STENT DEVICE FOR A PROSTHETIC HEART VALVE

Abstract

Replacing a defective atrioventricular heart valve, in particular a tricuspid valve, may include stent devices, prosthetic heart valves, delivery systems, and corresponding methods, which provide an improved fixation without distortion of the native anatomy. A stent device for a prosthetic heart valve has an axially extending mesh-shaped body, configured to fit an orifice and defining an inner channel as a passageway from a proximal to a distal end. At least three outer support arms extend from the distal end of the body towards the proximal end. Each support arm has a distal end first support region and a proximal end second support region. The second support region extends radially outwards in the deployed state. Each support arm has a flexible region between the first and second support regions, which is formed as an axially tapered section of the support arm and/or each support arm is tapered towards the proximal end.

Claims

1. Stent device (10) for a prosthetic heart valve, comprising: a mesh-shaped body (12) extending in an axial direction, said body (12) being configured to fit an orifice and defining an inner channel (15) for providing a passageway from a proximal end (16) to a distal end (17) of the body (12), and at least three outer support arms (18) extending from the body (12) from the distal end (17) of the body (12) towards the proximal end (16), each support arm (18) comprising a first support region (20) at the distal end (1 7), and a second support region (22) at the proximal end (16), wherein the second support region (22) extends radially outwards in the deployed state, wherein each support arm (18) comprises a flexible region (24) between the first support region (20) and the second support region (22), which is formed as a tapered section of the support arm (18) in an axial direction, and/or wherein each support arm (18) is tapered towards the proximal end (16).

2. Stent device (10) according to claim 1, wherein the body (12) is configured to fit an annulus (26) of the heart valve, wherein the flexible region (24) is adapted to conform to the annulus (26), the first support region (20) is adapted to conform to the ventricular portion (28) of the annulus (26), and/or the second support region (22) is adapted to conform to the atrial portion (30) of the annulus (26).

3. Stent device (10) according to any of the preceding claims, wherein the body (12) comprises an essentially tubular or cylindrical shape.

4. Stent device (10) according to any of the preceding claims, wherein each support arm (18) is formed as a closed loop.

5. Stent device (10) according to claim 4, wherein the closed loop extends beyond the proximal end (16) of the body (12) and/or comprises a rounded and/or tapered proximal end.

6. Stent device (10) according to claim 4 or 5, wherein the closed loop defines a profile having a convex portion (32) and a concave portion (34) in a longitudinal section of the support arm (18) and wherein the convex portion (32) defines the first support region (20), wherein the concave portion (34) is preferably adjacent to the convex portion (32).

7. Stent device (10) according to claim 6, wherein each support arm (18) comprises the flexible region (24) between the first support region (20) and the second support region (22) and wherein the concave portion (34) defines the flexible region (34).

8. Stent device (10) according to claim 6 or 7, wherein a radial extension of a radially outermost point of the convex portion (32) is larger than a radially innermost point of the concave portion (34) and/or wherein a radially outermost point of the convex portion (32) lies between a radially innermost point of the concave portion (34) and a proximal tip of the second support region (22).

9. Stent device (10) according to any of claims 6 to 8, wherein the profile is formed as an inverted S-shape, sine wave shape, N-shape, or M-shape in an axial direction and/or in a radial direction.

10. Stent device (10) according to any of the preceding claims, wherein each support arm (18) is linked to the body (12) via at least one linking arm (36) formed by a curvature of the first support region (20).

11. Stent device (10) according to claim 10, wherein each support arm (18) is linked to the body (10) via two linking arms (36).

12. Stent device (10) according to claim 10 or 11, wherein the curvature comprises an angle of more than 90° and/or defines a rounded shoulder, said shoulder preferably having a distal radius (46) and a proximal radius, wherein the distal radius (46) is larger than the proximal radius (48).

13. Stent device (10) according to any of the preceding claims, comprising an uneven number of support arms (18), preferably 5, 7, or 9 support arms (18), or a multitude/multiple of two and/or three support arms (18), said support arms (18) being adapted to a tricuspid valve or mitral valve.

14. Stent device (10) according to claim 13, comprising six support arms (18) and being configured for a tricuspid valve.

15. Stent device (10) according to any of the preceding claims, wherein the circumferential spacing between the support arms (18) is asymmetric or symmetric and/or is adapted to a tricuspid valve or mitral valve.

16. Stent device (10) according to any of the preceding claims, wherein the mesh shape of the body (12) comprises a droplet shape, a diamond shape, or an essentially oval shape.

17. Stent device (10) according to any of the preceding claims, wherein the mesh-shape of the body (12) is formed by a lattice of a plurality of diamond-shaped cells (14) that are directly connected to each other or are connected via struts (13), said cells (14) preferably being essentially equal in size and/or shape.

18. Stent device (10) according to any of the preceding claims, wherein a portion (38) of the proximal end (16) of the body (12) extends radially outwards.

19. Stent device (10) according to claim 18, wherein the portion (38) of the proximal end (16) of the body (12) extends between 70° and 110° with regard to the axial direction of the body (12).

20. Stent device (10) according to claim 18 or 19, wherein the portion (38) is defined by a plurality of second closed loops, which are preferably arranged in a circumferentially staggered formation with regard to the support arms (18) arranged at the distal end (17).

21. Stent device (10) according to claim 20, wherein the portion (38) comprises at least one eyelet (44) for securing the stent device (10) to a delivery system, preferably at least two eyelets (44), each of the at least one eyelet(s) (44) being arranged at a respective second closed loop, preferably at every second or third second closed loop and/or at the proximal end (16) or radially outermost end of the second closed loop.

22. Stent device (10) according to any of the preceding claims, wherein the body (12) and the plurality of support arms (18) are formed as a single piece and/or as a wire frame.

23. Stent device (10) according to any of the preceding claims, wherein the body (12) or the passageway defined by the body (12) comprises an inner diameter between 29 mm and 36 mm, preferably about 30 mm or about 35 mm.

24. Stent device (10) according to any of the preceding claims, wherein at least the second support region (22) of the supporting arms (18) and/or the proximal end (16) of the outer body (12) are covered with a foil of a liquid impermeable or semi-impermeable material so as to form a cuff between the support arms (18) and the body (12) and/or between the support arms (18).

25. Stent device (10) according to any of the preceding claims, wherein the body (12) comprises at least two or at least three fixation means or windows (40) for receiving a valve assembly or wherein the cells of the mesh-shaped body (12) are configured for receiving and fixation of a valve assembly.

26. Prosthetic heart valve, comprising a stent device (10) according to any of the preceding claims and a valve assembly arranged within the inner channel (15) and/or at a proximal (16) or distal end (17) of the body (12) and being secured to the body (12) by means of fixation means or windows (40) or direct fixation to one or more cells of the mesh-shaped body (12).

27. Prosthetic heart valve according to claim 26 configured for replacing a tricuspid valve or a mitral valve.

28. Delivery system, comprising the stent device according to any of the preceding claims in a collapsed state.

29. Method for replacing a tricuspid valve or mitral valve, comprising the steps of: providing a stent device according to any of the claims 1-25 in a collapsed state in a delivery system, percutaneously introducing the stent device into a tricuspid valve or mitral valve region of a patient via said delivery system, such that the distal end of the body is at a ventricular portion and the proximal end of the body is at an atrial portion and the body and support arms straddle the annulus, and deploying the stent device by expanding the stent device, such that the flexible region conforms to the annulus and the second support region of the outer support arms conform to the atrial side.

30. Method of producing a stent device according to any of the claims 1-25, comprising the steps of: laser cutting the body and support arms from a metallic memory material; heat forming the body and support arms, so as to provide a predefined shape of the body and support arms; and collapsing the body and support arms.

31. Method according to claim 30, wherein the stent device is made from a single piece.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0090] The present disclosure will be more readily appreciated by reference to the following detailed description when being considered in connection with the accompanying drawings in which:

[0091] FIG. 1 is a graphical representation of a prior art embodiment of a prosthetic heart valve at a ventricular portion of the tricuspid valve;

[0092] FIG. 2 is a graphical representation of a stent device according to the invention deployed around the anatomical structure of the tricuspid valve;

[0093] FIGS. 3A-3D are schematic representations of stent devices according to the invention after laser cutting and prior to heat forming;

[0094] FIGS. 4A and 4B are perspective views of a stent device according to the invention in an expanded state;

[0095] FIG. 5 is a schematic perspective view of a stent device according to the invention having an alternative proximal end of the body;

[0096] FIG. 6 is a schematic side view of the stent device according to FIG. 5;

[0097] FIG. 7 is a schematic representation of a stent device according to the invention having an alternative proximal end of the body comprising second closed loops;

[0098] FIG. 8 is a schematic representation of a staggering formation of the proximal end of the stent device according to FIG. 7;

[0099] FIGS. 9A to 9C depict different views of a staggering formation according to FIG. 7 with alternative second closed loops;

[0100] FIG. 10 is a schematic representation of a stent device according to the invention after laser cutting and prior to heat forming having eyelets; and

[0101] FIGS. 11A and 11B depict different views of a stent device according to the invention with an alternative support arm configuration.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0102] In the following, the invention will be explained in more detail with reference to the accompanying figures. In the Figures, corresponding elements are denoted by identical reference numerals and repeated description thereof may be omitted in order to avoid redundancies.

[0103] In FIG. 1 a graphical representation of a prior art embodiment of a prosthetic heart valve positioned within a tricuspid valve is shown. Accordingly, a prosthetic heart valve is positioned within the tricuspid valve by means of a delivery system 42, e.g. a catheter or sheath. The prosthetic heart valve is positioned such that the body 12 or framework of the prosthetic heart valve is oriented in a longitudinal direction from a proximal end 16 to a distal end 17 of the tricuspid valve. Accordingly, upon deployment or expansion of the prosthetic heart valve, the support arms 18 of the prosthetic heart valve grasp the leaflets 27 of the tricuspid valve, thereby forming ventricular stabilizers. The support arms 18 are hence arranged at the ventricular side 28 of the tricuspid valve and are configured to provide a stabilization of the leaflets 27. After deployment of the prosthetic heart valve, the body 12 or framework of the prosthetic heart valve extends towards the proximal end 16, wherein the body 12 is formed as a flexible mesh body to conform to the anatomical structure of the leaflet 27 and to exert a radially outward force towards the leaflet 27, such that the prosthetic heart valve is held by the leaflets 27 while neither the support arms 18 nor the body 12 are actually in contact with the ventricular portion 28 or the atrial portion 30 of the annulus.

[0104] An embodiment of the stent device 10 according to the invention is depicted in FIG. 2 in a graphical representation, wherein the stent device 10 is deployed around the anatomical structure of the tricuspid valve corresponding to the anatomical structure according to FIG. 1. The stent device 10 is depicted in an expanded or deployed state, wherein a longitudinal axis of the stent device 10 and the body 12 is oriented along an axis defined by the proximal end 16 and the distal end 17 of the tricuspid valve. The body 12 is comprised of a mesh-shaped wiring made of nitinol and is formed as an essentially tubular body 12 having a cylindrical or circular shape.

[0105] A plurality of support arms 18 extend from the distal end 17 of the body 12. Although the sectional view depicts only two support arms 18, three or more, preferably six, nine, or twelve support arms 18 may be realized along a circumference of the distal end 17 of the body 12, e.g. at equidistant spacings or formed so as to be adjacently arranged to each other. The support arms 18 extend towards the proximal end 16 of the body 12 along an outer surface of the body 12. The inner surface is defined by an inner channel (not shown), which establishes a passageway for a blood flow from the proximal end 16 to the distal end 17, i.e. from the right atrium to the right ventricle of the heart during a systolic phase of the heart.

[0106] The support arms 18 furthermore comprise an S-shape or inverted S-shape in the longitudinal section of the stent device 10 and hence extend radially outwardly and inwardly along the longitudinal axis. Thereby, the support arms 18 define a first support region at the distal end 17 and a second support region at the proximal end 16, wherein the second support region extends radially outwardly at the proximal end 16 due to a deflection provided by a flexible region arranged between the first and second support region.

[0107] Accordingly, the shape of the support arms 18 and, in particular, the support regions allow the support arms 18 to conform to the ventricular portion 28 and the atrial portion 30 of the annulus 26. Furthermore, the flexible region is adapted to conform to the annulus 26 of the tricuspid valve. Thereby, the support arms 18 ensure that the stent device 10 is supported at opposing sides of the tricuspid valve and is fitted to the annulus 26 of the tricuspid valve, such that the stent device 10 is biased into the tricuspid valve region and in particular into the annulus 26 thereof.

[0108] Hence, the configuration of the support arms 18 allows the stent device 10 to be preferably secured to the annulus 26 without requiring invasive techniques such as sewing or stitching and without any clamping or grasping force or without exerting a radially outward force that potentially disrupts remaining anatomical landmarks and tissue. Instead, such configuration enables that the function of the body 12 of the stent device 10 is decoupled from the function of the support arms, such that the body 12 may be rigid, thus providing a stabile supporting structure or framework for e.g. a valve assembly.

[0109] FIG. 3A is a schematic representation of a stent device, e.g. as depicted in the embodiment according to FIG. 2, wherein the stent device is depicted after laser cutting and prior to a heat forming process. On the left hand side, i.e. at the proximal end 16 of the stent device, the body 12 is depicted formed as a mesh shape. Said mesh is depicted to comprise two connected cells 14 arranged adjacently along the longitudinal axis of the stent device. The body 12 hence comprises a plurality of cells 14, which may be formed, e.g. by means of heat forming to a tubular or oval shaped structure so as to form a cylindrical shape defining an inner channel configured as a passageway for a blood flow.

[0110] Furthermore, the body 12 comprises three fixation means or windows 40, which are arranged at the distal end 17 of the body 12, wherein said windows 40 are formed by three corresponding struts 13 extending in the longitudinal direction. Accordingly, when the body 12 is formed into its predefined shape, the windows 40 are arranged in a circumferential manner at essentially equal spacing to each other. The windows 40 may e.g. be used to attach a valve assembly, e.g. synthetic or processed native cusps or leaflets to provide a required valve function adapted to the patient.

[0111] Although the windows 40 are depicted at the distal end 17 of the body 12, said windows 40 may also be provided at corresponding struts 13 at the proximal end 16 and the spacings between said windows 40 may vary. By the same token, the stent device preferably comprises at least three windows 40, e.g. for fixation of at least three cusps, e.g. for a tricuspid valve, but may also comprise more than three windows 40, so as to provide a physician or surgeon with more fixation possibilities.

[0112] According to the embodiment of FIG. 3A, the stent device furthermore comprises six support arms 18 extending from the distal end 17 of the body 12. After heat forming into a predefined shape, said support arms 18 extend towards the proximal end 16 at an outer surface of the body 12 and define two support regions and a flexible region, as described in view of FIG. 2 in the above. The support arms 18 are furthermore provided as closed loops, which are each linked to the body 12 via two linking arms, such that the structural and mechanical stability of the support arms 18 is increased. Furthermore, the support arms 18 comprise an essentially petal shape and which comprise a rounded proximal end after heat forming. Thereby, the support arms 18 provide an improved supporting function due to the increased contact area while the rounded proximal ends ensure that sharp edges and potential tissue damage are avoided and a risk of breakage of the proximal ends is reduced.

[0113] FIGS. 3B to 3D depict an alternative embodiment, wherein the proximal end 16 comprises second closed loops 38, which are arranged in a staggered formation with regard to the support arms 18. The proximal end 16 of the second closed loops may comprise a reinforcement formed by a thicker region to increase the linking strength between the legs of the second closed loops 38, as indicated on the left hand side of FIGS. 3B and 3D. The second closed loops 38 may be heat formed into e.g. a flaring shape, such that the second closed loops 38 extend radially outwardly, as explained in further detail in view of FIGS. 5 to 9 below.

[0114] Prior to heat forming, the stent device comprises an essentially flat shape extending in a longitudinal direction, as depicted by FIG. 3C. The stent device may be coiled along the longitudinal axis to form an essentially cylindrical body 12 with second closed loops 38 extending from the proximal end and support arms 18 extending from the distal end, as shown in FIG. 3D. Thereby, the body 12 of the stent device is given further structural stability and may be easily brought in its ultimate shape by heat forming the support arms 18 and second closed loops 38.

[0115] The embodiment according to FIG. 4A essentially corresponds to the embodiments according to FIGS. 2 and 3 and depict the stent device 10 after heat forming and in an expanded state. Accordingly, the stent device 10 also comprises a total of six support arms 18, formed as closed loops which extend from the distal end 17 of the body 12 via with two linking arms 36. As described in view of FIG. 2, the support arms 18 comprise a profile in the longitudinal section comprising an essentially inverted S-shape or sigmoidal shape, which are defined by a first support region 20 at the distal end 17, a second support region 22 at the proximal end 16 and a flexible region 24 therebetween. Said flexible region 24 is formed as a tapered section, e.g. formed by a constriction along the longitudinal axis of the stent device 10 so as to allow a deflection of the second support region 22.

[0116] The first support region 20 of each support arm 18 is formed as a convex portion 32, which at least in part defines a curvature forming each of the linking arms 36. The curvature ensures that the extension into the ventricular portion of the valve may be reduced, such that the blood flow is not disrupted and the stent device 10 is not brought in contact with any myocardial areas, which should not be contacted by the implanted stent device 10. The flexible region 24 is arranged around an infliction point of the convex portion 32 and is configured as a concave portion 34, extending into the second support region 22, which extends radially outwardly.

[0117] The convex portion 32, the concave portion 34, and the radially outwardly extending second support region 22 are thereby adapted to support a ventricular portion, an annulus portion, and an atrial portion of the tricuspid valve, respectively, such that each region provides an essentially matching geometry. The stent device 10 may hence be biased into the annulus of the tricuspid valve without invasively engaging or compressing the respective anatomical structures. Thus, disruption of the remaining anatomical structures may be effectively avoided.

[0118] Furthermore, the inner channel 15 is depicted in the embodiment according to FIG. 4A, which is defined by the mesh-shaped body 12 of the stent device 10. Accordingly, both the body 12 and the inner channel 15 comprise an essentially tubular and cylindrical shape, wherein the rigidity and size and dimensioning of the body 12 ensures that a maximum inner channel volume is provided so as to maximize the blood flow from the proximal end 16 to the distal end 17. The mesh body 12 is furthermore comprised of a plurality of cells 14 and corresponding struts 13, wherein the cells 14 comprise a droplet shape without sharp edges between adjacent cells 14, so as to further improve the structural integrity of the body 12.

[0119] When the stent device is in its deployed state, a gap may be formed between the outer surface of the body 12 and the support arms 18, as shown in the top view of FIG. 4B at the proximal end 16. Accordingly, the body 12 preferably exerts no radially outward force on the anatomical structures of the annulus and is only held on one side of the body 12 by the support arms 18, which may adapt both to the ventricular portion and the atrial portion so as to bias the stent device within the annulus. Due to the gap maximal flexibility and adaptability is ensured for the support arms 18 while at the same time ensuring that the anatomical shape is not deteriorated or compromised by the body 12 of the stent device.

[0120] An alternative configuration of the proximal end 16 of the body 12 is depicted in a schematic perspective view according to the embodiment of FIG. 5, wherein the stent device 10 comprises a body 12 having an alternative proximal end portion 38 of the body 12 extending in a radially outward direction, i.e. forming a flaring surface. Accordingly, the supporting arms 18, which extend from the distal end 17 of the body 12 towards the proximal end 16 of the body 12 may be brought into proximity or into contact with the proximal end portion 38 of the body 12.

[0121] For example, the support arms 18, which comprise, in addition to a first support region 20 at the distal end 17 and an adjacent flexible region 24, a second support region 22 at the proximal end 16, may deflect radially outwardly at the second support region 22 so as to be in contact with the radially outwardly extending proximal end portion 38. Thereby, the proximal end portion 38 may not only improve the sealing of the stent device 10, but may simultaneously facilitate the blood flow and/or an insertion into the inner channel of the body 12, e.g. by choosing an angle with regard to the longitudinal axis of the stent device 12 to define a chamfer. In addition, such arrangement may further increase the support of the stent device 10, by an additional surface that may be aligned with the corresponding atrial portion of the annulus or valve and to provide an additional supporting feature, should the second support region 22 not have the desired effect.

[0122] The embodiment according to FIG. 5 is furthermore schematically depicted in a side view according to FIG. 6. Here, the radially outwardly extending proximal end region of the body 12, is slightly tilted towards the outer surface of the body 12 and the support arms 18, e.g. at an angle between 70° and 90°. Such angle may e.g. be chosen to conform to the atrial portion of the annulus and may furthermore ensure an optimal sealing towards the proximal end 16 of the support arms 18. It is to be understood that other angles are possible and that the shape of the proximal end portion 38 is not restricted to the shape depicted in FIGS. 5 and 7, but may also comprise shapes corresponding e.g. to the mesh shape of the body 12.

[0123] Accordingly, in an exemplary embodiment, the stent device may comprise a proximal end portion 38 of the body comprising a plurality of second closed loops, as schematically depicted in FIG. 7. Said second closed loops are hence formed as extensions from the proximal end of the body, i.e. extensions from the mesh shape of the body, such that said second closed loops are connected to two adjacent cells 14 at the proximal end of the body. As indicated by the dashed line, the proximal end portion 38 that is extended radially outward, i.e. flares in a direction essentially perpendicular to the longitudinal axis of the stent device, comprises a portion of the last row of struts 13 of each of the last cells 14 at the proximal end of the body.

[0124] For example, the radially outward extending portion may comprise between ¼ and ½ of the last row of struts 13. In the embodiment according to FIG. 7, said portion comprises about ⅓ of the length of the last or ultimate row of struts 13 in the longitudinal direction of the stent device. Accordingly, depending on the anatomical structure corresponding to the pathophysiological condition of the patient, the second closed loops and the proximal end portion 38 may be at equal size with or sized smaller than the second support regions of each of the support arms.

[0125] The proximal end portion 38 may furthermore be arranged at a staggering formation in view of the proximal end of the second support regions 22 of the plurality of support arms, as schematically depicted in the embodiment according to FIG. 8. Accordingly, the proximal end portion 38 may comprise a plurality of second closed loops extending from the proximal end of the body, e.g. as described in view of FIG. 7, which are deflected radially outwardly and are arranged between the second support regions 22 of each pair of adjacent support arms. Accordingly, the stent device may comprise a total of six support arms with corresponding second support regions 22 and a total of six second closed loops defined by the proximal end portion 38, which alternate each other in a circumferential manner along the circumference of the body 12 of the stent device. Also shown is the inner channel 15, which is hence not obstructed by the second support regions 22 and the proximal end portion 38. While the tips of the support regions 22 may be in the form of a triangle forming an acute angle at the end region, a rounded tip (not depicted by FIG. 8) may be more preferred.

[0126] Alternatively, the proximal end portion 38 may be provided in an alternative staggering configuration, e.g. when the number of second closed loops and the number of support arms do not match. For example, the proximal end portion 38 may comprise only three second closed loops, such that the second closed loops are arranged only between every second pair of adjacent second support regions 22. By the same token, the proximal end portion 38 may comprise a larger number of second closed loops, which are dimensioned smaller than the second support regions 22 of the support arms, such that e.g. two second closed loops are arranged between each pair of adjacent second support regions 22. It will be obvious to a person skilled in the art that the above number of second closed loops and second support regions 22 are for illustrative purposes only and are not limiting to the embodiments. In other words, other arrangements having a higher number of support arms or having a number between three and six support arms are possible and within the scope of the embodiments.

[0127] In the embodiment depicted in FIGS. 9A to 9C an alternative staggering formation of second closed loops 38 and support arms 18 is shown, wherein the second closed loops 38 are dimensioned such that they are similar to the closed loops of the support arms 18. Accordingly, as e.g. shown in FIG. 9A in the schematic top view (left) and perspective top view (right), the second closed loops 38 extend radially outwardly and may comprise a sectional surface area that is similar to the sectional surface area of the support arms 18. That holds, even though the second support region 22 of the support arms 18 may extend further radially outwardly, as also shown in FIGS. 9B and 9C, which represent a side view and a perspective view of the embodiment, respectively.

[0128] Furthermore, FIGS. 9B and 9C show a gap, which may occur between the support arms 18 and the body 12 of the stent device, in analogy to the embodiment according to FIG. 4B. Thereby, a tolerance is ensured between the support arms 18 and the body 12. Resilience of the support arms 18 is thus increased. In other words, as shown e.g. in FIG. 9B, the gap between the S-shape of the support arms 18, i.e. the convex and concave region in the longitudinal section, and the body 12 of the stent device may vary at least partially or sectionwise, so as to accommodate the stent device in the annulus, thereby adapting its to the anatomical structure thereof.

[0129] In addition, the flaring second closed loops 38 ensure that a direct contact between the body 12 and the anatomical structure may be avoided, such that the body 12 does not exert a radially outwardly directed force on the annulus. Potentially adverse forces that are detrimental for the remaining anatomical landscape are reduced or avoided. However, the flaring arrangement ensures that a fluid flow from the proximal end to the distal end is not significantly impaired. Furthermore, as indicated in FIG. 9C, the proximal end 16 and the distal end 17 are inverted. Such flaring of the second closed loops facilitates the insertion of e.g. a valve assembly into the body 12 by forming a chamfering surface.

[0130] In FIG. 10 a schematic representation of a stent device 10 according to the invention after laser cutting and prior to heat forming is shown as an alternative to the embodiment depicted in FIG. 3B. In this embodiment, eyelets 44 are provided on a proximal end 16 or proximal tip end of the second loops 38 of the stent body 12, which enable that the stent device 10 may be secured to a delivery system for insertion into the anatomic region of interest. Accordingly, said eyelets 44 may also be used after insertion for release and final deployment of the stent device 10. In this embodiment a total of two eyelets 44 is provided, which are arranged on the closed loops 38 so as to be at opposing sides of the stent device 10 in a radial direction in the assembled state. However, the arrangement and number of eyelets 44 may be chosen as desired. Furthermore, the eyelets 44 have a circular or rounded shape so as to facilitate fixation to and release from a delivery system. Alternatively, the eyelets may also comprise other shapes, preferably a symmetrical design, such as a polygonal or ellipsoid shape.

[0131] In FIGS. 11A and 11B a schematic top view and a perspective side view of a stent device 10 having an alternative support arm configuration is respectively shown.

[0132] In this configuration, a flexible region “in between” having a tapered section is not provided, as best shown by a direct comparison with the embodiment according to FIG. 9A, wherein constrictions are schematically indicated by sharp v-shaped notches. Instead, according to the embodiment of FIG. 11A, each support arm 18 comprises a tapered section, which gradually extends essentially from the concave portion 34 towards the second support region 22, i.e. towards the proximal tip end of the support arm 18. The tapering is provided as an essentially triangular or conical or ellipsoid shape and comprises a rounded portion at the proximal tip end, e.g. an end portion or loop portion, of the second support region 22, so as to reduce the risk of tissue damage.

[0133] At the same time, a spring function is maintained between the second support region 22 and the first support region 20, which is improved by a convex portion 32, which defines a shoulder or curvature of the first support region 20 with an adjacent concave portion 34 and which is linked to the distal end of the stent body 12, as shown in the perspective side view of FIG. 11B. The shoulder has a radius 46 at the distal end of the shoulder that is larger than a radius 48 at the proximal end of the shoulder. Accordingly, a wider angle is provided at the distal end of the stent body 12, which together with the radial extension of the convex portion 32 ensures that the likelihood of fractures occurring between the support arms and the stent body 12 is reduced and that forces acting upon the stent device 10 and the support arms 18 may be better distributed.

[0134] The smaller radius 48 at the proximal end of the shoulder furthermore ensures, together with the adjacent concave portion 34, that an improved adaptation to the annulus region and ventricular anatomy is provided. Furthermore, the radial extension of a radially outermost point of the convex portion 32—in radial direction—lies between a radially innermost point of the concave portion 34 and a proximal tip of the second support region 22, such that the proximal tip end of the second support region 22 has the largest radial extension of all sections of each support arm 18. Thereby, while providing an improved fitting or adaptation to the anatomical annulus region, a contacting surface is increased at the atrial portion and a wider support is provided without detrimentally affecting the remaining native structure of the annulus region.

[0135] In other words, the wider extension of the supporting regions of each support arm provide a larger engaging or interacting surface, while the particular configuration of the convex portion 32 and concave portion 34 as well as the radial extension of the second support region 22 ensures that an improved spring function is established with an improved absorption and distribution of forces acting upon the stent device.

[0136] Also shown in this embodiment is the mesh-shape of the body, which is here formed by a lattice of a plurality of diamond-shaped cells that are directly connected to each other and are essentially equal in size and/or shape. As outlined in the above, the diamond shape has the advantage of providing a substantially equal stress and strain resistance in the axial and circumferential direction and that the amount of deformation and strain applied during manufacturing may be reduced so as to increase the stability of the body. Furthermore, a required pliability may be retained, e.g. by varying thicknesses towards the proximal and/or distal ends.

[0137] It will be obvious for a person skilled in the art that these embodiments and items only depict examples of a plurality of possibilities. Hence, the embodiments shown here should not be understood to form a limitation of these features and configurations. Any possible combination and configuration of the described features can be chosen according to the scope of the invention.

LIST OF REFERENCE NUMERALS

[0138] 10 Stent device

12 Body

13 Strut

14 Cell

[0139] 15 Inner channel

16 Proximal end

17 Distal end

18 Support arm

[0140] 20 First support region
22 Second support region
24 Flexible region

26 Annulus

[0141] 27 Native cusp or leaflet
28 Ventricular portion
30 Atrial portion
32 Convex portion
34 Concave portion

36 Linking arm

[0142] 38 Proximal end portion or second closed loops
40 Fixation means or window
42 Delivery system

44 Eyelet

[0143] 46 Distal radius
48 Proximal radius