MEDICAL KIT, MEDICAL SYSTEM, AND COVERING DEVICE FOR THE TREATMENT OF ANEURYSMS

Abstract

The disclosure relates to a medical kit for the treatment of vascular malformations, in particular aneurysms and/or fistulas, having a permanently implantable covering device, in particular a stent, for covering the vascular malformation, the covering device having a tubular, self-expandable lattice structure and a covering made of an electrospun fabric, the covering being connected to the lattice structure and overlapping the lattice structure at least in part such that, when implanted, the covering is placed over the vascular malformation; and an embolisation means, which can be applied by a feed means in the implanted state for treatment of the vascular malformation, the covering forming a porous membrane which can be penetrated by the feed means for application of the embolisation means and which is designed to lie against the outer periphery of the feed means in the penetrated state.

Claims

1.-27. (canceled)

28. A medical kit for treatment of a vascular malformation comprising: a permanently implantable covering device covering the vascular malformation, wherein the covering device has a tubular self-expandable mesh structure and a covering produced from an electrospun fabric, wherein the covering is connected to the mesh structure and at least partially covers the mesh structure in order to be placed over the vascular malformation in an implanted state; and an embolisation means which, in the implanted state, is configured to be applied by means of a delivery means for the treatment of the vascular malformation, wherein the covering forms a porous membrane adapted to be penetrated by the delivery means for application of the embolisation means and is adapted to lie against an outer circumference of the delivery means when in a penetrated state.

29. The medical kit according to claim 28, wherein the porous membrane of the covering is adapted to at least partially contract an opening formed by the delivery means when the porous membrane is penetrated following removal of the delivery means.

30. The medical kit according to claim 29, wherein the porous membrane of the covering is adapted to contract the opening by at most 80% of a diameter of the delivery means.

31. The medical kit according to claim 28, wherein the covering is slightly porous in a manner such that in the implanted state, the covering retains the applied embolisation means.

32. The medical kit according to claim 31, wherein the covering has a porosity of at most 70%.

33. The medical kit according to claim 31, wherein the covering has a porosity of at least 5%.

34. The medical kit according to claim 28, wherein the covering extends over at most 70% of a circumference of the mesh structure.

35. The medical kit according to claim 28, wherein the covering extends over an entire circumference of the mesh structure.

36. The medical kit according to claim 28, wherein the covering has at least 10 pores with a size of at least 15 μm.sup.2 over an area of 100000 μm.sup.2.

37. The medical kit according to claim 28, wherein the mesh structure is formed from webs connected together in one piece and delimited in closed diamond-shaped cells.

38. The medical kit according to claim 28, wherein the expandable mesh structure includes a braid formed from one or more wires that are movable relative to each other at points of intersection.

39. The medical kit according to claim 28, wherein the embolisation means comprises at least one deformable wire.

40. A medical kit for treatment of a vascular malformation comprising: a permanently implantable covering device covering the vascular malformation, wherein the covering device has a tubular self-expandable mesh structure and a covering produced from an electrospun fabric, wherein the covering is connected to the mesh structure and at least partially covers the mesh structure in order to be placed over the vascular malformation in an implanted state, wherein the covering includes an electrospun fabric having pores formed by electrospinning, wherein the fabric is perforated, at least in regions, by further pores formed by laser cutting or thermal widening using a laser; and an embolisation means which, in the implanted state, is configured to be applied by means of a delivery means for the treatment of the vascular malformation, wherein the covering forms a porous membrane adapted to be penetrated by the delivery means for application of the embolisation means and is adapted to lie against an outer circumference of the delivery means when in a penetrated state.

41. The medical kit according to claim 40, wherein the pores cover at least 25% of the circumference of the expandable mesh structure.

42. The medical kit according to claim 40, wherein the further pores are formed in both axial directions outwards from an axial centre of the expandable mesh structure.

43. The medical kit according to claim 40, wherein a size of the further pores is at least 50 μm.

44. The medical kit according to claim 40, wherein separations of the further pores with respect to each other in regards to a diameter of the further pores is at least one times distance.

45. The medical kit according to claim 40, wherein a circumferential contour of the covering is marked by a radiopaque means, at least in sections.

46. The medical kit according to claim 40, wherein the fabric has a radiopaque means.

47. A permanently implantable stent for treatment of a vascular malformation comprising: a covering device having a tubular self-expandable mesh structure and a covering produced from an electrospun fabric, wherein the covering is connected to the mesh structure and at least partially covers the mesh structure in order to be placed over the vascular malformation in an implanted state, wherein the covering forms a porous membrane adapted to be penetrated by a delivery means for application of an embolisation means and is adapted to lie against an outer circumference of the delivery means when in a penetrated state, wherein the porous membrane of the covering is adapted such that an opening formed by the delivery means upon penetration of the membrane contracts by at most 80% of a diameter of the delivery means after removal of the delivery means, and wherein the covering comprises at least 10 pores which have a size of at least 15 μm2 over an area of 100000 μm2.

Description

[0100] Specifically, in the figures:

[0101] FIG. 1 shows a side view of a covering device of a medical set in accordance with the invention according to a first embodiment in the implanted state (step 1);

[0102] FIG. 2 shows a side view of the covering device according to FIG. 1 with a delivery means and a guidewire which penetrates the covering of the covering device (step 2);

[0103] FIG. 3 shows a side view of the covering device according to FIG. 1, wherein the delivery means penetrates the covering (step 3);

[0104] FIG. 4 shows a side view of the covering device according to FIG. 1, wherein the guidewire has been contracted (step 4);

[0105] FIG. 5 shows a side view of the covering device according to FIG. 1, wherein a coil wire has been pushed through the delivery means (step 5);

[0106] FIG. 6 shows a side view of the covering device according to FIG. 1, wherein the coil wire has been introduced into the aneurysm (step 6);

[0107] FIG. 7 shows a side view of the covering device according to FIG. 1, wherein the delivery means has been removed from the vessel and the remaining opening has been made substantially smaller after removal of the delivery means (step 7);

[0108] FIG. 8 shows a side view of the covering device according to FIG. 1 in the final state, wherein the covering retains the coil wire disposed in the aneurysm and the remaining opening has been made substantially smaller after removal of the delivery means (step 8);

[0109] FIG. 9 shows a side view of a covering device of a medical set in accordance with the invention according to a second embodiment in the implanted state (step 1);

[0110] FIG. 10 shows a side view of the covering device according to FIG. 9 with a delivery means and a guidewire which penetrates the covering of the covering device (step 2);

[0111] FIG. 11 shows a side view of the covering device according to FIG. 9, wherein the delivery means penetrates the covering (step 3);

[0112] FIG. 12 shows a side view of the covering device according to FIG. 9, wherein the guidewire has been contracted (step 4);

[0113] FIG. 13 shows a side view of the covering device according to FIG. 9, wherein an liquid embolic has been transported through the delivery means (step 5);

[0114] FIG. 14 shows a side view of the covering device according to FIG. 9, wherein the liquid embolic has been introduced into the aneurysm (step 6);

[0115] FIG. 15 shows a side view of the covering device according to FIG. 9, wherein the delivery means has been removed from the vessel and the remaining opening has been made substantially smaller after removal of the delivery means (step 7);

[0116] FIG. 16 shows a side view of the covering device according to FIG. 9 in the final state, wherein the covering retains the liquid embolic disposed in the aneurysm and the remaining opening has been made substantially smaller after removal of the delivery means (step 8);

[0117] FIG. 17 shows a side view of a covering device of a medical set in accordance with the invention according to a further embodiment, in the implanted state, and

[0118] FIG. 18 shows a side view of a covering device of a medical set in accordance with the invention according to a further embodiment, in the implanted state.

[0119] In the figures, identical parts are shown with identical reference numerals.

[0120] The medical set 2 which is shown diagrammatically in FIGS. 1 to 8 serves for the treatment of aneurysms 4, or in general of vascular malformations such as fistulas, for example, and is shown in FIG. 1 in a state in which it is disposed in a vessel 6.

[0121] The medical set 2 has a covering device 12 which can be moved through a catheter (not shown) to a treatment site 10. The treatment site 10 is preferably a site along the vessel 6 at which the aneurysm 4 is formed. The covering device 12 serves to permanently cover the aneurysm 4. This means that the covering device 12, after it has been completely released from the catheter, can no longer be withdrawn into it but remains permanently in the vessel. Specifically, the covering device 12 is a permanent implant, in particular a stent.

[0122] Permanent covering devices are distinguished from temporary covering devices which are removed from the vessel again following treatment. A further distinguishing feature of the permanent covering device is the releasable connection to the transport wire, which is necessary in order to be able to uncouple the covering device or mesh structure from the delivery system after the delivery means has completely left the delivery means. This is not the case with temporary covering devices, which are securely connected to the transport wire in order to be contracted into the delivery means.

[0123] The covering device 12 comprises a self-expandable mesh structure 14. To this end, the mesh structure 14 is preferably produced from a shape memory material. The mesh structure 14 is tubular in shape or in the shape of a hollow cylinder and is open at the proximal longitudinal end 16 and at the distal longitudinal end 18. This means that at both longitudinal ends 16, 18, the mesh structure 14 has a cross section of flow which is free from the mesh structure 14. The cross section of flow is the cross section through which a flow can pass which is transverse to the longitudinal axis of the mesh structure 14 which is delimited radially outwardly by the vessel or by the mesh structure 14. This distinguishes permanently implantable covering devices or the mesh structure 14 from the mesh structure 14 of a temporarily implantable covering device, in which the mesh structure protrudes into the cross section of flow in the manner of a funnel at least at the proximal longitudinal end. In the case of the permanently implantable covering device 12, in contrast, the mesh structure 14 lies against the vessel wall along the entire length and applies a radial force to it.

[0124] Furthermore, at least a portion of the mesh structure 14 is provided with a covering 20. The covering 20 is produced from an electrospun fabric and forms a porous membrane. The electrospun fabric is adapted in a manner such that it endows the covering with a membrane function. The porous membrane is formed in a manner such that it can be penetrated by the delivery means for the application of the embolisation means. In addition, the membrane is adapted so that in the penetrated state, the membrane lies against the outer circumference of the delivery means.

[0125] This is the case with all of the coverings 20 in this application.

[0126] There are a number of possible forms for the covering 20.

[0127] As an example, as can be seen in FIGS. 1 to 16, the covering 20 may extend along part of the length of the mesh structure 14 or over a portion, in particular over at most 80%, in particular over at most 60% and particularly especially over at most 40% of the total length L of the mesh structure 16. The total length L of the mesh structure is shown in the figures and extends between the outermost axial longitudinal ends along the central line of the mesh structure.

[0128] This means that in the implanted state, the covering 20 is located only within the region of the opening 28 of the aneurysm 4, so that cells and/or side vessels bordering the aneurysm 4 are not covered by the covering 20. In this manner, the cells and/or the side vessels can still be supplied with blood and therefore with nutrients because of the mesh structure 14 formed with cells.

[0129] As can clearly be seen in the figures, the covering 20 is substantially centrally disposed, i.e. in the region of the axial centre of the mesh structure 14. In other words, the longitudinal axial ends of the covering 20 are approximately equidistant from the proximal and distal longitudinal ends 16, 18 of the mesh structure 14.

[0130] The contour of the longitudinal ends of the covering 20 which extends in the circumferential direction of the mesh structure 14 substantially corresponds to the contour of the proximal and distal longitudinal ends 16, 18 of the mesh structure. This feature is disclosed and claimed both in connection with the specific exemplary embodiments as well as in general in connection with other exemplary embodiments which are not shown here.

[0131] The coverings 20 shown in the figures extend over the total circumference of the mesh structure 14. It is also possible, as shown in FIGS. 17, 18, for example, for the covering 20 to cover only a segment of the mesh structure 14 in the circumferential direction, i.e. an angular segment.

[0132] In this regard, the covering 20 serves, in particular when an embolisation means 40 is placed inside the aneurysm 4, to prevent the embolisation means 40 from escaping from the aneurysm 4 following placement, until the blood inside the aneurysm 4 has been clotted by the embolisation means 40 and therefore the aneurysm 4 has been reliably occluded.

[0133] FIGS. 1 to 8 are used to explain how the corresponding exemplary embodiment of the medical set comprising the covering device 12 and the embolisation means 40 is used for the treatment of an aneurysm. The treatment of other vascular malformations is possible in a corresponding manner.

[0134] FIG. 1 shows the covering device 12, for example in the form of a stent, in the permanently implanted state, i.e. after complete release from the delivery system (step 1). The covering device 12 with the covering 20 is disposed over the aneurysm opening 28. The covering 20 covers the aneurysm opening 28. The X-ray markers 56 at both axial longitudinal ends 16, 18 mark the position of the covering device 12.

[0135] As can be seen in FIG. 2, in step 2 a delivery means 44 in the form of a microcatheter is introduced through the lumen of the covering device 12. To this end, in a manner which is known per se, a guidewire 22 is also disposed in the lumen of the covering device 12 through which the delivery means 44 is guided to the treatment site. The guidewire 22 penetrates the covering 20 in the region of the aneurysm opening 28, as can clearly be seen in FIG. 2. In this regard, the membrane function of the covering 20 comes to the fore. This enables perforation or expansion or widening of the pores of the covering by means of the guidewire 22 because of the pores formed through the electrospun fabric. The guidewire 22 penetrates the material of the covering 20, wherein the corresponding pore or pores which are penetrated by the guidewire 22 is or are widened. This forms the opening 24 through which the guidewire 22 is pushed into the interior of the aneurysm 4.

[0136] FIG. 3 shows that the delivery means 44 is pushed further forwards into the aneurysm 4 via the guidewire 22. In this state, the delivery means 44, specifically the distal free end of the delivery means 44, protrudes into the aneurysm 4. In doing this, the delivery means 44 penetrates the covering 20 in the region of the opening 24 which has already been formed by the guidewire 22. The opening 24 is widened further by the delivery means 44 to the external diameter of the delivery means 44. The widened opening 24 lies closely alongside the outer contour of the delivery means 44 and therefore seals the aneurysm 4 against the lumen of the covering device 12.

[0137] This is made possible by the membrane-like construction of the covering 20, specifically by the electrospun fabric which has an elasticity such that the material around the penetrated pore/the penetrated pores or around the opening 24 are sufficiently elastically deformed.

[0138] In accordance with FIG. 4, in step 4, the guidewire is withdrawn from the delivery means 44 so that the free end of the delivery means 44 is placed in the aneurysm 4 and has a free lumen for the application of the embolisation means 40.

[0139] FIG. 5 shows that in step 5, the embolisation means 40, specifically a coil wire 42, is delivered to the aneurysm through the delivery means 44 and the opening 24 in the covering 20.

[0140] In step 6, as can be seen in FIG. 5, the aneurysm 4 is filled with the embolisation means 40 or the coil wire 42. In this state, the covering 20 already retains the embolisation means 40 in the aneurysm. In addition, the covering 20 seals the aneurysm 4 in the region of the opening 24 against the lumen of the covering device 12, because the opening 24 lies closely alongside the external diameter of the delivery means 44. Escape of the embolisation means 40 is therefore avoided because of the application.

[0141] After the aneurysm has been sufficiently filled with the embolisation means 40, the delivery means 44 is removed from the lumen of the covering device 12, as can be seen in FIG. 7 (step 7). FIG. 7 clearly shows that the opening 24 contracts. The contracted opening 24 has a smaller diameter than the external diameter of the delivery means 44. This means that the embolisation means 40 is securely retained in the aneurysm 4. It is not absolutely necessary for the opening 24 to be completely contracted and the original pore size is regained. It is sufficient for the opening 24 to contract far enough for the contracted opening 24 to prohibit the embolisation means 40 from gaining access to the lumen of the covering device 12. The coils/hydrogels or, more generally, the embolisation means delivered through the delivery means correspond to approximately the internal diameter of the delivery means. When the opening becomes smaller after removal of the delivery means, the embolisation means, i.e. the coil or the hydrogel cannot escape through the opening.

[0142] FIG. 8 shows the final state after the delivery means 22 has been completely removed and the covering device 12 retains the embolisation means 40 in the aneurysm 4.

[0143] It is possible to carry out steps 1 to 8 in the same operation, i.e. in chronological succession and contiguously. It is also possible to initially implant only the covering device, as can be seen in FIG. 1, without initially carrying out steps 2 to 8. If it turns out that the treatment outcome is not yet sufficient, then the treatment of the aneurysm with an embolisation means 40 can be carried out at a later time without problems. This means that in a second, chronologically later operation, steps 2 to 8 may be carried out. The medical set comprising the covering device and the embolisation means therefore enables flexible and appropriate methods for the treatment of aneurysms to be carried out.

[0144] A further exemplary embodiment is shown in FIGS. 9 to 16. This exemplary embodiment is distinguished from the exemplary embodiment of FIGS. 1 to 8 in that instead of the coil wire 42, another embolisation means 40 is used, namely a liquid embolic 46. The application of the liquid embolic 46 is carried out, in similar manner to the application of the coil wire 42. In this regard, reference should be made to the discussions regarding FIGS. 1 to 8.

[0145] In this exemplary embodiment, the opening 24 is contractable in a manner such that after removing the delivery means 44, an opening remains in the covering 20 which is sufficiently small to prevent the liquid embolic 46 from escaping. Here again, the opening 24 does not have to be completely closed in order to achieve the desired result.

[0146] FIG. 17 shows the mesh structure 14 of an exemplary embodiment in accordance with the invention in the implanted state, wherein the covering 20 is disposed on the mesh structure 14 in the region of the neck of the aneurysm and covers it. The covering 20 is disposed on a portion of the circumference or on an angular segment of the mesh structure 14. In this example, the fabric or the covering 20 covers approximately half the circumference of the mesh structure 14 or stent. Another degree of coverage, i.e. more or less than half the circumference of the mesh structure 14, is possible.

[0147] In this manner, perfusion of cells and/or side vessels neighbouring the aneurysm 4 is further optimized, because in this manner, preferably, only the opening 28 of the aneurysm 4 is covered and also, cells and/or side vessels at the same level as the aneurysm can still be supplied with blood and nutrients. In this manner, for example, a side vessel which is disposed opposite the aneurysm 4 can be supplied with blood.

[0148] As can be seen in FIG. 17—in contrast to FIG. 18—no pores other than the pores formed by electrospinning are provided in the fabric. The properties of the fabric are therefore determined only by the pores formed in the electrospinning production process.

[0149] FIG. 18 shows a further exemplary embodiment of the invention, in which the mesh structure 14, as in FIG. 17, is implanted for the treatment of an aneurysm. In contrast to FIG. 17, the covering 20, in particular the fabric, is applied to the entire circumference of the mesh structure 14 and in fact by electrospinning. A portion of the covering 20, specifically the portion of the covering 20 which is opposite to the neck of the aneurysm, is perforated in addition to the pores 52 formed by electrospinning. This is carried out by a post-treatment of the fabric, for example by laser cutting or thermal widening using a laser. The further pores 54 formed in the fabric in this way are larger than the pores formed by the electrospinning, as can be seen in FIG. 18. In the example of FIG. 18, four further pores 54 are formed per cell. The number of the further pores 54 may vary. In contrast to the pores 52 formed by electrospinning, the pores 54 are geometrically defined, for example round. This is made possible because of the laser cutting or thermal widening or thermal melting using a laser.

[0150] The additional perforation of the fabric allows for targeted influencing of the perfusibility of the fabric, for example in order to improve the blood supply to side branches, without compromising the treatment of the aneurysm thereby.

[0151] As can be clearly seen in FIGS. 17, 18, X-ray markers 56 are provided in the medical set 2 and in particular in the mesh structure 14. The X-ray markers 56 are disposed on the cell tips of the marginal cells of the mesh structure 14. Specifically, the X-ray markers 56 may be formed as radiopaque sheaths, for example produced from platinum or gold, which are crimped onto the cell tips of the marginal cells. FIGS. 17, 18 show that three X-ray markers 56 are disposed on each longitudinal end of the mesh structure 10.

[0152] The covering devices 14 in accordance with FIG. 17 and FIG. 18 are combined with an embolisation means 40 to form a medical set. In turn, the set can be combined with a delivery means 44 to form a system.

[0153] The aforementioned embodiments, in particular as regards the extent of the covering 20 along a length L of the mesh structure 14 and as regards an extent of the covering 20 along a circumference of the mesh structure 14, may be combined in any configuration and may be combined in any configuration. Thus, for example, an embodiment is also possible in which the covering 20 extends over the entire length L of the mesh structure, but also extends over only a portion of the circumference of the mesh structure 14.

LIST OF REFERENCE INDICATORS

[0154] 2 medical set

[0155] 4 aneurysm

[0156] 6 vessel

[0157] 8 free

[0158] 10 treatment site

[0159] 12 covering device

[0160] 14 mesh structure

[0161] 16 proximal longitudinal end

[0162] 18 distal longitudinal end

[0163] 20 covering

[0164] 22 guidewire

[0165] 24 opening

[0166] 26 free

[0167] 27 circumferential surface

[0168] 28 opening of aneurysm

[0169] 30 free

[0170] 32 free

[0171] 34 webs

[0172] 36 cell

[0173] 40 embolisation means

[0174] 42 coil wire

[0175] 44 delivery means

[0176] 46 liquid embolic

[0177] 48 free

[0178] 50 free

[0179] 52 pore

[0180] 54 further pores

[0181] 56 X-ray marker

[0182] L length