DE102010048368A1 - Medical device, in particular stent - Google Patents

Abstract

The invention relates to a medical device, in particular a stent, with a rotationally symmetrical lattice mesh (10) which can be converted from a radially compressed state to a radially expanded state and which comprises at least one first wire element (11) which, while forming at least one intersection point (15 ) is interwoven with at least one second wire element (12), at least the first wire element (11) being in the form of a band and having at least one widening (13) which is arranged at a distance from the intersection point (15).

Description

The invention relates to a medical device, in particular a stent. The invention relates in particular to a medical device or a stent with a rotationally symmetrical grid mesh.

Stents formed from interwoven wires are well known. In general, with a suitable design of the stent, on the one hand, sufficient radial force is to be achieved in order to support or stabilize a blood vessel. On the other hand, there is a need to set the wall thickness of the stent or the mesh as small as possible in order not to unnecessarily obstruct the blood flow within the blood vessel. However, if the mesh of the stent is made up of round wires, the reduction of the wall thickness is limited, since the use of thinner wires reduces the radial force at the same time.

From practice, stents are therefore also known, whose braid wires are band-like. The mesh of the known stents is thus formed by interwoven bands. Thus, a particularly thin-walled design of the mesh is achieved, whereby a hindrance of blood flow through a blood vessel is reduced and the risk of thrombogenicity is reduced. Usually, such bands have a comparatively large ratio between the width of the band and the thickness of the band or wall thickness of the lattice mesh. Due to the relatively large width of the bands compared to their height or thickness, a sufficient radial force is provided with simultaneously reduced wall thickness.

However, known stents with a braid woven from braids have disadvantages in terms of crimpability or compressibility. Specifically, the minimum diameter of the grid mesh, ie the crimp diameter or the diameter that is assumed in a feed system, is determined by the number of bands and their width. The minimum crimp diameter thus corresponds ideally to the formula D _MIN = number of _bands · width _bands / π

In order to provide a sufficient radial force, as can be seen from the above formula, the number of belts is limited at given diameters of the delivery system because a relatively large width of the belts is required to achieve the desired radial force.

The comparatively small number of bands or band-like widths prevents the use of the stent for influencing flow conditions in a blood vessel, in particular for covering an aneurysm. Due to the small number of bands, the meshes of the stent or the openings provided between the bands are relatively large, so that the openings can be flowed through substantially without resistance. Thus, the possibilities for retaining particles moving with the blood flow, for example particles which can detach from soft plaque or carotid stenoses, are limited. The known stent is unsuitable for influencing the flow and / or filtering of particles.

Although a flow control in known stents or lattice mesh could be achieved by an increased number of bands. However, this leads to the fact that the crimp diameter increases and thus the accessibility of a target vessel is impaired or the bandwidth is reduced, which has a direct effect on the radial force. Increasing the number of bands reduces the radial force.

The invention is based on the object to provide a medical device, in particular a stent, which allows for small wall thickness and sufficient radial force an efficient flow control.

According to the invention, this object is achieved by the subject matter of patent claim 1.

The invention is based on the idea of specifying a medical device, in particular a stent, with a rotationally symmetrical grid mesh. The grid mesh can be converted from a radially compressed state into a radially expanded state. Furthermore, the grid mesh comprises at least a first wire element, which is intertwined to form at least one crossing point with at least one second wire element. At least the first wire element is band-shaped and has at least one widening, which is arranged at a distance from the point of intersection.

The idea of the invention is to form at least one wire element of the lattice mesh band-shaped or as a band, wherein the band-shaped wire element at least partially has a broadening. In other words, the band-shaped first band element has a profiling or a variable width. The second wire element may be designed differently, in particular comprising a round wire element. Alternatively, the second wire element may also be formed band-shaped. In particular, it can be provided that all the wire elements are band-shaped. At least the first wire element comprises the broadening. The broadening is arranged at a distance from the point of intersection. This means that the first wire element is substantially narrower in the region of the crossing point than in a section outside the crossing point. The widening or the variable width of the wire element on the one hand enables the crimping or compression of the mesh to a relatively small cross-sectional diameter. Since the first wire element is formed at the crossing point substantially relatively narrow, so the crimpability is improved. At the same time, the broadening causes, in the expanded state, in particular in the implanted state, the rotationally symmetrical grid mesh to have a relatively large contact surface with a body hollow organ or that a relatively large surface of the grid mesh is covered. Thus broadening contributes significantly to improving flow control or particulate filtering.

In a preferred embodiment, the first wire element has a cross-sectional profile having a width and a height, wherein the width is greater than the height that substantially determines the wall thickness of the grid mesh. Specifically, the wall thickness of the grid mesh is determined by the height of the first wire element in conjunction with the height of the second wire element. In the crossing point, the first wire element and the second wire element lie on one another, so that the sum of the heights of the first wire element and the second wire element form the maximum wall thickness of the grid mesh. The determination of the height of the first wire element takes place substantially in the radial direction with respect to the axis of rotation of the grid mesh. The width of the first wire element, however, is determined substantially in the circumferential direction of the grid mesh. Overall, therefore, the width and the height of the first wire element are different, so that the contribution of the height or thickness of the wire element to the radial force of the mesh is reduced or attenuated. The first wire element thus makes it possible to reduce the wall thickness or the height of the wire element without negatively influencing the radial force.

Preferably, the broadening is arranged between two directly adjacent crossing points. The crossing points are formed on the one hand by the first wire element and on the other hand by the second wire element or another wire element. In general, it is advantageous if the widening are arranged, in principle, outside the crossing points of the lattice braid. This ensures that the wire elements in the crossing points have a relatively narrow cross-sectional profile, so that the grid mesh can assume a relatively small radially compressed state. Between the crossing points, the broadening is provided, which contributes to the improvement of the radial force. Thus, the medical device according to the invention enables, on the one hand, an improvement in the flow control and, on the other hand, an improvement or retention of the desired or required radial force.

According to a preferred embodiment of the medical device is provided that the widening extends at least partially into a mesh of the mesh. The grid mesh has at least one mesh, which is delimited at least by the first wire element and the second wire element. Preferably, the mesh of the mesh is limited by at least four wire elements, wherein one of the wire elements forms a first wire element according to the invention. The mesh of the lattice braid thus preferably comprises four crossing points, two crossing points being formed by the first wire element. In particular, a first intersection point is formed by the first wire element and the second wire element and a second intersection point by the first wire element and a further wire element. The widening of the first wire element is preferably arranged such that the widening extends at least partially into the mesh. The widening thus makes it possible, at least in sections, to cover the mesh of the mesh, so that the free opening formed by the mesh is reduced. Thus, the widening contributes favorably to the flow control.

In this context, it should be noted that the invention in the context of the application in the manufacturing state that is described in a fully radially expanded state, wherein act on the grid mesh substantially no external forces. The description of the invention therefore basically relates to the completely radially expanded state or production state, if not stated otherwise explicitly.

Preferably, the first wire element substantially has a non-round, in particular quadrangular, cross-sectional profile. Particularly preferred is a rectangular cross-sectional profile of the first wire element, since in this way on the one hand, the wall thickness of the mesh braid efficiently reduced and at the same time an increased radial force can be provided. The first wire element may further include edges that are bevelled or rounded. Moreover, it can be provided that the side or side surfaces of the first wire element, which extend substantially in the radial direction, curved, in particular with respect to the wire element arched outward, are. The band-shaped wire element can therefore essentially a flat profile with mutually parallel outer and Inner surfaces and outward curved side surfaces form.

The extension may be radially deflectable like a flap. The widening can therefore be flexible at least in sections. This applies in particular to the part of the broadening which forms the extension or projects beyond the width of the first wire element. The extension or part of the widening, which projects into the mesh of the grid mesh or projects beyond the width of the first wire element in the region of the crossing point, can in particular be designed so flexible that the widening, in particular the extension is radially deflectable. The radial deflectability of the broadening can also be effected by a torsion of the first wire element. For example, the first wire element can be so flexible that the broadening or extension can be deflected radially by twisting the first wire element, that is to say rotating about its longitudinal axis. In other words, the broadening, in particular the extension, is entrained by a twist of the first wire element or follows the torsion of the first wire element. This manifests itself in a flap-like arrangement or radial deflection of the extension or the entire widening. The radial deflection of the extension or broadening can also be effected by a combination of a torsion of the first wire element and a bend of the extension.

In general, the broadening can essentially form a flap. This has the advantage that medical functional elements can be passed through the meshes of the mesh. Although the grid mesh has a comparatively large covered surface, so that the flow of a body fluid, in particular of blood, can be influenced efficiently, the flexible or flap-like radially deflectable extension creates the possibility of medical functional elements, for example a coil catheter to pass the meshes of the mesh braid. Thus, the medical device according to the invention can be used advantageously for covering aneurysms, wherein the possibility is maintained of introducing coils into the aneurysm by means of a coil catheter through the meshes of the lattice mesh.

The extension can assume one side of the first wire element. The broadening preferably has at least one projection which projects beyond the width of the first wire element. In other words, the first wire element may comprise an asymmetrical or a symmetrical broadening. In the case of an asymmetrical broadening, it is preferably provided that the broadening in one direction proceeds starting from the longitudinal extension of the first wire element. The broadening forms an extension that protrudes on one side over the first wire element. Alternatively, two extensions may extend circumferentially from both sides of the first wire member. The widening can thus be symmetrical, so that the same profiling is shown on both sides of the first wire element. On the other hand, the extensions can also be formed on both sides of the first wire element in an asymmetrical design. Thus, the first wire element on both sides on different profiles.

In a preferred embodiment, the extension may have a smaller height than the first wire element. In particular, the projection may extend substantially wing-like laterally from the first wire element, wherein the extension is formed substantially thinner than the first wire element. It is generally provided that the broadening is formed with the first wire element in one piece or in one piece. In particular, the widening is formed by a profiling of the first wire element. Due to the reduced height of the extension of the widening with respect to the first wire element, an improved flexibility of the extension is achieved, so that the extension on the one hand in the radially compressed state of the grid structure can extend over other wire elements to improve the crimpability of the medical device. On the other hand, the increased flexibility of the extension by the reduced compared to the first wire element height allows an improvement of the flap function.

The widening, in particular the extension, can extend along an outer circumference and / or along an inner circumference. In particular, three variants can be distinguished. On the one hand, the broadening can be seen both on the outer circumference, as well as on the inner circumference of the grid mesh, wherein the extension preferably has the same height as the first wire element. The extension extends in the same circumferential plane, which also includes the first band-shaped wire element. On the other hand, the extension may have a smaller height than the first wire element, wherein the extension can be aligned flush with an outer surface of the first wire element. In this case, the broadening extends over the outer circumference of the grid mesh. Alternatively, the extension, which has a smaller height relative to the first wire element, are aligned with an inner surface of the first wire element, so that the widening is arranged substantially on the inner circumference of the lattice braid. It is not excluded that the broadening extends along a central circumferential plane which is arranged between the outer circumference and the inner circumference of the lattice braid. In particular, at least one extension of the broadening can be offset radially inwardly relative to the outer peripheral surface of the grid structure. Relative to the inner circumferential surface of the lattice structure, at least one extension of the widening can be arranged offset radially outward. In a specific example, at least one extension can be arranged centrally between the inner and the outer peripheral surface of the lattice structure. Alternatively, starting from the central arrangement, the extension can be arranged further inwards or farther out in each case at a distance from the inner or outer circumferential surface, ie between the middle position and the outer or inner position. The position of the extension in the radial direction can be achieved by etching the lattice structure on both sides.

According to a further preferred embodiment, the broadening, in particular the extension, preferably radially inwardly or radially outwardly curvable or twistable. A curvature of the broadening or the extension is advantageous in order to ensure a smooth transition of the mesh braid from a radially compressed to a radially expanded state. By a radially outward or a radially inwardly directed curvature, which occurs during the transition from the expanded state to the compressed state, it can be achieved that the widening or at least the extension easily and substantially without getting caught on adjacent wire elements slides. This facilitates retraction of the mesh in a catheter or generally a delivery system.

The curvature or torsion may be formed depending on the state of the mesh. For example, the compression of the mesh may cause a bowing of the extension of the broadening or a twist of the broadening. In particular, compression broadening for insertion into a catheter or generally a delivery system may be curved or twisted so that the broadening adapts to the curved inner surface of the delivery system. The torsion of the overall broadening or the curvature of the extension can also be effected in the expanded state or at least in the implanted state, for example by the action of a coil catheter. The broadening can be twisted or curved in a flap-like manner to release a mesh of the mesh, in particular for the purpose of passing a coil catheter through the mesh.

In this context, it should be noted that the broadening can also have at least two extensions, wherein a first extension radially inwardly and a second extension are curved radially outward or are curvable. Both extensions can be bendable in the same direction, ie radially inward or radially outward. In the curvature of the extensions, the band-shaped wire element remains substantially flush in the wall plane of the mesh. On the other hand, the torsion causes a rotation of the wire element, in particular the widening, about a longitudinal axis of the wire element, wherein the extensions projecting from the wire element on both sides can be arranged in a common, aligned plane. The common plane of the projections is deflected or rotated relative to the circumferential plane or peripheral surface of the mesh. A combined curvature / torsion of the broadening in the compression of the mesh may also be provided. It is possible that the wire element in regions outside the widening twisted around its own longitudinal axis, so that the widening is arranged substantially flat in a plane which is set against the peripheral plane of the rotationally symmetrical grid mesh.

The broadening or the first wire element in the region of the widening can have an S-shaped cross-sectional contour. The S-shaped cross-sectional contour can be created by a curvature of the extensions of the broadening of the first wire element.

In order to improve the crimpability of the medical device or of the rotationally symmetrical lattice mesh, it is preferably provided that the extension in the compressed state overlaps at least the second wire element or a further wire element. Thus, the extension or generally the widening, as shown in the formula shown in the introduction for the theoretical minimum crimp diameter, does not contribute to the width of the first wire element. The overlapping of the second and further wire elements by the extension of the widening allows a relatively small crimp diameter, while at the same time an improved flow control is achieved in the expanded state by the enlarged surface, which is provided by the widening.

In the expanded state of the mesh, the extension can overlap at least one mesh of the mesh. The overlap can be partial or in sections. In other words, the broadening can protrude into the mesh of the mesh and thus partially close the mesh. In general, the widening can be designed in such a way that, in the expanded state of the lattice braid, a partial covering or a partial closure of at least individual meshes of the lattice braid is made possible. The partial coverage can also be achieved in particular in that at least the extension of the Widening pores includes. Alternatively or additionally, the extension of the broadening is designed such that the surface of the extension is smaller than the opening area of the mesh of the mesh in the expanded state. Thus, a portion of the mesh of the mesh in the expanded state is not covered by the extension of the widening. Due to the partial closure of the mesh in the expanded state of the mesh, the endothelialization is promoted and also makes it possible for the meshes of the mesh to flow at least partially through the fluid, which is advantageous in particular when the medical device is arranged in vessel branches. Lateral body vessels can thus continue to be acted upon by a fluid flow, which penetrates through the open, so not covered, opening area of the mesh.

It is particularly preferred if the extension completely overlaps the mesh in the expanded state of the mesh. If a plurality of widenings are provided over the entire lattice mesh, it is possible in this way to achieve a partial or even complete coverage of the lattice mesh or of the meshes of the lattice mesh. For example, at least in a central region of the lattice braid, which is positioned, for example, in the region of an aneurysm, complete coverage of the lattice braid or meshes can be provided by a plurality of widenings. Thus, a body fluid flow can be completely prevented in some areas. Due to the flexibility of broadening still remains the possibility of penetrating mechanically through the mesh of the mesh, for example with a coil catheter.

Overall, a plurality of band-shaped first wire elements may be provided, each having at least one broadening. The first wire elements can each have several widenings. In particular, the first wire elements in each area between two crossing points may each comprise a widening. On the one hand, the plurality of first wire elements can be arranged substantially parallel to one another in the grid mesh. Alternatively, the plurality of first wire elements may be arranged crossing each other in the mesh. In general, both the first and the second or further wire elements may comprise spacers. In this case, the widenings can be arranged such that each mesh of the mesh is assigned at most a broadening, which covers the mesh at least partially. It is also possible that a part of the mesh of the lattice mesh has a broadening, in particular only a broadening. Another part of the mesh of the mesh may be formed without widening. Alternatively, the meshes of the mesh may each be associated with a plurality of widenings, which together lead to an at least partial, in particular complete, coverage of the mesh. The mesh can be partially covered in the expanded state of the mesh by several widenings or extensions of widening. The extensions of the spacers may together comprise an area or coverage area which is smaller than the opening area of the mesh in the expanded state of the grid mesh. Alternatively or additionally, the extensions or in general the widenings may have pores, so that partial coverage of the mesh is achieved. At least in the compressed state of the mesh mesh, the spacers may overlap. This ensures that the widenings do not or at least only slightly affect the crimpability of the mesh. It is also possible that the widenings in the expanded state of the grid mesh overlap, in particular to ensure complete coverage of one or more meshes of the grid mesh.

According to a further preferred embodiment of the medical device according to the invention, the first wire element is connected to the second wire element at at least one axial end of the mesh braid to form an end loop. Specifically, the first wire element can be connected to at least one axial end of the mesh with the second wire element to form an end loop, in particular be formed in one piece. In this way, free wire element ends are avoided at the axial ends or at least one axial end of the mesh braid. The first and second wire elements connected to an end loop reduce the risk of injury emanating from free wire element ends. The end loop allows the atraumatic design of the axial ends of the grid mesh.

The first wire element and / or the second wire element may have a taper in the region of a tip of the end loop. In particular, a transition region may be provided between the first and the second wire element at the tip of the end loop, which comprises the taper. In other words, the transition region has a smaller width than the first wire element and / or the second wire element. In general, the connection of the first wire element with the second wire element in the connection area causes an increased radial force. However, the taper at the tip of the end loop reduces the radial force so that the radial force is equal over the entire length of the mesh. Further, the taper at the tip of the end loop causes the end loop to be crimped is without setting up radially. In other words, when compressing the mesh, the end loop does not deviate in the radial direction, but remains substantially in the peripheral plane of the mesh. Due to the taper in the region of the tip of the end loop, the local radial force at the axial end of the mesh can be reduced to such an extent that substantially the same radial force is established over the entire length of the mesh. This prevents the axial ends of the lattice mesh from being pressed more strongly into a vessel wall of a hollow body of the body than, for example, a central region of the lattice mesh. The invention does not exclude that the wire elements on at least one axial end of the mesh braid comprise open wire ends.

According to a further preferred embodiment of the medical device according to the invention it is provided that the widening is formed asymmetrically with respect to a longitudinal extension of the first wire element, so that a first extension of the widening further projects beyond the width of the first wire element than a second extension of the widening. When compressing the grid mesh, the first and / or second extensions of adjacent first wire elements overlap. Due to the asymmetrical design of the broadening or asymmetric profiling of the first wire element to form the asymmetric broadening, the overlap of the extensions can be improved.

The grid mesh may have at least one circumferential segment of immediately adjacent meshes. At least a portion of the stitches, in particular all stitches, of the circumferential segment can each be assigned at least one widening. The circumferential segment is preferably formed as a ring of immediately adjacent meshes of the mesh.

In each case, the first extensions of the widenings of the circumferential segment can be oriented essentially in the same circumferential direction, so that the widenings overlap in a scale-like manner in the compressed state of the lattice mesh. In particular, the first extensions in the compressed state of the mesh may overlap the second extensions. Advantageously, it is provided that the first extensions are oriented in the same or alternately in different axial directions. Generally, the extensions have a peripheral component and an axial component with respect to their extension from the wire element. Advantageously, the first extensions of the widenings of the circumferential segment are arranged such that the first extensions have substantially the same peripheral component or are oriented in the same circumferential direction. The axial component of immediately adjacent extensions of the circumferential segment, however, may be different. The orientation of the projections in the same circumferential direction has the advantage that the projections can overlap uniformly and like a tile in compressing the mesh, whereby a substantially uniform outer diameter of the mesh is achieved. If the first extensions of the widenings of the circumferential segment are oriented in the same axial direction or have the same axial component, in the compressed state of the lattice mesh a ring segment comprising the extensions or extensions and an axially adjacent ring segment, the wire element sections without broadening having. The first extensions can also be oriented alternately in different axial directions or have alternately different axial components. Preferably, the first extensions are axially oriented in a distal direction relative to a delivery system for the medical device. This has the advantage that the supply of a coil catheter is facilitated by a mesh of the mesh network, since the first extensions are oriented substantially in the same direction, which also corresponds to the feed direction of the coil catheter. An entanglement of the coil catheter when penetrating a mesh of the mesh is thus avoided.

In the expanded state of the mesh, several extensions may overlap. In other words, the extension of the first wire element in the expanded state can overlap at least one extension of another wire element at least in sections. In principle, the extension of the first wire element can overlap or cover one or more meshes of the mesh braiding in the expanded state. The additional or additionally covered meshes may have wire elements without a broadening or be formed completely widening free.

The invention is explained in more detail below on the basis of exemplary embodiments with reference to the accompanying schematic drawings. Show in it

1 a detailed view of a grid mesh known from practice with band-shaped wire elements;

2 a detailed view of a medical device according to the invention with a plurality of band-shaped wire elements, each having a plurality of spacers, according to a preferred embodiment;

3 a detailed view of the medical device according to 2 wherein the broadening has a perforation;

4 the medical device according to 2 in a compressed state;

5 a detail view of a medical device according to the invention according to a preferred embodiment in the compressed state, wherein a band-shaped wire element has a one-sided widening;

6 a detail view of a medical device according to the invention according to a preferred embodiment in the compressed state, wherein two substantially parallel band-shaped wire elements each have a one-sided widening;

7 a detail view of a medical device according to the invention according to a preferred embodiment, wherein a band-shaped wire elements has a one-sided widening, which overlaps a mesh of the grid mesh;

8a . 8b . 8c in each case a medical device according to 2 in which the spacers are arranged at different circumferences of the mesh, during manufacture on differently structured braided spines;

9 a cross-sectional view of a first wire member of a medical device according to the invention according to a preferred embodiment, wherein the broadening is curved in a deformed state in different directions;

10a a cross-sectional view of a first wire member of the medical device according to the invention according to a preferred embodiment in the region of broadening;

10b a cross-sectional view according to 10a wherein the wire element has a smaller height at a crossing point than distant from a crossing point;

11a a detail view of a medical device according to the invention according to a preferred embodiment, wherein the connection of a first wire element is shown with a second wire element to an end loop;

11b the detailed view according to 11a , wherein a taper is arranged in the region of a tip of the end loop;

11c an end loop according to 11a wherein the connection between the first wire element and the second wire element is made by a rivet;

12a . 12b in each case a detailed view of a medical device according to the invention with a plurality of band-shaped wire elements, each having a plurality of asymmetric extensions, according to a preferred embodiment; and

13a . 13b in each case a detailed view of a medical device according to the invention with a plurality of band-shaped wire elements, each having a plurality of spacers with a single, one-sided extension, according to a preferred embodiment.

In 1 is a section of a known from practice grid mesh 10 ' shown, wherein the grid mesh 10 ' several interwoven wire elements 11 ' . 12 ' includes. The wire elements 11 ' . 12 ' intersect, creating crossing points 15 ' are formed. The wire elements 11 ' . 12 ' are formed band-shaped. That means the wire elements 11 ' . 12 ' each having a cross-sectional profile having a height and a width, wherein the height is smaller than the width. The grid 10 ' according to 1 is shown in compressed state. The arrow in 1 It is clearly visible that the minimum crimp diameter, ie the cross-sectional diameter of the rotationally symmetrical lattice mesh 10 ' in the highest possible compressed state, by the width of the wire elements 11 ' . 12 ' is determined. In particular, the width of the wire elements has a limiting effect here 11 ' . 12 ' in the area of crossing points 15 ' , In summary, the width of the band-shaped wire elements 11 ' . 12 ' in that either the minimum crimp diameter is not sufficiently small around the grid mesh 10 in a feeding system, or if the width of the wire elements 11 ' . 12 ' correspondingly small is chosen, that the grid mesh 10 ' does not include sufficient radial force. Although it is possible to provide a sufficient radial force by a comparatively small number of wire elements 11 ' . 12 ' on the circumference of the grid mesh 10 ' is arranged, wherein the wire elements 11 ' . 12 ' comprise a comparatively high width. Such a configuration, however, adversely affects the filter function of the grid mesh 10 ' out. In particular, the particle filtration of a grid mesh designed in this way has 10 ' proved inadequate.

According to the invention, therefore, the width of at least one first band-shaped wire element is provided 11 or a band along the wire element 11 to vary. In particular, the first wire element 11 at least one broadening 13 on, from a crossing point 15 passing through the first wire element 11 with a second wire element 12 is formed, is spaced. It is not excluded that the thinnest portion of the first wire element 11 based on the width of the wire element outside the crossing point 15 is arranged. The first wire element 11 for example, between the broadening 13 and the crossroads 15 have a section that is smaller in width than the broadening 13 and a smaller width than the first wire element 11 in the area of the crossing point 15 having. The broadening 13 in the meaning of the application is at least spaced from at least one intersection point 15 of the lattice braid 10 arranged. In other words, the widest point or the widest region of the first wire element 11 outside a crossroads 15 arranged. The widest point or widest region of the first wire element 11 makes the broadening 13 or at least part of the broadening 13 ,

2 shows a section of a corresponding grid mesh 10 for a medical device, in particular a stent, wherein the grid mesh 10 several wire elements 11 . 12 includes. In particular, two first wire elements 11 shown with two second wire elements 12 are intertwined. The first wire element 11 forms with the second wire element 12 at least one crossing point 15 , where in 2 four crossing points 15 are shown. The wire elements 11 . 12 according to 2 are each formed band-shaped. The first wire elements 11 and the second wire elements 12 Thus, each have a cross-sectional profile with a width and a height, wherein the width is greater than the height. The height is determined in the radial direction relative to the axis of rotation of the rotationally symmetrical grid mesh. The width, however, extends predominantly in the circumferential direction of the grid mesh 10 , Between every two crossing points 15 have the wire elements 11 . 12 each a widening 13 on. The basic structure of the band-shaped wire elements 11 . 12 is also disclosed in connection with the other examples. Overall, each wire element 11 . 12 several extensions 13 assigned. The wire elements 11 . 12 according to 2 include symmetrical extensions. In other words, the width of the wire elements changes 11 . 12 between two crossing points 15 symmetrical. The wire elements 11 . 12 point between two crossing points 15 which are immediately adjacent, a wire element portion having a greater width than another wire element portion, which in the crossing point 15 is arranged. The widened wire element section, in particular the widest point of the wire element 11 . 12 between two crossing points 15 includes, is called broadening 13 designated.

In 2 are four wire elements 11 . 12 represented, the total of four crossing points 15 form. In this case, the first wire elements run 11 parallel to each other. Likewise, the second wire elements extend 12 parallel to each other, wherein the second wire elements 12 the first wire elements 11 essentially cross at right angles. In general, the first wire elements can 11 and the second wire elements 12 crossing at different angles. Preferably, the first wire elements intersect 11 with the second wire elements 12 at an angle of greater than 0 ° and at most 180 °. All angles between these values are possible. This generally results in a diamond-shaped geometry of the mesh 14 ,

2 corresponds to the manufacturing state or fully expanded state of the grid mesh 10 , Between the first wire elements 11 and the second wire elements 12 is a scam 14 formed of the grid. The broadening 13 at least partially stick in the loop 14 into it. This results in a substantially cross-shaped mesh profile or opening profile of the mesh 14 ,

The broadening 13 are essentially all the same shape. It is also possible that the broadening 13 have different shapes or profiles. In general, the wire elements 11 . 12 have a cross-sectional profile extending in the longitudinal direction of the wire elements 11 . 12 changes. For example, the band-shaped wire elements 11 . 12 in the crossing points 15 include a concave curvature. Outside the crossing points 15 especially in the area of widening 13 can the wire elements 11 . 12 form a convex curvature. Preferably, there is between the concave curvature and the convex curvature of the wire elements 11 . 12 a continuous transition.

The wire elements 11 . 12 each have side edges 21 on, in the area or in the vicinity of the crossing points 15 run essentially straight. Distant from the crossing points 15 or between two crossing points 15 have the side edges of the wire elements 11 . 12 one each with respect to the longitudinal direction of the wire element 11 . 12 outward curvature on. The curvature or curvature can be substantially continuous. Alternatively it can be provided that the broadening 13 has a substantially rectangular profile, wherein the side edge 21 takes a discontinuous course.

3 shows a detail view of a medical device according to a preferred Embodiment, wherein a single broadening 13 a wire element 11 . 12 is shown. The wire element 11 . 12 points in the area of broadening 13 a perforation 19 on. This ensures that the endotelialization and the flow of blood through the wall of the medical device or through the rotationally symmetrical grid mesh 10 is favored. In particular, when the medical device is implanted as a stent in a blood vessel, the perforation allows 19 the blood flow into branching blood vessels. In place of the perforation 19 may be a different structuring in the area of broadening 13 be provided. For example, the wire element 11 . 12 in the area of broadening 13 Grooves and / or protrusions comprise the adhesion of the grid mesh 10 to increase on a vessel wall, or to favor the attachment of endothelial cells. The grooves and / or protrusions may also be in the wire elements 11 . 12 be educated. Specifically, the wire elements 11 . 12 include grooves and / or projections in total, ie in particular outside the widenings 13 , Furthermore, the wire elements 11 . 12 include a total perforation to aid in the attachment of endothelial cells or blood flow into branching blood vessels. The perforation, the grooves and / or the projections are therefore not on the broadening 13 or an extension 13a . 13b the broadening 13 Restricted, but can also over other areas or sections of the wire elements 11 . 12 extend.

In 4 is the grid 10 according to 2 shown, wherein the grid mesh 10 according to 4 is present in the compressed state. It can be seen that the broadening 13 the first wire elements 11 and the second wire elements 12 can overlap in the compressed state. This further reduces the minimum crimp diameter. At the same time allows broadening 13 an increase in the radial force of the lattice mesh 10 ,

In the embodiment according to 2 and 4 is provided that all wire elements 11 . 12 each several widenings 13 include. Alternatively, it may be provided that, as in 5 shown, the broadening 13 only on the first wire elements 11 is provided. The second wire elements 12 can be formed without widening. In general, several extensions 13 over the entire peripheral surface or the peripheral wall of the grid mesh 10 be arranged distributed. For example, a part of the wire elements 11 . 12 extensions 13 include. The wire elements 11 . 12 may have different sections, some with extensions 13 and partly without broadening 13 are equipped. The grid 10 can have a total of areas that have multiple stitches 14 and wire element portions of the wire elements 11 . 12 comprising, wherein the grid mesh 10 may have different areas, characterized by the size, shape and / or number of widenings 13 can distinguish. For example, the size of the widenings 13 from the middle of the grid 10 proceeding in the longitudinal direction on the axial ends of the mesh braid 10 to become smaller. In the edge regions or axial end regions of the lattice mesh 10 are smaller broadening 13 as in a central region of the lattice network 10 intended. Analog can be the number of widenings 13 per circumference segment 23 decrease toward the axial ends, in particular such that the axial end portions of the grid mesh 10 are formed widening. By the aforementioned measures, the perfusion of secondary vessels and the endothelialization of the lattice mesh 10 at least in the axial end regions of the lattice mesh 10 get supported. The different areas of the grid 10 can also be characterized by the presence of broadening 13 differ in themselves. For example, the ratio of meshes can be 14 with broadening 13 to stitches 14 without extensions 13 per ring segment or circumference segment 23 in the longitudinal direction along the grid 10 to change. It is also possible that the grid mesh 10 only on one side, ie in a circumferentially limited area or in an area that does not extend over the entire circumference of the grid mesh 10 extends, with spacers 13 Is provided. Such a design of the grid mesh 10 is particularly advantageous for the treatment of aneurysms, the area with widening 13 covering the aneurysm.

The broadening 13 includes at least one extension 13a . 13b that is starting from the wire element 11 . 12 into the net 14 of the mesh braid extends. The extension 13a . 13b So stands over the wire element 12 in front. In particular, the extension is 13a . 13b in the circumferential direction over the wire element 11 . 12 before or extends in the wall plane of the mesh braid 10 , The extension 13a . 13b forms together with the wire element 11 . 12 the broadening 13 , In other words, the broadening indicates 13 a width equal to the sum of the width of the wire element 11 . 12 and the extension 13a . 13b equivalent.

The broadening 13 according to 2 and 4 has two extensions 13a . 13b on, which is on both sides of the wire element 11 . 12 extend. The two extensions 13a . 13b are similarly shaped, so that in total a symmetrical profiling of the wire element 11 . 12 or a symmetrical broadening 13 results. In particular, the broadening indicates 13 a first extension 13a and a second extension 13b on, with the first extension 13a a reflection of the second extension 13b along a longitudinal axis of the wire element 11 . 12 equivalent. Alternatively, the first extension 13a and the second extension 13b have different geometric shapes. In particular, the first extension 13a continue over the wire element 11 . 12 protrude as the second extension 13b , This results in an asymmetric broadening 13 or profiling of the wire element 11 . 12 ,

The extensions 13a . 13b the broadening 13 not only on both sides of the wire element 11 . 12 be trained, as in the 2 and 4 shown. Rather, it is also possible that the broadening 13 one-sided from the wire element 11 . 12 goes out or a single extension 13a includes. Such a broadening 13 is in 5 shown, where 5 the compressed state of the grid mesh 10 shows. The only extension 13a the broadening 13 overlaps at least a second wire element 12 , in particular a second wire element 12 as well as two further first wire elements 11 , Thus, the minimum crimp diameter in the medical device according to the invention is determined by the width of the band-shaped wire element 11 . 12 in the area of the crossing point or crossing points 15 , The extensions 13a the broadening 13 essentially do not contribute to the minimum crimp diameter. Thus, the width of the wire elements 11 . 12 at least in the area of the crossing points 15 are chosen so small that the medical device can be introduced into a delivery system. By the broadening 13 or the multiple spacers 13 the flow control and particle filtration function of the medical device is met, so that the number of band-shaped wire elements 11 . 12 of the lattice braid 10 can be reduced.

Overall, it is provided that the band-shaped wire elements 11 . 12 are formed in the invention wider than known medical devices. This is possible because the number of band-shaped wire elements 11 . 12 can be reduced in the medical device according to the invention. The filter function or the function of influencing the flow is still fulfilled because the band-shaped wire elements 11 . 12 have a profiling that broadening 13 forms. Because the wire elements 11 . 12 are generally wider than in known medical devices, increases the stability of the mesh according to the invention 10 especially in the area of crossing points 15 , Thus, the grid mesh 10 in the area of crossing points 15 an improved radial force.

The extension 13a the broadening 13 according to 5 is formed substantially tongue-like and extends on one side of the first wire element 11 , A similar design of broadening 13 shows 6 , wherein according to 6 two first wire elements 11 each a widening 13 include. The extensions 13a the broadening 13 the first wire elements 11 are designed oriented in different directions. The minimum crimp diameter is thus also not adversely affected. Overall, it can be provided that the widening 13 essentially pattern over the grid 10 are arranged. In the embodiment according to 6 is provided in particular that the extension 13a the broadening 13 in each case further wire elements 11 . 12 or areas of the wire elements 11 . 12 covered, no broadening 13 include. On the other hand, can also be provided, such as in 4 shown that the extension 13a in the compressed state of the lattice mesh 10 further broadening 13 overlaps.

An overlap of wire elements 11 . 12 through extensions 13a . 13b the broadening 13 can be advantageous not only in the compressed state, but also in the expanded state. Such a configuration is for example in 7 shown. 7 shows a mesh 14 a grid mesh 10 , the mesh 14 by two first wire elements 11 and two second wire elements 12 is formed. The first wire elements 11 and the second wire elements 12 intersect in each case at a crossing point 15 , A first wire element 11 includes a broadening 13 with a one-sided extension 13a who in use over the mesh 14 extends and the mesh 14 essentially completely, but at least largely covering. The extension 13a goes unilaterally from the first wire element 11 and is formed substantially rectangular with rounded edges. By the extension 13a the broadening 13 is chosen so large that the extension 13a in the expanded state, the mesh 14 of the lattice braid 10 overlaps, the crimping of the mesh will be 10 simplified and tilting several extensions 13 at the transition of the lattice mesh 10 from the radially expanded to the radially compressed state avoided.

An alternative in which the crimping by a sliding movement of the extensions 13a . 13b the broadening 13 on the grid 10 can be simplified by appropriate deformation of the broadening 13 be effected. Specifically, the broadening 13 , in particular the extension 13a or the extensions 13a . 13b , at least partially deformed in the radial direction or with respect to the circumferential plane of the grid mesh 10 be employed. In 8th an embodiment of such a medical device is shown, wherein the grid mesh 10 several wire elements 11 . 12 each with several extensions 13 includes. The broadening 13 on the one hand have different Geometries and on the other hand, a different radial position with respect to the longitudinal axis of the grid mesh 10 on. The broadening 13 Correspondingly, they correspond essentially to the broadening 13 according to 2 , The broadening 13 have in particular an onion-like profile. The areas marked in gray (see reference numeral 24 ) are arranged in a different altitude or in a different radial position, as the marked, ie not highlighted gray broadening 13 , The respective broadening 13 are thus in different peripheral surfaces or at different levels, for example, based on a cylindrical shell reference surface or relative to the central axis.

The configuration according to 8a . 8b and 8c can be achieved for example by the fact that the rectangular widenings 13 while braiding the grid 10 on a wicker thorn on raised areas or projections 24 of the wicker thorn. The projections 24 In some areas, there are increases in the plait, with the widening 13 provided with wire elements 11 . 12 be wound on the wicker thorn so that at least some widening 13 on the tabs 24 to be ordered. Subsequent heat treatment can change the shape of the lattice mesh 10 with those over other broadening 13 increased broadening 13 be fixed. By after braiding the grid 10 Heat treatment can also be adjusted, which areas or which broadening 13 of the lattice braid 10 in the compressed state on the outer circumference of the grid mesh 10 or the inner periphery of the mesh braid 10 slide.

Another way, the overlapping of the extensions 13a . 13b in a relative movement of the extensions 13a . 13b to allow each other, is the shape of the extensions 13a . 13b or in general the form of the widening 13 , which extends in the circumferential direction, to the curvature of the cylindrical mesh braid 10 adapt. The curvature of the cylindrical grid 10 refers to the expanded state, in particular to the expanded state in the vessel. In contrast to the example described above, in which the extensions 13a . 13b extend tangentially with respect to the circumferential curvature of the grid structure, are the extensions 13a . 13b according to the curvature of the lattice structure or of the lattice mesh 10 curved and are thus substantially in the peripheral surface of the mesh 10 arranged. It can be provided that the extensions 13a . 13b have different degrees of curvature, ie have different radii of curvature. The radii of curvature are adjusted so that adjacently arranged extensions 13a . 13b , resulting in a relative movement of the extensions 13a . 13b , in particular when crimping move over one another, can slide on each other. It is possible that extensions 13a . 13b have a smaller radius of curvature or are more curved than the curvature of the lateral surface of the lattice mesh 10 , Other extensions 13a . 13b have the same or a larger radius of curvature than the curvature of the mesh 10 on. The different radii of curvature of the different extensions 13a . 13b As described above, each may be combined with each other. Another advantage of the inwardly curved extensions 13a . 13b is that they are well adapted to the curvature of the vessel wall.

Preferably, the grid mesh 10 from a metal, in particular a shape memory metal, for example Nitinol formed. The production of the lattice mesh 10 or the wire elements 11 . 12 can also be done by a physical vapor deposition method, such as sputtering. In this case, the deformation of the individual wire elements 11 . 12 or the widening 13 , In particular in the radial direction with respect to the longitudinal axis of the grid mesh 10 be accomplished by the use of a corrugated or otherwise structured substrate. Alternatively, a temporally downstream deformation of the wire elements 11 . 12 or broadening 13 respectively.

For easy compressibility of the grid mesh 10 or in general the medical device, it is expedient to take measures that a hooking or tilting of the widening 13 prevent compression. According to 9 is intended to go there, the broadening 13 or at least one or two extensions 13a . 13b the broadening in the radial direction with respect to the longitudinal axis of the grid mesh 10 to deform. For example, the broadening 13 with the first wire element 11 be twisted. 9 shows a first wire element 11 in cross-section with a broadening 13 (dashed line), which is twisted substantially S-shaped or slightly twisted. The broadening 13 has two side surfaces 21 on, with a first side surface 21a in the radial direction relative to the grid mesh 10 is placed radially outward and a second side surface 21b is deflected radially inward. In this way, the gliding becomes the broadening 13 above or below other wire elements 11 . 12 or broadening 13 in the compression of the lattice mesh 10 simplified. The preparation of such an S-shaped twist of broadening 13 For example, it can be done such that the grid mesh is braided on a braiding mandrel with subsequent heat treatment, the braiding mandrel having a corresponding surface structuring. Of the Braided mandrel thus preferably has a structuring, so that when braiding the mesh braid 10 the broadening 13 are arranged on the structuring that results in the salaried or radially deflected configuration. In particular, the braiding mandrel or heat treatment mandrel can be profiled or structured such that the broadening 13 with an angle of attack with respect to the longitudinal axis of the grid mesh 10 be formed. The radial deflection of the widenings 13 or at least one extension 13a . 13b the broadening 13 can also with an asymmetric design or profiling of the wire elements 11 . 12 respectively. For example, the broadening 13 a single extension 13a have, which is unilaterally of the wire element 11 . 12 extends. The only extension 13a can be radially deflected or radially deflectable. The deflection can be caused by torsion of the wire element 11 . 12 take place, with a simple, especially not S-shaped, twist is possible. This applies to both symmetric and asymmetric shaped spacers 13 ,

According to a further preferred embodiment, it is provided that the extension 13a . 13b the broadening 13 has a smaller height than the associated wire element 11 . 12 , The sliding of the extension 13a . 13b over the grid 10 , Especially at a transition of the grid mesh 10 from a radially expanded state in a radially compressed state, is improved in this way. In particular, the extension 13a . 13b , opposite the wire element 11 . 12 is formed thin-walled, increased flexibility or deformability or drivability in the expanded state. This will allow the broadening 13 , in particular the extension 13a . 13b flap-like is deflectable. Generally, the extension extends 13a . 14b in a mesh 14 of the lattice braid 10 , This covers the extension 13a . 13b at least part of the mesh 14 , When using the medical device as a stent to cover an aneurysm, it is advantageous if the mesh 14 of the stent or grid mesh 10 at least for the introduction of a coil catheter in the aneurysm are continuous. At the same time the stitches should 14 be covered to prevent blood flow into the aneurysm. The flexible extension 13a . 13b has both properties. On the one hand, the extension covers 13a . 13b the mesh 14 partially, so that blood flow into the aneurysm is reduced or at least reduced. On the other hand, the flexibility allows broadening 13 a flap-like function of broadening 13 or the extension 13a . 13b so that a coil catheter through the mesh 14 into an aneurysm. This is at least the extension 13a . 13b radially deflected. After retraction of the coil catheter, the extension takes 13a . 13b the original position again and covers the mesh 14 , The aforementioned function of the widenings 13 can by twisting the wire element 11 . 12 be effective. By the twist of the wire element 11 . 12 becomes the broadening 13 at least partially deflected radially out of the wall plane of the mesh and mesh with opposite twist again in alignment with the wall plane of the mesh 10 brought. This is especially true even if the broadening 13 the same height or thickness as the wire element 11 . 12 having.

Even if the extension 13a . 13b a smaller wall thickness or height than the wire element 11 . 12 has sufficient radial force is guaranteed.

10 shows a cross section through a wire element 11 . 12 with a broadening 13 , where the extension 13a . 13b the widening a smaller wall thickness or height than the wire element 11 . 12 having. The wire element 11 . 12 points in the area of broadening 13 essentially a T-shaped cross section. In other words, the extensions extend 13a . 13b wing-like from the wire element 11 . 12 path. The broadening 13 can, as in 10a shown on an outer periphery of the grid mesh 10 be arranged. The extensions are aligned 13a . 13b with a radially outer surface of the wire element 11 . 12 , Alternatively, the extensions can 13a . 13b on an inner circumference of the mesh braid 10 from the wire element 11 . 12 out. The extensions 13a . 13b then aligned with an inner surface of the wire element 11 . 12 , Furthermore, it can be provided that the extensions 13a . 13b between an outer surface of the wire element 11 . 12 and an inner surface of the wire member 11 . 12 , ie essentially from the side surfaces of the wire element 11 . 12 out. The extensions 13a . 13b So can essentially between the outer periphery of the mesh 10 and the inner periphery of the mesh braid 10 in the circumferential direction of the wire element 11 . 12 extend away. It can the extensions 13a . 13b the same height or thickness as the wire element 11 . 12 exhibit.

In addition, it can be provided that the wire element 11 . 12 has different wall thicknesses or heights. In particular, it can be provided that the wire element 11 . 12 in the area of the crossing point 15 has a smaller wall thickness or height than outside the crossing point 15 , In this way, the total wall thickness in the area of the crossing points 15 of the lattice braid 10 be reduced. 10b shows a cross section through a wire element 11 . 12 of the lattice braid 10 with a broadening 13 , wherein the dashed line shows a visible edge of a wire element portion having a smaller height or wall thickness than that in the Drawing plane cut wire element portion of the wire element 11 . 12 , As in 10b can be seen, the wire element 11 . 12 in the area of broadening 13 a greater wall thickness or height than in a crossing point 15 on, wherein the wall thickness or height of the wire element 11 . 12 in the area of the crossing point 15 is shown by the dashed line. It is preferably provided that the wire elements 11 . 12 at the crossroads 15 each have a height that is half as large as the height of the wire elements 11 . 12 outside the crossroads 15 , In this way, over the entire length or over the entire circumference of the lattice mesh 10 essentially a uniform wall thickness can be adjusted.

The different wall thicknesses of the wire elements 11 . 12 or broadening 13 may preferably be produced by a combined sputtering etching process. In particular, the thickness or height of the widenings 13 be reduced by etching. In this case, the etching process is preferably set such that a thin material layer remains, which widening 13 forms.

The smaller wall thickness or height of the wire element 11 . 12 in the crossing points 15 can also be done by etching the wire elements 11 . 12 in the areas of crossing points 15 respectively. In this case, the wire elements 11 . 12 be etched on one side, so that one-sided recesses are formed. The recesses are preferably shaped such that in the braided configuration another, in particular intersecting, wire element 12 . 11 can be arranged in the recess. The recesses may have a length which is greater than the width of the band-shaped wire element 11 . 12 is. This will ensure that the wire element 11 . 12 at the crossroads 15 both in the compressed state of the mesh braid 10 , as well as in the expanded state, are located inside the recess. The recesses thus preferably have a length which is a sliding of the first wire element 11 on the second wire element 12 within the recess over the entire range of movement between compressed state and expanded state of the mesh 10 guaranteed. The wall thickness of the grid mesh 10 is thus reduced. It is also possible that both sides of the wire element 11 . 12 Recesses are formed. The wire element 11 . 12 can therefore both on an outer circumference, as well as on an inner circumference of the lattice mesh 10 each having a recess. This has the advantage that in a Flechtart, wherein the wire element 11 . 12 each with another wire element 12 . 11 and then under another wire element 12 . 11 (1-over-1-braiding) is guided, the other wire elements 12 . 11 are each arranged in one of the two recesses. When the wire elements 11 . 12 are basically formed with a plurality of recesses on both sides (outer surface and inner surface), different types of braids can be realized. For example, a 1-over-2 plait, a 1-over-3 plait, a 2-over-2 plait, a 2-over-3 plait or other plaits may be provided.

At the axial ends of the mesh braid 10 can the wire elements 11 . 12 be arranged freely. The grid 10 So can include free wire ends at the axial ends. Alternatively it can be advantageously provided, the wire elements 11 . 12 at the axial ends of the mesh braid 10 connect to. In particular, the first wire element 11 with a second wire element 12 in the region of an axial end of the lattice braid 10 to an end loop 16 be connected as in 11a shown. The connection can be made in a positive, non-positive or cohesive manner. Preferably, the wire elements 11 . 12 in the area of the end loop 16 formed in one piece. The end loop 16 includes a tip 17 , which is a-traumatic for lack of free wire element ends. In the area of the end loop 16 may also have broadening 13 be formed, with the broadening 13 between the top 17 and one crossing point each 15 are arranged.

The production of the loops 16 For example, by deflecting a wire element 11 . 12 done on a wicker thorn. In this case, the braiding mandrel preferably has a pin around which the wire element 11 . 12 is diverted. Alternatively, the end loop 16 already in the production of the wire element 11 . 12 arise. For example, the wire element 11 . 12 be prepared by a combined sputter etching process, wherein at the same time the end loop 16 is formed. When using wire elements 11 . 12 which are produced by a conventional manufacturing process, for example by drawing, the profile or the widenings 13 are formed by laser cutting, the formation of the end loop takes place 16 preferably by a deformation of the wire element 11 . 12 , By a subsequent heat treatment, stresses arising during the deformation in the material of the end loop 16 reduced.

To the formation of the end loop 16 to simplify and increased radial force and thus distortion in the end loop 16 To avoid, it has proved to be advantageous, the width of the band-shaped wire element 11 . 12 in the area of the top 17 the end loop 16 to reduce. In particular, it can be provided that the end loop 16 in the area of the top 17 a rejuvenation 18 having. The rejuvenation 18 corresponds to a position of the wire element 11 . 12 which has a smaller width than the other sections of the wire element 11 . 12 , An end loop with such a taper 18 is in 11b shown.

Alternatively, the end loop 16 by the connection of two separate wire elements 11 . 12 be prepared as in 11c shown. In particular, the band-shaped wire elements 11 . 12 comprise recesses or openings at the wire ends, wherein the wire elements 11 . 12 be connected by a separate, additional element. The connection of the wire elements is preferred 11 . 12 through a rivet 20 , The rivet forms 20 a rotation axis, so that the wire elements 11 . 12 on the one hand connected to each other and on the other hand to each other are pivotable or rotatable. In particular, by the rivet 20 a relative angular movement between the wire elements 11 . 12 allows. The rivet 20 can the wire elements 11 . 12 also fix it, so that through the rivet 20 no rotation axis is formed. In this case can be used to compress the grid mesh 10 a bend of the wire elements 11 . 12 be enough. Other types of connection, for example, with sleeves, by welding or soldering or other additional fasteners are possible.

12a shows a section of a grid mesh 10 with several wire elements 11 . 12 , where the wire element 11 . 12 are each formed band-shaped. The wire elements 11 . 12 each comprise several widenings 13 between each two crossing points 15 are arranged. The broadening 13 are asymmetrical. That means the broadening 13 each a first extension 13a and a second extension 13b include, wherein the first extension 13a continue over the wire element 11 . 12 as the two extension 13b protrudes. The asymmetric arrangement facilitates overlapping of the extensions 13a . 13b the broadening 13 in the circumferential direction in the compression of the mesh 10 , In particular, the asymmetric design of the spacers 13 achieved that the first extensions 13a in the compressed state of the lattice mesh 10 the second extensions 13b overlap like scales 12b shown. It can be provided that the first and second extensions 13a . 13b in the compressed state of the lattice mesh 10 overlap and in the expanded state of the grid mesh 10 no overlap occurs. The overlap of the extensions 13a . 13b may also be in the implanted state of the lattice braid 10 demonstrate. In the implanted state, the grid mesh 10 essentially a smaller cross-sectional diameter than in the manufacturing state. The geometry or size of the extensions 13a . 13b can be adjusted so that no overlap occurs in the production state and in the implanted state, an overlap. The size of the extensions 13a . 13b can also be sized so that the extensions 13a . 13b in the production state of the grid mesh 10 overlap. In any case, the extensions overlap 13a . 13b in the compressed state of the lattice mesh 10 ,

As in 12a further recognizable, each mesh comprises 14 of the lattice braid 10 a total of four widenings 13 , being in the loop 14 two first extensions 13a two opposite extensions 13 extend. The other two extensions 13 have two second extensions 13b on, referring to the related stitch 14 extend. At the in 12a shown configuration, with two first extensions 13a opposite in a common mesh 14 extend, that will reach the length of the mesh 14 or the free opening length of the mesh 14 is reduced. This will increase the stability of the grid mesh 10 increased overall. It is also possible that a mesh 14 more than two first extensions 13a assigned. Alternatively, anyone can mesh 14 a single first extension 13a be assigned. In general, the first extensions 13a according to 12a and 12b tongue-like or form tongues, each in a mesh 14 protrude. The first extensions 13a or tongues facing the second extensions 13b due to their geometric extension a higher flexibility. Therefore, the asymmetric design of the broadening 13 the introduction of a coil catheter through the mesh 14 facilitated. The second extensions 13b that have a smaller width than the first extensions 13 may include the sliding of the first extensions 13a when compressing the mesh 10 over the other wire elements 11 . 12 favor. In particular, the second extensions 13b be curved radially inward so that the first extensions 13a in the compression of the lattice mesh 10 over the inwardly curved second extensions 13b easy on the wire elements 11 . 12 can slide.

Alternatively it can be provided that the widenings 13 only first extensions 13a or in each case a single extension 13a exhibit. Such a configuration is exemplary in FIG 13a and 13b shown. 13a shows a section of a grid mesh 10 with several first and second wire elements 11 . 12 , each with several extensions 13 include. The broadening 13 comprise a single extension 13a , which is unilaterally of the respective wire element 11 . 12 in a mesh 14 extends into it. The extension 13a covers the mesh 14 in large part. The extensions 13a are oriented substantially in the same circumferential direction. The circumferential direction is in 13a indicated by an arrow labeled UR. In other words, the extensions indicate 13a each have a peripheral component, wherein the peripheral component of all extensions 13a is identical. In general, the grid can be 10 a circumferential segment 23 having, by circumferentially immediately adjacent mesh 14 is formed. All extensions 13a the broadening 13 of the perimeter segment 23 point in the same circumferential direction. In particular, it can be provided that the first extension 13a larger than the second extension 13b is trained. The larger first extensions 13a a circumferential segment or the entire grid mesh 10 have preferably in the same direction, in particular circumferential direction, the opposite direction to the circumferential direction of the smaller, second extensions 13b is oriented.

Furthermore, the only extensions 13a the broadening 13 an axial component or are oriented in an axial direction, wherein in the embodiment according to 13a the axial components directly in the circumferential direction of adjacent extensions 13a are different. In particular, the extensions 13a of the perimeter segment 23 each oriented alternately in different axial directions. The axial direction of the mesh braid 10 is in the 13a and 13b indicated by the arrow marked AR.

When compressing the mesh braid 10 according to 13a results in the overlapping of the extensions characterized by the curved arrows 13a , In the compressed state thus creates two axial sections of the peripheral segment 23 wherein a first axial portion of the circumferential segment 23 all overlapping extensions 13a of the perimeter segment 23 includes. A second axial section of the circumferential segment 23 is through sections of the wire elements 11 . 12 formed, which no extensions 13a or broadening 13 include.

In the embodiment according to 13b On the other hand, it is provided that the extensions 13a a perimeter segment 23 of the lattice braid 10 are oriented in the same axial direction. It is particularly preferred, when the same axial direction is aligned in the distal direction relative to a delivery system of the medical device, for the supply of a coil catheter through the mesh 14 of the lattice braid 10 through. When transferring the grid mesh 10 according to 13b from the expanded to the compressed state, an overlap of the extensions takes place 13a the broadening 13 as shown by the curved arrows in 13b shown. In the compressed state of the mesh braid 10 has the circumferential segment 23 projections 13a on, with each extension 13a each a portion of a wire element 11 . 12 overlaps, no broadening 13 having. In other words, in the compressed state of the lattice mesh 10 in the circumferential segment 23 each between two overlapping extensions 13a a free wire element section arranged in the circumferential direction, no broadening 13 having.

The superimposition gliding of the extensions 13a . 13b when compressing the mesh 10 can be favored by a corresponding manufacturing process. 8a . 8b . 8c show a section of the grid structure 10 according to 2 , where at least part of the widening 13 on protrusions 24 a braiding mandrel (not shown for reasons of clarity) is arranged. This will ensure that these are on the protrusions 24 arranged widenings 13 be arranged in a different circumferential plane, in particular radial distance outside than the rest, not on projections 24 arranged widenings 13 , When compressing the mesh braid 10 according to 8a is achieved by the increased broadening 131 over the lower broadening 132 slide. It is advantageously provided that the braiding mandrel for producing the increased broadening 131 having substantially rectangular projections having a width between the longer side edges, at least the width of the widenings 13 equivalent. Preferably, the projections 24 of the braiding mandrel arranged such that in the axial direction of the mesh braid 10 each series of increased broadening 131 form. The braid can, as in 8a represented, each a projection 24 per increased broadening 131 exhibit. Alternatively, the braid mandrel may have axially extending elongate substantially rib-like projections each having a plurality of raised extensions 131 record as in 8b shown.

Alternatively it can be provided that the braiding mandrel several projections 24 each having an increased broadening 131 assigned. In this case, the projections 24 be arranged so spirally distributed over the braiding mandrel that, for example, only the broadening 13 the first wire elements 11 or just the broadening 13 the second wire elements 12 to increased broadening 131 be formed. This configuration is in 8c shown. In all three embodiments according to 8a - 8c overlap the increased broadening 131 in the compressed state, the lower widenings 132 , The overlap of the widenings indicated by the curved arrows 13 in the compressed state of the lattice mesh 10 can also arise if the grid mesh 10 on a wicker thorn without protrusions 24 is made. The overlap of the broadening 13 or at least the extensions 13a . 13b the broadening 13 can also be caused by a bending or curvature of the widenings or torsion of the corresponding wire elements 11 . 12 respectively.

The following are preferred dimensions for the individual elements of the grid mesh 10 the medical device according to the invention indicated:
The wall thickness of the band-shaped wire elements 11 . 12 may preferably be at most 100 μm, in particular at most 80 μm, in particular at most 60 μm, in particular at most 40 μm, in particular at most 30 μm, in particular at most 20 μm, in particular at most 15 μm, in particular at most 10 μm. If the broadening 13 a smaller wall thickness or height than the associated wire element 11 . 12 has a broadening height or broadening wall thickness of at most 30 .mu.m, in particular at most 20 .mu.m, in particular at most 10 .mu.m, in particular at most 5 microns, is advantageous.

The rotationally symmetrical grid mesh 10 is preferably compressible in such a way that it can be introduced into a delivery system or a catheter having an inner diameter of at most 2 mm, in particular at most 1.6 mm, in particular at most 1.4 mm, in particular at most 1.2 mm, in particular at most 1.0 mm, in particular at most 0.9 mm, in particular at most 0.8 mm, in particular at most 0.7 mm, in particular at most 0.6 mm, in particular at most 0.5 mm, in particular at most 0.4 mm, is insertable.

The wire elements 11 . 12 can outside the broadening 13 have a width which is preferably at most 200 .mu.m, in particular at most 150 .mu.m, in particular at most 120 .mu.m, in particular at most 100 .mu.m, in particular at most 80 .mu.m, in particular at most 60 .mu.m, in particular at most 50 .mu.m, in particular at most 40 .mu.m. The broadening 13 on the other hand can have a width which is at least 100 μm, in particular at least 150 μm, in particular at least 200 μm, in particular at least 300 μm, in particular at least 500 μm, in particular at least 800 μm, in particular at least 900 μm, in particular at least 1 mm, in particular at least 1, 2 mm, in particular at least 1.5 mm, in particular at least 2.0 mm, in particular at least 2.5 mm, in particular at least 3.0 mm.

The wire element 11 . 12 preferably in the area of rejuvenation 18 in the top 17 an end loop 16 a width which is at most 20 μm, in particular at most 10 μm, in particular at most 5 μm.

At the crossroads 15 can the wire elements 11 . 12 , in particular the first wire element 11 have a ratio between width and height or thickness which is at least 1.2, in particular at least 1.4, in particular at least 1.6, in particular at least 1.8, in particular at least 2.0, in particular at least 2.5, in particular at least 3 , 0, in particular at least 3.5, in particular at least 4.0, in particular at least 4.5, in particular at least 5.0, in particular at least 5.5, in particular at least 6.0, in particular at least 7.0, in particular at least 8.0 , in particular at least 9.0, in particular at least 10, in particular at least 12, in particular at least 15, in particular at least 20, in particular at least 25, in particular at least 30, in particular at least 35, in particular at least 40 amounts to.

The ratio between the width of the broadening 13 and the width of the wire element 11 at the crossroads 15 is preferably at least 1.2, in particular at least 1.5, in particular at least 2.0, in particular at least 3.0, in particular at least 4.0, in particular at least 5.0, in particular at least 6.0, in particular at least 7.0, in particular at least 8.0, in particular at least 9.0, in particular at least 10, in particular at least 12, in particular at least 15, in particular at least 20, in particular at least 25, in particular at least 30, in particular at least 35, in particular at least 40.

The upper limit for the above ratios may each be, for example, 50, in particular 45 or less. Other smaller upper limits are possible.

Overall, the grid mesh preferably has a closed peripheral surface, ie by wire elements 11 including broadening 13 covered peripheral surface, on, which is smaller than the total area, including the opening area of the mesh 14 , is. In particular, the grid mesh 10 preferably a closed peripheral surface, the at least 20%, in particular at least 30%, in particular at least 40%, in particular at least 50%, in particular at least 60%, in particular at least 70%, in particular at least 80%, in particular at least 90%, of the total area of the lattice mesh 10 accounts.

A single broadening 13 preferably has an area of at least 0.01 mm ² , in particular at least 0.05 mm ² , in particular at least 0.1 mm ² , in particular at least 0.2 mm ² , in particular at least 0.3 mm ² , in particular at least 0.5 mm ² , in particular at least 0.8 mm ² , in particular at least 1 mm ² , in particular at least 1.2 mm ² , in particular at least 1.5 mm ² , in particular at least 2 mm ² , in particular at least 2.5 mm ² , in particular at least 3 mm ² , in particular at least 3.5 mm ² , in particular at least 4 mm ² , on.

The grid 10 may be at least 2, in particular at least 4, in particular at least 6, in particular at least 8, in particular at least 10, in particular at least 12, in particular at least 16, in particular at least 20, in particular at least 24, in particular at least 32, in particular at least 36, in particular at least 40, in particular at least 48 , Wire elements 11 . 12 include.

The medical device, in particular the grid mesh 10 , is preferably adapted to allow treatment of body vessels having a cross-sectional diameter of at least 1 mm and at most 30 mm. For comparatively small body vessels, a cross-sectional diameter of the lattice braid is 10 not more than 8 mm, in particular not more than 6 mm, in particular not more than 5 mm, in particular not more than 4.5 mm, in particular not more than 4.0 mm, especially not more than 3.5 mm, especially not more than 3.0 mm, in particular not more than 2.5 mm, in particular at most 2.0 mm, in particular at most 1.5 mm, advantageous. The cross-sectional diameter of the grid mesh 10 for use in comparatively larger body vessels is preferably at least 2.0 mm, in particular at least 3.0 mm, in particular at least 4.0 mm, in particular at least 5.0 mm, in particular at least 6.0 mm, in particular at least 8.0 mm, in particular at least 10.0 mm, in particular at least 12.0 mm, in particular at least 15.0 mm, in particular at least 20.0 mm. The aforementioned dimensions apply to the manufacturing state of the grid mesh 10 ,

The production of the lattice mesh 10 or the wire elements 11 . 12 takes place advantageously by a forming process, for example by drawing or flat rolling, wherein the profiling or broadening 13 subsequently formed by laser cutting. Preferably, the wire elements 11 . 12 made of a rolled flat strip, wherein from the flat strip, the shape of the wire element 11 . 12 including the broadening 13 is cut out by laser cutting or a punching process. Alternatively, the wire element 11 . 12 including broadening 13 by roll forming or a thin film process, in particular a sputtering process or a combined sputtering etching process. When using a thin-film method, it is also possible to form recesses in relation to the material thickness or the wall thickness, for example by the total wall thickness of the mesh in the region of the crossing points 15 or the widening 13 to reduce.

Preferred materials for the wire elements 11 . 12 and the broadening 13 Advantageously, in one piece or in one piece with the wire element 11 . 12 is formed, shape memory materials, in particular shape memory metals or shape memory plastics. For example, the wire element 11 . 12 be made of a nickel-titanium alloy. The nickel-titanium alloy may additionally comprise further alloying additives, for example chromium, platinum, niobium, palladium or the like. Furthermore, the use of so-called cobalt-chromium alloys, for example ELGILOY, PHYNOX or the like is possible. The wire elements 11 . 12 may also include titanium or titanium alloys, platinum or platinum alloys, tantalum or tantalum alloys, and magnesium alloys, especially with zinc and / or calcium alloy components. The wire elements 11 . 12 may also comprise a plastic, in particular a polymer, preferably a shape memory polymer.

The medical device can be used as a stent or flow diverter to influence the flow in the area of aneurysms. Alternatively, a use as a stenosis stent or for the treatment of plaque is possible, wherein the filtration effect of the mesh according to the invention 10 can be used particularly advantageous. For the treatment of aneurysms, it is advantageous to use the mesh 10 only in a middle area with widening 13 equip so that the axial ends of the grid mesh 10 have a higher fluid permeability. In the arrangement of the mesh braid 10 In the region of vessel branches, it is thus ensured that the branching vessels are adequately perfused with a body fluid, in particular blood.

Alternatively, the medical device can be used as a filter, in particular as a temporary filter. The rotationally symmetrical grid may therefore not only have a cylindrical or tubular structure, but also, for example, a conical or truncated cone-shaped structure. In particular, it is possible that all free wire ends are connected to one another at one axial end of the grid mesh. The connection can be made by twisting, welding or by crimping with sleeves. In this way, a basket-like shape of the medical device is essentially produced. By the broadening 13 in the grid 10 the efficiency of the filtration is increased, since the flow-through surface portion of the basket or the grid mesh 10 is relatively small. In other words, the basket protects through the widenings 13 and thus largely closed wall of the grid mesh 10 before distal embolism. The medical device can be positioned during the treatment of a stenosis, for example in the region of the carotid artery, distal to the treatment site. In this case, the medical device, in particular the grid mesh 10 proximally fixed or releasably connected to a guide wire.

The grid 10 In general, the medical device may be connected to a guidewire in a releasable or detachable manner, so that it is possible to use the medical device for a limited time.

LIST OF REFERENCE NUMBERS

10, 10 '

wickerwork

11, 11 '

first wire element

12, 12 '

second wire element

13

widening

13a

first extension

13b

second extension

14

mesh

15, 15 '

intersection

16

end loop

17

top

18

rejuvenation

19

perforation

20

rivet

21

side surface

21a

first side surface

21b

second side surface

23

peripheral segment

24

head Start

131

increased broadening

132

lower broadening

Claims (19)

Medical device, in particular stent, having a rotationally symmetrical grid ( 10 ) which can be converted from a radially compressed state into a radially expanded state and at least one first wire element ( 11 ), forming at least one crossing point ( 15 ) with at least one second wire element ( 12 ), wherein at least the first wire element ( 11 ) is band-shaped and at least one broadening ( 13 ), which from the crossing point ( 15 ) is arranged at a distance. Medical device according to claim 1, characterized in that the first wire element ( 11 ) has a cross-sectional profile with a width and a height, wherein the width is greater than the height, which is substantially the wall thickness of the mesh ( 10 ) certainly. Medical device according to claim 1 or 2, characterized in that the broadening ( 13 ) between two immediately adjacent crossing points ( 15 ), the crossing points ( 15 ) on the one hand by the first wire element ( 11 ) and on the other hand by the second wire element ( 12 ) or another wire element are formed. Medical device according to one of claims 1 to 3, characterized in that the broadening ( 13 ) at least partially into a mesh ( 14 ) of the mesh braid ( 10 ). Medical device according to one of claims 1 to 4, characterized in that the first wire element ( 11 ) has substantially a non-round, in particular quadrangular, cross-sectional profile. Medical device according to one of claims 1 to 5, characterized in that the broadening ( 13 ) at least one extension ( 13a . 13b ) which extends across the width of the first wire element ( 11 ) protrudes and is flap-like radially deflectable. Medical device according to claim 6, characterized in that the extension ( 13a . 13b ) on one side of the first wire element ( 11 ) or broadening ( 13 ) at least two extensions ( 13a . 13b ), which on both sides of the wire element ( 11 ) go out. Medical device according to claim 6 or 7, characterized in that the extension ( 13a . 13b ) a smaller height than the first wire element ( 11 ) having. Medical device according to one of claims 1 to 8, characterized in that the broadening ( 13 ), in particular the extension ( 13a . 13b ) along an outer circumference or along an inner circumference of the lattice braid ( 10 ). Medical device according to one of claims 1 to 9, characterized in that the broadening ( 13 ), in particular the extension ( 13a . 13b ), radially inwardly or radially outwardly bendable or twistable. Medical device according to one of claims 6 to 10, characterized in that the extension ( 13a . 13b ) in the compressed state, at least the second wire element ( 12 ) or another wire element overlaps. Medical device according to one of claims 6 to 11, characterized in that the extension ( 13a . 13b ) in the expanded state of the mesh ( 10 ) at least one mesh ( 14 ) of the mesh braid ( 10 ) overlaps. Medical device according to one of claims 1 to 12, characterized in that a plurality of band-shaped first wire elements ( 11 ) each having at least one broadening ( 13 ) exhibit. Medical device according to claim 13, characterized in that the widenings ( 13 ), in particular the extensions ( 13a . 13b ), in the compressed state of the mesh ( 10 ) overlap. Medical device according to one of claims 1 to 14, characterized in that the broadening ( 13 ) asymmetrically with respect to a longitudinal extension of the first wire element ( 11 ) is formed such that a first extension ( 13a ) of broadening ( 13 ) further over the width of the first wire element ( 11 ) protrudes as a second extension ( 13b ) of broadening ( 13 ). Medical device according to one of claims 1 to 15, characterized in that the grid mesh ( 10 ) at least one circumferential segment ( 23 ) from immediately adjacent meshes ( 14 ), wherein at least a part of the mesh ( 14 ), in particular all meshes ( 14 ), the perimeter segment ( 23 ) at least one broadening ( 13 ) assigned. Medical device according to claim 16, characterized in that in each case the first extensions ( 13a ) of the widening ( 13 ) of the peripheral segment ( 23 ) are oriented substantially in the same circumferential direction such that the widenings ( 13 ) in the compressed state of the mesh braid ( 10 ) overlap like scales. Medical device according to claim 17, characterized in that the first extensions ( 13a ) in the compressed state of the mesh braid ( 10 ) the second extensions ( 13b ) overlap. Medical device according to claim 17 or 18, characterized in that the first extensions ( 13a ) are oriented in the same axial direction.

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