Medical implant

Abstract

The invention relates to a medical implant for treating a local lesion (100) in a bifurcation of a vessel, in particular for treating a bifurcation aneurysm, with a support body (10) that is compressible and expandable, wherein the support body (10) comprises a proximal section (11) and a distal section (12) which are connected to each other, wherein - the distal section (12) is tubular, in particular cylindrical, for anchoring in the vessel, and - the proximal section (11) is conically shaped and has an opening angle (α) with respect to a longitudinal axis (L) of the supporting body (10), such that the proximal section (11) can be positioned in the vessel in such a way that the lesion (100) can be at least partially covered, and - the proximal section (11) has a first and a second porosity (13, 14), wherein the first porosity (13) is larger than the second porosity (14), so that the vessel and / or the lesion (100) in the implanted state is accessible through the first porosity (13) with a delivery device, in particular a microcatheter, and the blood flow through the second porosity (14) can be at least partially deflected from the lesion (100).

Description

[0001] The invention relates to a medical implant for treating a local lesion in a bifurcation of a vessel, in particular for treating a bifurcation aneurysm, comprising a compressible and expandable support body, wherein the support body comprises a proximal portion and a distal portion that are connected to one another. A medical implant according to the preamble of claim 1 is known, for example, from DE 102015122679 A1.

[0002] To treat vascular lesions such as aneurysms, medical implants such as flow diverters are used. These reduce blood flow into the aneurysm, allowing the blood within it to coagulate, possibly assisted by an embolic agent. The position of the flow diverter can limit interventional access to the vessels.

[0003] The invention is therefore based on the object of providing a medical implant for treating a lesion in a bifurcation of a vessel, which on the one hand enables the treatment of a lesion and on the other hand enables accessibility to the vessel, in particular to branching vessel arms.

[0004] According to the invention, this object is achieved by a medical implant having the features of claim 1.

[0005] Specifically, this problem is solved by a medical implant for treating a local lesion in a bifurcation of a vessel, in particular for treating a bifurcation aneurysm, with a compressible and expandable support body, wherein the support body comprises a proximal section and a distal section that are connected to one another. The distal section is tubular, in particular cylindrical, for anchoring in the vessel. The proximal section is conical and has an opening angle relative to a longitudinal axis of the support body, such that the proximal section can be positioned in the vessel such that the lesion can be at least partially covered.The proximal portion has a first and a second porosity, wherein the first porosity is greater than the second porosity, so that the vessel and / or the lesion in the implanted state is accessible through the first porosity with a delivery device, in particular a microcatheter, and the blood flow through the second porosity can be at least partially deflected from the lesion.

[0006] The invention has various advantages. Since the proximal section of the support body is conical and has an opening angle relative to a longitudinal axis of the support body, the proximal section can be positioned in the vessel such that a lesion in a bifurcation of a vessel can be at least partially covered. The conical shape ensures that the proximal section of the support body can adhere to the vessel wall in the area of ​​the lesion. The area of ​​the conical shape closest to the lesion follows the vessel wall in the area of ​​the lesion, ensuring good wall apposition of the support body and thus good coverage of the lesion. It is advantageous, but not absolutely necessary, that the lesion be completely covered.

[0007] In addition, the conical shape provides a certain anchoring of the proximal section in the area of ​​the bifurcation, since the area of ​​the conical shape remote from the lesion can adhere to the vessel wall in the area of ​​the feeding vessel.

[0008] The invention enables the lesion to be shielded from the blood flow in the bifurcation, while largely maintaining accessibility to the vessels and / or the lesion. For this purpose, the proximal section of the support body has a first and a second porosity, the first porosity being greater than the second porosity. The second porosity is designed such that the blood flow can be deflected away from the lesion, allowing the blood in the lesion to coagulate. The first, larger porosity ensures accessibility to the vessel and / or the lesion in the implanted state, allowing a delivery device, in particular a microcatheter, to be passed through the proximal section. The first porosity is adapted accordingly to the delivery device.

[0009] The first and second porosities of the proximal section serve a dual function. The conical first section can both divert blood flow away from the lesion and be penetrated by the delivery device to enable interventional access to distal vascular regions.

[0010] In the context of this invention, the different porosities of the proximal section are to be understood as meaning that at least two regions with different porosities can be measured along the longitudinal axis of the support body in the proximal section. These regions can merge discretely or continuously into one another. The arrangement and size of the first and second porosities can be adjusted such that both functions—that is, accessibility to the lesion and / or vessels and diversion of blood flow away from the lesion—can be fulfilled.

[0011] Preferred embodiments of the invention are specified in the subclaims.

[0012] In a particularly preferred embodiment, the wall of the proximal section is concave so that the wall can be adapted to the curvature of the vessels in a bifurcation. In other words, the wall of the proximal section can be concave so that the curvature of the wall corresponds to the curvature of the vessels. In other words, the wall can preferably be designed so that the wall follows the curvature of the vessels. In general, in a vascular bifurcation, an angle forms between branching vessels and consequently a curvature at the transition from one branching vessel to the other. A concave wall of the proximal section therefore enables optimal adaptation to the vascular anatomy in the region of a bifurcation or a lesion.

[0013] Further preferably, the wall of the proximal section has an angle of curvature between 70° and 190°, in particular at least 90°, in particular at least 110°, in particular at least 130°, in particular at least 150°, in particular at least 170°. Furthermore, the angle of curvature can in particular be a maximum of 190°, in particular a maximum of 180°, in particular a maximum of 170°. This is to be understood as meaning that the wall is designed such that the wall is adaptable to a curvature that forms in a vascular bifurcation, ie between two branching vessels that are at an angle of between 70° and 190° to one another. Such an angular range of curvature is particularly advantageous, for example, in bifurcations of the middle cerebral artery, the basilar artery, the internal carotid artery or the anterior cerebral artery.

[0014] In a further preferred embodiment, the first porosity is arranged at the proximal end and the second porosity at the distal end of the proximal section. The position of the first porosity, which is larger than the second porosity, at the proximal end of the proximal section allows blood flow in the vessels to be maintained. In other words, the blood can flow through the first porosity, ensuring sufficient supply to downstream vessels and / or tissue areas. Furthermore, the position of the second or smaller porosity at the distal end of the proximal section allows at least partial coverage of the lesion. This allows the blood flow to be diverted away from the lesion. The blood flow in the lesion is consequently reduced, allowing the blood in the lesion to coagulate.

[0015] Further preferably, the porosity changes continuously in the axial direction of the proximal section. In other words, the transition from the first to the second porosity can be continuous. Furthermore, the porosity can change continuously within the first and second porosity. Particularly preferably, the porosity of the proximal section decreases in the distal direction. This means that the greatest porosity is preferably present at the proximal end, while the distal end has the lowest porosity of the proximal section. In this way, coverage of the lesion can be achieved without restricting blood flow in branching vessels of the bifurcation. Furthermore, it is advantageous that the blood flow in the feeding vessel of the bifurcation is not or hardly impaired.

[0016] Furthermore, the distal section advantageously has a different porosity than the proximal section. Particularly preferably, the distal section has a lower porosity than the proximal section. This is advantageous because the distal section ensures good anchoring in the vessel, particularly in a vessel branching off from a bifurcation. The distal section is preferably designed such that the support body rests against the vessel wall, thus ensuring good wall adaptation.

[0017] Preferably, the proximal section has a larger cross-sectional diameter than the distal section. This makes it possible to achieve optimal coverage of a lesion in a vessel bifurcation. The larger cross-sectional diameter of the proximal section allows for good adaptation of the support body to the anatomy in the bifurcation region. This ensures secure anchoring of the support body close to the lesion.

[0018] In a further preferred embodiment, the proximal section comprises a proximal longitudinal end and the distal section comprises a distal longitudinal end of the support body, wherein the cross-sectional diameter of the proximal longitudinal end is at least 1.5 times, in particular 2 times, in particular 2.5 times, in particular 3 times larger than the cross-sectional diameter of the distal longitudinal end. It is advantageous here that the size or cross-sectional diameter of the proximal section can be selected such that the implant can be adapted to different anatomies in the region of a bifurcation.

[0019] Further preferably, the proximal section has an opening angle of at least 45°, in particular 50°, in particular 55°, in particular 60°, in particular 65°, in particular 70°, in particular 75°. The opening angle forms between the longitudinal axis and the wall of the proximal section. In other words, the conical shape of the proximal section can be described by the opening angle. Particularly preferably, the opening angle is 45°, 50°, 55°, 60°, 65°, 70°, 75°, or 80°. Alternatively, it is possible for the proximal section to have a different opening angle. The conicity of the proximal section can therefore advantageously be adapted to different anatomies.

[0020] Furthermore, the proximal section preferably has a length of at least 4 mm, in particular 5 mm, in particular 6 mm, in particular 7 mm, in particular 8 mm, in particular 9 mm, in particular 10 mm, in particular 12 mm in the axial direction. The length of the proximal section describes the distance between the proximal and distal ends of the proximal section that forms along the longitudinal axis of the support body. The length of the proximal section is particularly preferably 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm or 12 mm. Alternatively, it is possible for the proximal section to have a different length. This allows the length of the proximal section to be adapted to different anatomies in the region of a bifurcation.

[0021] The following table shows exemplary preferred parameter ranges for the length, cross-sectional diameter and opening angle of the proximal section: Length of the proximal section Cross-sectional diameter of the proximal longitudinal end Opening angle α of the proximal longitudinal end 4 mm to 6 mm 5 mm to 10 mm 50° to 60° 5 mm to 8 mm 6 mm to 13 mm 55° to 65° 8 mm to 10 mm 7 mm to 15 mm 60° to 70° 10 mm to 12 mm 8 mm to 18 mm 65° to 80°

[0022] In general, statements regarding the geometry of the implant, such as the cross-sectional diameter and / or the opening angle, refer to the implant in the expanded resting state, i.e. in the unloaded state.

[0023] The support body advantageously has a braided structure of wires, each wound around a longitudinal axis of the braided structure and crossing over and under each other, wherein the braided structure comprises between 24 and 64, in particular 48, wires. In other words, the support body can be manufactured by braiding wires. The support body can thus be formed from wires or consist of wires. The number of wires can be adapted to the application. For example, the radial force and thus the supporting effect of the implant can be influenced by the number of wires.

[0024] Furthermore, it is possible to manufacture the implant by braiding wires onto a braiding mandrel. The braiding mandrel can be customized for each patient. Various diagnostic imaging techniques, such as MRI or CT scans, can be used to visualize the vessel or lesion to be treated. Based on these images, it is possible to manufacture a braiding mandrel that is customized to the patient's anatomy. The patient-customized braiding mandrel is then used as the core on which the wires are wound helically.

[0025] Particularly preferably, the wires have a braiding angle relative to the longitudinal axis of the support body, wherein the wires in the proximal section have a different braiding angle than the wires in the distal section. In other words, the braiding angle is determined by the inclination of the wires relative to the longitudinal axis L. The advantage here is that the porosity of the support body can be easily adjusted by the braiding angle. Particularly preferably, the wires in the proximal section have a smaller braiding angle than the wires in the distal section. Consequently, the distal section preferably has less porosity than the proximal section. This allows a good supporting effect to be achieved in the distal section.

[0026] If the support body is formed from wires, as in a preferred embodiment of the invention, the porosity describes the ratio of the projected wire surface (minus the crossover area) to the total surface area of ​​the support body. In particular, the porosity in the proximal and / or distal section of the support body can be influenced by the number of wires, the wire diameter, the outer diameter of the support body, and / or the braiding angle.

[0027] Preferably, the wires in the distal section have a braiding angle between 75° and 60°, especially 75°. A braiding angle of approximately 75° in the distal section is particularly preferred, as the porosity can be adjusted to ensure a good support effect and thus good anchoring in the vessel.

[0028] In a further preferred embodiment, the wires form closed loops at the proximal longitudinal end of the braided structure. The advantage here is that the loops provide increased erection force at the proximal longitudinal end of the braided structure, thereby ensuring secure anchoring of the support body near the lesion. Furthermore, the closed loops can preferably form an enlarged diameter of the proximal longitudinal end of the support body. Such a radial expansion of the proximal longitudinal end can, for example, reduce the risk of stent migration.

[0029] It is further preferred that the wires are formed from an X-ray-visible core material, in particular platinum or a platinum alloy, and a shape memory material, in particular a nickel-titanium alloy, wherein the core material has a surface area proportion of between 10% and 50%, in particular between 20% and 30%, of the cross-sectional area of ​​the wire. The proportion of the core material in the cross-sectional area of ​​the wire depends, for example, on the wire diameter or can be adapted to the wire diameter.

[0030] It is advantageous that the wires have optimal radiopacity due to the core material. For example, the position of the implant can be easily determined by a surgeon during insertion of the implant or in the implanted state. The core material is particularly preferably made of platinum or a platinum alloy, as these materials have optimal radiopacity and consequently good radiopacity. Consequently, it is not necessary to use additional marker elements, such as marker sleeves, which can be applied or crimped onto the wire. However, the use of additional marker elements is not excluded. For example, it is possible to attach a marker element to the proximal section in such a way that, in the implanted state, it is positioned in the bifurcation or at the transition between branching vessels.This ensures correct placement of the implant, especially the proximal section, through optimal radiopacity.

[0031] Furthermore, the radiopaque core material can be coated with a shape-memory material. In other words, the surface of the wires is formed from a shape-memory material. The advantage here is that the implant is self-expanding or has self-expanding properties due to the shape-memory material.

[0032] Such wires, which are formed from an X-ray visible core material encased in a shape memory material, are generally known as DFT wires.

[0033] The wires preferably have a diameter between 20 µm and 50 µm, especially 30 µm. These wire diameters advantageously influence the radial force of the support body, thereby achieving optimal expansion and compression behavior. Furthermore, the porosity of the support body can be influenced by the wire diameter.

[0034] Further advantageously, the support body has an antithrombogenic coating, which in particular comprises heparin and / or fibrin. In other words, the support body can be coated with a material that has antithrombogenic properties. The coating can exert an anticoagulant effect, so that the adhesion of blood proteins is favorably influenced. Thus, a layer of cells, in particular endothelial cells, can form over the support body. The material of the support body is thus masked by a blood protein layer, which also prevents or reduces the deposition of platelets and coagulation proteins, for example fibrinogen, which are primarily responsible for the formation of thrombi. Overall, this results in a reduction in the tendency to form thrombi. Particularly preferably, the antithrombogenic coating comprises heparin and / or fibrin, whereby heparin can be covalently bound to fibrin.

[0035] The invention is explained in more detail using an embodiment in conjunction with the schematic drawing.

[0036] In this shows Fig. 1 shows an embodiment of a medical implant according to the invention for treating a local lesion; Fig. 2 the medical implant according to Fig. 1 in the implanted state in the area of ​​a bifurcation of a vessel.

[0037] In the following, the same reference numbers are used for identical or equivalent parts.

[0038] Fig.Figure 1 shows an embodiment of a medical implant according to the invention for treating a local lesion 100 in a vascular bifurcation. This involves the use of the implant for treating a bifurcation aneurysm. Other applications are conceivable. For example, the implant is generally suitable for treating vascular lesions 100 located in the region of a vascular branching.

[0039] The Fig. The embodiment shown in Figure 1 shows the implant in the expanded resting state, i.e. in the unloaded state of the support body 10. This means that no external forces act on the implant and it is not in use.

[0040] In Fig. 2 shows the implanted state. It can be seen that the implant is positioned in a bifurcation of a vessel to cover a vascular lesion 100. In the specific example according to Fig.2, the lesion 100 or the neck of the lesion 100 is completely covered by the support body 10 of the implant. Alternatively, it is possible for the implant to only partially cover the lesion 100.

[0041] Fig. Figure 2 further shows that a single implant is positioned in a bifurcation of a vessel. Alternatively, it is possible, for example, to position two implants according to the invention in one bifurcation.

[0042] It is in Fig. 1 that the implant comprises a support body 10 with a proximal and a distal section 11, 12 that are connected to each other. In other words, the proximal section 11 transitions into the distal section 12. In the transition region, the proximal and distal sections 11, 12 have the same cross-sectional diameter.

[0043] Furthermore, Fig.1 shows that the distal section 12 is essentially cylindrical. In other words, the distal section 12 has a substantially constant cross-sectional diameter. A different geometry of the distal section 12 is conceivable. For example, the distal section 12 can have a concave wall to improve adaptation to the vascular anatomy.

[0044] Furthermore, Fig.1, that the proximal section 11 is conical. In other words, the proximal section 11 is conically widened. The proximal section 11 has a geometry that tapers in the distal direction. It can also be seen that the proximal section 11 has an opening angle α with respect to the longitudinal axis L. This means that the conical shape of the proximal section 11 can be described or defined by the opening angle α. Due to the conical shape, the proximal section 11, as shown in Fig. 2, positioned in a vascular bifurcation such that a lesion 100 is covered to reduce blood flow into the lesion 100. The lesion 100 can be completely or partially covered by the implant.

[0045] Out of Fig.1 further shows that the proximal section 11 has a first and a second porosity 13, 14, with the first porosity 13 being greater than the second porosity 14. It can be seen that at the proximal section 11, along the longitudinal axis L, there are regions that have different porosities. This is to be understood as meaning that at least two porosities that differ from one another are measurable at the proximal section 11.

[0046] Fig. Figure 2 further illustrates that the vessels and / or the lesion 100 are accessible through the first porosity 13 with a delivery device. For example, the first porosity 13 enables interventional access to the vessels of the bifurcation and the lesion 100 itself with the aid of a microcatheter. Furthermore, Fig.2 that the blood flow through the second porosity 14 is deflected away from the lesion 100 in such a way that the blood flow into the lesion 100 is reduced, allowing the blood in the lesion 100 to coagulate. Consequently, the first and second porosities are adjusted or selected such that both functions, i.e., accessibility to the lesion and / or vessels and deflection of blood flow away from the lesion, are fulfilled.

[0047] Furthermore, Fig. 1, the wall of the proximal section is concave to adapt to the curvature of the vessels in a bifurcation. It can be seen that the wall has a curvature or is curved. Fig. Figure 2 further illustrates that a concave wall of the proximal section allows for optimal adaptation to the anatomy.

[0048] In the embodiment according to Fig.1, the wall of the proximal section has a curvature angle between 90° and 170°. Other angle ranges are conceivable. Specifically, the curvature of the wall can be adapted to the specific application or the anatomy of a bifurcation.

[0049] In Fig. 1 shows that the implant, or rather the proximal and distal sections 11, 12 of the support body 10, are rotationally symmetrical. It is conceivable that the implant may have a different geometry. Thus, the implant, or rather the proximal and / or distal section, may have a curved geometry. This is to be understood as meaning that the longitudinal axis L of the implant has a curvature, with the proximal and distal sections 11, 12 being aligned along this curvature.

[0050] In Fig.1 shows that the first porosity 13 is located at the proximal end and the second porosity 14 is located at the distal end of the proximal section 11. Consequently, the proximal section 11 has a lower porosity in its distal region than in its proximal region. It can also be seen that the first porosity 13 transitions into the second porosity 14, and vice versa.

[0051] In the embodiment according to Fig. 1, the porosity changes continuously in the axial direction of the proximal section 11. It can be seen that the proximal section 11 has the greatest porosity at its proximal end, with the porosity continuously decreasing from proximal to distal. It is also possible that the proximal section 11 has local areas with large or small porosity that are spaced apart from one another or do not merge continuously into one another.

[0052] Furthermore, Fig.1 shows that the distal section 12 has a lower porosity than the proximal section 11. Thus, it can be seen that the distal section 12 of the support body 10 has a denser structure than the proximal section 11. It is also conceivable that the distal and proximal sections 11, 12 have the same porosity. This means that the porosity of the distal section 12 can correspond to the first or second porosity 13, 14 of the proximal section 11. Furthermore, the porosity of the distal section 12 can be greater than the porosity of the proximal section 11.

[0053] It is in Fig.1 that the proximal section 11 has a larger cross-sectional diameter than the distal section 12. In other words, the proximal section 11 has a larger cross-sectional area than the distal section 12. Due to its conical shape, the proximal section 11 has a larger cross-sectional diameter than the distal section 12 at every position along the longitudinal axis L. It can be seen that the cross-sectional diameter increases in the proximal direction of the proximal section 11.

[0054] Fig.1 shows that the proximal section 11 comprises a proximal longitudinal end 15 and the distal section 12 comprises a distal longitudinal end 16 of the support body 10. In the illustrated embodiment, the cross-sectional diameter of the proximal longitudinal end 15 is at least 1.5 times larger than the cross-sectional diameter of the distal longitudinal end 16. Other size ratios between the proximal and distal longitudinal ends 15, 16 are conceivable. For example, the proximal longitudinal end 15 can be 2 times, 2.5 times, or 3 times larger than the cross-sectional diameter of the distal longitudinal end 16.

[0055] In Fig.1 further shows that the proximal section 11 has an opening angle α of at least 45°. It can be seen that the opening angle α is formed between the longitudinal axis L and the wall of the proximal section 11. It is also conceivable for the proximal section 11 to have a different, in particular larger, opening angle α. For example, the opening angle α can be 50°, 55°, 60°, 65°, 70°, 75°, or 80°.

[0056] Furthermore, the proximal section 11 in the embodiment according to Fig.1 has a length of at least 4 mm in the axial direction. The length of the proximal section 11 is understood to mean the length between the proximal and distal longitudinal ends 15, 16 of the proximal section 11, measured along the longitudinal axis L. For example, the length of the proximal section 11 can be 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, or 12 mm. Other lengths of the proximal section 11 are conceivable.

[0057] Out of Fig.1 further shows that the support body 10 has a braided structure of wires 17, each wound around a longitudinal axis L of the braided structure and crossing over and under each other. In the specific exemplary embodiment, the braided structure is formed from 48 wires 17. A different number of wires 17 is conceivable. Thus, the braided structure can comprise between 24 and 64 wires 17. The braided structure is produced by braiding the wires 17, with the wires 17 forming meshes of the braided structure.

[0058] The braided structure can be produced using different braiding techniques. For example, a process known as plying can be used to produce the braided pattern. Plying means that at least two filaments are placed next to one another in the same plane. Thus, the implant can have a wall that is braided at least in some regions and comprises strands formed from a plurality of filaments that are interwoven with one another and / or with individual filaments, wherein at least one strand consists of a plurality of filaments that are all arranged next to one another in the same plane extending along the wall, and the filaments of one strand have different diameters, or the diameters of the filaments vary between a plurality of strands and are the same within one strand. The plying, i.e.The formation of flat strands with different numbers of filaments makes it possible, for example, to achieve high radial forces at the ends of the implant.

[0059] The wire(s) can be braided in a 1-over-1 or 1-over-2 arrangement. Other arrangements are possible.

[0060] Furthermore, the implant can be manufactured by twisting wires. In braiding terms, twisting refers to the intertwining of two or more wires that wrap around each other at a 360-degree angle.

[0061] It is also in Fig.1 that the wires 17 have a braiding angle relative to the longitudinal axis L of the support body 10. It can be seen that the braiding angle is enclosed by the longitudinal axis L and a wire section of the wire 17 that intersects the longitudinal axis L. The wires 17 in the proximal section 11 have a smaller braiding angle than the wires 17 in the distal section 12. It is also possible for the wires 17 in the proximal and distal sections 11, 12 to have the same braiding angle. Alternatively, the braiding angle of the wires 17 in the proximal section 11 can be greater than in the distal section 12.

[0062] In the concrete example according to Fig. 1, the wires 17 in the distal section 12 have a braiding angle of 75°. A different braiding angle is conceivable. For example, the braiding angle in the distal section 12 can be between 60° and 75°.

[0063] Furthermore, Fig.1, that the wires 17 form closed loops 18 at the proximal longitudinal end 15 of the braided structure. The wires 17 are deflected at the proximal longitudinal end 15 in such a way that end loops 18 are formed. In other words, the wires 17 forming the braided structure are wound helically around the longitudinal axis L, deflected at the proximal longitudinal end 15 and again wound helically in the opposite direction around the longitudinal axis L. This creates open wire ends at the distal longitudinal end 16. Specifically, for example, 24 loops 18 are formed at the proximal longitudinal end 15 if 24 wires 17 are used. Since the 24 wires 17 are deflected to form the end loops 18, 48 wire ends can be seen at the distal longitudinal end 16 of the braided structure. The end loops 18 are arranged next to each other in the circumferential direction of the gel fencing structure.

[0064] It is also possible for the end loops 18 to be configured as multiple loops or double loops. At least two loops 18 are arranged one behind the other in the longitudinal direction of the braided structure. If a multiple loop is configured as a double loop, the end loop comprises an inner and an outer loop. Thus, a first wire can form a first loop and a second wire a second loop, with the first loop and the second loop being arranged at a distance from each other. Multiple loops can further improve the anchoring of the implant in a bifurcation of a vessel.

[0065] The wires 17 in the embodiment according to Fig.1 are formed from an X-ray-visible core material, such as platinum or a platinum alloy, and a shape memory material, such as a nickel-titanium alloy. Specifically, the core material has an area share of between 20% and 30% of the cross-sectional area of ​​the wire 17. A different area share is conceivable. For example, the core material can have an area share of between 10% and 50% of the cross-sectional area of ​​the wire 17. It is conceivable that the wires are formed from a different material. For example, the wires can be formed from a cobalt-chromium alloy or a comparable material.

[0066] Furthermore, the wires 17 have a wire diameter of 30 µm. Other wire diameters are possible. For example, the wire diameter can be between 20 µm and 50 µm.

[0067] In the embodiment according to Fig.1, the support body 10 has an antithrombogenic coating. Specifically, the support body 10 is coated with a coating of heparin and fibrin, with heparin covalently bonded to fibrin. Other coatings that impart antithrombogenic properties to the support body 10 are conceivable. For example, the coating may comprise fibronectin.

[0068] All embodiments and examples can be delivered or positioned in the vessel using a suitable delivery system, such as a catheter. Different catheter systems can be used for different implant sizes or cross-sectional diameters. List of reference symbols 10 support bodies 11 proximal section 12 distal section 13 first porosity 14 second porosity 15 proximal longitudinal end 16 distal longitudinal end 17 wire 18 loops 100 lesion α opening angle L Longitudinal axis 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] DE 102015122679 A1

[0001]

Claims

[1] Medical implant for treating a local lesion (100) in a bifurcation of a vessel, in particular for treating a bifurcation aneurysm, with a support body (10) which is compressible and expandable, wherein the support body (10) comprises a proximal section (11) and a distal section (12) which are connected to one another, characterized by , that - the distal section (12) is tubular, in particular cylindrical, for anchoring in the vessel, and - the proximal section (11) is conical and has an opening angle (α) relative to a longitudinal axis (L) of the support body (10), so that the proximal section (11) can be positioned in the vessel such that the lesion (100) can be at least partially covered, and - the proximal section (11) has a first and a second porosity (13, 14), wherein the first porosity (13) is greater than the second porosity (14), so that the vessel and / or the lesion (100) in the implanted state is accessible through the first porosity (13) with a delivery device, in particular a microcatheter, and the blood flow through the second porosity (14) can be at least partially deflected from the lesion (100). [2] Medical implant according to claim 1, characterized by that the wall of the proximal section (11) is concave so that the wall can be adapted to the curvature of the vessels in a bifurcation. [3] Medical implant according to claim 1 or 2 characterized by that the wall of the proximal section (11) has an angle of curvature between 70° and 190°, in particular at least 90°, in particular at least 110°, in particular at least 130°, in particular at least 150°, in particular at least 170°. [4] Medical implant according to one of the preceding claims characterized by that the first porosity (13) is arranged at the proximal end and the second porosity (14) at the distal end of the proximal section (11). [5] Medical implant according to one of the preceding claims characterized by that the porosity changes continuously in the axial direction of the proximal section (11). [6] Medical implant according to one of the preceding claims characterized by that the distal section (12) has a different, in particular lower, porosity than the proximal section (11). [7] Medical implant according to one of the preceding claims characterized by that the proximal section (11) has a larger cross-sectional diameter than the distal section (12). [8] Medical implant according to one of the preceding claims characterized byin that the proximal section (11) comprises a proximal longitudinal end (15) and the distal section (12) comprises a distal longitudinal end (16) of the support body (10), wherein the cross-sectional diameter of the proximal longitudinal end (15) is at least 1.5 times, in particular 2 times, in particular 2.5 times, in particular 3 times larger than the cross-sectional diameter of the distal longitudinal end (16). [9] Medical implant according to one of the preceding claims characterized by that the proximal section (11) has an opening angle (α) of at least 45°, in particular 50°, in particular 55°, in particular 60°, in particular 65°, in particular 70°, in particular 75°, in particular 80°. [10] Medical implant according to one of the preceding claims characterized bythat the proximal section (11) has a length of at least 4 mm, in particular 5 mm, in particular 6 mm, in particular 7 mm, in particular 8 mm, in particular 9 mm, in particular 10 mm, in particular 11 mm, in particular 12 mm in the axial direction. [11] Medical implant according to one of the preceding claims characterized by in that the support body (10) has a braided structure of wires (17), which are each wound around a longitudinal axis of the braided structure and cross over and under each other, wherein the braided structure comprises between 24 and 64, in particular 48, wires (17). [12] Medical implant according to one of the preceding claims characterized by that the wires (17) have a braiding angle relative to the longitudinal axis (L) of the support body (10), wherein the wires (17) in the proximal section (11) have a different, in particular smaller, braiding angle than the wires (17) in the distal section (12). [13] Medical implant according to one of the preceding claims characterized by that the wires (17) in the distal section (12) have a braiding angle between 75° and 60°, in particular 75°. [14] Medical implant according to one of the preceding claims characterized by that the wires (17) form closed loops (18) at the proximal longitudinal end (15) of the braid structure. [15] Medical implant according to one of the preceding claims characterized by that the wires (17) are formed from an X-ray visible core material, in particular platinum or a platinum alloy, and a shape memory material, in particular a nickel-titanium alloy, wherein the core material has an area proportion of between 10% and 50%, in particular between 20% and 30%, of the cross-sectional area of ​​the wire (17). [16] Medical implant according to one of the preceding claims characterized bythat the wires (17) have a wire diameter between 20 µm and 50 µm, in particular 30 µm. [17] Medical implant according to one of the preceding claims characterized by that the support body (10) has an antithrombogenic coating, which in particular comprises heparin and / or fibrin.

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