Arrangement for delivering a medical implant; wire for delivering; catheter with an arrangement

Abstract

The invention relates to an arrangement for delivering a medical implant into a hollow body organ (100) comprising a wire (10) and a compressible and expandable medical implant (11) which is tubular in shape, wherein the implant (11) in the compressed state is detachably connected to the wire (10) by at least one engagement element (12), wherein the engagement element (12) has a plurality of filaments (13) which extend outwards in the radial direction of the wire (10) and engage in the implant (11) during use.

Description

[0001] The invention relates to an arrangement for delivering a medical implant into a hollow body organ, comprising a wire and a compressible and expandable medical implant that is tubular in shape. The implant, in the compressed state, is releasably connected to the wire by at least one engagement element. The invention further relates to a wire for delivering a medical implant into a hollow body organ and a catheter.

[0002] The arrangement mentioned above is known, for example, from WO 2013 / 107783 A1, which originates from the applicant. A wire having the features of the preamble of claim 10 is also known from this prior art.

[0003] This arrangement, or rather, this wire, has proven extremely effective in practice and enables the safe delivery of an implant, such as a stent or flow diverter, to the treatment site through a catheter. Upon release from the catheter, the implant is detached from the wire and remains at the treatment site. The wire is retracted through the catheter.

[0004] The implant is deployed by a relative axial movement between the catheter and the implant at the treatment site. The implant emerging from the catheter unfolds or expands, with the expansion movement progressively progressing proximal to the implant as the deployment progresses. As the implant expands in the area of the engagement element, the radial outward movement releases the implant from the wire, and the implant and engagement element are separated. The implant is fully deployed and expanded at the desired location in the vessel to be treated.

[0005] If the radial outward movement of the implant is restricted, for example, by patient-specific vascular properties in the area of the treatment site, so that the radial distance between the implant and the interventional element is small, the release of the implant can be made more difficult.

[0006] The invention is therefore based on the object of providing an arrangement by which the implant can be released as safely as possible, even under difficult conditions. The invention is further based on the object of providing a corresponding wire and a catheter.

[0007] According to the invention, the object is achieved with regard to the arrangement by the subject matter of claim 1, with regard to the wire by the subject matter of claim 10 and with regard to the catheter by the subject matter of claim 11.

[0008] Specifically, the problem is solved by an arrangement for delivering a medical implant into a hollow body organ, comprising a wire and a compressible and expandable medical implant that is tubular in shape. The implant, in the compressed state, is releasably connected to the wire by at least one engagement element. The engagement element has a plurality of filaments that extend outward in the radial direction of the wire and engage the implant during use.

[0009] The invention has the advantage that the implant is securely connected to the wire by the filaments of the engagement element during implant insertion. To this end, the filaments of the engagement element engage the implant during use in such a way that the implant can be moved together with the wire. This allows the implant to be safely transported to the treatment site. The engagement of the implant in the filaments also ensures that the implant can be moved with the wire in both longitudinal directions of the wire. The filaments thus fulfill a holding function.

[0010] The engaging element, which comprises the filaments, is firmly connected to the wire during use. For example, the engaging element can be firmly bonded to the wire. Other connections are possible. The filaments are therefore also fixed to the wire and move the implant along with it when the wire is moved. This allows the implant to be safely transported to the treatment site by advancing the wire.

[0011] During use, the filaments advantageously engage the implant in such a way that the implant is connected to the wire in a force-locking manner. The plurality of filaments allows a force-locking connection between the implant and the engaging element to be achieved. When the wire is advanced, the filaments transfer a force to the implant, causing the implant to move along with the wire.

[0012] Alternatively, the filaments engage the implant during use, creating a positive connection to the wire. The filaments are designed to engage corresponding openings in the implant. The filaments can penetrate through the implant, ensuring a positive connection.

[0013] Furthermore, the filaments can engage the implant during use in such a way that the implant is connected to the wire in a force-fitting and form-fitting manner. The combination of both connection types—i.e., a force-fitting and form-fitting connection between the implant and the engagement element—creates a particularly good connection between the implant and the wire, ensuring safe delivery and correct positioning of the implant at the treatment site. The retention function of the filaments can thus be achieved through various connection types.

[0014] During use, the filaments of the engagement element engage at least a portion of the implant. For example, the filaments can engage the proximal and / or distal end of the implant. Alternatively, it is conceivable for the filaments to engage the entire length of the implant. The length of engagement of the filaments in the implant can be adapted to the specific application or the type of implant.

[0015] The filaments extend radially outward from the wire and form free ends. The free ends or end sections of the filaments form an outer contour that is adapted to the contour, in particular the inner contour, of the implant. The outer contour of the filaments is preferably adapted to the contour, in particular the inner contour, of the tubular implant.

[0016] The invention is suitable for self-expanding medical implants. The medical implant of the arrangement can therefore be self-expanding. Once the implant has reached the treatment site and the outer catheter, which holds the implant in a compressed state, is withdrawn, the implant preferably expands automatically. The implant then leaves the engagement with the filaments of the engagement element, leaving the implant free. The wire can then be removed from the hollow body organ, leaving the implant in the hollow body organ.

[0017] If the distance between the engagement element and the implant is relatively small, it is possible that the filaments or their free ends will at least partially engage the implant. Since the force transmitted to the implant by the end sections of the filaments is relatively low, the wire can be easily retracted even if the filaments are partially engaged with the implant. The filaments of the engagement element therefore fulfill a protective function. This protective function is to prevent the engagement element from becoming caught in an already implanted implant. This results in a particularly low risk of the already implanted implant being set in motion again and its correct positioning at the treatment site being changed.

[0018] The filaments can be designed to be flexible. The filaments advantageously exhibit greater flexibility as their distance from the wire increases. If individual filaments or their free ends engage the implant during retraction of the wire, the filaments can bend in such a way that the implant cannot become entangled with the engaging element, allowing the wire to be safely retracted into the catheter.

[0019] The filaments are preferably elastic. This advantageously makes them bendable. On the one hand, the filaments can be so elastic that the implant can be safely released from the filaments when the wire is advanced and / or in the event of entanglement with the implant. On the other hand, the filaments can be so rigid that they act as a driver for the implant.

[0020] For example, the filaments are formed as bristles or wires.

[0021] The implant may preferably have a lattice structure, in particular a tubular wall made of a lattice structure.

[0022] The lattice structure can be a mesh of braided wires or a single braided wire. The mesh forms meshes. The lattice structure can also be a monolithic lattice structure made up of webs, for example, a laser-cut lattice structure. The monolithic lattice structure forms cells.

[0023] The inventive arrangement comprising an implant and a wire is treated as an assembly that is disclosed and claimed independently of the catheter used to transport the arrangement to the treatment site. In addition, the combination of a catheter and the inventive arrangement is also disclosed and claimed. Within the scope of the invention, the wire for delivering the medical implant as such, i.e., without an implant and without a catheter, is also disclosed and claimed. The wire is suitable for achieving the advantages explained above in connection with the delivery of an implant and, for this purpose, has an engagement element modified according to the invention, which is described above. Such a wire is also referred to as a transport wire.

[0024] Preferred embodiments of the invention are claimed or specified in the subclaims.

[0025] The engagement element can comprise a support section that is connected to the wire during use and carries the filaments. The engagement element can be formed from or consist of the support section and the filaments. For example, the support section can be integrally connected to the wire. The support section can be ring-shaped or sleeve-shaped and have a central opening through which the wire extends during use. The filaments are preferably arranged on an outer circumference of the support section. By connecting the support section to the wire, a stationary arrangement of the filaments on the wire is achieved. This allows the implant to be moved securely with the wire.

[0026] Preferably, the filaments are formed integrally with the carrier section. The engagement element, including the carrier section and the filaments, can be formed monolithically. The filaments and the carrier section can thus advantageously be manufactured in one piece. For example, the engagement element or the carrier section and the filaments can be manufactured by additive manufacturing, such as 3D printing. Other manufacturing methods are conceivable. For example, the engagement element can be manufactured by mechanical processing, such as milling or laser material processing.

[0027] Alternatively, the filaments can be embedded in the carrier section. For example, the filaments can be firmly bonded to the carrier section. For this purpose, the carrier section can have corresponding receiving areas, particularly recesses, on its outer circumference into which the filaments can be inserted and, if necessary, glued.

[0028] Preferably, the filaments are distributed in the circumferential and / or axial direction of the wire. The filaments can be distributed over the outer circumference of the support section. In particular, the filaments are distributed substantially uniformly in the circumferential direction of the wire. This allows the filaments to fully engage the implant. The holding function of the filaments or the engagement element is thus improved.

[0029] The engagement element can have between 10 and 50, in particular at least 20, in particular at least 30, in particular at least 40, filaments. The number of filaments can be adapted to the implant used. For example, the number of filaments can be adapted to the implant's meshwork, mesh size, or cell count. It has been shown that a number between 10 and 50 filaments per engagement element is suitable for a wide range of applications. For example, the number of filaments can be lower if an implant with small mesh openings is to be delivered. If an implant with large mesh openings is used, the number of filaments can be higher. Alternatively, it is possible for the engagement element to have more than 50 or fewer than 10 filaments.

[0030] In one embodiment, several engagement elements can be arranged next to one another in the axial direction of the wire, wherein the engagement elements are spaced apart from one another or adjacent to one another. Spacer elements can be arranged between the engagement elements. The spacer elements can be annular or sleeve-shaped. The spacer elements ensure that the engagement elements maintain the required distance from one another to enable good engagement of the filaments in the implant. Alternatively, the engagement elements or the support sections of the engagement elements can be adjacent to one another. The support sections can be arranged such that they touch or abut one another.

[0031] The number of engagement elements can be adjusted such that the plurality of engagement elements extend over a maximum of 30%, in particular a maximum of 20%, in particular a maximum of 10%, of the length of the implant. It has been shown that a good fit of the implant on the engagement element is already achieved when the engagement elements extend over a maximum of 30% of the length of the implant. The engagement elements extend over a partial section of the implant. For example, the filaments can engage the proximal or distal end of the implant. The filaments can engage the end meshes or end cells of the implant. This embodiment has the advantage that even implants with a cover or membrane can be fed into a body organ, since the filaments only engage those areas of the implant that are free of cover. Damage to such a membrane by the filaments can be avoided in this way.It is also possible for a single elongated engagement element to extend over a maximum of 30% of the implant's length. Furthermore, it is conceivable for the engagement element(s) to extend over the entire implant length.

[0032] The filaments are preferably made of a flexible material, particularly a polymer. This advantageously makes the filaments bendable. This is particularly advantageous when individual filaments engage the implant during retraction of the wire. This flexibility allows the filaments to bend in such a way that the implant cannot become snagged and the wire can be safely retracted into the catheter.

[0033] The end sections or the areas of the filaments remote from the wire are preferably more flexible than the areas close to the wire. The areas of the filaments close to the wire preferably have greater stiffness than the areas remote from the wire or the free ends of the filaments. With increasing distance from the wire, the filaments advantageously have greater flexibility. This is due in particular to the connection of the filaments to the carrier section. In the compressed state, the implant is preferably or at least largely engaged with the areas of the filaments close to the wire. This ensures that the implant sits securely on the engagement element or in the filaments. In the compressed state, the more flexible end sections of the filaments can bend in such a way that they penetrate the implant and adhere to the outer contour of the implant.The end sections can be arranged between the implant and the outer catheter when delivering the implant.

[0034] On the one hand, the filaments can be so flexible that the implant can be safely released from the filaments when the wire is advanced and / or if the implant becomes entangled. On the other hand, the filaments can be so rigid that they act as a driver for the implant.

[0035] The flexibility of the filaments can be adapted to the implant used. For example, the filaments are designed to be more flexible if an implant with small lattice openings is to be delivered. The filaments can be less flexible or stiffer if an implant with large lattice openings is to be used.

[0036] For example, the engagement element or the filaments of the engagement element are made of polyolefin (e.g., PP, PE), polyurethane (e.g., thermoplastic polyurethane, hydrophilic polyurethane), polyamide (e.g., PA6.6), polyester (e.g., PLA, PLGA, PET), polysulfone (e.g., PSU), and / or polyetheretherketone (PEEK). Alternatively, it is conceivable that the engagement element or the filaments of the engagement element are made of metal, for example, stainless steel or a nickel-titanium alloy. The invention is not limited to specific materials for the engagement element or the filaments. Other materials are possible.

[0037] The filaments can have a diameter between 5 µm and 50 µm, in particular no more than 10 µm, in particular no more than 20 µm, in particular no more than 30 µm, in particular no more than 40 µm. The filaments can be so fine that they can easily engage the implant or the mesh openings of an implant. The diameter of the implant can be adapted to the implant used.

[0038] The invention will be explained in more detail below using an exemplary embodiment with reference to the accompanying drawings. Fig. 1 a sectional view of an arrangement with a wire and an implant according to an embodiment of the invention; and Fig. 2 a side view of the arrangement according to Fig. 1.

[0039] Fig. Figure 1 shows an embodiment of an arrangement according to the invention for delivering a medical implant 11 into a hollow body organ, which is particularly, but not exclusively, suitable for the treatment of neurovascular diseases. The arrangement serves, for example, to treat aneurysms, fistulas, dissections, or stenoses. Other areas of application are possible.

[0040] The arrangement comprises a wire 10, which may also be referred to as a transport wire or a retention wire, and the implant 11. The arrangement of wire 10 and implant 11 forms an assembly preloaded in a catheter (not shown). Within the scope of the application, the assembly is disclosed and claimed, as is the wire 10 without the implant 11. Furthermore, the combination of catheter and arrangement or assembly, which typically forms the economic unit that is marketed, is disclosed and claimed.

[0041] The implant 11 is tubular and compressible and expandable in a conventional manner to be transported through the catheter to the lesion to be treated. The implant 11 is preferably self-expanding. This can typically be achieved by making the implant 11 from a shape-memory material, such as nitinol. The invention is not limited to specific implant materials. Other implant materials are possible.

[0042] The tubular implant 11, specifically its wall, is formed from a lattice structure. The lattice structure is formed from lattice elements that define lattice openings. The lattice structure 11 can comprise interwoven wires that form meshes. Alternatively, the lattice structure can be formed from monolithic webs that define cells. Examples of such implants 11 are stents or flow diverters. Other implants 11 are possible that can be detachably connected to the wire 10.

[0043] The wire 10 is designed in a conventional manner and comprises, for example, coils arranged on a core (not shown). Other designs of the wire 10 are possible.

[0044] The implant 11 is detachably connected to the wire 10 in the compressed state by an engagement element 12. When the implant 11 is inserted, the implant 11 is connected to the wire 10 in the compressed state via the engagement element 12. When the implant 11 has reached the treatment site and the catheter (not shown), which holds the implant 11 in the compressed state, is withdrawn, the implant 11 expands automatically (see Fig. 2). The implant 11 then leaves the engagement with the engagement element 12, thereby releasing the implant 11.

[0045] The engagement element 12 has a plurality of filaments 13 that extend outward in the radial direction of the wire 10. The filaments 13 are formed as extensions that extend in the radial direction, wherein the extensions are separated or spaced apart from one another by recesses in the circumferential direction of the engagement element 12.

[0046] In the embodiment according to Fig. 1, the filaments 13 are designed as bristles. Alternatively, the filaments 13 can be designed as wires that are flexible or bendable.

[0047] The filaments 13 are arranged similarly to or as in a round brush. The arrangement of the filaments 13 around the wire 10 is comparable to the arrangement of the bristles of a brush.

[0048] Fig. 1 shows the implant 11 in the compressed state. It can be seen that the filaments 13 engage in the implant 11 and connect the implant 11 to the wire 10. The multitude of filaments 13, which engage in the implant 11 in the compressed state, holds the implant 11 firmly on the wire 10. The filaments 13 engage in the implant 11 in such a way that the implant 11 is connected to the wire 10 in a form-fitting and / or force-fitting manner. The filaments 13 penetrate the lattice openings of the implant 11 and, when the wire 10 is advanced, transmit a force to the lattice structure of the implant 11, so that the implant 11 moves along with the wire 10. The filaments 13 enable the engagement element 12 to fulfill its holding function.

[0049] Fig. Figure 2 shows the implant 11 in its partially expanded state. It can be seen that the filaments 13 at the proximal end of the implant 11 are engaged with the implant 11. The distal end of the implant 11 is already released. If the wire 10 is advanced further, the implant 11 is completely released from the engagement of the filaments 13.

[0050] In addition to their holding function, the filaments 13 also fulfill a protective function. This protective function consists in preventing the engagement element 12 from becoming caught in an already implanted implant 11. This reduces the risk of the already implanted implant 11 changing its correct positioning at the treatment site. This protective function is achieved by the relatively low force that the end sections of the filaments 13 transmit to the implant 11. Thus, the wire 10 can be easily retracted even if the filaments 13 are partially engaged with the implant 11.

[0051] The engagement element 12 comprises a support portion 14 that supports the filaments 13. The support portion 14 is ring-shaped or sleeve-shaped and has a central opening through which the wire 10 extends. In use, the support portion 14 is firmly connected to the wire 10. For example, the support portion 14 is integrally connected to the wire 10.

[0052] In the embodiment according to Fig. 1, the filaments 13 are formed integrally with the carrier section 14. The carrier section 14 and the filaments 13 are manufactured in one piece, for example, by additive manufacturing. Alternatively, the filaments 13 can be embedded in the carrier section 14.

[0053] Fig. Figure 1 shows that the filaments 13 are evenly distributed in the circumferential direction of the support section 14. The filaments 13 are evenly distributed on the outer circumference of the support section 14. It can be seen that the filaments 13 fully engage the implant 11.

[0054] The engagement element 12 has between 10 and 50, in particular at least 20, in particular at least 30, in particular at least 40, filaments 13. In the embodiment according to Fig. 1, the engagement element 12 has 24 filaments 13 that extend outward in the radial direction of the engagement element 12. The number of filaments 13 is adapted to the implant 11.

[0055] Fig. Figure 2 shows that several engagement elements 12 are arranged next to one another in the axial direction of the wire 10. The engagement elements 12 are arranged at a distance from one another. It can be seen that six engagement elements 12 are arranged next to one another on the wire 10 and are spaced from one another. Alternatively, it is possible for the six engagement elements 12 to be adjacent to one another.

[0056] The number of engagement elements 12 is in Fig. 2 such that the engagement elements 12 extend over a maximum of 30% of the length of the implant 11. This allows the Fig. 2 may, for example, have a membrane which remains intact, ie undamaged, due to the engagement of the filaments 13 in the membrane-free end region of the implant 11.

[0057] The filaments 13 are made of a flexible material, such as plastic. This makes them bendable. The flexibility of the filaments 13 is adapted to the implant 11 used. When the wire 10 is retracted, individual filaments 13 can engage the implant 11. This flexibility causes the filaments 13 to bend in such a way that the implant 11 cannot become snagged and the wire 10 can be safely retracted into the catheter.

[0058] The filaments 13 have a diameter between 5 µm and 50 µm, in particular a maximum of 10 µm, in particular a maximum of 20 µm, in particular a maximum of 30 µm, in particular a maximum of 40 µm. The diameter is selected such that the filaments 13 can engage the meshes or cells of the implant 11. List of reference symbols 10 wire 11 Implant 12 engagement element 13 filaments 14 support section QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This 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

[0000] WO 2013 / 107783 A1

[0002]

Claims

[1] Arrangement for introducing a medical implant into a hollow body organ (100) with a wire (10) and a compressible and expandable medical implant (11) which is tubular in shape, wherein the implant (11) in the compressed state is detachably connected to the wire (10) by at least one engagement element (12), characterized by that the engagement element (12) has a plurality of filaments (13) which extend outwards in the radial direction of the wire (10) and engage in the implant (11) during use. [2] Arrangement according to claim 1, characterized by that the engagement element (12) comprises a support portion (14) which, in use, is connected to the wire (10) and carries the filaments (13). [3] Arrangement according to claim 1 or 2, characterized by that the filaments (13) are formed integrally with the carrier section (14) or are embedded in the carrier section (14). [4] Arrangement according to one of the preceding claims, characterized by that the filaments (13) are arranged, in particular substantially uniformly, distributed in the circumferential direction and / or axial direction of the wire (10). [5] Arrangement according to one of the preceding claims, characterized by that the engagement element (14) has between 10 and 50, in particular at least 20, in particular at least 30, in particular at least 40, filaments (13). [6] Arrangement according to one of the preceding claims, characterized by that a plurality of engagement elements (12) are arranged next to one another in the axial direction of the wire (10), wherein the engagement elements (12) are spaced apart from one another or adjacent to one another. [7] Arrangement according to one of the preceding claims, characterized bythat the number of engagement elements (12) is adapted such that the plurality of engagement elements (12) extend over at most 30%, in particular at most 20%, in particular at most 10%, of the length of the implant (11). [8] Arrangement according to one of the preceding claims, characterized by that the filaments (13) are formed from a flexible material, in particular from a polymer. [9] Arrangement according to one of the preceding claims, characterized by that the filaments (13) have a diameter between 5 µm and 50 µm, in particular at most 10 µm, in particular at most 20 µm, in particular at most 30 µm, in particular at most 40 µm. [10] Wire for introducing a tubular medical implant (11) into a hollow body organ (100), wherein the implant (11) is compressible and expandable and, in the compressed state, can be connected to the wire (10) by at least one engagement element (12), characterized bythat the engagement element (12) has a plurality of filaments (13) which extend outwards in the radial direction of the wire (10) and engage in the implant (11) during use. [11] Catheter with an arrangement according to claim 1.

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