshaping are advantageous, particularly because they can reliably function over the long term, reduce the complexity of the procedure, and enhance patient safety by minimizing traumatic effects on anatomical structures. Furthermore, methods for reducing and reshaping the mitral annulus using such annuloplasty devices would also be advantageous. [Overview of the project] 【0006】 Therefore, embodiments of the present invention preferably aim to mitigate, alleviate, or eliminate one or more defects, shortcomings, or problems in the art as described above, by providing the apparatus according to the appended claims. [Means for solving the problem] 【0007】 According to a first embodiment, a valve repair device is provided for treating a defective mitral valve having an annulus, the annulus repair device being a removable, flexible, elongated displacement unit for temporary insertion into the coronary sinus (CS) adjacent to the mitral valve, the displacement unit having a delivery state for delivery into the CS and an operating state from which the displacement unit can be temporarily and reversibly transitioned, and a proximal reversibly expandable portion that can be reversibly folded into an expanded state for positioning against the tissue wall at the entrance to the CS, the displacement unit The stent comprises a proximal reversible expandable portion having a distal fixed portion that is movable in the longitudinal direction of the displacement unit relative to the proximal expandable portion, thereby correcting the shape of the valve ring to a modified shape when inserted into the CS, and a stent positioned around the displacement unit and movable longitudinally relative to the displacement unit for insertion into the CS, the stent being releasably connected to a delivery device and arranged radially (R) between the displacement unit and the proximal expandable portion, with the radial direction (R) being perpendicular to the longitudinal direction. 【0008】 A second aspect provides a method for treating a defective mitral valve having an annulus, the method comprising: inserting a removable, flexible, elongated displacement unit in a delivery state into the coronary sinus (CS) adjacent to the mitral valve; positioning a proximal reversible expandable portion with respect to the tissue wall at the entrance of the CS; fixing a distal fixation portion inside the CS; operating the displacement unit in an operational state, thereby moving the distal fixation portion in the longitudinal direction of the displacement unit, reducing the distance (L) between the distal fixation portion and the proximal expandable portion, and consequently correcting the shape of the annulus to a corrected shape; advancing a stent through the proximal expandable portion and across the displacement unit into the CS; fixing the stent inside the CS to maintain the corrected shape of the annulus; and withdrawing the displacement unit through the stent, thereby removing the displacement unit after it has been temporarily operated in an operational state. 【0009】 Other embodiments of the present invention are defined in the dependent claims, and features relating to the second and subsequent embodiments are applied mutatis mutandis to those relating to the first embodiment. 【0010】 Some embodiments of this disclosure enable the long-term function of a repaired mitral valve. 【0011】 Some embodiments of this disclosure provide a simplified mitral valve reduction procedure. 【0012】 Some embodiments of this disclosure achieve improved controllability in mitral valve reduction procedures. 【0013】 Some embodiments of this disclosure achieve a reduction in the risk of damaging anatomical structures such as CS. 【0014】 Some embodiments of this disclosure achieve reliable reduction while simultaneously reducing the risk of damaging anatomical structures such as CS. 【0015】 Some embodiments of this disclosure achieve improved mitral annulus reduction treatment while simultaneously providing reliable non-traumatic treatment. 【0016】 Some embodiments of this disclosure achieve a reduction in the risk of long-term adverse effects of CS implants. 【0017】 Where used herein, the term “equipped with / equipped with” is to be interpreted as specifying the presence of the described feature, integer, process, or component, but it should be emphasized that this does not exclude the presence or addition of one or more other features, integers, processes, components, or groups thereof. [Brief explanation of the drawing] 【0018】 These and other possible embodiments, features and advantages of the present invention will become apparent and clarified from the following description of embodiments of the present invention with reference to the accompanying drawings. [Figure 1] This is a schematic cross-sectional view of an annulus forming apparatus as an example. [Figure 2a] Schematic diagram of an annulus forming device according to one example. [Figure 2b] Schematic diagram of the annulus forming device of FIG. 2a in a state where the proximal portion is expanded, according to one example. [Figure 3a] FIGS. 3a - b are schematic diagrams of annulus forming devices with different lengths between the proximal expandable portion and the distal fixed portion, according to one example. [Figure 3b] FIGS. 3a - b are schematic diagrams of annulus forming devices with different lengths between the proximal expandable portion and the distal fixed portion, according to one example. [Figure 4a] Schematic diagram of an annulus forming device, according to one example, in which a catheter advances over an elongated displacement unit. [Figure 4b] Schematic diagram of the annulus forming device of FIG. 4a, according to one example, in which a stent advances over an elongated displacement unit. [Figure 4c] Schematic diagram of the annulus forming device of 4b, according to one example, in which a stent is exposed at a predetermined position on an elongated displacement unit. [Figure 4d] Schematic diagram of the annulus forming device of FIG. 4c, according to one example, in which an elongated displacement unit is pulled out through a stent. [Figure 4e] Schematic diagram of FIG. d in a cross - sectional view taken across the radial direction, according to one example. [Figure 5a] FIGS. 5a - b are schematic diagrams of an annulus forming device arranged in the coronary sinus (CS), according to one example, in which an elongated displacement unit is fixed using a proximal expandable portion and a distal fixed portion. [Figure 5b] FIGS. 5a - b are schematic diagrams of an annulus forming device arranged in the coronary sinus (CS), according to one example, in which an elongated displacement unit is fixed using a proximal expandable portion and a distal fixed portion. [Figure 5c] FIGS. 5c - d are schematic diagrams of an annulus forming device, according to one example, in which a catheter advances over an elongated displacement unit through a proximal expandable portion. [Figure 5d] FIGS. 5c - d are schematic diagrams of an annulus forming device, according to one example, in which a catheter advances through a proximal expandable portion and over an elongated displacement unit. [Figure 5e] Schematic diagram of an annuloplasty device in which a stent advances within the catheters of FIGS. 5c-d, according to one example. [Figure 5f] Schematic diagram of an annuloplasty device in which a stent advances within the catheters of FIGS. 5c-d, according to one example. [Figure 5g] Schematic diagram of an annuloplasty device in which the stent of FIGS. 5e-f is at least partially expanded within the CS, according to one example. [Figure 5h] Schematic diagram of an annuloplasty device in which the stent of FIGS. 5e-f is at least partially expanded within the CS, according to one example. [Figure 5i] Schematic diagram of an annuloplasty device in which the stent of FIGS. 5e-f is fully expanded within the CS, according to one example. [Figure 5j] Schematic diagram of an annuloplasty device in which the elongated displacement unit of FIG. 5i is drawn through the stent, according to one example. [Figure 5k] Schematic diagram of an annuloplasty device in which the stent of FIGS. 5e-f is fully expanded and embedded within the CS, according to one example. [Figure 5l] Schematic diagram of an annuloplasty device in which the stent of FIGS. 5e-f is fully expanded and embedded within the CS, according to one example. [Figure 6a] Schematic diagram of the mitral valve and adjacent coronary sinus. [Figure 6b] Schematic diagram of an annuloplasty device in which the stent of FIGS. 5e-f is fully expanded and embedded within the CS to reform the annulus, according to one example. [Figure 7] Schematic diagram showing, in cross-section, an annuloplasty device according to one example. [Figure 8a] Flowchart of a method for treating a defective mitral valve, according to one example. [Figure 8b] Flowchart of a method for treating a defective mitral valve, according to one example. 【DETAILED DESCRIPTION OF THE INVENTION】 【0019】 Specific embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention may be carried out in many different forms and should not be construed as being limited to the embodiments described herein. Rather, these embodiments are provided to make this disclosure thorough and complete and to fully convey the scope of the invention to those skilled in the art. The terms used in the detailed description of the embodiments shown in the accompanying drawings are not intended to limit the invention. In the drawings, similar numbers refer to similar elements. 【0020】 Figure 1 schematically shows an annuloplasty device (100) for treating a defective mitral valve with an annulus. The annuloplasty device (100) comprises a removable, flexible, elongated displacement unit (101) for temporary insertion into the coronary sinus (CS) adjacent to the mitral valve. The displacement unit (101) has a delivery state for delivery into the CS and an operating state from which the displacement unit can be temporarily and reversibly transitioned. The annuloplasty device (100) comprises a proximal reversible expandable portion (102). The proximal expandable portion (102) is reversibly foldable into an expanded state for positioning against the tissue wall at the entrance to the CS. Figures 2a and 2b illustrate an example of the proximal expandable portion (102) transitioning from the folded state in Figure 2a to the expanded state in Figure 2b. Figure 5a schematically shows how the proximal expandable portion (102) is positioned outside the CS to press against the wall at the entrance of the CS. The displacement unit (101) includes a distal fixed portion (103) that is movable relative to the proximal expandable portion (102) in the longitudinal direction (104) of the displacement unit (101) to the above operating state. Figure 5b schematically shows how the distal fixed portion (103) is fixed inside the CS. The distal fixed portion (103) may be fixed to the great cardiac vein. Figures 3a-3b show an example in which the distal fixed portion (103) is movable so that the distance between the proximal expandable portion (102) and the distal fixed portion (103) changes. This distance is reduced from a length shown by L in Figure 3a to a reduced length shown by L' in Figure 3b. When positioned inside the CS in the operating state, the annulus forming device (100) reshapes the annulus into a modified shape in which the annulus shrinks and the leaflets can join. Therefore, as illustrated in Figures 5a-5b, when the annulus forming device (100) is positioned inside the CS and the distal fixing portion (103) is fixed, the distal fixing portion (103) can be pulled out toward the proximal expandable portion (102) which applies counterforce against the tissue wall at the entrance of the CS. This allows the mitral valve annulus to be reshaped. 【0021】 Returning to Figure 1, the annulus forming device (100) includes a stent (105) positioned around the displacement unit (101) and movable along the longitudinal direction (104) relative to the displacement unit (101) for insertion into the CS. Figure 4B schematically shows how the stent (105) advances on the displacement unit (101) toward the distal fixation portion 103. Figures 5e-5f show the position of the stent (105) on the displacement unit (101) when the annulus forming device (100) is positioned inside the CS. The stent (105) can be expanded to fix inside the CS when the displacement unit (101) has reformed the annulus, as illustrated in Figures 5g-5i and further described below. The stent (105) is detachably connected to a delivery device (106), as schematically shown in Figures 4d and 5j, and can be separated within the CS to maintain the reformed annular shape after the displacement unit (101) is withdrawn, as shown in Figures 5j-5l and 6b. Figure 6a is a diagram of the heart showing the CS relative to the mitral valve (MV) in a top-down view. The CS is adjacent to the MV and curves around the annulus (A) of the MV. The stent (105) may have a releasable connection portion (114) to the delivery device (106), as illustrated in Figure 4d. The delivery device (106) may be configured to push or pull the stent (105) along the longitudinal direction (104) relative to the displacement unit (101). The stent (105) is positioned radially (R) between the displacement unit (101) and the proximal expandable portion (102), for example, as shown in Figure 1. The radial direction (R) is perpendicular to the longitudinal direction (104). By positioning the stent (105) between the displacement unit (101) and the proximal expandable portion (102), the proximal expandable portion (102) expands outside the CS, the displacement unit (101) becomes operational, and at the same time, the stent (105) can be advanced into the CS on the displacement unit (101). Therefore, by changing the length (L) using the displacement unit (101) before positioning the stent (105) inside the CS and finally fixing it, the reformation of the valve ring can be precisely controlled and optimized.Once the valve leaflets are properly joined and no regurgitation occurs, the stent (105) can be gradually expanded, for example, by observing the characteristics of blood flow and the movement of the valve leaflets, and by withdrawing the catheter (109) positioned over the stent (105), as further described below (Figures 5g-5i). The connection to the stent (105) can be maintained using the delivery device (106) even after the stent (105) has been fully expanded (Figure 5i). Subsequently, the force applied by the displacement unit (101) to the valve annulus can be gradually released, for example, by reducing the tension between the proximal expandable portion (102) and the distal fixed portion (103). The characteristics of blood flow and the movement of the valve leaflets can be continuously observed to ensure that no regurgitation occurs. The displacement unit (101) can be completely withdrawn through the stent (105) (Figure 5j), and the stent (105) can be separated if no regurgitation occurs (Figures 5k-l). Otherwise, the procedure can be repeated by, for example, advancing a catheter (109) over the stent (105) to capture the stent (105), using a displacement unit (101) to further adjust the reshaping of the valve annulus, and / or introducing another stent (105) of a different size onto the displacement unit (101) through the proximal expandable portion (102). 【0022】 The stent (105) may advance into the CS via the proximal expandable portion (102) on the displacement unit (101) before or after the displacement unit (101) reshapes its annulus (Figures 5e-5f). In either case, the stent (105) expands after the reshaping occurs and becomes fixed inside the CS. 【0023】 In this way, the annulus formation device (100) enables easy annulus formation via the CS. The reshaping of the annulus can be precisely controlled and optimized using the displacement unit (101), and the stent (105) can be fixed inside the CS to maintain the modified shape once appropriate valve function is confirmed. The safety of the procedure is improved because the displacement unit (101) in its operational state already produces a valve reduction effect, and at the same time, the position of the stent (105) relative to the displacement unit (101) and the CS can be changed and optimized. The above-described combination of the displacement unit (101) and the stent (105) eliminates the need to introduce a complex element, namely a stent, into the implant device to reduce the valve. Therefore, the stent (105) becomes more robust and less complex, thereby increasing its reliability in maintaining the desired valve function over the long term. In contrast, prior art implants may require repeated adjustments to reduce the annulus due to the complex interaction between multiple movable parts. Furthermore, as will be explained further below, the annular formation device 100 can be reduced by a non-traumatic displacement unit (101) instead of a stent (105) which may have a retaining unit (110), thereby reducing the risk of damaging the CS. Consequently, the risk of tearing tissue within the CS with such a retaining unit can be reduced. 【0024】 As described, the distance (L) between the proximal expandable portion (102) and the distal fixed portion (103) in the longitudinal direction (104) can be reduced to the reduced distance (L') when the displacement unit (101) transitions from the delivery state to the operating state. The proximal expandable portion (102) and the distal fixed portion (103) may be connected to different sheaths or wires, which may be independently movable in the longitudinal direction (104) to change the distance (L), as shown in Figures 3a-3b. 【0025】 The proximal expandable portion (102) is connected to the sheath (107) and can be configured to expand radially (R) perpendicular to the longitudinal direction (104) by pressing the proximal portion (108) of the sheath (107) toward the distal fixed portion (103), as shown in Figure 2b (see arrow near the sheath (107)). This facilitates the deployment of the expandable portion (102) into its expanded configuration. 【0026】 When the displacement unit (101) is positioned such that there is a distance (L') between the proximal expandable portion (102) and the distal fixed portion (103) that results in the desired reduction of the valve, the stent (105) is movable to a predetermined position on the displacement unit (101) in order to be positioned and fixed inside the CS. The annulus forming device (100) may include a catheter (109) that surrounds the stent (105) and positions the stent (105) longitudinally (104) relative to the displacement unit (101), as schematically shown in Figures 4a-4b and 5c-5f. Figure 4a shows an example in which the catheter (109) is first advanced on the displacement unit (101) before the delivery device (106) pushes the stent (105) forward within the catheter (109). However, it is also conceivable that the stent (105) be advanced on the displacement unit (101) simultaneously with the catheter (109). The stent (105) can be discharged from the catheter (109) by the aforementioned delivery device (106) and may also be recovered within the catheter (109). Figure 4c schematically shows the state in which the catheter (109) has been withdrawn and the stent (105) is exposed on the displacement unit (101). Figure 4d schematically shows the displacement unit (101) extended through the stent (105). The proximal expandable portion (102) is folded, allowing the stent (105) to be separated from the delivery device (106). 【0027】 Therefore, the catheter (109) may be movable longitudinally (104) within the sheath (107). In this way, the stent (105) can be positioned at a desired location on the displacement unit (101), while the proximal expandable portion (102) connected to the sheath (107) expands and is fixed at the entrance of the CS. 【0028】 Therefore, in the aforementioned operating state, the displacement unit may be able to move longitudinally (104) within the sheath (107). This enables effective and reliable positioning and deployment of the stent (105) within the CS while effectively controlling the amount of annular contraction by the displacement unit (101). 【0029】 The stent (105) may be reversibly expandable radially (R) in the operational state. Thus, once expanded, the stent (105) can be folded and removed again if necessary for repositioning or replacement, for example, as shown in the (partially) expanded state in Figure 5g. When removing, the stent (105) can be retracted into the catheter (109) by withdrawing the delivery device (106) from the catheter (109), thereby housing the stent (105) inside the catheter (109). The stent (105) may be self-expandable such that it expands in diameter when discharged from the catheter (109). In such a case, the stent (105) can be formed from a shape memory material that is heat-fixed to an expanded configuration with a diameter greater than the diameter of the CS. After being compressed and inserted into the catheter (105), the stent (105) is discharged into the CS, where it attempts to expand to its heat-fixed shape, thereby pressing against the tissue wall inside the CS. It is also conceivable that the stent (105) could be actively expanded, for example, by a balloon catheter that presses inside the stent (105), thereby increasing its diameter. 【0030】 The stent (105) may include a retaining unit (110) for fixing the stent (105) inside the CS, as schematically shown in Figures 4c-d, 5g-l, and 6b. Thus, when the displacement unit (101) shrinks from its length (L) to its reduced length (L'), thereby contracting the tissue surrounding the CS and reforming the valve annulus (Figures 3a-3b), the shape of the reformed tissue can be maintained by the stent (105) fixed within the tissue. Having the retaining unit (110) allows the stent (105) to be effectively and securely fixed within the tissue. The stent (105) may extend along most of the length of the CS, in a length that abuts the tissue wall of the CS without obstruction. This ensures that the reformed valve annulus can be reliably retained over a long period, especially when the retaining unit (110) extends substantially along the entire length of the stent (105). The length of the stent (105) may substantially correspond to the length of the CS, as schematically shown in Figures 5k-l. The retaining unit (110) may be provided along the length of the stent (105). This further ensures particularly reliable retention of the reshaped valve ring over a long period of time. 【0031】 The retaining unit (110) can be positioned on the surface portion (111) of the stent (105), which is configured to be positioned toward the annulus when the stent (105) is inside the CS, as schematically shown in the overhead view of Figure 6b in conjunction with Figure 4e, which shows a cross-section of the stent (105) in one example. Thus, the retaining unit (110) can be positioned in a defined circular sector (v) on the surface of the stent, as shown in Figure 4e. Positioning the retaining unit (110) toward the annulus allows for effective retention of tissue along the corresponding segment of the CS, ensuring that the shape of the modified annulus is maintained. In one example, the stent (105) may include at least one radiopaque marker (not shown). This makes it easier to orient the stent (105) relative to the direction of the valve annulus. 【0032】 In one example, multiple retaining units (110) may be arranged around the circumference of the stent (105). Therefore, the retaining units (110) can be arranged in multiple circular sectors (v) along the circumference of the stent (105). This may be advantageous in several applications where increased retention force is desired. 【0033】 The retaining unit (110) can be molded to penetrate the tissue within the CS, thereby imparting a retaining force to the tissue. The retaining unit (110) can be formed from the same material as the stent (105). Thus, the retaining unit (110) may be integrated with the stent (105). Therefore, the retaining unit (110) can be cut into individual elongated structures with penetrating tips within the structural configuration of the stent (105). By molding the retaining unit (110) as an integrated structure of the stent (105), a robust and high-strength retaining unit (110) is achieved, while minimizing the risk of dislocation or deformation over time. In this way, a strong and reliable fixation mechanism is achieved overall. The retaining unit (110) can be molded using different cutting techniques, such as laser cutting. 【0034】 The retaining unit (110) may be elastically transitionable from a contracted state to an expanded state. Therefore, the retaining unit (110) may be flexible enough to bend from an expanded state to a contracted state when placed in the catheter (109), and to expand from a contracted state to an expanded state when withdrawn from the catheter (109). This facilitates the delivery of the stent (105) via the catheter (109), and at the same time, allows for the expansion and fixation of the retaining unit (110) to the tissue when deployed from the containment state of the catheter (109). Thus, the retaining unit (110) can be heat-fixed to take on a predetermined expanded shape, for example, as shown in Figures 4d-e. Therefore, the expanded shape can correspond to a relaxed state in which the retaining unit (110) is not subjected to external force. Therefore, the retaining unit (110) may have a bias toward the expanded shape by moving toward a relaxed expanded state when withdrawn from the catheter (109). 【0035】 The retaining unit (110) can be aligned substantially coplanar with the outer diameter of the stent when contracted. This can reduce friction between the retaining unit (110) and the lumen of the catheter (109), thereby further facilitating the delivery of the stent (105) through the catheter (109). Furthermore, the smaller cross-section minimizes the risk of wear and damage to the catheter (109). 【0036】 In one example, the retaining unit (110) may include a shape memory material, and the operation of the shape memory material causes the retaining unit (110) to transition from a contracted state to an expanded state. For example, the shape memory material may be temperature-activated so that when heated to body temperature, the retaining unit (110) moves toward an expanded state. This enables advantageous deployment of the retaining unit (110) in several applications. 【0037】 The distal fixation portion (103) may include an expansion unit such as a balloon that is expandable radially (R). This enables efficient and non-traumatic fixation of the distal end of the displacement unit (101), and, together with the effective fixation of the proximal portion (102) to the wall of the CS, enables effective transfer of contractile forces between the proximal portion (102) and the distal portion (103). This enables effective modification of the radius of curvature of the CS and facilitates modification of the annulus shape. The annulus forming device (100) may include an expansion lumen (not shown) connected to the expansion unit and configured to deliver an expansion medium to the expansion unit. 【0038】 The length of the inflatable unit (103) can be adapted to various anatomical structures. The length of the inflatable unit (103) can be selected so as not to obstruct the blood vessels connecting to the CS when it is further fixed to the CS, for example, to the great cardiac vein / left coronary vein. The length of the inflatable unit (103) can also be made so as to be effectively fixed behind the curve or “corner” of the CS when moving to the great cardiac vein / left coronary vein. The length of the inflatable unit (103) may be sufficiently short to facilitate such fixation and to avoid slipping out of the curve or “corner” of the CS. 【0039】 The proximal expandable portion (102) may comprise an expandable chord or rib portion (112). The sheath (107) may be pressed toward the distal portion (114) attached to the end of the chord or rib portion (112). The compressive force between the distal portion (114) and the proximal portion (108) can thus press the chord (112) radially outward. However, the chord (112) may contain a shape memory material that tends to take on an expanded configuration in its relaxed state, and the chord (112) may be housed within an outer sheath that is pulled back to rejoin its expanded configuration. 【0040】 The presence of expandable chords (112) allows for flexible engagement with the tissue, eliminating sharp edges and twists, and further reducing the risk of tissue damage at the CS entry point. The chords (112) may also extend longitudinally (104), which facilitates engagement with symmetrical tissue walls and ensures even force transmission near the CS entry point, thus enabling firm fixation. Furthermore, the longitudinal extension of the chords (112) facilitates expansion of the chords (112) by applying a force longitudinally (104) to them. Multiple chords (112) may be arranged circumferentially so that forces are applied symmetrically and evenly around the tissue wall. 【0041】 The proximal expandable portion (102) may comprise an elongated rib portion (112) formed within the sheath (107) by an elongated slit (113) within the sheath (107), as schematically shown in Figure 2a. The rib portion (112) may be foldable to expand radially (R). This results in a simple and strong structure. Thus, the rib or chord portion (112) may be formed from the same material as the sheath (107). The aforementioned material may be non-traumatic to tissue and flexible and pliable. In the folded configuration seen in Figure 2a, the rib (112), i.e., the rib (112) that will soon expand, extends longitudinally (104), resulting in a compact radial profile. The rib or chord portion (112) may be equidistant around the circumference of the sheath (107). As revealed above, this allows for an even distribution of fixation force. 【0042】 The maximum expansion diameter (D) of the proximal expandable portion (102) may be at least three times the diameter of the CS. In some embodiments, the ratio of the maximum expansion diameter (D) of the proximal expandable portion (102) to the diameter of the CS is in the range of 3 to 5. In some embodiments, the aforementioned ratio may be in the range of 3.5 to 4.5, which provides particularly advantageous fixation of the proximal expandable portion (102) while maintaining a compact and easy-to-handle annular forming device (100). 【0043】 The valve ring forming device (100), as schematically shown in Figure 7, may include a guide wire (115) that extends within the lumen (116) of the displacement unit (101) and exits from the lumen (116) at the distal opening (117) of the displacement unit (101). The guide wire (115) may be inserted into the CS, and the displacement unit (101) can then advance along the guide wire (115) to position itself within the CS. This facilitates the positioning of the displacement unit (101). 【0044】 Figure 8a shows a method (400) for treating a defective mitral valve. The order in which the steps of method (400) are shown should not be interpreted restrictively, and the order in which the steps of method (400) are performed is considered to be changeable. Method (400) includes the steps of: inserting a removable, flexible, elongated displacement unit (101) in a delivery state into the coronary sinus (CS) adjacent to the valve (401); positioning the proximal reversible expandable portion (102) relative to the tissue wall at the entrance of the CS (402) (Figure 5a); fixing the distal fixation portion (103) inside the CS (403) (Figure 5b); and operating the displacement unit (404) to an operating state in which the distal fixation portion is moved longitudinally (104) of the displacement unit so as to modify the shape of the valve annulus to a corrected shape, thereby reducing the distance (L) between the distal fixation portion and the proximal expandable portion. Method (400) further includes the steps of advancing the stent (105) into the CS on the displacement unit through the proximal expandable portion (405) (Figures 5e-5f), fixing the stent inside the CS to maintain the modified shape of the valve annulus (406) (Figures 5g-5i), and withdrawing the displacement unit (101) through the stent (407), temporarily operating it in the operational state, and then removing it (408) (Figures 5j-l, 6b). Thus, Method (400) provides the advantages described above in relation to the annulus forming device (100) and Figures 1-7. Method (400) provides an improved annulus forming procedure that securely fixes the stent (105) and increases the degree of control over the reduction procedure while minimizing the risk of damaging the CS. As the proximal expandable portion (102) expands outside the CS and the displacement unit (101) is in operation, the stent (105) is advanced by the displacement unit (101), ensuring that the stent (105) is reliably positioned and fixed while the valve has already been reformed by the displacement unit (101). In this way, a particularly robust and reliable valve ring formation procedure is achieved. 【0045】 Figure 6b shows an alternative flowchart of method (400) for treating a defective mitral valve. The order in which the steps of method (400) are shown should not be interpreted restrictively, and the order in which the steps of method (400) are performed is considered to be changeable. 【0046】 The distal fixation portion (103) may include an inflatable unit, also indicated by reference no. (103). Fixing the distal fixation portion (103) may include inflating the inflatable unit within the coronary sinus of the heart, and / or within the great cardiac vein, and / or within the anterior interventricular branch or anterior interventricular vein, and / or within the posterior vein and / or posterior ventricular vein (4031). 【0047】 The proximal expandable portion (102) can be connected to the sheath (107). Positioning the proximal expandable portion (102) may include pressing the proximal portion (108) of the sheath (107) toward the distal fixed portion (103) to expand the proximal expandable portion radially (R) (4021). 【0048】 Fixing the stent (105) may include withdrawing the catheter (109) surrounding the stent (105) (4061) and expanding the stent (105) in a radial direction (R) perpendicular to the longitudinal direction (104) (4062), as schematically shown in Figures 5g to h. 【0049】 The catheter (109) may be movable longitudinally (104) on the displacement unit (101) through the proximal expandable portion (102), resulting in the advantageous effects described above. 【0050】 Fixing the stent (105) may include fixing the retaining unit (110) of the stent (105) to the CS (4063) in order to maintain the modified shape of the valve ring when the displacement unit (101) is withdrawn, as schematically shown in Figures 5g to l. 【0051】 Fixing the retaining unit (110) may include fixing the retaining unit (110) in the direction of the annulus within the tissue wall of the CS (4064). 【0052】 The method (400) may include advancing a catheter (109) over the stent (105) to remove the stent (105) from the CS (4065) in order to reposition the stent (105) or remove it from the CS. 【0053】 Fixing the stent (105) may include separating the stent (105) from the delivery device (106) which is movably positioned within the catheter (109) (4066) (Figure 5k). 【0054】 The present invention has been described above with respect to specific embodiments. However, embodiments other than those described above are also possible within the scope of the invention. Different features and processes of the invention may be combined in combinations other than those described. The scope of the invention is limited only by the appended claims. 【0055】 Furthermore, it will be readily apparent to those skilled in the art that all parameters, dimensions, materials, and configurations described herein are intended to be illustrative, and that actual parameters, dimensions, materials, and / or configurations will depend on the specific application / application in which the teachings of the present invention are used.

Claims

[Claim 1] An annular formation device (100) for treating a defective mitral valve having an annular, A removable, flexible, elongated displacement unit for temporary insertion into the coronary sinus (CS) adjacent to the mitral valve, wherein the displacement unit (101) has a delivery state for delivery into the CS and an operating state from which the displacement unit can temporarily and reversibly transition. A proximal reversibly expandable portion that can be reversibly folded into an expanded state for positioning relative to the tissue wall at the entrance of the CS, The displacement unit comprises a proximal reversible expandable portion (102) and a distal fixed portion (103) that is movable in the longitudinal direction (104) of the displacement unit relative to the proximal reversible expandable portion, such that when the displacement unit is inserted into the CS, the shape of the valve ring is modified to the modified shape, A stent positioned around the displacement unit and movable along the longitudinal direction relative to the displacement unit for insertion into the CS, The stent is detachably connected to the delivery device (106) and is arranged radially (R) between the displacement unit and the proximal reversibly expandable portion, with the radial direction (R) being perpendicular to the longitudinal direction, and the stent (105) and Equipped with, The proximal reversible expandable portion is connected to a sheath (107) and is configured to expand radially (R) by pressing the proximal portion (108) of the sheath toward the distal fixed portion. The valve ring forming device includes a catheter (109) that surrounds the stent and positions the stent in the longitudinal direction relative to the displacement unit, and the stent is dischargeable from the catheter by the delivery device and recoverable within the catheter. The catheter is a valve ring forming device that, in the operating state, is movable on the displacement unit and inside the sheath in the longitudinal direction. [Claim 2] The valve ring forming apparatus according to claim 1, wherein the stent is reversibly expandable in the radial direction (R) in the operating state. [Claim 3] The valve ring forming apparatus according to claim 1 or 2, wherein the stent is provided with a holding unit (110) for fixing the stent inside the CS. [Claim 4] The valve ring forming apparatus according to claim 3, wherein the retaining unit is positioned on a defined surface portion (111) of the stent, which is adapted to be positioned toward the valve ring when the stent is inside the CS. [Claim 5] The valve ring forming apparatus according to claim 3, wherein a plurality of retaining units are arranged around the circumference of the stent. [Claim 6] The retaining unit is elastically capable of transitioning from a contracted state to an expanded state, thereby the retaining unit, When placed inside the catheter, it curves from the expanded state to the contracted state, and When removed from the catheter, it expands from the contracted state to the expanded state. A valve ring forming apparatus according to any one of claims 3 to 5, having such flexibility. [Claim 7] The valve ring forming apparatus according to claim 6, wherein the retaining unit is positioned substantially on the same plane as the outer diameter of the stent in the contracted state. [Claim 8] The valve ring forming apparatus according to any one of claims 1 to 7, wherein the longitudinal distance (L) between the proximal reversibly expandable portion and the distal fixed portion is reduced to a reduced distance (L') when the displacement unit transitions from the delivery state to the operating state. [Claim 9] The valve ring forming apparatus according to any one of claims 1 to 8, wherein the proximal reversibly expandable portion comprises an elongated rib portion (112) formed within the sheath (107) by an elongated slit (113) within the sheath and extending in the longitudinal direction, and the rib portion is foldable to expand in the radial direction (R). [Claim 10] The valve ring forming apparatus according to any one of claims 1 to 9, wherein the distal fixed portion comprises an expansion unit that can be expanded in the radial direction (R). [Claim 11] The valve ring forming apparatus according to any one of claims 1 to 10, further comprising a guide wire (115) that extends within the lumen (116) of the displacement unit and is positioned to exit the lumen at the distal opening (117) of the displacement unit.

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