DE102018107594A1 - Medical device for intravascular treatment - Google Patents

Abstract

Medical device for intravascular treatment with an at least partially tubular lattice structure (10) of integrally connected webs (11) delimiting cells (12), wherein four webs (11) by a web connector (13) are interconnected, wherein at least one X-ray visible Wire element (20, 20 ') is provided which is guided along at least one web (11) and in one end portion (10b) of the lattice structure (10) has a loop (21, 21') with a first leg (22a, 22a ') and a second leg (22b, 22b '), wherein the first leg (22a, 22a') and the second leg (22b, 22b ') radially within the lattice structure (10) or the first leg (22a, 22a') and the second leg (22b, 22b ') are arranged radially outside the grid structure (10).

Description

The invention relates to a medical device for intravascular treatment according to the preamble of claim 1. A medical device of this kind is for example made DE 10 2014 115 533 A1 known.

Thrombectomy devices, also referred to as stent retrievers, consist of a tubular lattice structure in which ridges bound individual cells. Such lattice structures are typically laser cut from a shape memory material such as Nitinol. The proximal end of the grid structure is connected to a transport wire. An example of such a thrombectomy device is off WO 2012/106657 A2 known. To improve the radiopacity of the thrombectomy device, X-ray visible wires are guided along the bars of the grid structure. The wires loosely wrap around the bars, while constructively preventing the wires from moving or even loosening during use of the thrombectomy device. Particularly problematic is the positioning of the device, in particular the retraction into the catheter when the thrombectomy device is to be repositioned. The wires may block the compression of the grid structure when the radiopaque wire overlaps unfavorably with the grid structure.

The aforementioned medical device according to DE 10 2014 115 533 A1 solves this problem in that the wires form loops at the proximal end of the grid structure, the web connectors arranged between the webs engage around in such a way that the wires are fixed longitudinally axially. This improves the safety in positioning as well as the attachment of the wires to the grid structure. It has been shown that relatively large forces are required for the compression of such thrombectomy devices.

The invention is based on the object to improve a medical device of the type mentioned in that the lattice structure of the device can be compressed relatively easily, without affecting the reliability of the device is impaired.

According to the invention, this object is achieved by a medical device having the features of claim 1. Specifically, the object is achieved by a medical device for intravascular treatment, in particular for the removal of thrombi, with an at least partially tubular grid structure having integrally connected webs. The webs define cells, wherein three or four webs are connected by a web connector. At least one radiopaque wire element is provided, which is guided along at least one web and forms a loop with a first leg and a second leg in one end section of the lattice structure.

According to the invention, it is provided that the first leg and the second leg are arranged radially inside the lattice structure. Alternatively, the first leg and the second leg are arranged radially outside the grid structure.

The loop consists of two legs and a loop bend that connects the two legs. As a leg, the wire section is to be understood in the immediate vicinity of the loop bend. The leg has a length which extends at least to the first crossover with a web. In other words, both legs are arranged at least up to and including the first crossover with a web on the same side (radially inward or radially outward) of the grid structure. The two legs cross different webs in the area of the first crossover.

The legs are thus decoupled from the grid structure that the grid structure is not hindered by the wire element during compression. It is understood that the legs of the loop after the first crossover at least over a certain distance on the same side (radially inside or radially outside) of the grid structure are arranged or can be.

As the lattice structure continues, the wire element alternates the side of the lattice structure, i. from radially inward to radially outward or vice versa. For example. the change can take place in the region of the proximal end of the end cell. The change can be made even further proximal, for example in the region of a further cell adjacent to the end cell.

The wire element can then go into turns along the webs.

The legs include an angle determined by the loop bow. The loop and the legs are always arranged on the same radial side of the grid structure.

The invention allows a certain relative movement between the wire element and the lattice structure, so that the movement of the cells during compression or expansion in the circumferential and longitudinal direction of the lattice structure takes place as undisturbed as possible. The same applies to the effect of foreshortening, in which the total length of the lattice structure during compression or expansion changes. The arrangement of the two legs radially within the grid structure or radially outside the grid structure, a mechanical decoupling of the wire element is achieved by the grid structure in the region of the distal end portion of the grid structure. As a result, a relative movement between the grid structure and the wire element is possible in this area.

Due to the decoupled arrangement of the wire element in a specific region of the lattice structure, namely in the region of the end portion, it is also achieved that the remaining region of the lattice structure and the wire element can be connected relatively tightly, at least so tightly that the security against slippage of the wire element relative to the lattice structure is substantially maintained. In any case, it is possible to make the connection between the wire element and the grid structure so that the functionality of the device is maintained, without the ease of the device is compromised during compression.

The decoupling is limited to the area of the loop. The loop may, for example, extend to the first crossover.

In a preferred embodiment, the loop is substantially stress-free by heat treatment in the expanded state of rest of the device, i. There are no residual stresses.

The invention is applicable, for example, to the applicant's manufactured stent retriever with the trade name APERIO, whose basic structure in the granted patent DE 10 2014 115 533 B1 the applicant is described in more detail. The invention is explicitly disclosed and claimed in connection with this device. This known thrombectomy device is suitable for rapid recanalization and has a hybrid cell design. This achieves excellent wall apposition and thrombus integration. The attachment of the radiopaque wire element to the grid structure of the stent retriever is readily possible. The hybrid cell design includes small closed cells that provide excellent apposition to the vessel wall as well as safe uptake of thrombi. Compared to this, larger cells with integrated anchoring elements ensure effective retention of thrombi as well as safe, atraumatic removal.

The connection of four webs by a web connector does not exclude that the grid structure has web connectors which connect less than four webs, for example three webs. In a hybrid cell with different cells, normal cells can be formed by bar connectors with four main bars and sub-cells by bar connectors with three bars.

The invention is also applicable to other thrombectomy devices.

In general, the medical device designed according to the invention can form an implant, for example a stent, or a temporary instrument, such as the thrombectomy device described above.

In general, it should be noted that the medical device has a tubular grid structure that is radially expandable. In this case, the tubular grid structure can be automatically transferred, for example by utilizing the shape memory effect, from a radially compressed to a radially expanded state. In this respect, the medical device preferably has a self-expanding lattice structure.

The grid structure may be formed, for example, in sections or completely tubular.

In a preferred embodiment of the medical device as a thrombectomy device, it can be provided in a preferred manner that the lattice structure section is tubular, wherein the tubular shape merges into a funnel-shaped or conical section at a proximal end of the lattice structure. The conical section forms a transition of the lattice structure into a catheter in which, in use, the device extends in the compressed state. The conical section has the function to enable the recoverability. The advantage manifests itself in the compressed state of the device. Due to the radially outwardly or radially inwardly disposed limbs of the wire elements or the loop arranged inside or outside, there is a relative freedom of movement between the radiopaque wires and the lattice structure. As a result, the stresses in the catheter are reduced and a lower supply force for reinsertion into the catheter is required. Especially in the axial direction, the relative mobility of advantage, since it is assumed that the loop moves in this direction and their position in the. In and out varies.

The invention is not limited to a thrombectomy device but also encompasses other medical devices.

The term "distal" means a side facing away from the user device or remote side of the grid structure. The term "proximal" means a user-facing side of the medical device, ie, a side closer to the user.

Preferred embodiments of the invention are specified in the subclaims.

In a preferred embodiment, the end portion is a distal end portion. This has the advantage that the relative freedom of movement between the loop and the grid structure is favored.

Thus, for example, the loop may be arranged in an expanded state of the lattice structure between two circumferentially adjacent distal end cells of the lattice structure. Alternatively, the loop may be disposed in an expanded state of the lattice structure within a distal end cell of the lattice structure. For multiple wire elements both alternatives can be combined. As a result, a pattern or a distribution of the loops on the circumference of the lattice structure is achieved precisely in the case of a plurality of wire elements having a corresponding number of loops, so that a compression or expansion of the lattice structure which is as unimpeded as possible is possible.

The arrangement of the two legs radially inside or radially outside the grid structure is possible in both variants (within a distal end cell and between two adjacent distal end cells).

The invention does not exclude that in use of the device may result in a displacement in the radial direction, so that the loop is slightly offset inwards. In the resting state or generally in the expanded state, the two legs are arranged radially inside or radially outside of the lattice structure. In the expanded state, a distinction with respect to the position of the legs or the loop is still possible. However, in particular in the compressed state, no precise assignment of the legs or the loop to the cells can take place.

In the above embodiment, in which the loop is disposed between two circumferentially adjacent distal end cells, the first leg and the second leg may be passed through one of the end cells, respectively. As a result, the inner or outer loop is supplied to the grid structure over a relatively short distance, so that, apart from the distal end section, a good fixation of the wire element to the grid structure is possible.

Preferably, in an expanded state of the lattice structure, the loop is distally disposed from a distal web connector of the lattice structure, in particular at least one land width, preferably at least 25% of a land length, more preferably at least 50% of a land length. This embodiment supports the free mobility of the grid structure in the region of the distal end portion because the distance between the loop and the distal bar connector allows a free distance along which the grid structure and the wire element can move relative to one another.

Preferably, the loop divides the wire element into a first section and a second section. The first section and / or the second section wind around a plurality of webs, each forming a web row aligned with each other. The web row runs helically around a longitudinal axis of the lattice structure. Thereby, a corresponding pattern is achieved by the wire element or a corresponding course of the wire element, which ensures a particularly good visibility or visibility.

In a preferred embodiment, the wire element is wound around a row of webs such that the wire element reaches a full turn, in particular a turn through 360 ° along the web row to a web, in particular to 2 webs, in particular to 3 webs.

The wire element may be formed by a fully X-ray visible wire or a composite wire with a radiopaque core. The latter is known, for example, by the term DFT wire and has the advantage that good biocompatibility of the wire element is associated with the function of the radiopacity.

In order to improve the radiopacity, 2, 3 or 4 wire elements can be provided, each of which forms a loop in the distal end section of the lattice structure. According to the invention, the loop is in each case formed in such a way that the first and second limbs of the loop are arranged radially inside the lattice structure or radially outside the lattice structure.

In a further embodiment, the sections of the wire elements may intersect regularly along the grid structure, wherein at least two, in particular at least three and at most eight, in particular at most six webs of a web row are arranged between two crossing points. As a result, the pitch of the wire element along the grid structure or along a central axis of the grid structure can be influenced. In a preferred embodiment, exactly three webs of a web row are arranged between two crossing points.

In a further preferred embodiment, at most four loops each having a first leg and a second leg are arranged in a distal end section of the lattice structure. The first leg and the second leg are arranged radially inside or radially outside the lattice structure.

The grid structure may have at least one web extension at a proximal end section, which is connected in a form-locking manner to a distal coupling piece of a transporting wire. Preferably, two web extensions are provided. As a result, a secure connection of the grid structure is created with the transport wire. This embodiment is particularly well suited as a thrombectomy device.

The web extension can have an engagement element which engages precisely in a recess of the coupling piece, which extends transversely to a longitudinal axis of the transport wire. As a result, the axial forces occurring when moving the device in a feeding system are safely transmitted.

For further security, a crimping sleeve can be provided, which surrounds the web extension and the coupling piece.

A particularly good fixation of the wire element to the grid structure is achieved in that the open ends of the wire elements are passed through the crimp sleeve, that the open ends of the wire elements ideally close to approximately flush with the proximal end of the sleeve or just so far from the protrude proximal end to be fully glued. This ensures that the wire element is held securely at the proximal end or region of the transport wire.

The protruding wire end may be connected to the transport wire by, for example, an adhesive-filled coil, the coil enclosing the protruding wire end and the transport wire. As a result, further security against unintentional release of the thrombectomy device from the transport wire is achieved.

Alternatively, the protruding wire end may be glued directly to the transport wire.

In the context of the invention, a method for producing a medical device according to the invention is further disclosed and claimed. The method comprises the heat treatment of at least one wire element, so that the wire element is largely stress-free in the expanded or partially expanded state. In particular, the loop of the wire element can thus be moved and recovered with a lower supply force in the catheter. The wire element and thus the loop want to go into their expanded state after reaching the transformation temperature. Below this temperature, the grid structure can be compressed stress-free, by re-drawing into the catheter.

The invention will be described in more detail below with reference to an embodiment with reference to the accompanying schematic figures with further details.

• 1 eine medizinische Vorrichtung nach einem erfindungsgemäßen Ausführungsbeispiel, wobei die Gitterstruktur in einem flach ausgebreiteten Zustand dargestellt ist;
• 2 eine Detailansicht der Vorrichtung nach Anspruch 1 im Bereich des distalen Endabschnitts;
• 3 eine perspektivische Ansicht des Transportdrahts mit dem Kopplungsstück;
• 4 eine perspektivische Ansicht des Transportdrahts nach 3 mit eingelegtem Stegfortsatz und einer halbdurchsichtig gezeichneten Crimphülse (Zwischenmontagezustand);
• 5 der Transportdraht nach 3 mit Drahtelementen (Zwischenmontagezustand);
• 6 der Transportdraht nach 3 im finalen Montagezustand;
• 7 ein alternatives Ausführungsbeispiel des Transportdrahtes.

In this show

• 1 a medical device according to an embodiment of the invention, wherein the grid structure is shown in a flat spread state;
• 2 a detail view of the device according to claim 1 in the region of the distal end portion;
• 3 a perspective view of the transport wire with the coupling piece;
• 4 a perspective view of the transport wire after 3 with inserted web extension and a semi-transparent drawn crimp sleeve (intermediate mounting state);
• 5 the transport wire after 3 with wire elements (intermediate mounting state);
• 6 the transport wire after 3 in the final installation condition;
• 7 an alternative embodiment of the transport wire.

1 shows in a flat spread illustration a medical device with a grid structure 10 from cells 12 consisting of several, integrally connected webs 11 are formed. For illustration purposes was in 1 resorted to an unfolded view in which the lattice structure 10 shown cut longitudinally and spread flat. It is understood that the lattice structure 10 is actually tube-shaped. The tube shape results from the fact that the lattice structure 10 is cut from a tube material, in particular laser cut. Other geometries of the grid structure are always possible and explicitly mentioned in the introduction to the description. Besides laser cutting, other manufacturing methods are possible.

In 1 is shown a hibernation in which the grid structure 10 no external forces act. In the compressed state, the webs are 11 close to each other, so that a smaller cross-sectional profile for the lattice structure 10 results. The Stege 11 limit cells 12 , It is provided that at least partially each four webs 11 a cell 12 limit. The bridges 11 form a rhombic cell 12 or a cell 12 with a diamond-shaped basic structure (closed cell design).

The bridges 11 , each one cell 12 limit, are interconnected by bar connectors 13 coupled. From every bridge connector 13 go four bars each 11 out. The bridge connectors 13 are each integral with the webs 11 in the grid structure 10 integrated. Essentially, the bridge connectors form 13 Cross points of the bridges 11 , Every jetty 11 forms a direct connection between two bar connectors 13 , The bridge connectors 13 are preferably patterned across the grid structure 10 arranged distributed. The bridges 11 may have the same or different web widths.

It can be provided that each two opposite, mutually parallel webs can have the same web width. The parallel opposite webs 11 each form a pair of bridges, with the bridge width of the webs 11 the web pairs of a cell 12 can differ from each other. In other words, every cell points 12 a first pair of bars and a second pair of bars, wherein the webs 11 the first pair of webs a different web width than the webs 11 of the second pair of webs have. Such a designed cell is called an asymmetric cell. The formation of the lattice structure 10 Asymmetric cells increase the bending flexibility of the lattice structure so that the medical device can be used well in curved blood vessels.

The ridge widths vary between 30 .mu.m and 60 .mu.m, preferably between 36 .mu.m and 54 .mu.m. In the proximal end region 10a are the bars 11 up to 90 μm wide. The wall thickness is between 60 μm and 100 μm.

The invention is not limited to a lattice structure with symmetrical cells, but can also be used for lattice structure with asymmetric cells.

The grid structure 10 has a hybrid cell design with a multitude of small closed cells 12 and compared to the small cells 12 larger cells 12c on. The small cells 12 allow a good apposition of the lattice structure 10 to the vessel wall. The bigger cells 12c have integrated anchoring elements 12d which, in use, effectively retain the thrombus to be removed and provide safe, atraumatic removal of the thrombus. There are also conceivable applications in which no hybrid cell design is necessary and the anchoring elements 12d can be omitted.

As in 1 To recognize well, the device has at least one wire element 20 , in concrete terms, two wire elements 20 . 20 ' on. It is possible that more than two wire elements are provided, for example a total of 3 or 4 wire elements, which are arranged distributed pattern-like on the circumference.

The wire element or the wire elements are formed from a radiopaque material. For example, it can be a solid material made of a radiopaque material. It is also possible to use a composite material, for example so-called DFT wire elements. Such wire elements comprise a core wire of a radiopaque material, such as platinum, tantalum or gold, and a shell of a shape memory material. An example of a DFT wire element has a platinum core of 40-60 μm in diameter and a Nitinol jacket whose outside diameter corresponds to the core diameter plus about 20 μm. Also conceivable would be other materials and varied dimensions or only a radiopaque wire without superelastic coat.

In general, all radiopaque materials commonly used for implants can be used.

As in 1 to recognize forms the wire element 20 a loop 21 located in the area of the distal end section 10b the lattice structure 10 is arranged. The distal end section 10b forms the axial end of the tubular lattice structure 10 which first exits a catheter when the device is deflated.

In the area of the loop 21 changes the wire element 20 its direction in such a way that the wire element from the lattice structure 10 is brought in and out again. The loop 21 has a first leg 22a and a second leg 22b on, which extend at an angle to each other. Between the two thighs 22a . 22b forms the wire element 20 a curved section that holds the two legs 22a . 22b combines.

In the starting example according to 1 are two wire elements 20 . 20 ' provided, which are each constructed accordingly. The second wire element 20 ' has accordingly two legs 22a ' . 22b ' up, the second loop together 21 ' form. The two loops 21 . 21 ' are essentially identical. The following statements in connection with the first loop 21 apply accordingly for the second loop 21 ' ,

The two thighs 22a . 22b the first loop 21 are radially inside the lattice structure 10 arranged. In the example according to 1 this means that the two thighs 22a . 22b in the picture plane behind the grid structure 10 are arranged. It is possible that the two thighs 22a . 22b are arranged radially outside the grid structure. This corresponds to an embodiment in which the in 1 shown leg 22a . 22b in the picture plane in front of the grid structure 10 are arranged.

Specifically, the first loop 21 in the area of end cells 12 . 12a . 12b that is, in the axially outermost row of cells of the lattice structure 10 arranged. Here are the two thighs 22a . 22b the first loop 21 through the end cells 12 . 12a . 12b guided in the same direction and are in the range of the end portion 10b both on one and the same side of the grid structure 10 , A fixation of the wire element 10 through the loop is thereby in the region of the end portion 10b avoided. The loop 21 can be essentially free based on the lattice structure 10 move. The loop 21 is characterized by the lattice structure 10 decoupled.

On top of that, the loop 21 , specifically the area in which the loop 21 the direction changes, from the distal bar connector 13b is spaced. The distal bar connector 13b is the in the axial direction at the outermost arranged web connector 13 ,

The loop 21 stands over the adjacent end cells 12a . 12b something in the axial direction. It is enough if the loop 21 loose in front of the distal bar connector 13b is arranged, since the decoupling of the loop 21 from the grid structure 10 by the arrangement of the two legs 22a . 22b on one and the same side of the grid structure 10 he follows. By the spacing of the loop 21 from the distal bar connector 13 it is even better ensured that the loop 21 the movements of the lattice structure 10 not disabled. The loose arrangement of the loop bow may be slightly further in the proximal direction in the lattice structure 10 extend.

The distance between the distal bar connector 13b and the loop 21 At least 25% of a bridge length may be at least 50% of a bridge length. The maximum distance of the loop 21 from the distal bar connector 13b should not be more than the axial end of the lattice structure 10 be. In other words, the loop should be 21 not in the axial direction over the grid structure 10 , specifically about the free ends of the end cells 12 . 12a . 12b protrude.

In the example according to 1 is the loop 21 in the expanded state of the lattice structure 10 between two circumferentially adjacent distal end cells 12a . 12b arranged. In other words, the loop extends 21 at least in sections in the free space between the two adjacent end cells 12a . 12b is formed. Alternatively or additionally, the loop 21 be arranged inside a distal end cell (not shown), which also applies here, that the two legs of the loop 21 on one and the same side of the grid structure 10 are arranged.

At some distal end cells 12 . 12b the lattice structure 10 X-ray markers, for example three distal PtIr-dot markers can be arranged. In contrast to the prior art, the wire elements 21 . 21 ' in the region of the distal end section 10b not fixed by the x-ray markers.

Generally, the loops form 21 . 21 ' , free wire sections that stretch over the webs 11 the immediately adjacent end cells 12 A . 12 B extend beyond.

In the example according to 1 is the first thigh 22a through the in 1 left distal end cell 12a and the second leg 22b through the in 1 right distal end cell 12b guided in the same direction from the inside out, so that the entire loop 21 completely outside the lattice structure, ie radially outside the lattice structure 10 is arranged. Again, that is the decoupling of the loop 21 can also be done in the reverse direction, ie when the two legs 22a . 22b in the reverse direction, that is guided from outside to inside.

In the starting example according to 1 the fixation of the wire element takes place 20 outside the end section 10b , specifically from the immediate on the distal end cells 12 . 12a . 12b subsequent cell series. In other words, the distal row is the end cell 12 . 12a . 12b the area in which the wire element 20 or the loop 21 loose on the grid structure 10 is arranged. The scope of the loose arrangement of the clew 21 can get a little further into the grid structure 10 for example up to and including the second row of cells 12 extend. In order not to disturb the functionality of the grid structure, the loose arrangement of the loop should 21 limited to a distal area. The larger area of the lattice structure 10 serves to fasten the wire element 20 ,

The arrangement of the loop 21 radially inside the lattice structure 10 is in the in 2 illustrated detail view of the grid structure 10 particularly easy to recognize. It can be seen that the two thighs 22a . 22b from the grid structure 10 coming over the footbridges 11 the neighboring cells 12 are guided and in the distal end cells 12 . 12a plunge. The two thighs 22a . 22b are through the distal end cells 12a . 12b passed in the same direction, so that the two legs 22a . 22b both on the same side of the grid structure 10 , specifically arranged on the inside. The loop 21 is arranged radially inside and axially inside, ie that the grid structure ( 10 ) extends axially over the loop end.

For attachment is the wire element 20 partially into the lattice structure 10 interwoven and / or wrapped individual webs 11 the lattice structure 10 , Several wire elements 20 can independently with the grid structure 10 be intertwined and / or the individual webs 11 the lattice structure 10 wrap.

The wire element 20 can be substantially parallel or laterally along the webs 11 run. In general, the wire element extends 20 preferably along a bridge row 14 , which is formed by a plurality of webs arranged one behind the other. In 1 shows the reference numeral 14 provided arrow in the direction of the bridge row 14 , The bridge row 14 preferably runs helically around the longitudinal axis of the lattice structure 10 , From the bridge row 14 go sideways more webs 11 from, wherein the wire element 20 the laterally outgoing webs 11 can intersect or cross over. In this way, the wire element 20 safely in the grid structure 10 woven. In addition, the wire element 20 around the footbridges 11 the bridge row 14 wrap.

The wire element 20 gets through the distal loop 21 in two sections 23a . 23b divided. The two sections 23a . 23b can parallel to each other helically around the longitudinal axis of the lattice structure 10 be winding. It is also possible that the first section 23a and the second section 23b along different ridges 14 extend so that the first section 23a and the second section 23b in the longitudinal direction of the lattice structure 10 intersect once or several times. In 1 It is easy to see that the wire element 20 from the proximal end 10a to the distal end 10b is guided, there at a distal loop 21b deflected and into the grid structure 10 is traced back, crossed several times with itself.

If several wire elements 20 . 20 ' , in concrete terms, two wire elements 20 . 20 ' are provided, the respective first and second sections can 23a . 23a ' . 23b . 23b ' overlap, resulting in an overall diamond-shaped pattern of radiopaque wire elements (s. 1 , flat spread grid structure). Both wire elements 20 . 20 ' are helical on the perimeter of the lattice structure 10 arranged.

In the example according to 1 reaches the wire element 20 a full turn, in particular a turn of 360 °, after a bridge 11 wherein the winding is two adjacent webs 11 includes. A different number of webs, for example one or three webs is possible to complete a turn of the wire element 20 to reach. In other words, the number of windings decreases, the more webs for a complete turn of the wire element 10 along the bridge row 14 are provided.

The two sections 23a . 23a ' . 23b . 23b ' the wire elements 20 . 20 ' intersect along the lattice structure 10 in a regular pattern. In concrete terms, the wire elements intersect 20 . 20 ' in several crossing points 25 in the example according to 1 3 bars between 2 crossing points 25 along a bridge row 14 are arranged. Another number of webs, for example, two webs or more than three webs possible.

At the proximal end section 10a end the wire elements 20 . 20 ' with free wire ends 24 . 24 ' not in the grid structure 10 returned but at the outer edge of the lattice structure 10 are attached. This is indicated by the lattice structure 10 several bridge extensions 16 on, specifically two bridge extensions 16 which is the outermost region of the lattice structure in the proximal direction 10 form. The free wire ends 24 . 24 ' are up to the bridge processes 16 guided and connected there with these in the manner described below.

In 3 is the distal end of the transport wire 40 represented, in which a coupling piece 41 located. The coupling piece 41 has the function, the grid structure 10 firmly with the transport wire 40 connect so that the grid structure 10 discharged from the catheter for treatment and retrieved after thrombectomy. For this purpose, the coupling piece 41 a recess 42 on, which is transverse to the longitudinal axis of the transport wire 40 extends.

As in the mounting intermediate step according to 4 to see, the bridge extension points 16 the lattice structure 10 an engagement element 16 on, the exact fit in the recess 42 intervenes. As a result, a positive connection is created, which is strong enough to transmit the forces occurring.

About the positive connection is a crimp sleeve 30 pushed in the 4 semi-transparent is shown to reinforce the positive connection and complete.

5 shows another mounting state of the connection, in which the free wire ends 24 . 24 ' through the crimp barrel 30 passed through. Here are the free wire ends 24 . 24 ' passed through a gap between the crimp barrel 30 and the bridge extension 16 the lattice structure 10 is trained. The bridge extension 16 can be profiled in the longitudinal direction of the transport wire so that the wire ends 24 . 24 ' in a certain position, in particular parallel to one another in the crimp barrel 30 are guided. The crimp barrel 30 holds the wire ends 24 . 24 ' in the area of the coupling piece 41 in position so that the wire ends 24 . 24 ' can be fixed with adhesive.

The free wire ends 24 . 24 ' are approximately flush with the crimp barrel 30 , but may survive minimal in the proximal direction.

In the example according to 6 is a coil 50 over the free wire ends 24 . 24 ' pushed. The coil 50 is filled with glue.

Alternative to the coil 50 can, as in 7 shown in the proximal direction over the crimp barrel 30 protruding free wire ends 24 . 24 ' only with adhesive between the crimp barrel 30 and the coupling piece 41 as well as the transport wire 40 be attached. Evident here is a flattened variation of the crimp barrel ( 30 ) for a better fit. The gluing ( 43 ) tapers in the proximal direction of the crimp barrel ( 30 ) in the direction of the transport wire ( 40 ) and concludes with this flush. At the distal end of the crimp barrel ( 30 ), at which the wire ends ( 24 . 24 ' ), adhesive exits. It can be seen that even within the crimp barrel ( 30 ) the wire ends ( 24 . 24 ' ) are glued.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102014115533 A1 [0001, 0003]
• WO 2012/106657 A2 [0002]
• DE 102014115533 B1 [0016]

Claims (18)

Medical device for intravascular treatment with an at least partially tubular lattice structure (10) of integrally connected webs (11) delimiting cells (12), wherein four webs (11) by a web connector (13) are interconnected, wherein at least one X-ray visible Wire element (20, 20 ') is provided which is guided along at least one web (11) and in one end portion (10b) of the lattice structure (10) has a loop (21, 21') with a first leg (22a, 22a ') and a second leg (22b, 22b '), characterized in that the first leg (22a, 22a') and the second leg (22b, 22b ') are arranged radially inside the grid structure (10) or the first leg (22a, 22a ') and the second leg (22b, 22b') are arranged radially outside the grid structure (10). Medical device after Claim 1 characterized in that the end portion (10b) is a distal end portion (10b). Medical device after Claim 1 and 2 characterized in that the loop (21, 21 ') in an expanded state of the lattice structure (10) between two circumferentially adjacent distal end cells (12a, 12b) of the lattice structure (10) or within a distal end cell (12a, 12b) of Grid structure (10) is arranged. A medical device according to any one of the preceding claims, characterized in that the first leg (22a, 22a ') and the second leg (22b, 22b') are each passed through one of the end cells (12a, 12b). Medical device according to one of the preceding claims, characterized in that the loop (21, 21 ') in an expanded state of the lattice structure (10) of a distal web connector (13b) of the grid structure (10) in the distal direction, in particular by at least one web width , preferably at least 25% of a web length, more preferably at least 50% of a web length, is arranged at a distance. Medical device according to one of the preceding claims, characterized in that the loop (21, 21 ') divides the wire element (20, 20') into a first section (23a, 23a ') and a second section (23b, 23b'), wherein the first portion (23a, 23a ') and / or the second portion (23b, 23b') winds around a plurality of webs (11), each forming a web row (14) aligned with each other, the web row (14) helically around a longitudinal axis of the grid structure (10) extends. Medical device after Claim 6 , characterized in that the wire element (20, 20 ') in such a way around a web row (14) is wound, that the wire element (20, 20') a full turn, in particular a turn through 360 °, along the web row (14) a web (11), in particular after two webs (11), in particular after three webs (11), achieved. Medical device according to one of the preceding claims, characterized in that the wire element (20, 20 ') is formed by a completely radiopaque wire or a composite wire with a radiopaque core. Medical device according to one of the preceding claims, characterized in that two, three or four wire elements (20, 20 ') are provided, each of which forms a loop (21, 21') in the distal end section (10b) of the lattice structure (10). Medical device after Claim 9 , characterized in that the sections (23a, 23a ', 23b, 23b') of the wire elements (20, 20 ') intersect regularly along the grid structure (10), wherein between two crossing points (25) at least two, in particular at least three , and at most eight, in particular at most six, webs (11) of a web row (14) are arranged. Medical device according to one of the preceding claims, characterized in that at most four loops (21, 21 ') each with a first leg (22a, 22a') and a second leg (22b, 22b ') in a distal end portion (10b) of Grid structure (10) is arranged, wherein the first leg (22a ') and the second leg (22b') radially inside or the first leg (22a ') and the second leg (22b') are arranged radially outside of the grid structure (10) , Medical device according to one of the preceding claims, characterized in that the grid structure at a proximal end portion (10a) has at least one web extension (16) which is positively connected to a distal coupling piece (41) of a transport wire (40). Medical device after Claim 12 , characterized in that the web extension (16) has an engagement element (16a) which fits precisely into a recess (42) of the coupling piece (41), which extends transversely to a longitudinal axis of the transport wire (40). Medical device after Claim 12 or 13 , characterized in that a Crimping sleeve (30) is provided, which surrounds the web extension (16) and the coupling piece (41). Medical device after Claim 14 , characterized in that the wire element (20, 20 ') is passed through the crimping sleeve (30), wherein the wire end (24, 24') terminates approximately flush with the crimping sleeve and / or projects slightly proximally over the crimping sleeve (30) , Medical device after Claim 15 characterized in that the protruding wire end (24, 24 ') is connected to the transport wire (40) by an adhesive-filled coil (50), the coil (50) being the projecting wire end (20, 20') and the transport wire (40) encloses. Medical device after Claim 14 or 15 , Characterized in that the crimp sleeve (30.) and the projecting end of the wire (24, 24 ') with the transport wire (40) is affixed directly. A method for producing a medical device according to Claim 1 , wherein at least one wire element (20, 20 '), in particular a loop (21, 21') of the wire element (20, 20 ') is heat-treated, so that the wire element (20, 20'), in particular the loop (21, 21 ') in the expanded state, in particular in the partially expanded state, is largely stress-free.

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