Medical kit, medical system and covering device for treating an aneurysm

Abstract

The invention relates to a medical kit for treating a vascular malformation, in particular an aneurysm and / or a fistula, having a durable implantable covering device (12), in particular a stent, for covering the vascular malformation, wherein the covering device (12) has a tubular, self-expandable mesh structure (14) and a covering (20) made of an electrospun fabric, wherein the covering (20) is connected to the mesh structure (14) and at least partially covers the mesh structure (14) in order to be placed over the vascular malformation in an implanted state, and an embolization medium (40) which can be applied for treating the vascular malformation in the implanted state by means of a delivery device (44), wherein the covering (20) forms a porous membrane which can be penetrated by the delivery device (44) for applying the embolization medium (40) and is adapted to lie against the outer circumference of the delivery device (44) in a penetrated state.

Description

TECHNICAL FIELD

[0001] The present invention relates to a medical set for treating vascular malformations, in particular aneurysms and / or fistulas. The invention further relates to a medical system and a covering device for treating vascular malformations. BACKGROUND

[0002] WO 2014 / 177634 A1 describes a highly flexible stent having a compressible and expandable mesh structure, wherein the mesh structure is configured in one piece. The mesh structure comprises closed cells, which are each defined by four mesh elements. The mesh structure has at least one cell ring, which comprises three to six cells.

[0003] Furthermore, it is known from the applicant's practice that stents having a mesh structure formed from individual wires are known. The wires themselves are interwoven to form a tubular braid. At the axial ends of the tubular braid, the wires are turned around, thereby forming atraumatic loops. The axial ends can be widened into a funnel shape.

[0004] The known medical devices are particularly suitable for treating aneurysms in small cerebral blood vessels. Such blood vessels have a very small cross-sectional diameter and are often highly meandering. For this purpose, the known stents are designed to be highly flexible, so that they can be compressed to a very small cross-sectional diameter on the one hand and have a high bending flexibility on the other hand, which enables the delivery into small cerebral blood vessels.

[0005] For treating aneurysms in cerebral blood vessels, it is advantageous to use a stent which spans over the aneurysm and blocks the aneurysm from the blood flow within the blood vessel. To achieve this, it is known to provide the stent with a covering which closes the cells of the stent, thereby preventing the blood flow into the aneurysm.

[0006] Another complementary or alternative treatment method for aneurysms is to implant so-called coils into the aneurysm, which leads to the blood clotting there. The resulting thrombus impedes the blood circulation in the aneurysm, thereby preventing the risk of rupture and subsequent bleeding.

[0007] However, especially in the case of wide-necked aneurysms, the coils easily migrate into the blood vessel system during implantation, thus causing an occlusion of the main vessel lumen. In the "ballon assisted coiling" technique, a catheter with a "compliant balloon" is positioned in the blood vessel, in particular at the level of the aneurysm neck. The balloon, which is filled with contrast agent, closes the aneurysm neck during coil placement and forces the coils to be arranged tightly within the aneurysm space. Since the coils are plastically deformable, they retain their shape. Even if the balloon is removed, the coils do not leave the aneurysm. However, there is a problem here, in particular due to the fact that the balloon closes the blood vessel. If the operation takes a long time (in the case of large aneurysms, several coils have to be placed, the operation can last for several minutes), the blood flow is completely interrupted over time. Although collateral vessels ensure the supply to the downstream tissue, the risk of insufficient perfusion remains.

[0008] Furthermore, during the operation, the catheter through which the coil is guided is "locked" (i.e. clamped) on one side of the balloon. If the coil catheter needs to be replaced (for example in the event of damage) before the operation has been completed, the balloon should be discharged in order to be able to withdraw the catheter. In this phase, the coils, which are not yet completely and tightly located in the blood vessel, can move. These moving coils can then cause an occlusion of the blood vessel. SUMMARY

[0009] Against this background, it is the task of the present invention to provide a medical kit for treating a vascular malformation, with which at least the risk of occlusion of the blood vessel is reduced. It is a further task of the present invention to provide a medical system.

[0010] According to the invention, the tasks in the context of a medical kit, a medical system and a covering device are achieved by the subject matter described below.

[0011] In particular, the task is achieved by a medical kit for treating a vascular malformation, in particular an aneurysm and / or a fistula (for example a carotid direct cavernous fistula). The kit has a permanently implantable covering device, in particular a stent, for covering the vascular malformation. The covering device has a tubular, self-expandable mesh structure and a covering made of an electrospun fabric. The covering is connected to the mesh structure and at least partially covers the mesh structure to be placed over the vascular malformation in the implanted state. The medical kit has an embolisation medium which can be applied for treating the vascular malformation by a delivery device in the implanted state. The covering forms a porous membrane which can be penetrated by the delivery device with which the embolisation medium is applied and which is adapted to lie against the outer circumference of the delivery device in the penetrated state.

[0012] The medical kit according to the application thus comprises a covering device and an embolization medium. The kit can comprise further components.

[0013] Unlike the medical kit according to DE 10 2019 121 546 of August 9, 2019, the medical kit according to the application is provided for permanently, not only temporarily, covering an aneurysm. The covering device forms a permanent implant, for example a stent. For this purpose, the permanently implantable covering device is placed in the known manner by means of a transport wire through a delivery device over the aneurysm to be treated. After the covering device has been completely released from the delivery device, the covering device is detached from the transport wire. The covering device is thus firmly and permanently anchored in the blood vessel and cannot be pulled back into the delivery device in the finally implanted state.

[0014] For this purpose, the covering device is detachably connected to the transport wire upon introduction.

[0015] Preferably, the covering device is a stent. Typically, the covering device has a tubular and self-expandable mesh structure. The mesh structure is open at a distal end and at a proximal end, i.e. at both axial ends, so that in the expanded state blood can flow through the mesh structure in the known manner. Unlike this, known thrombectomy devices for pulling back into a catheter have an inwardly closed funnel-shaped portion which is fixedly, i.e. not detachably, connected to the transport wire.

[0016] The covering on the mesh structure formed by the electrospun fabric has an Ausdehnung, so that the vascular malformation, in particular the aneurysm, can be sufficiently safely covered in the implanted state. Here, the covering can extend over the entire circumference of the mesh structure and extend a sufficiently large length in the axial direction of the mesh structure. The covering can also not extend over the entire circumference, but only over a partial circumference of the mesh structure, in particular over a corner segment of the mesh structure and / or over a partial length.

[0017] The covering is connected to the mesh structure so that the covering cannot be separated from the mesh structure in the implanted state. The electrospun fabric of the covering covers the mesh structure.

[0018] Typically, the embolization medium is an embolization medium suitable for treating a vascular malformation. For example, an embolization medium which can be introduced into an aneurysm to cause it to atrophy is, without limitation, one or more coils and / or an embolic liquid, for example a viscous hydrogel.

[0019] According to the present application, the covering, in particular the electrospun fabric of the covering, forms a porous membrane. Here, the entire covering, in particular the electrospun fabric of the covering, can form a porous membrane. It is also possible that only a portion of the covering forms a porous membrane.

[0020] The porous membrane is configured such that it can be penetrated by a delivery device for applying embolization media. In other words, the porous membrane is configured such that the delivery device can be radially or at an acute angle pierced outwards through the membrane from the lumen of the implanted mesh structure. Here, the delivery device pierces or penetrates the membrane without irreversibly damaging the covering or the fabric. Here, the individual pores of the fabric can be sharply expanded or enlarged.

[0021] It has been shown that the electrospun fabric is sufficiently flexible such that when the delivery device penetrates the electrospun fabric, the plurality of pores or one pore present in the electrospun fabric is elastically expanded by the delivery device. Here, the plurality of pores or one pore is deformed and the membrane material arranged around the pores is elastically deformed such that a sufficiently large opening for the delivery device is created. The delivery device itself has a diameter that is several orders of magnitude larger than the diameter of the pores. The electrospun fabric or the porous membrane is elastic such that the pores can be deformed enough for the delivery device to pass through.

[0022] For example, the above exemplary diameter order of the delivery device is based on a pore size (inner diameter) of 5-20 pm for a mesh structure spun for 1 minute or a pore size (inner diameter) of 1-5 pm for a mesh structure spun for 2 minutes for the covering or the veil.

[0023] For this purpose, the outer diameter of a suitable delivery device (e.g., a guidewire with a subsequent microcatheter) can be described as follows:

[0024] Outer diameter of the guidewire: about 0.36 mm (0.014")

[0025] Outer diameter of the microcatheter: about 2.1 Fr (0.70 mm)

[0026] Inner diameter (ID) of the microcatheter: about 0.42 mm (0.0165")

[0027] A smaller combination of an outer diameter of the guidewire of about 0.254 mm (0.010") and an outer diameter of the microcatheter of about 1.5 Fr (0.5 mm) and an ID of 0.33 mm (0.013") is possible.

[0028] The above-mentioned size ratios are exemplary. Other size ratios of the pores and the delivery device are possible.

[0029] In this state, i.e. when the delivery device penetrates the membrane, the porous membrane of the covering or electrospun fabric rests against the outer circumference of the delivery device and thus seals the delivery device with respect to the vascular malformation, in particular the aneurysm. The embolization medium can then be transported through the membrane by the delivery device into the aneurysm. Here, the delivery device is arranged in the lumen of the covering device or stent. By the membrane function of the covering or fabric, the embolization medium is enabled to be introduced into the aneurysm by the delivery device through the lumen of the covering device radially or at an acute angle from the inside to the outside through the wall or mesh structure of the covering device.

[0030] The sealing of the delivery device by the fabric or covering prevents the embolization medium from possibly entering the vascular system upon introduction into the aneurysm.

[0031] After the aneurysm has been sufficiently filled with embolization medium, the delivery device can be removed through the lumen of the mesh structure. Here, the flexibility of the covering or electrospun fabric again facilitates the removal of the delivery device in the case that the embolization medium cannot escape from the aneurysm.

[0032] The membrane function of the covering or fabric can be described as follows. On the one hand, the covering or fabric is slightly porous, so that in the implanted state of the covering device the embolization medium is blocked in the aneurysm by the covering. On the other hand, the covering or fabric is open-pored and flexible, so that the delivery device (e.g. a microcatheter) is guided through the covering or fabric without damaging the covering or fabric or detaching it from the stent support structure or generally the mesh structure.

[0033] In the electrospun fabric, the pores are usually designed to be irregular. In any case, the manufacturing method does not allow the production of pores of a similar patterned arrangement or design. However, the pore size can be adjusted at least according to the process parameters to ensure that at least a portion of the pores have a certain minimum size.

[0034] For example, the electrospinning process can be carried out directly on the mesh structure, thus establishing a connection to the mesh structure at the same time as the covering is formed. The covering can be connected to the mesh structure in a material-locked manner. For example, the covering can be connected to the mesh structure by an adhesive connection. The adhesive connection can be established by means of an adhesion promoter. For example, the adhesion promoter can comprise or consist of polyurethane.

[0035] Furthermore, the cover made of the electrospun fabric is very thin and flexible, which has little or no influence on the flexibility of the grid structure. In particular, unlike the previously known covers made of textile material, the cover hardly impedes the compression of the grid structure. Thus, overall, the entire covering device can be compressed to a significantly smaller cross-sectional diameter and thus be guided through a small catheter into particularly small blood vessels. In particular, this is of great relevance for the treatment of aneurysms in the cerebral vessels, for which the present application is particularly suitable.

[0036] Thus, with the medical kit according to the application, a treatment in a blood vessel can also be carried out, which has not been possible with the previously known medical devices having a grid structure and a cover. Due to the high compressibility of the covering device, very small delivery forces occur in the delivery through the catheter or the usual delivery means. In particular, the delivery forces when delivering the covering device are even the same as compared to the delivery of the grid structure without the cover.

[0037] Furthermore, the covering device advantageously arranged at the treatment site, i.e. at the level of the aneurysm, during and after the placement of the coil can prevent the coil from being moved out of the aneurysm and thus also at least greatly reduces and preferably excludes the risk of a blood vessel occlusion caused by the coil.

[0038] The cover is porous and in particular blood-permeable. In this context, "porous" can be understood as the cover or the electrospun fabric being net-like or being configured as a net. This is based on the idea that cells located in the area of the cover can be supplied with blood and thus with nutrients, so that a supply deficiency does not occur when or after the placement of the coil.

[0039] Thus, the medical kit according to the application enables a good blockage of the aneurysm to block off embolization media, for example the coil, inserted into the aneurysm, but at the same time allows the entry of nutrients into the aneurysm. The nutrient supply into the branch vessels and the adjacent blood vessel inner wall is also achieved by the medical kit, which is covered by the cover. The cover formed by the electrospun fabric enables a coverage of the aneurysm, but at the same time also allows a certain blood permeability. This permeability is advantageous for the supply of nutrients to the cells of the aneurysm wall. Thereby, a cell degeneration and thus a possible aneurysm rupture is avoided.

[0040] The advantages of the present application are not only applicable to the treatment of aneurysms, but also to the treatment of other blood vessel malformations, for example fistulas, for example carotid artery direct cavernous fistulas.

[0041] The present application also has various other advantages.

[0042] In conventional treatment methods using, for example, a shunt, the introduction of the coil or the embolizing liquid can only be planned in advance. For this purpose, the second catheter is usually first introduced into the aneurysm, and then the stent or shunt is placed in front of the aneurysm neck and above the second catheter. The second catheter is located radially outside the stent or shunt between the catheter wall and the vessel wall. Then, the coil or the liquid embolizing agent can be introduced into the aneurysm through the second catheter. When the aneurysm is sufficiently filled, the second catheter is removed.

[0043] Subsequently, it is no longer possible to wind the coil or to deliver the liquid embolizing agent, since there is no access to the aneurysm without the second catheter.

[0044] In contrast, the invention offers the advantage that the electrospun fabric assumes the function of a membrane. This gives the user more operating space during the application, even after several months or years.

[0045] The covered device, in particular the covered stent, covered with the electrospun fabric is first placed over the aneurysm neck. Subsequently, or at a later point in time if necessary, the delivery device, in particular the microcatheter that has already been used to deliver the stent, can be used to penetrate through the covered fabric layer. For this purpose, for example, a stiff guidewire, preferably of gauge 0.014" or 0.012" or 0.010", is inserted into the microcatheter and, if necessary, shaped at the tip beforehand (e.g. 90° bend, narrow radius). Now, the guidewire can be used to puncture any stent cell, or usually a cell of the mesh structure covering the aneurysm neck. Once the cell has been successfully punctured, the microcatheter on the guidewire can be pushed through the cell into the aneurysm. Then, the guidewire is removed so that the coil or the liquid embolizing agent can be delivered through the catheter.

[0046] Here, the fabric reacts like a membrane, tightly adhering around the guidewire or microcatheter and at the same time preventing the embolizing medium (e.g. coil or embolizing agent) from escaping into the vascular system.

[0047] The introduction of the embolizing medium into the aneurysm with the kit according to the invention takes place after the implantation of the covered device. The time interval is variable and can even be several months or years. The second catheter placed before the implantation of the covered device is dispensed with. Optionally, the microcatheter can be used directly after the stent has been lowered to puncture the membrane and deliver the embolizing agent or usually the embolizing medium. Thus, the invention significantly simplifies the introduction of the embolizing medium into the aneurysm, since the implantation of the covered device and the introduction of the embolizing medium into the aneurysm can be carried out with the same delivery device.

[0048] The combination of the kit according to the invention with a delivery system is disclosed and claimed.

[0049] The covering device according to the present application is disclosed and claimed independently of the embolization medium and the delivery device. Thus, the covering device according to the present application is neither limited to the embolization medium nor to the delivery device.

[0050] Preferred design solutions, refinements and variants are described in the following.

[0051] Thus, the porous membrane of the covering can be adapted to at least partially retract the opening formed by the delivery device when passing through the membrane after removal of the delivery device.

[0052] After the aneurysm has been sufficiently filled with coils / embolization agent, the delivery device, in particular a microcatheter, can be safely pulled out of the aneurysm. The properties of the membrane cause the openings of the cells of the mesh structure, in particular the stent cells, to be immediately closed to prevent the coils or embolization agent from escaping into the cerebral vessels. Here, it is not necessary to completely close the cells of the mesh structure to produce this effect.

[0053] In other words, once the delivery device has been completely removed from the aneurysm and thus pulled out of the covering or fabric, the covering or fabric is at least partially closed again. Due to the elasticity of the fabric, the flexible openings in the covering or fabric, which were expanded for the delivery device, at least partially retract, so that the fabric forms a substantially closed but porous covering, which safely blocks the embolization medium arranged in the aneurysm. Thus, the covering forms a porous membrane, which is pierced or penetrated by the delivery device for introducing the embolization medium into the aneurysm and seals the delivery device upon introduction. After removal of the delivery device, the membrane is closed again, thereby blocking the embolization medium in the aneurysm. In order to be able to block the embolization medium, it is not necessary to be completely closed. In a further preferred embodiment it is provided that the porous membrane of the covering is adapted to retract the openings to a maximum of 80%, in particular a maximum of 60%, in particular a maximum of 40%, in particular a maximum of 20% of the diameter of the delivery device.

[0054] The retracted openings are smaller than the outer diameter of the delivery device, which penetrates the membrane.

[0055] Preferably, the covering is slightly porous, so that the covering blocks the applied embolization medium in the implanted state.

[0056] Advantageously, the mesh structure has or is preferably formed of a shape memory alloy, in particular Nitinol or other shape memory alloys. The mesh structure can be woven or made by laser cutting. For cerebral applications, a woven mesh structure is preferred.

[0057] Preferably, in order to achieve sufficient flexibility of the cover, the cover is formed by irregularly meshed threads having a thread thickness of between 0.1 pm and 3 pm, in particular between 0.2 pm and 2 pm, in particular between 0.5 pm and 1.5 pm, in particular between 0.8 pm and 1.2 pm.

[0058] Preferably, the thread thickness of the threads can be at most 2 pm, in particular at most 1.5 pm, in particular at most 1 pm and at least 0.3 pm.

[0059] Advantageously, the porosity of the cover is at most 70%, in particular at most 50%, in particular at most 40%, in particular at most 30%. Thereby, on the one hand, the stability of the cover with respect to forces acting on the cover, for example when the coil or the embolization medium is inserted into an aneurysm, is improved with respect to the coil or the embolization medium. On the other hand, the stability of the cover with respect to the breaking stability is advantageously optimized.

[0060] In one embodiment, the porosity of the cover is at least 5%, in particular at least 10%, in particular at least 20%, in particular at least 30%, in particular at least 40%, and in particular at least 45%. This embodiment is based on the idea that, as described above, the existing porosity reaching the above-mentioned percentage levels can ensure the supply to, for example, side vessels or vessel walls near an aneurysm during and after the placement of the embolization medium.

[0061] Furthermore, the cover is particularly suitable for microcatheters due to its porosity, since the cover is compressible and thus can be passed through the microcatheter to the treatment site with low friction and can also be guided back. Here, a microcatheter can be understood to be a catheter having an inner diameter in the range of 0.3 mm to 0.75 mm.

[0062] The above-mentioned upper and lower limits can be combined into ranges, if appropriate.

[0063] According to an advantageous design, the cover extends over the entire circumferential face of the mesh structure. Thereby, the above-mentioned advantages are advantageously optimized, in particular with respect to the stability of the cover and thus of the mesh structure.

[0064] According to an advantageous refinement, the cover extends over a portion of the circumference of the grid structure, in particular over at most 70%, in particular at most 60%, in particular at most 50%, in particular at most 40%, in particular at most 30%. Preferably, the cover thus extends only over the treatment site, i.e. for example only over the opening of the aneurysm. By this refinement, on the one hand it is ensured that the opening of the aneurysm is sufficiently closed for the coil placed therein to be fixed. On the other hand, it is thereby also ensured that cells and / or side vessels which are located in particular at the level of the aneurysm can be better and continue to be supplied with blood and thus with nutrients due to the lack of cover.

[0065] According to an additional or alternative embodiment, the cover extends over at least 80%, in particular at least 90%, in particular 100% of the length L of the grid structure. The length L corresponds to the total length of the covering device, in particular of the implant.

[0066] This embodiment is in particular suitable for fusiform or long-necked aneurysms which are to be covered over a longer portion. Here, a fusiform aneurysm is to be understood as an aneurysm which extends over at least 50%, in particular at least 75% of the entire circumference of the blood vessel or which extends over the entire circumference of the blood vessel.

[0067] In one embodiment, the cover extends over at most 80%, in particular at most 60%, in particular at most 40% of the length of the grid structure, wherein the cover is spaced apart from the distal end and / or the proximal end of the grid structure. The length L corresponds to the total length of the covering device, in particular of the implant. By this incomplete covering of the cylindrical region of the grid structure, it is achieved that the possible blood vessels in the vicinity of the aneurysm and in particular in the vicinity of the opening of the aneurysm continue to be perfused, i.e. supplied with blood. This embodiment has likewise proven to be particularly suitable for aneurysms with adjacent side vessels and also for smaller aneurysms.

[0068] Since the proximal cells are open, the proximal spacing is particularly important for locking on the guide wire. For example, if the proximal edge cells are implemented as open, i.e. uncovered, the locking system of the applicant, the so-called "Crown-Sleeve" of the transport wire, can be safely coupled. For this, an upper limit of 80% coverage is sufficient. It should be sufficient to leave 10% of the total length L of open edge cells on each axial side.

[0069] In one embodiment, the cover has at least 10 holes over an area of 100000 pm2, the size of the holes being at least 15 pm2. 2 2 ​In the process of manufacturing the cover, the minimum size of the pores can be adjusted in particular by the process duration of the electrospinning. This combination of a certain minimum number of pores and the minimum size of these pores has proven particularly advantageous in practice for a sufficient blood permeability of the cover while having a good covering effect.

[0070] Preferably, the cover is formed from a plastic material, in particular a polymer, and preferably a polyurethane. This material is particularly light and can be easily made into filaments by the electrospinning method. Thus, the plastic material enables, on the one hand, the manufacture of a particularly thin and fine-pored cover. On the other hand, the plastic material itself already has a high flexibility, thus enabling a high compressibility of the medical kit. Alternatively, the cover can also be formed from a polyethylene, a fluoropolymer or a thermoplastic polyurethane based on, for example, polycarbonate. Furthermore, alternatively or additionally, it can be provided, for example, that a filler substance, such as an anti-thrombotic substance, is embedded in the above-mentioned materials used for the cover before the cover is formed from these materials by the electrospinning process. Alternatively or additionally, the cover is coated with such a substance, for example an anti-thrombotic substance. To this end, the surface of the cover is provided in particular with a nano-coating.

[0071] Preferably, the cover is formed from a plastic material, in particular a polymer, and preferably a polyurethane, preferably having a Shore hardness of at least 80 A, in particular at least 90 A, in particular at least 55 D, in particular at least 65 D, in particular at least 75 D. These material values have proven advantageous for the membrane function of the cover.

[0072] In a further embodiment, the cover is arranged on the outer side and / or on the inner side of the grid structure. The grid structure forms a support structure in the case where the cover is arranged on the outer side of the grid structure, which exerts a radial force sufficient to fix the cover against the vessel wall. In this regard, the grid structure supports the cover arranged on the outside.

[0073] Alternatively or additionally, the cover can be arranged on the inner side of the grid structure. In particular, the grid structure can be embedded between two covers, which are each formed from an electrospun fabric. In this regard, the grid elements of the grid structure can be completely covered by the electrospun fabric. In particular, it can be provided that the electrospun fabric of the cover on the inner side of the grid structure extends through the cells of the grid structure and is connected to the electrospun fabric of the cover on the outer side of the grid structure. Thus, the grid elements delimiting the cells are covered on all sides by the electrospun fabric.

[0074] According to one preferred design, the grid structure is formed by stegs which are connected to one another in one piece, i.e. integrally, and define closed, in particular diamond-shaped cells. Preferably, the grid structure has 3 to 9, in particular 4 to 6, successively arranged cells in the circumferential direction, which form a cell ring on the circumferential side.

[0075] The grid structure can thus in principle be configured as a one-piece grid structure. In this regard, it is provided in the preferred embodiment that the grid elements form stegs which are integrally coupled to one another by steg connections (one-piece grid structure).

[0076] The grid structure can also be formed by interwoven wires. The wire braid can consist of a single wire which is turned around and returned at the longitudinal ends of the mesh structure. The wire can interweave itself to form the mesh structure, or the mesh structure can consist of a plurality of wires which interweave one another. The plurality of wires can be turned around and returned at one axial longitudinal end, while the opposite axial longitudinal end can have open wire ends. The interwoven wires can also have open wire ends at both axial longitudinal ends.

[0077] The grid structure can thus comprise a braid which is braided from at least one wire, in particular a plurality of wires, and forms a mesh, wherein the wires are movable relative to one another at the intersection points.

[0078] The embolization medium can comprise at least one deformable wire, in particular a coil, and / or an embolization liquid. In particular, the embolization liquid is an embolization liquid which can be delivered through a microcatheter with a maximum outer diameter of 2 Fr (maximum inner diameter of 0.017" / 0.43 mm).

[0079] The wire can have a radiopaque core material and a sheath material made of a shape memory alloy. In particular, it is provided that the volume ratio between the core material, which is preferably platinum, and the volume of the entire composite wire is between 20% and 40%, in particular between 25% and 35%. The braided grid structure is characterized by a particularly high flexibility, in particular bending flexibility, while the one-piece grid structure has a relatively thin wall thickness, so that the grid structure has a low influence on the blood flow in the blood vessel. Furthermore, the thickness of the stegs is preferably in the range between 30 pm and 60 pm. Furthermore, the cells are each defined by a total of four stegs, wherein in the preferred design the basic geometry of the cells is substantially diamond-shaped. In particular, each cell is defined by two pairs of stegs, wherein the stegs which are substantially parallel to one another or opposite one another and are not directly connected to one another form a steg pair. This design has already been described in the patent document DE 10 2011 009 371 B3 of the applicant, which is incorporated by reference. Figure 1The neutralization is described in paragraphs

[0041] to

[0046] and can be referred to in this respect. The tabs of the first pair of tabs have a smaller tab width than the tabs of the second pair of tabs. This arrangement of tabs with different tab widths increases the flexibility of the mesh structure, thereby facilitating the introduction of the medical kit into the human blood vessels, in particular when the vessel curvature of these blood vessels is large. The increased flexibility improves the adhesion to the vessel wall, thereby preventing the formation of hyperemic areas which promote thrombus formation. Good flexibility and the resulting good introducibility in and / or through the catheter are particularly important in combination with a biological coating, preferably a fibrin, preferably a fibrin comprising heparin.

[0080] In addition to the pores formed by electrospinning, the fabric can be at least locally perforated by further pores which are structured in the electrospun fabric by a processing of the fabric, in particular by laser cutting or by thermal expansion with the aid of a laser. In this way, after the electrospinning process, it is possible to increase the porosity or to enlarge the pores in a targeted manner and, if desired, locally. For example, defined pores which are laser cut or which are thermally expanded with a laser beam can be structured over the entire circumference or only over a part of the circumference.

[0081] Preferably, the fabric is perforated by further pores over at least 25%, in particular at least 40%, in particular at least 50% of the circumference of the mesh structure. Thus, for example, the region opposite the aneurysm neck can be perforated in a targeted manner.

[0082] The fabric can be free of further pores over at least 25%, in particular at least 40%, in particular at least 50% of the circumference of the mesh structure. In other words, a part of the fabric is not post-processed or subsequently perforated. In this part of the fabric, in addition to the pores formed by electrospinning, no other pores are introduced into the fabric. This range of fabrics comprises pores formed only by electrospinning. The region of the fabric which is free of further pores can be arranged in the region of the aneurysm neck in the implanted state. This can be desirable, for example, when the unaltered porosity of the electrospun fabric is advantageous for the treatment of an aneurysm.

[0083] A combined region consisting of an unaltered electrospun fabric and a subsequently perforated electrospun fabric is possible.

[0084] The further pores can be structured in both axial directions starting from the axial center of the mesh structure. In a further embodiment, the additional pores can be arranged proximally or distally within the covering or the fabric.

[0085] The further pores can be distributed over a length corresponding to at least 25% of the axial length of the covering or the fabric, in particular at least 30%, in particular at least 40%, in particular at least 50% of the axial length of the covering or the fabric.

[0086] To facilitate perfusion, the additional holes can have a size of at least 50 pm, in particular at least 100 pm, in particular at least 200 pm, in particular at least 300 pm.

[0087] For the subsequently added enlarged hole geometry, it is generally supplemented that the additional hole can be circular or elliptical in shape. The additional hole can also have no identifiable shape pattern.

[0088] The spacing of the additional holes to each other can be at least 1 times the diameter of the additional hole, in particular at least 1.5 times the diameter, in particular at least 2 times the diameter, in particular at least 2.5 times the diameter. Thus, 1 times the spacing means the diameter of the other hole.

[0089] In a particularly preferred embodiment, the circumferential contour of the cover is at least partially, in particular over the entire circumference, marked by a radiopaque medium. This can be achieved, for example, by radiopaque wire that is woven into the mesh structure along the contour of the cover. It is also possible to achieve the contour of the cover by arranging radiopaque sleeves (e.g. Pt-IR sleeves or crimped C-sleeves).

[0090] Thus, the position of the cover or the fabric is visible under radiological exposure. The physician can therefore place the device safely, also in the correct rotational position.

[0091] The fabric itself can have a radiopaque medium. For example, the filaments of the fabric can be filled with a radiopaque material, in particular with at least 10% to at most 25% of a radiopaque material (e.g. barium sulfate BaS04). The basic color of the filaments of the fabric can be transparent, which can assume a white / yellowish color when barium sulfate BaS04 is added.

[0092] A collateral aspect of the present invention relates to a medical system for treating an aneurysm, having a medical kit. The kit is the medical kit already described above. The system further comprises a delivery device, in particular a microcatheter, with which the cover can be perforated for the introduction of embolization medium.

[0093] Advantageously, the cells of the mesh structure have an inner diameter in the expanded state that corresponds to at least the outer diameter of the delivery device or can be expanded to at least the outer diameter of the delivery device. The inner diameter is the diameter of the largest possible circle that can be inscribed in the hole. In other words, the inner diameter of the hole corresponds to the outer diameter of a cylinder that can just still be pushed through the hole. If the delivery device, in particular the catheter, is not aligned at an angle of 90° to the hole of the cover or the cell of the mesh structure during application, an oval opening that occupies more area results.

[0094] Thereby, especially in the above-mentioned embodiments of the medical system, it is ensured that the delivery device can be easily guided through the covering or the fabric into the aneurysm.

[0095] Preferably, the embolization medium is formed by a deformable wire, especially a coil wire, especially a coil as already mentioned above, or by a liquid, for example a hydrogel. This configuration of the embolization medium has proven to be particularly suitable for the treatment of aneurysms.

[0096] The advantages and preferred design solutions listed in connection with the medical kit can be transferred analogously to the medical system and vice versa. Unless stated otherwise, all dimensional data relating to the medical kit and the medical system apply to any extended state of the grid structure. BRIEF DESCRIPTION OF DRAWINGS

[0097] Further details of the application are explained in greater detail with reference to the accompanying drawings and on the basis of embodiments.

[0098] Herein, Figures 1 to 8 A use of the medical kit according to an embodiment of the application is shown, wherein the embolization medium is a coil. Figures 9 to 16 Another use scenario of the medical kit according to an embodiment of the application is shown, wherein the embolization medium is an embolic agent.

[0099] In particular, in the drawings:

[0100] Figure 1 A side view of the covering device according to the medical kit according to the application according to the first embodiment in the implanted state is shown (step 1);

[0101] Figure 2 A side view of the covering device according to Figure 1 with the delivery device and the guide wire penetrating the covering of the covering device is shown (step 2);

[0102] Figure 3 A side view of the covering device according to Figure 1 with the delivery device penetrating the covering is shown (step 3);

[0103] Figure 4 A side view of the covering device according to Figure 1 with the guide wire being withdrawn is shown (step 4);

[0104] Figure 5 A side view of the covering device according to Figure 1 with the coil wire being advanced by the delivery device is shown (step 5);

[0105] Figure 6 A side view of the covering device according to Figure 1a side view of the covering device according to the first embodiment, wherein the coil wire is introduced into the aneurysm (step 6);

[0106] Figure 7 a side view of the covering device according to the first embodiment in the final state, wherein the covering blocks the coil wire arranged in the aneurysm and the opening left after removal of the delivery device is greatly reduced (step 8); Figure 1 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7);

[0107] Figure 8 a side view of the covering device according to the first embodiment in the final state, wherein the covering blocks the coil wire arranged in the aneurysm and the opening left after removal of the delivery device is greatly reduced (step 8); Figure 1 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7);

[0108] Figure 9 a side view of the covering device according to the first embodiment in the final state, wherein the covering blocks the coil wire arranged in the aneurysm and the opening left after removal of the delivery device is greatly reduced (step 8);

[0109] Figure 10 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7); Figure 9 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7);

[0110] Figure 11 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7); Figure 9 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7);

[0111] Figure 12 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7); Figure 9 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7);

[0112] Figure 13 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7); Figure 9 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7);

[0113] Figure 14 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7); Figure 9 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7);

[0114] Figure 15 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7); Figure 9 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7);

[0115] Figure 16 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7); Figure 9 a side view of the covering device according to the first embodiment, wherein the delivery device is removed from the blood vessel and the opening left after removal of the delivery device is greatly reduced (step 7);

[0116] Figure 17 A side view of the covering device of the medical kit according to the application in the implanted state is shown according to a further embodiment, and

[0117] Figure 18 A side view of the covering device of the medical kit according to the application in the implanted state is shown according to a further embodiment.

[0118] In the drawings, identical actions of components are denoted by identical reference numerals. DETAILED DESCRIPTION

[0119] The medical kit 2 is shown schematically in Figures 1 to 8 for treating an aneurysm 4 or generally a vascular malformation (e.g. a fistula) and in Figure 1 in a state arranged within a blood vessel 6.

[0120] The medical kit 2 has a covering device 12 which is movable through a not shown catheter to the treatment site 10. Preferably, the treatment site 10 is the site along the blood vessel 6 where the aneurysm 4 is formed. The covering device 12 is for permanently covering the aneurysm 4. This means that the covering device 12 cannot be withdrawn again into the catheter after complete release from the catheter, but is permanently left in the blood vessel. In particular, the covering device 12 is a permanent implant, in particular the covering device 12 is a stent.

[0121] Temporary covering devices which are removed again from the blood vessel after the treatment have to be distinguished from permanent covering devices. A further distinguishing feature of the permanent covering device is the detachable connection to the transport wire which is necessary in order to decouple the covering device or the mesh structure from the delivery system after complete release from the delivery device. This is not the case with temporary covering devices which are fixedly connected to the transport wire in order to be pulled back into the delivery device.

[0122] The covering device 12 comprises a self-expandable mesh structure 14. To this end, the mesh structure 14 is preferably made of a shape memory material. The mesh structure 14 is tubular or hollow-cylindrical and is open at a proximal longitudinal end 16 and at a distal longitudinal end 18. This means that the mesh structure 14 has a flow cross section without mesh structure 14 at both longitudinal ends 16, 18. The flow cross section is a flowable cross section transverse to the longitudinal axis of the mesh structure 14, which is defined radially externally by the blood vessel or the mesh structure 14. This is the difference to a covering device or mesh structure 14 which is permanently implantable, in which the mesh structure at least at the proximal longitudinal end tapers funnel-shaped into the flow cross section. In contrast, in the permanently implantable covering device 12, the mesh structure 14 lies against the blood vessel wall along the entire length and exerts a radial force on the blood vessel wall.

[0123] Furthermore, the mesh structure 14 is at least partially provided with a covering 20. The covering 20 is made of an electrospun fabric and forms a porous membrane. The electrospun fabric is suitable for endowing the covering with a membrane function. The porous membrane is configured such that it can be penetrated by a delivery device for the embolization medium. Furthermore, the membrane is suitable for lying against the outer circumference of the delivery device in the state in which the membrane is penetrated.

[0124] This applies to all coverings 20 in the present application.

[0125] Various possibilities exist for the shape of the covering 20.

[0126] For example, as shown in Figures 1 to 16 , the covering 20 can extend along a partial length of the mesh structure 14, or over a part of the total length L of the mesh structure 14, in particular over a maximum of 80%, in particular over a maximum of 60% and especially particularly over a maximum of 40%. The total length L of the mesh structure is shown in the figures and extends along the center line of the mesh structure between the outermost axial longitudinal ends.

[0127] It is thereby achieved that the covering 20 in the implanted state is located only in the region of the opening 28 of the aneurysm 4, so that cells and / or side vessels adjoining the aneurysm 4 are not covered by the covering 20. Thus, due to the mesh structure 14 configured with cells, the cells and / or side vessels can be continued to be supplied with blood and thus with nutrients.

[0128] As can be clearly seen in the figures, the covering 20 is arranged substantially centrally, i.e. the covering 20 is arranged in the range of the axial center of the mesh structure 14. In other words, the axial longitudinal ends of the covering 20 are at approximately the same distance or spacing from the proximal and distal longitudinal ends 16, 18 of the mesh structure 14.

[0129] The profile of the longitudinal end portions of the cover 20, which extend in the circumferential direction of the mesh structure 14, essentially corresponds to the profile of the proximal and distal longitudinal end portions 16, 18 of the mesh structure. This feature is disclosed and claimed in connection with the specific embodiments and generally in connection with other embodiments not shown here.

[0130] In the cover 20 shown in the drawing, the cover extends over the entire circumference of the mesh structure 14. As shown in Figure 17 , Figure 18 , the cover 20 can also only cover a partial section, i.e. a corner section, of the mesh structure 14 in the circumferential direction.

[0131] Here, in particular in the case where the embolization medium 40 is placed in the aneurysm 4, the cover 20 serves to make the embolization medium 40, after placement, unable to escape from the aneurysm 4 until the blood in the aneurysm 4 is coagulated by the embolization medium 40 and thus the aneurysm 4 is reliably closed.

[0132] Based on Figures 1 to 8 , it is set forth how a respective embodiment of a medical kit comprising the covering device 12 and the embolization medium 40 is used for treating an aneurysm. Correspondingly, the treatment of other vascular malformations is possible.

[0133] In Figure 1 , the covering device 12 is shown, for example, in the form of a stent in a permanently implanted state, i.e. after complete release from the delivery system (step 1). The covering device 12 is arranged together with the cover 20 above the aneurysm opening 28. The cover 20 covers the aneurysm opening 28. The radiopaque markers 56 on both axial longitudinal end portions 16, 18 mark the position of the covering device 12.

[0134] As can be seen in Figure 2 , in step 2, a delivery device 44 in the form of a microcatheter is introduced through the lumen of the covering device 12. For this purpose, in a known manner, a guide wire 22 is also arranged in the lumen of the covering device 12, through which the delivery device 44 is guided to the treatment site. As can be clearly seen in Figure 2 , the guide wire 22 penetrates the cover 20 in the region of the aneurysm opening 28. Here, the membrane function of the cover 20 comes into play. Due to the pores formed by the electrospun fabric, the pores of the cover can be perforated or enlarged or dilated by the guide wire 22. The guide wire 22 penetrates the material of the cover 20, wherein the respective pores penetrated by the guide wire 22 are dilated. Thereby, an opening 24 is formed through which the guide wire 22 is pushed into the interior of the aneurysm 4.

[0135] In Figure 3The image shows the delivery device 44 being further pushed forward into the aneurysm 4 via the guide wire 22. In this state, the delivery device 44, specifically the free end of the distal end of the delivery device 44, extends into the aneurysm 4. Here, the delivery device 44 penetrates the covering 20 in the region of the opening 24 already formed by the guide wire 22. The opening 24 is further expanded by the delivery device 44 to the outer diameter of the delivery device 44. The expanded opening 24 fits tightly against the outer contour of the delivery device 44 and thus seals the aneurysm 4 relative to the lumen of the covering device 12.

[0136] This is achieved through the membrane-like structure of the covering 20, specifically through an electrospun fabric that is elastic enough to allow the material around the pierced hole or opening 24 to deform elastically.

[0137] according to Figure 4 In step 4, the guide wire is withdrawn from the delivery device 44 such that the free end of the delivery device 44 is placed in the aneurysm 4 and has a free cavity for applying the embolization medium 40.

[0138] exist Figure 5 As shown, in step 5, the embolization medium 40, specifically the coil wire 42, is delivered to the aneurysm through the delivery device 44 and the opening 24 in the cover 20.

[0139] In step 6, as in Figure 6 As shown, the aneurysm 4 is filled with embolization medium 40 or coil wire 42. Even in this state, the cover 20 prevents the embolization medium 40 from entering the aneurysm. Furthermore, the cover 20 seals the aneurysm 4 relative to the lumen of the covering device 12 in the area of ​​the opening 24, because the opening 24 is tightly fitted against the outer diameter of the delivery device 44. Thus, leakage of the embolization medium 40 is prevented during application.

[0140] As in Figure 7 As shown in step 7, after the aneurysm has been adequately filled with the embolization medium 40, the delivery device 44 is removed from the lumen of the covering device 12. Figure 7 As can be clearly seen, the opening 24 retracts. The retracted opening 24 has a diameter smaller than the outer diameter of the delivery device 44. Thus, the embolization medium 40 is safely retained in the aneurysm 4. It is not absolutely necessary for the opening 24 to completely retract and restore its initial orifice size. It is sufficient for the opening 24 to retract to the extent that the embolization medium 40 cannot reach the lumen of the covering device 12 through the retracted opening 24. The coil / hydrogel delivered by the delivery device, or the commonly delivered embolization medium, roughly corresponds to the inner diameter of the delivery device. When the opening becomes smaller after the delivery device is removed, neither the embolization medium (i.e., the coil and hydrogel) can escape through the opening.

[0141] Figure 8 The final state after the complete removal of the delivery device 44 and the covering device 12 holds the embolization medium 40 in the aneurysm 4 is shown.

[0142] Steps 1 to 8 can be performed in the same operation, i.e. directly one after the other and consecutively in time. It is also possible to initially implant only the covering device without first performing steps 2 to 8. If it turns out that the treatment is not successful enough, the aneurysm can then be treated without doubt with the embolization medium 40. This means that steps 2 to 8 will be performed in a second, later operation. Thus, the medical kit comprising the covering device and the embolization medium enables a flexible and targeted treatment method for the aneurysm. Figure 1 Another embodiment is shown in

[0143] The embodiment differs from the embodiment according to Figures 9 to 16 in that instead of the coil wire 42, another embolization medium 40 is used, namely an embolization liquid 46. The embolization liquid 46 is applied in the same way as the coil wire 42. In this respect, reference is made to the explanations regarding Figures 1 to 8 Figures 1 to 8 In this embodiment, the opening 24 is resettable such that after the removal of the delivery device 44 a sufficiently small opening remains in the covering 20 through which the embolization liquid 46 cannot overflow. It also applies here that the opening 24 does not have to be completely closed in order to achieve the desired purpose.

[0144] In this embodiment, the opening 24 is resettable such that after the removal of the delivery device 44 a sufficiently small opening remains in the covering 20 through which the embolization liquid 46 cannot overflow. It also applies here that the opening 24 does not have to be completely closed in order to achieve the desired purpose.

[0145] Figure 17 A mesh structure 14 according to an embodiment of the application in the implanted state is shown, in which the covering 20 is arranged on the mesh structure 14 in the region of the aneurysm neck and covers the aneurysm neck. The covering 20 is arranged on a partial circumference or on an angular section of the mesh structure 14. In this embodiment, the fabric or the covering 20 covers approximately half the circumference of the mesh structure 14 or stent. Different degrees of coverage, i.e. more or less than half the circumference of the mesh structure 14, are possible.

[0146] Thereby, the supply of cells and / or collateral vessels adjacent to the aneurysm 4 is further optimized, since thereby preferably only the opening 28 of the aneurysm 4 is covered and further supply of blood and nutrients for cells and / or collateral vessels located on the same level as the aneurysm 4 is possible. Thus, for example, collateral vessels opposite the aneurysm 4 can be supplied with blood.

[0147] As can be seen in Figure 17 Figure 18 ​​Unlike, in addition to the pores constructed by electrospinning, no other pores are provided in the fabric. The properties of the fabric are thus determined exclusively by the pores constructed by electrospinning in the manufacturing process.

[0148] Figure 18 A further embodiment of the application is shown in which, as in Figure 17 , the mesh structure 14 is implanted for the treatment of an aneurysm. Unlike Figure 17 , the covering 20, in particular the fabric, is applied to the mesh structure 14 over the entire circumference, more precisely by electrospinning. A portion of the covering 20, in particular the portion of the covering 20 opposite the aneurysm neck, is additionally perforated in addition to the pores 52 constructed during electrospinning. This is achieved by a post-processing of the fabric, for example by laser cutting or by thermal expansion with the aid of a laser. As can be seen in Figure 18 , the further pores 54 thus formed in the fabric are larger than the pores 52 formed by electrospinning. In the example according to Figure 18 , each cell is constructed with four further pores 54. The number of these further pores 54 can vary. Unlike the pores 52 formed by electrospinning, these further pores 54 are defined in terms of geometry, for example as circular. This is achieved by laser cutting or by thermal expansion or thermal melting with the aid of a laser.

[0149] Here, the further perforation of the fabric enables targeted influencing of the permeability of the fabric, for example in order to improve the blood supply in the side branches without impairing the treatment of the aneurysm.

[0150] As can be clearly seen in Figure 17 , Figure 18 , in the medical kit 2 and in particular in the mesh structure 14, radio markers 56 are provided. The radio markers 56 are arranged at the cell tips of the edge-side cells of the mesh structure 14. In particular, the radio markers 56 can be formed as radio-opaque sleeves, for example made of platinum or gold, which are crimped at the cell tips of the edge-side cells. It can be seen in Figure 17 , Figure 18 that three radio markers 56 are arranged at each longitudinal end of the mesh structure 14, respectively.

[0151] According to Figure 17 and Figure 18 , the covering device 12 is combined with the embolization medium 40 into a medical kit. This kit can in turn be combined with the delivery device 44 into a system.

[0152] The above-described embodiments, in particular with respect to the extension of the cover 20 along the length L of the mesh structure 14 and with respect to the extension of the cover 20 along the circumferential direction of the mesh structure 14, can be designed and combined in any combination. Thus, for example, a design is also possible in which the cover 20 extends over the entire length L of the mesh structure, however, in addition, only over a partial circumferential direction of the mesh structure 14.

[0153] List of reference signs

[0154] 2 medical kit

[0155] 4 aneurysm

[0156] 6 blood vessel

[0157] 8 none

[0158] 10 treatment site

[0159] 12 covering device

[0160] 14 mesh structure

[0161] 16 proximal longitudinal end

[0162] 18 distal longitudinal end

[0163] 20 cover

[0164] 22 guide wire

[0165] 24 opening

[0166] 26 none

[0167] 27 circumferential face

[0168] 28 opening of the aneurysm

[0169] 30 none

[0170] 32 none

[0171] 34 tab

[0172] 36 unit

[0173] 40 embolization medium

[0174] 42 coil wire

[0175] 44 delivery device

[0176] 46 embolization liquid

[0177] 48 none

[0178] 50 none

[0179] 52 hole

[0180] 54 additional hole

[0181] 56 radiographic marker

[0182] L length.

Claims

1. A medical kit for treating vascular malformations, comprising: A permanently implantable covering device (12) for covering vascular malformations, wherein the covering device (12) has a tubular, self-expanding mesh structure (14) and a cover (20) made of electrospun fabric, wherein the cover (20) is connected to and at least partially covers the mesh structure (14) so ​​as to be placed over the vascular malformation in the implanted state; and Embolization medium (40), which can be applied in the implanted state via delivery device (44) for the treatment of vascular malformations, The mesh structure (14) has units (36) or meshes, and in the extended state, the units or meshes have an inner diameter (D) that corresponds at least to the outer diameter (A) of the conveying device or can be expanded to an inner diameter (D) that corresponds at least to the outer diameter (A) of the conveying device. The covering (20) forms a porous membrane that can be penetrated by the delivery device (44) to apply the embolizing medium (40), and is adapted to adhere to the outer periphery of the delivery device (44) in the penetrated state. The porous membrane of the cover (20) is adapted to retract at least partially the opening (24) formed when the conveying device penetrates the membrane after the conveying device is removed. The conveying device has a distal outer diameter of 0.7 mm, or the outer diameter of the conveying device is at most 2 Fr.

2. The medical kit according to claim 1, characterized in that, The vascular malformation is an aneurysm and / or fistula.

3. The medical kit according to claim 1, characterized in that, The covering device is a bracket.

4. The medical kit according to any one of claims 1-3, characterized in that, The porous membrane of the cover (20) is adapted to reduce the opening (24) to a maximum of 80% of the diameter of the conveying device.

5. The medical kit according to any one of claims 1-3, characterized in that, The cover (20) is slightly porous, so that it blocks the applied embolic medium when implanted.

6. The medical kit according to any one of claims 1-3, characterized in that, The porosity of the covering (20) is up to 70%.

7. The medical kit according to any one of claims 1-3, characterized in that, The porosity of the covering (20) is at least 5%.

8. The medical kit according to any one of claims 1-3, characterized in that, The covering (20) extends over the entire circumference of the grid structure (14).

9. The medical kit according to any one of claims 1-3, characterized in that, The covering (20) extends over a maximum of 70% of the circumference of the grid structure (14).

10. The medical kit according to any one of claims 1-3, characterized in that, The cover (20) extends over a maximum of 80% of the length (L) of the mesh structure (14), wherein the cover (20) is spaced apart from the distal end (18) and / or proximal end of the mesh structure (14).

11. The medical kit according to any one of claims 1-3, characterized in that, The covering (20) is 100,000 µm 2 The area has at least 10 holes (52), the size of which is at least 15µm. 2 .

12. The medical kit according to any one of claims 1-3, characterized in that, The electrospun fabric of the covering (20) has a maximum yarn thickness of 2µm and a minimum of 0.3µm.

13. The medical kit according to any one of claims 1-3, characterized in that, The covering (20) is made of plastic material.

14. The medical kit according to claim 13, characterized in that, The covering (20) is formed of a polymer.

15. The medical kit according to claim 14, characterized in that, The covering (20) is formed of polyurethane.

16. The medical kit according to claim 13, characterized in that, The Shore hardness of the plastic material is at least 80A.

17. The medical kit according to claim 13, characterized in that, The plastic material has a Shore hardness of at least 55D.

18. The medical kit according to any one of claims 1-3, 14-17, characterized in that, The cover (20) is arranged on the outer and / or inner sides of the grid structure (14).

19. The medical kit according to any one of claims 1-3, 14-17, characterized in that, The grid structure (14) is formed by tabs (34) that are connected one piece to each other and define closed units (36).

20. The medical kit according to claim 19, characterized in that, The tab defines a rhomboid unit.

21. The medical kit according to any one of claims 1-3, 14-17, characterized in that, The mesh structure (14) includes a braid made of at least one thread to form a mesh, wherein the threads are movable relative to each other at intersections.

22. The medical kit according to any one of claims 1-3, 14-17, and 20, characterized in that, The embolization medium (40) includes at least one deformable wire (42) and / or embolization fluid.

23. The medical kit according to claim 22, characterized in that, The deformable wire is a coil.

24. The medical kit according to any one of claims 1-3, 14-17, 20, and 23, characterized in that, In addition to the holes (52) formed by electrospinning, the fabric is at least partially perforated by additional holes (54) which are formed in the electrospinned fabric through processing of the fabric.

25. The medical kit according to claim 24, characterized in that, The processing is laser cutting or thermal expansion using a laser.

26. The medical kit according to claim 24, characterized in that, The fabric is perforated by the additional holes at least 25% of the circumferential direction of the mesh structure (14).

27. The medical kit according to claim 24, characterized in that, The fabric has no additional holes in at least 25% of the circumferential direction of the mesh structure (14).

28. The medical kit according to claim 24, characterized in that, The additional holes are formed in two axial directions, starting from the axial center of the mesh structure (14).

29. The medical kit according to claim 24, characterized in that, The size of the additional hole is at least 50µm.

30. The medical kit according to claim 24, characterized in that, The spacing between the additional holes is at least one time the diameter of the additional holes.

31. The medical kit according to any one of claims 1-3, 14-17, 20, 23, 25-30, characterized in that, The circumferential outline of the covering (20) is marked at least partially by a ray-impermeable medium.

32. The medical kit according to any one of claims 1-3, 14-17, 20, 23, 25-30, characterized in that, The fabric itself has a medium through which rays cannot pass.

33. A medical system for treating vascular malformations, comprising a delivery device and a medical kit according to any one of claims 1-32, wherein the delivery device is capable of penetrating the covering (20) to introduce the embolic medium.

34. A permanently implantable covering device (12) for treating vascular malformations, the covering device (12) having a tubular, self-expanding mesh structure (14) and a cover (20) made of electrospun fabric, wherein the cover (20) is connected to and at least partially covers the mesh structure (14) for placement over the vascular malformation in an implanted state, wherein the cover (20) forms a porous membrane permeable by a delivery device (44) to apply an embolic medium (40), and is adapted to abut against the periphery of the delivery device (44) in a permeated state, wherein the porous membrane of the cover (20) is adapted to retract the opening (24) formed when the membrane is permeated by the delivery device by up to 80% of the diameter of the delivery device after removal of the delivery device, and wherein the cover (20) is at 100,000 µm 2 The area has at least 10 holes (52), the size of which is at least 15µm. 2 , in, The mesh structure (14) has units (36) or meshes, which, in an expanded state, have an inner diameter (D) at least corresponding to the outer diameter (A) of the conveying device or can be expanded to an inner diameter (D) at least corresponding to the outer diameter (A) of the conveying device, and wherein the conveying device has a distal outer diameter of 0.7 mm or the outer diameter of the conveying device is at most 2Fr.

35. The covering device according to claim 34, characterized in that, The covering device is a bracket.

36. The covering device according to claim 34, characterized in that, The vascular malformation is an aneurysm and / or fistula.

Images