Medical implant, and method for producing a medical implant

Abstract

The invention relates to a medical implant (10) for treating a local lesion in a vessel, in particular in a bifurcation of a vessel, having a compressible and expandable support body (11) made of webs (15) which delimit cells (16), wherein the support body (11) comprises at least one proximal portion (12), at least one distal portion (13) and at least one central portion (14) which is arranged between the proximal and distal portions (12, 13), wherein the proximal and distal portions (12, 13) have a membrane (17) which at least partially covers the cells (16) of the proximal and distal portions (12, 13), wherein the implant (10) comprises at least one covering element (18) which is connected to the proximal portion (12) and is loosely arranged in the region of the central portion (14), in order to at least partially release the blood flow in the radial direction through the central portion (14) in the implanted state.

Description

[0001] Acandis GmbH February 16, 2026 M / CAN-433-PC JK / AS / pk

[0002] Medical implant, method for manufacturing a medical implant

[0003] Description

[0004] The invention relates to a medical implant for treating a local lesion in a blood vessel. A medical implant according to the preamble of claim 1 is known, for example, from DE 10 2018 131 269 B4, which is attributed to the applicant.

[0005] Furthermore, the invention relates to a method for manufacturing a medical implant.

[0006] Medical implants, such as stents, are used to treat vascular lesions like stenoses. These implants are positioned at the site of the lesion and at least partially cover it. In the case of a stenosis, this coverage by the implant is particularly important to prevent plaque from breaking off and entering the bloodstream, which could, for example, lead to a stroke.

[0007] If a lesion is located in or near a bifurcation, the problem often arises that blood flow into an outgoing vessel is restricted by the position of the implant. This can lead to an insufficient supply of nutrients to the downstream tissue areas.

[0008] The invention is therefore based on the objective of providing a medical implant for the treatment of a lesion in a vessel, which on the one hand enables the treatment of the lesion and on the other hand maintains blood flow into branching vessels. Furthermore, the invention is based on the objective of providing a method for manufacturing such an implant. 102025106826.7 M / CAN-433-PC 2

[0009] According to the invention, this problem is solved by a medical implant having the features of claim 1. With regard to the method, this problem is solved by the subject matter of claim 18.

[0010] Specifically, the problem is solved by a medical implant for treating a local lesion in a vessel, particularly in a vessel bifurcation, with a compressible and expandable support structure made of ribs that delimit cells. The support structure comprises at least one proximal section, at least one distal section, and at least one middle section located between the proximal and distal sections. The proximal and distal sections have a membrane that at least partially covers the cells of the proximal and distal sections. The implant includes at least one cover element that is connected to the proximal section and is loosely arranged in the region of the middle section to at least partially allow blood flow in a radial direction through the middle section when implanted.

[0011] The invention has several advantages.

[0012] The medical implant according to the invention enables the efficient treatment of a local lesion, particularly a stenosis, without significantly affecting blood flow into a branching vessel near the lesion. For this purpose, the implant has a cover element that is connected to the proximal section of the support body and is loosely arranged in the region of the central section. The cover element is preferably rigidly connected only to the proximal section and extends distally from the proximal section. The cover element preferably spans at least the central section without having any direct connection points to it. The cover element preferably rests loosely against or on the central section. This advantageously allows the cover element to be relatively movable relative to the support body in the region of the central section.

[0013] Due to the loose arrangement of the cover element in the central section, the cover element can be positioned in a vessel or bifurcation in such a way that it extends at least partially into a branching vessel. Advantageously, the cover element opens in the implanted state in such a way as shown in 102025106826.7 M / CAN-433-PC 3

[0014] The outgoing vessel opens up in such a way that it forms a free or open area through which blood can flow radially through the central segment and consequently into the outgoing vessel. This ensures the supply of nutrients to the outgoing vessel.

[0015] Furthermore, the cover element advantageously ensures efficient coverage of a lesion located near a bifurcation. In particular, a lesion situated substantially opposite an outgoing vessel can be covered by the cover element. When the cover element is positioned in a bifurcation, it opens into the outgoing vessel on one side. On a second side opposite the first, the cover element is pressed against the support body and thus rests on it. Specifically, in the implanted state, the cover element is fixed between the vessel wall and the support body on the side opposite the outgoing vessel by the radial force of the support body. This allows a lesion situated substantially opposite an outgoing vessel to be covered and thus efficiently treated by the cover element.This reduces the risk of plaque breaking off and entering the bloodstream.

[0016] The covering element is preferably designed to adapt to the vascular anatomy, particularly in the area of ​​a bifurcation. The covering element can be flexible, allowing it to extend at least partially into an outgoing vessel and to conform to the supporting structure, especially the midsection. For example, the covering element can be a textile, a nonwoven fabric, or a film.

[0017] During the insertion of the implant into a vessel, the cover element is preferably compressed onto the support body. The cover element preferably rests fully against the support body or the central section. Upon release of the implant, the cover element can unfold in such a way that it at least partially releases the blood flow in a radial direction through the central section and thus into an outgoing vessel.

[0018] To achieve efficient coverage of a lesion, the support body also features a membrane. The membrane is preferably attached exclusively to the 102025106826.7 M / CAN-433-PC 4

[0019] The membrane is arranged in the proximal and distal sections of the supporting body. In particular, the central section is free of membrane. This makes the central section permeable to blood in the radial direction.

[0020] The membrane covers the cells of the proximal and distal sections at least partially, and in particular completely. When implanted, the proximal and distal sections are preferentially positioned proximal and distal, respectively, of a branching vessel at a bifurcation. In this way, the membrane can cover lesions extending from the bifurcation into a vessel. Covering the lesion prevents plaque from detaching and entering the bloodstream.

[0021] The combination of the membrane and the covering element ensures that the support body can cover a lesion along its entire length. Specifically, each section of the support body is covered by the covering element and / or the membrane and can be used to treat a lesion. For example, the covering element can cover a lesion located near a bifurcation, particularly one substantially opposite a vessel branching off from a bifurcation. Furthermore, the membrane is preferably used to cover lesions extending from the bifurcation into a vessel.

[0022] In particular, the medical implant is suitable for treating carotid artery stenosis. The distal section of the implant can be positioned in the internal carotid artery in such a way that any stenosis located there is at least partially covered. The proximal section is preferably positioned in the common carotid artery. This means that the middle section, located between the proximal and distal sections, spans the external carotid artery. Blood flow into the external carotid artery is advantageously maintained by the covering element, which is loosely arranged in the region of the middle section and, when implanted, can extend at least partially into the external carotid artery. This ensures that, on the one hand, a carotid artery stenosis is covered, particularly completely, and on the other hand, blood flow into the external carotid artery is maintained. 102025106826.7 M / CAN-433-PC 5

[0023] Preferably, the support body is substantially tubular, particularly substantially cylindrical. The proximal and distal sections, as well as the middle section, are preferably substantially tubular. In particular, the proximal and distal sections, as well as the middle section, are substantially tubular in the manufactured state. The proximal and distal sections, as well as the middle section, are preferably tubular in such a way that adaptation to a vessel wall is possible in the implanted state. The tubular shape can also include a conical form. Furthermore, bulges (barrels) or flared longitudinal ends (flarings) can be included. Preferably, the proximal and distal sections, as well as the middle section, are at least partially cylindrical.

[0024] The medical implant features a support structure made of struts. These struts are composed of cells. The support structure is preferably a monolithic lattice structure, for example, a laser-cut lattice structure. Alternatively, the support structure can be formed by braiding one or more wires.

[0025] Preferred embodiments of the invention are specified in the dependent claims.

[0026] Preferably, the cover element has at least one substantially conical region that is loosely arranged in the area of ​​the central section. The cover element may have at least one region that has the shape of a cone or truncated cone. The conical region preferably extends from the proximal section of the support body in a distal direction, preferably to the transition between the central section and the distal section. The conical region is preferably flared in the radial direction of the cover element or the support body. The conical shape has proven particularly advantageous for ensuring that the cover element is loosely arranged in the area of ​​the central section. The conical region allows the cover element to allow blood flow in a radial direction through the central section by extending or unfolding into an outgoing vessel.This allows blood to flow through the central section into the outgoing vessel. Other shapes or geometries of the cover element are conceivable. 102025106826.7 M / CAN-433-PC 6.

[0027] During the insertion of the implant into a vessel, the conical portion of the cover element is preferably folded in such a way that it rests against the support body or the central section. Upon release of the implant, the conical portion unfolds. In the implanted state, the conical portion preferably extends into the outgoing vessel in such a way that blood flow into the outgoing vessel is permitted.

[0028] Furthermore, the cover element, in particular the conical region of the cover element, can have a cross-sectional diameter that changes in the axial direction. Specifically, the conical region of the cover element has a cross-sectional diameter that changes essentially continuously in the axial direction. The cross-sectional diameter increases, particularly continuously, in the distal direction of the cover element. The section of the conical region with the smallest cross-sectional diameter is preferably connected to the proximal section of the support body. From this point, the cross-sectional diameter of the conical region increases in the distal direction.

[0029] This advantageously achieves the effect that the cover element can span the central section without having direct connection points to the central section.

[0030] Preferably, the cover element has a larger cross-sectional diameter at its distal end than at its proximal end. The proximal end of the cover element is preferably connected to the proximal section of the support body. The distal end of the cover element is preferably arranged at the transition between the central and distal sections of the support body and forms a free end. In particular, the distal end of the cover element is loosely arranged at the transition between the central and distal sections. If the central section is positioned in a bifurcation, this arrangement of the cover element allows the distal end of the cover element to extend at least partially into an outgoing vessel of the bifurcation. This enables the cover element to allow blood flow in a radial direction through the central section and thus into the outgoing vessel. 102025106826.7 M / CAN-433-PC 7

[0031] The cover element can furthermore have a larger cross-sectional diameter than the support body, at least at its distal end. Advantageously, the proximal end of the cover element has essentially the same cross-sectional diameter as the proximal section of the support body. In particular, the cross-sectional diameter of the distal end of the cover element is at least twice the diameter of the support body. This allows the cover element, when implanted, to extend into an outgoing vessel and release blood flow in a radial direction through the central section and thus into the outgoing vessel.

[0032] The conical section of the cover element preferably exhibits an opening angle to the longitudinal axis of the cover element in its expanded, resting state. In particular, the opening angle is between 5° and 20°. This allows the implant to be adapted to different vascular anatomies. An opening angle of the conical section between 5° and 20° has proven particularly advantageous for treating lesions of the carotid artery. Other opening angles are conceivable.

[0033] The cover element advantageously has at least one substantially cylindrical section that is connected to the proximal section. The cylindrical section is preferably arranged on the membrane of the proximal section. The cylindrical section can be connected to the membrane of the proximal section. This ensures a secure connection of the cover element to the support body.

[0034] Preferably, the cover element has at least one slot extending axially. In particular, the at least one slot extends proximally from the distal end of the cover element. For example, the at least one slot extends over the entire length or a partial length of the conical section of the cover element. The length of the at least one slot can be adapted to the application. The at least one slot facilitates improved unfolding of the cover element into an outgoing vessel. Blood flow into the outgoing vessel can thus be maintained. 102025106826.7 M / CAN-433-PC 8

[0035] The cover element can have several slots extending in the axial direction. The multiple slots are preferably spaced apart from one another in the circumferential direction of the cover element and arranged in a substantially uniform manner. For example, the cover element can have two, three, four, five, or six slots extending in the axial direction of the cover element.

[0036] Alternatively or additionally, the cover element can have at least one slit extending circumferentially. The circumferential length of the slit is preferably at most one-third of the circumference of the cover element. In particular, the circumferential length of the slit corresponds essentially to the diameter of an outgoing vessel, for example, the external carotid artery. If the at least one slit is located at the transition to the outgoing vessel, in particular the external carotid artery, when implanted, blood can flow through the slit into the outgoing vessel, in particular the external carotid artery. This maintains the nutrient supply to the outgoing vessel, in particular the external carotid artery.

[0037] The cover element can have several slots extending in the circumferential direction of the cover element. The multiple slots are preferably arranged spaced apart from each other in the axial direction of the cover element.

[0038] For example, the cover element can have two, three, four, five or six slots extending in the circumferential direction of the cover element.

[0039] If the cover element includes both slots extending in the axial direction and slots extending in the circumferential direction, then those slots extending in the circumferential direction are preferably arranged between the slots extending in the axial direction.

[0040] In a particularly preferred embodiment, the cover element and / or the membrane is / are formed as an electrospun nonwoven fabric. The cover element and the membrane can be produced by electrospinning. By positioning the electrospun membrane and the electrospun cover element at a stenosis, an optimal 102025106826.7 M / CAN-433-PC 9

[0041] A covering effect is achieved. This prevents plaque from detaching and entering the bloodstream.

[0042] The electrospun nonwoven fabric is preferably formed from electrospun fibers arranged in an irregular, net-like pattern. The electrospun nonwoven fabric preferably has irregularly sized pores.

[0043] Preferably, the electrospun nonwoven fabric is formed from perfluorinated or partially fluorinated polymers (e.g., PTFE), polyurethane (e.g., thermoplastic polyurethane, hydrophilic polyurethane), polyamide (e.g., PA6.6), polyester (e.g., PLA, PLGA, PET), polysulfone (e.g., PSU), polyetheretherketone (PEEK), biological and / or protein-based polymers. Consequently, a wide variety of polymers can be selected for the production of the electrospun nonwoven fabric.

[0044] In the electrospinning process, a polymer solution is precisely metered at an emitter electrode. Applying an electric field creates a polymer jet that is accelerated towards a collector. This acceleration directs the polymer jet, forming a polymer fiber that becomes thinner with increasing length until it deposits onto the collector electrode (the support structure).

[0045] With regard to electrospun nonwoven fabric, reference is made to DE 10 2018 131 269 B4, which originates from the applicant.

[0046] Preferably, the central section is at least partially, and in particular largely, membrane-free. Preferably, between 50% and 95%, in particular at least 60%, in particular at least 70%, in particular at least 80%, and in particular at least 90% of the central section are membrane-free. Furthermore, the central section can be completely membrane-free. The membrane is advantageously limited substantially to the proximal and distal sections of the supporting body. This advantageously ensures that the central section is permeable to blood in the radial direction. If the central section is positioned in a bifurcation such that an outgoing vessel is spanned, the blood flow into the outgoing vessel can be maintained in the radial direction through the central section. 102025106826.7 M / CAN-433-PC 10

[0047] Furthermore, the central section can exhibit a greater porosity than the proximal and / or distal section. This advantageously ensures that the central section is sufficiently permeable to blood in the radial direction to maintain blood flow into an outgoing vessel. The porosity preferably describes the ratio of the projected surface area of ​​the webs to the total surface area of ​​the supporting body.

[0048] Preferably, the distal section of the support body features closed-cell design. This closed-cell design allows the distal section to be at least partially, and in particular completely, retracted for repositioning the implant within the vessel (resheathability). This enables the distal section to be repeatedly deployed from a catheter and at least partially retracted to align it correctly within the vessel.

[0049] The closed cells of the distal section are preferably essentially rhomboid in shape, with each rhomboid cell being defined by four ridges. The ridges are connected to each other at their intersection points by X-shaped ridge connectors.

[0050] Alternatively, the distal section of the supporting body features open cells (open cell design).

[0051] The distal section is preferably composed entirely of open cells. This open-cell design achieves excellent wall adaptation and high radial force, which is necessary to maintain stenosis patency in the implanted state. Furthermore, the foreshortening effect can be reduced by the open-cell design. This is preferably understood to mean that, due to the open-cell design, the support body shortens less during axial expansion than a comparable support body with a closed-cell design. This improves the accuracy of implant positioning within the vessel.

[0052] Furthermore, the proximal section may contain open cells. The proximal section preferably contains a combination of open and closed cells.102025106826.7 M / CAN-433-PC 11

[0053] Cells are incorporated. This allows for excellent wall adaptation even with a short proximal segment in the axial direction. For example, the proximal segment has closed cells at its proximal end, particularly a circumferential segment with closed cells. Distally, open cells adjoin the open cells of the proximal end. This forms a transition zone, which is particularly flexible, where closed and open cells merge. This flexible transition zone allows for decoupling of the distal end of the proximal segment from the rest of the proximal segment. The good wall adaptation of the proximal end of the proximal segment is thus virtually unaffected by the rest of the supporting structure. This advantageously leads to secure anchoring of the supporting structure within the vessel.

[0054] The central section of the support body preferably has closed cells (closed-cell design). The cells of the central section are preferably substantially rhomboid in shape. In particular, the cells of the central section have a connecting web that extends into the cell and bridges it diagonally. The additional connecting web can be incorporated into the design of the substantially rhomboid-shaped cell. The bridging of the cell by the connecting web is preferably understood to mean that the design of the base cell additionally includes at least one connecting web that extends across the entire base cell between two opposing webs. The connecting web can bridge or span the entire cell and connect the two opposing webs of a pair of webs.

[0055] The connecting bridge allows for easy optimization of the support body's bending flexibility without significantly impairing its support force or radial force. The connecting bridge enables excellent wall adaptation, particularly when the support body is bent, while maintaining high support force and radial force. Furthermore, the closed-cell design allows the implant to be at least partially retracted for repositioning within the vessel (resheathability). 102025106826.7 M / CAN-433-PC 12

[0056] Furthermore, the closed-cell design of the central section with its connecting bridge allows the radial force to be transmitted to adjacent cells in the axial direction. This is particularly advantageous in the region of a bifurcation, as the support body in this case only partially rests against the vessel wall. Thus, the support body does not rest against the vessel wall in the region of a branching vessel at the bifurcation. Consequently, the area of ​​the support body opposite the branching vessel lacks a directly opposing vessel wall segment that could act as a counterweight for generating radial force. To generate radial force in this area, the cells of the support body located proximal and distal to the branching vessel, which are fully enclosed by the vessel, can generate it and transmit it to the adjacent cells in the axial direction.

[0057] With regard to the cell design of the central section, reference is made to DE 10 2023 104 170 Al, which originates from the applicant.

[0058] The distal section preferably has a greater axial length than the proximal section and / or the middle section. This allows for good coverage of a lesion by the distal section.

[0059] The proximal section is preferably shorter in the axial direction than the distal section and / or the middle section. This advantageously results in good wall adaptation of the proximal section, ensuring secure anchoring of the support body within the vessel.

[0060] The distal section may have a smaller cross-sectional diameter than the proximal section. In this case, the middle section has a region where the cross-sectional diameters of the proximal and distal sections merge into one another.

[0061] Alternatively, the middle segment can have a larger cross-sectional diameter than the proximal and distal segments. This allows the middle segment to extend or bulge, at least partially, into a branching vessel of a bifurcation. 102025106826.7 M / CAN-433-PC 13

[0062] Advantageously, each section of the implant is individually customizable. This allows each section to have different dimensions, i.e., a different length in the axial direction and / or a different cross-sectional diameter. This enables the implant to be optimally adapted to a patient's vascular anatomy.

[0063] Furthermore, by changing the cross-sectional diameter along the longitudinal axis of the implant, it is possible to create a bulge in the support body. This bulge is preferably located on the section of the implant that, in its implanted state, is positioned at a branching vessel of a bifurcation. For example, the central section can include a bulge. Such stents, which feature a bulge, are commonly referred to as barrel stents.

[0064] Barrel stents are particularly suitable for treating lesions located near a bifurcation. The bulge of the barrel stent is preferably positioned within the bifurcation. This bulge allows for improved wall adaptation in the bifurcation area.

[0065] Preferably, at least one marker element is arranged at the transition between the middle section and the distal section. Alternatively or additionally, at least one marker element can be arranged at the transition between the proximal section and the middle section. Furthermore, at least one marker element can be arranged on each section of the support body.

[0066] For example, the proximal, distal, and mid-segments can each have a marker element. Furthermore, radiopaque end markers can be provided, particularly at the proximal and / or distal end of the support body. These marker elements ensure optimal radiographic visibility of the implant, allowing for ideal positioning within the lesion. This makes it easy for the surgeon to estimate the implant's placement within the vessel after its release from a catheter.

[0067] In a preferred embodiment, the marker elements can be designed as marker sleeves that can be firmly connected to the webs, in particular crimped onto the webs. Such marker sleeves exhibit 102025106826.7 M / CAN-433-PC 14

[0068] For example, compared to marker coils, they exhibit a higher X-ray density, resulting in improved X-ray visibility. Crimping the marker sleeves onto the ribs ensures a stable connection between the marker sleeves and the ribs.

[0069] The marker elements preferably consist of an X-ray-proof material, in particular platinum or a platinum alloy.

[0070] In another preferred embodiment, the implant comprises several cover elements arranged side by side in the axial direction of the support body. For example, the several cover elements can be arranged to overlap at least partially. This is preferably understood to mean that the distal end of a cover element, which is loosely arranged on the support body, at least partially overlaps the proximal end of an adjacent cover element. This advantageously ensures that the support body can serve to cover a lesion along its entire length.

[0071] In particular, each section of the supporting body is covered by the cover elements and / or the membrane and can be used to treat a lesion.

[0072] Alternatively, the multiple cover elements can be spaced apart from each other in the axial direction of the support body. In this case, it is possible that a section of the support body, located between two cover elements and unobstructed in relation to the cover elements, is covered with the membrane, in particular an electrospun membrane.

[0073] Each cover element is preferably designed such that it is connected to the support body at its proximal end and loosely arranged on the support body in a distal area, in order to at least partially allow blood flow in a radial direction through the support body when implanted. Each cover element can extend at least partially into an outgoing vessel when implanted. The cover elements can fold into the outgoing vessels in such a way that open areas are formed through which blood can flow into the outgoing vessels.

[0074] The number of cover elements and their arrangement on the support body can be adapted to the vascular anatomy. (See am102025106826.7 M / CAN-433-PC 15)

[0075] If the treatment site has multiple outgoing vessels, the number of cover elements can correspond to the number of outgoing vessels. For example, the implant can have at least two, in particular at least three, and in particular at least four, cover elements. Other numbers of cover elements are possible.

[0076] Alternatively, the cover element can be formed from at least two cover parts arranged side by side in the axial direction of the support body. The cover parts can overlap at least partially in the axial direction or be spaced apart from one another. The number of cover parts of the cover element is adaptable to the vascular anatomy. For example, the cover element can be formed from at least two, in particular at least three, and in particular at least four, cover parts. Each cover part is preferably designed such that it is connected to the support body at its proximal end and is loosely arranged on the support body in a distal area in order to at least partially allow blood flow in the radial direction through the support body when implanted.

[0077] The invention further relates to a method for manufacturing a medical implant. In the method, a compressible and expandable support body made of struts that delimit cells is first provided, wherein the support body comprises at least one proximal section, at least one distal section and at least one central section arranged between the proximal and distal sections.

[0078] Subsequently, a membrane is applied to the proximal and distal sections by electrospinning such that the cells of the proximal and distal sections are at least partially covered. The membrane is preferably applied selectively to the proximal and distal sections of the scaffold. Alternatively, it is possible to apply the membrane to the entire scaffold by electrospinning. The membrane can then be removed from the central section, for example, by cutting away the cells of the central section.

[0079] Subsequently, the middle section, which is particularly free of membrane, and the distal section are covered with at least one protective element.

[0080] Preferably, the protective element is essentially conical. Furthermore, the 102025106826.7 M / CAN-433-PC 16

[0081] The protective element is provided with a non-stick coating. To manufacture an implant with multiple cover elements or a cover element consisting of multiple cover parts, the central and distal sections are covered with several protective elements. The number of protective elements preferably corresponds to the number of cover elements or cover parts to be manufactured.

[0082] Subsequently, an electrospinning process is carried out to produce a cover element. The electrospinning process takes place at least on the proximal section and the at least one protective element. The cover element is thereby firmly bonded to the proximal section. The at least one protective element advantageously shields the middle section and the distal section from the electrospinning process. This prevents the cover element from bonding to the middle section and / or the distal section.

[0083] Subsequently, at least one slot can be made in the cover element such that the slot extends axially or circumferentially. The slot can be made, for example, with a mechanical cutting tool or a laser. The at least one protective element advantageously serves as protection for the membrane. Damage to the membrane during the slotting process is prevented by the protective element.

[0084] Finally, at least one protective element is removed. The cover element can then be loosely placed on the middle section.

[0085] The invention is explained in more detail with reference to exemplary embodiments in conjunction with the schematic drawings.

[0086] This shows

[0087] Fig. 1 shows a side view of the support body of a medical implant according to an embodiment of the invention, wherein the support body has a membrane at least partially; 102025106826.7 M / CAN-433-PC

[0088] Fig. 2 shows a side view of a medical implant according to an embodiment of the invention, wherein the implant has a cover element;

[0089] Fig. 3 shows a side view of a medical implant according to an embodiment of the invention, wherein the implant has a cover element with slots extending in the axial direction of the cover element;

[0090] Fig. 4 shows a perspective view of the medical implant according to Fig. 3;

[0091] Fig. 5 shows a side view of the medical implant according to Fig. 3, with the cover element in the compressed state.

[0092] Fig. 6a - 6c Side views of a medical implant according to an embodiment of the invention, wherein the implant has a cover element with slots extending in the circumferential direction of the cover element;

[0093] Fig. 7 shows the support body of a medical implant according to an embodiment of the invention in the implanted state;

[0094] Fig. 8 shows the medical implant according to Fig. 2 in the implanted state;

[0095] Fig. 9 shows the medical implant according to Fig. 2 in the implanted state;

[0096] Fig. 10 shows the medical implant according to Fig. 3 in the implanted state;

[0097] Fig. 11 shows the support body of a medical implant according to an embodiment of the invention in the implanted state, wherein the support body has marker elements;

[0098] Fig. 12 shows the support body of a medical implant according to an embodiment of the invention in the implanted state and a transport wire for feeding the implant; 102025106826.7 M / CAN-433-PC 18

[0099] Fig. 13 shows a side view of a medical implant according to an embodiment of the invention, wherein the implant comprises several cover elements;

[0100] Fig. 14 shows a partial section of the medical implant according to Fig. 13;

[0101] Fig. 15 shows a perspective view of the medical implant according to Fig. 13; and

[0102] Fig. 16 shows a side view of the support body of the medical implant according to a further embodiment according to the invention.

[0103] The same reference numbers are used below for identical or equivalent parts.

[0104] Fig. 2 shows a medical implant 10 according to an embodiment of the invention for the treatment of a local lesion in a vessel. The implant 10 is particularly suitable for the treatment of lesions located in or near a bifurcation. Specifically, the implant 10 serves to treat stenoses of the carotid artery. Other applications are possible.

[0105] Figures 2-6c show the medical implant 10 in its expanded resting state, i.e., when no external forces act on the implant 10. Figures 8-10 show the implant 10 in its implanted state. The implant 10 is inserted in the region of a bifurcation.

[0106] Fig. 1 shows that the medical implant 10 has a compressible and expandable support body 11. The support body 11 is formed from struts 15 that delimit cells 16. The support body 11 has a monolithic lattice structure that is produced by laser cutting.

[0107] In its expanded resting state, the support body 11 is essentially tubular (see Fig. 1). The support body 11 is shown in its implanted state in Figs. 7, 11, and 12. 102025106826.7 M / CAN-433-PC 19

[0108] The support body 11 comprises at least three sections 12, 13, 14. Specifically, the support body 11 comprises a proximal section 12, a distal section 13 and a central section 14, which is arranged between the proximal and distal sections 12, 13.

[0109] The proximal and distal sections 12, 13 each have a membrane 17 that covers the cells 16 of the proximal and distal sections 12, 13. The membrane 17 completely covers both the proximal and distal sections 12, 13. The membrane 17 is confined to the proximal and distal sections 12, 13 (see Fig. 1).

[0110] The implant 10 comprises a cover element 18, which is connected to the proximal section 12. Specifically, the cover element 18 is connected exclusively to the proximal section 12. Furthermore, the cover element 18 extends distally from the proximal section 12.

[0111] The cover element 18 is loosely arranged in the area of ​​the central section 14. The cover element 18 spans the central section 14 without having any direct connection points to the central section 14. Therefore, the cover element 18 is at least partially, and in particular largely, movable relative to the central section 14.

[0112] During the insertion of the implant 10, the cover element 18 is compressed onto the support body 11 (see Fig. 5). The cover element 18 rests fully against the support body 11. Upon release of the implant 10, the cover element 18 unfolds. Figs. 2-4, 6a-6c show the cover element 18 in its fully unfolded state.

[0113] The cover element 18 is arranged on the central section 14 such that, in the implanted state, blood flow in the radial direction through the central section 14 can be at least partially released. This ensures that blood flow into an outgoing vessel is at least largely maintained. Figures 8-10 show that, in the implanted state, the cover element 18 extends at least partially into the outgoing vessel. The cover element 18 opens into the outgoing vessel in such a way that it forms an open area through which blood can flow into the outgoing vessel. 102025106826.7 M / CAN-433-PC 20

[0114] Furthermore, the cover element 18 ensures efficient coverage of a lesion located near a bifurcation. Specifically, a lesion situated essentially opposite the outgoing vessel can be treated using the cover element 18. The cover element 18 is fixed on the side opposite the outgoing vessel between the vessel wall and the support body 11.

[0115] Specifically, Figures 8-10 show the implant 10 in its implanted state in the carotid artery. The distal section 13 is positioned in the internal carotid artery 101, thus covering any stenosis located there. The proximal section 12 is positioned in the common carotid artery 100. As a result, the central section 14, which is located between the proximal and distal sections 12, 13, spans the external carotid artery 102. Blood flow into the external carotid artery 102 is maintained by the covering element 18, which loosely spans the central section 14 and extends at least partially into the external carotid artery 102, allowing radial blood flow through the central section 14.

[0116] Figures 2-4, 6a-6c, 8, and 9 show that the cover element 18 has a substantially conical region 18a, which is loosely arranged in the region of the central section 14. The conical shape is particularly advantageous to ensure that the cover element 14 is movable relative to the central section 14.

[0117] Figures 8 and 9 illustrate that the cover element 18, in its implanted state, can extend or unfold through the cone-shaped area 18a into an outgoing vessel, thereby forming an open area through which blood can flow into the outgoing vessel.

[0118] Fig. 5 shows the cover element 18 in its compressed state, for example, during the insertion of the implant 10 into a vessel. The conical section 18a of the cover element 18 is folded in such a way that it rests against the support body 11 or the central section 14. Upon release of the implant 10, the conical section 18a unfolds and assumes the shape shown in Figs. 2-4, 6a-6c, 8, and 9. 102025106826.7 M / CAN-433-PC 21

[0119] The cover element 18, or rather the conical region 18a of the cover element 18, has a cross-sectional diameter that changes in the axial direction. Specifically, the cross-sectional diameter of the cover element 18 increases essentially continuously in the distal direction.

[0120] The cover element 18 has a larger cross-sectional diameter at a distal end 18d than at a proximal end 18c. The proximal end 18c of the cover element 18 is connected to the proximal section 12 of the support body 11. The distal end 18d of the cover element 18 is located at the transition between the central section 14 and the distal section 13 of the support body 11 and forms a free end that is loosely attached to the support body 11 (see Figs. 2-4, 6a-6c).

[0121] In the implanted state, the distal end 18d of the cover element 18 extends at least partially into an outgoing vessel of the bifurcation (see Figs. 8 and 9). This allows the cover element 18 to release blood flow in a radial direction through the central section 14 and thus into the outgoing vessel.

[0122] Figures 2-4 and 6a-6c further show that the cover element 18 has a larger cross-sectional diameter at its distal end 18d than the support body 11. This allows the cover element 18, when implanted, to extend away from the support body 11 into an outgoing vessel and allow blood flow into that vessel.

[0123] The proximal end 18c of the cover element 18 has essentially the same cross-sectional diameter as the proximal section 12 of the support body 11 (see Fig. 2 - 4 and 6a - 6c).

[0124] The conical area 18a of the cover element 18 has an opening angle to the longitudinal axis of the cover element 18 in its expanded resting state. Specifically, the opening angle is between 5° and 20°. This is particularly advantageous for the treatment of carotid artery lesions.

[0125] Figures 2-4 and 6a-6c further show that the cover element 18 has a substantially cylindrical section 18b which is connected to the proximal section 12 of the support body 11. (102025106826.7 M / CAN-433-PC 22)

[0126] cylindrical area 18b is arranged on or connected to the membrane 17 of the proximal section 12.

[0127] Figures 3 and 4 show that the cover element 18 has several slots 19a extending axially along the cover element 18. The slots 19a extend proximally from the distal end 18d of the cover element 18. Specifically, the slots 19a extend over the entire length of the conical section 18a of the cover element 18. The slots 19a facilitate improved folding of the cover element 18 into an outgoing vessel (see Figure 10).

[0128] The multiple slots 19a are spaced apart from one another in the circumferential direction of the cover element 18 and are arranged in a substantially uniform distribution (see Fig. 4). Specifically, the cover element 18 has four slots 19a extending in the axial direction of the cover element 18.

[0129] The embodiments shown in Figures 6a-6c demonstrate that the cover element 18 has at least one slot 19b extending circumferentially. Figure 6a shows that the cover element 18 has one slot 19b extending circumferentially. Figure 6b shows that the cover element 18 has two slots 19b extending circumferentially and spaced apart and offset from each other axially.

[0130] According to Fig. 6c, the cover element 18 comprises both slots 19a extending axially along the cover element 18 and slots 19b extending circumferentially along the cover element 18. The slots 19b extending circumferentially along the cover element 18 are arranged between the slots 19a extending axially along the cover element 18.

[0131] The cover element 18 and the membrane 17 are formed as electrospun nonwoven fabric. The electrospun nonwoven fabric is made of a polymer. The cover element 18 and the membrane 17 are produced by electrospinning. 102025106826.7 M / CAN-433-PC 23

[0132] The cover element 18 and the membrane 17 are formed from electrospun fibers arranged in an irregular, net-like pattern. The electrospun fibers define irregularly sized pores.

[0133] Fig. 1 illustrates that the central section 14 is membrane-free. For clarity, the implant 10 is shown in Fig. 1 without the cover element 18. It can be seen that the membrane 17 is limited to the proximal and distal sections 12, 13 of the support body 11. This makes the central section 14 permeable to blood in the radial direction.

[0134] Fig. 7 shows that the central section 14 has a porosity that is greater than the porosity of the proximal and distal sections 12, 13. This ensures that the central section 14 is sufficiently permeable to blood in the radial direction to maintain blood flow into an outgoing vessel when implanted.

[0135] In the embodiment shown in Fig. 16, the distal section 13 of the support body 11 has closed cells 16a (closed cell design). This allows the distal section 13 to be at least partially retracted for repositioning the implant 10 in the vessel (resheathability).

[0136] The closed cells 16a of the distal section 13 are essentially rhomboid-shaped and each has four rhombic points. Four ribs 15 form each closed cell 16a. The closed cells 16a are connected circumferentially and axially at their rhombic points to adjacent closed cells 16a by X-shaped rib connectors.

[0137] In the embodiments shown in Figures 1 to 15, the distal section 13 of the support body 11 has open cells 16b (open cell design). Specifically, the distal section 13 is formed exclusively from open cells 16b. This results in very good wall adaptation and high radial force in the distal section 13. Furthermore, the foreshortening effect can be reduced by the open cell design.

[0138] The open cells 16b of the distal section 13 are rhomboid in shape and each has four rhomboid points. Four ridges 15 each form a 102025106826.7 M / CAN-433-PC 24

[0139] Open cell 16b. The open cells 16b are connected circumferentially at their rhombic tips to adjacent open cells 16b. Furthermore, the open cells 16b are at least partially unconnected at those rhombic tips that point axially to the distal section 13.

[0140] The proximal section 12 exhibits a combination of open and closed cells 16a, 16b. This results in very good wall adaptation of the proximal section 12 despite its short axial length.

[0141] The central section 14 of the supporting body 11 has closed-cell design cells 16a. The cells 16a of the central section 14 are essentially rhomboid in shape and have a connecting web that extends into the cell 16a and bridges it diagonally. The connecting web spans the entire cell 16a and connects the two opposing webs of a web pair.

[0142] Fig. 11 shows that several marker elements 20 are arranged at the transition between the middle section 14 and the distal section 13. The marker elements 20 ensure optimal radiographic visibility of the implant 10. This allows for ideal positioning of the implant 10 in the area of ​​the lesion.

[0143] Figure 12 shows that a transport wire 50, used to guide the implant 10, has a marker element 20. The implant is positioned on the transport wire 50 such that the transition between the central section 14 and the distal section 13 is located in the area of ​​the marker element 20. This allows the implant 10 to be positioned precisely.

[0144] Figures 13-15 show that the implant 10 has several cover elements 18 arranged side by side in the axial direction of the support body 11. It can be seen that each cover element 18 is connected to the support body 11 at its proximal end and is loosely arranged on the support body 11 in a distal area. 102025106826.7 M / CAN-433-PC 25

[0145] Due to the loose arrangement of the distal areas of the cover elements 18, each cover element 18, in its implanted state, can at least partially allow blood flow in a radial direction through the central section 14 of the support body 11. In its implanted state, each cover element 18 extends at least partially into an outgoing vessel. The cover elements 18 open into the outgoing vessels in such a way that open areas are formed through which blood can flow into the outgoing vessels.

[0146] Each cover element 18 has a substantially conical region 18a which is loosely arranged on the support body 11. Furthermore, each cover element 18 has a cylindrical region 18b which is connected to the support body 11.

[0147] According to Figs. 13-15, the implant 11 has three cover elements 18. The number of cover elements 18 is adapted to the number of outgoing vessels.

[0148] Figures 13 and 15 further show that the cover elements 18 have slots 19a extending in the axial direction of the cover elements 18. The slots 19a facilitate improved folding of the cover elements 18 into outgoing vessels.

[0149] Fig. 14 illustrates that those areas of the support body 11 spanned by the conical sections 18a of the cover elements 18 are at least partially membrane-free. Specifically, the central section 14 and parts of the distal section 14 are membrane-free. The support body 11 is permeable to blood in the radial direction in the membrane-free areas. 102025106826.7 M / CAN-433-PC

[0150] List of references

[0151] 10 implants

[0152] 11 Support bodies

[0153] 12 proximal section of the supporting body

[0154] 13 distal section of the support body

[0155] 14 Middle section

[0156] 15 bridges

[0157] 16 cells

[0158] 16a closed cells

[0159] 16b open cells

[0160] 17 Membran

[0161] 18 Cover element

[0162] 18a conical area of ​​the cover element 18b cylindrical area of ​​the cover element 18c proximal end of the cover element

[0163] 18d distal end of the cover element

[0164] 19a, 19b Slot

[0165] 20 Marker elements

[0166] 50 Transport wire

[0167] 100 Common Carotid Artery

[0168] 101 Internal Carotid Artery

[0169] 102 External Carotid Artery

Claims

102025106826.7 M / CAN-433-PC 27 Claims 1. Medical implant (10) for treating a local lesion in a vessel, in particular in a bifurcation of a vessel, comprising a compressible and expandable support body (11) made of struts (15) that delimit cells (16), wherein the support body (11) comprises at least one proximal section (12), at least one distal section (13) and at least one intermediate section (14) arranged between the proximal and distal sections (12, 13), wherein the proximal and distal sections (12, 13) have a membrane (17) that at least partially covers the cells (16) of the proximal and distal sections (12, 13), characterized by the fact that the implant (10) comprises at least one cover element (18) which is connected to the proximal section (12) and is loosely arranged in the area of ​​the middle section (14) in order to at least partially release the blood flow in a radial direction through the middle section (14) when implanted.

2. Medical implant (10) according to claim 1, characterized in that the cover element (18) has at least one substantially conical area (18a) which is loosely arranged in the area of ​​the central section (14).

3. Medical implant (10) according to claim 1 or 2, characterized in that the cover element (18), in particular the conical area (18a) of the cover element (18), has a cross-sectional diameter that changes in the axial direction, in particular essentially continuously.

4. Medical implant (10) according to one of the preceding claims, characterized in that The cover element (18) has a larger cross-sectional diameter at a distal end (18d) than at a proximal end (18c). 102025106826.7 M / CAN-433-PC 28 5. Medical implant (10) according to one of the preceding claims, characterized in that the cover element (18) has a larger cross-sectional diameter than the support body (11) at least at one distal end (18d).

6. Medical implant (10) according to one of claims 2 to 5, characterized in that the cone-shaped area (18a) of the cover element (18) in the expanded rest state has an opening angle to the longitudinal axis of the cover element (18), wherein the opening angle is in particular between 5° and 20°.

7. Medical implant (10) according to one of the preceding claims, characterized in that the cover element (18) has at least one substantially cylindrical area (18b) which is connected to the proximal section (12).

8. Medical implant (10) according to one of the preceding claims, characterized in that the cover element (18) has at least one slot (19a) which extends in the axial direction of the cover element (18).

9. Medical implant (10) according to one of the preceding claims, characterized in that the cover element (18) has at least one slot (19b) which extends in the circumferential direction of the cover element (18).

10. Medical implant (10) according to one of the preceding claims, characterized in that the cover element (18) and / or the membrane (17) is / are designed as an electrospun nonwoven fabric.

11. Medical implant (10) according to one of the preceding claims, characterized in that the central section (14) is at least partially membrane-free. 102025106826.7 M / CAN-433-PC 29 12. Medical implant (10) according to one of the preceding claims, characterized in that the middle section (14) has a porosity that is greater than the porosity of the proximal and / or distal section (12, 13).

13. Medical implant (10) according to one of the preceding claims, characterized in that the distal section (13) of the supporting body (11) has closed or open cells (16a, 16b).

14. Medical implant (10) according to one of the preceding claims, characterized in that the proximal (13) of the supporting body (11) has open cells (16b).

15. Medical implant (10) according to any one of the preceding claims, characterized in that the central section (14) of the supporting body (11) has closed cells (16a), wherein the cells (16) of the central section (14) are essentially diamond-shaped and in particular have a connecting web that extends into the cell (16a) and bridges it diagonally.

16. Medical implant (10) according to one of the preceding claims, characterized in that at least one marker element (20) is arranged at the transition between the proximal section (12) and the middle section (14) and / or at the transition between the middle section (14) and the distal section (13).

17. Medical implant (10) according to one of the preceding claims, characterized in that the implant (10) comprises several cover elements (18) arranged side by side in the axial direction of the support body (11), or the cover element (18) is formed from at least two cover parts arranged side by side in the axial direction of the support body (11). 102025106826.7 M / CAN-433-PC 30 18. Method for manufacturing a medical implant (10), in particular according to one of the preceding claims, wherein the method comprises the following steps: - Providing a compressible and expandable support body (11) made of struts (15) that delimit cells (16), wherein the support body (11) comprises at least one proximal section (12), at least one distal section (13) and at least one middle section (14) that is arranged between the proximal and distal sections (12, 13); - Applying a membrane (17) to the proximal and distal section (12, 13) by an electrospinning process such that the cells (16) of the proximal and distal section (12, 13) are at least partially covered; - Covering the central section (14) and the distal section (13) with a protective element, in particular one that is essentially conical; - Carrying out an electrospinning process to produce a cover element (18) at least on the proximal section (12) and the protective element such that the cover element (18) is connected to the proximal section (12); - Removal of the protective element.

19. Method for manufacturing a medical implant according to claim 18, characterized by the fact that The procedure includes the following step: - Including at least one slot (19a, 19b) in the cover element (18) such that the at least one slot (19a, 19b) extends in the axial direction or in the circumferential direction of the cover element (18).

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