JP2013099574A - Endoprosthesis for vessel bifurcation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an expansion type device treating the morbidity of a bifurcation section by sufficiently supporting a vessel wall and making it comparatively easy to arrange.SOLUTION: In a system for carrying the device treating the bifurcation section where a body conduit is separated into at least two secondary conduits and where the section of the main conduit increases up to a junction region with the secondary conduits, this expansion type device 1 includes an expandable first stent body configured to engage with a primary conduit in the bifurcation section, the first stent body is radially self-expandable, and has a first end part having a substantially conical shape in a state that the first stent body is prescribed sufficiently self-expanded state and a larger diameter than a second end part, and the first stent body is formed so as to accord with the section of the main conduit increasing in a direction of at least one secondary conduit in the section of an expansion transition zone of a bifurcation where the main conduit is separated from the secondary conduits.

Description

  The present invention relates to an apparatus and kit for treating a body conduit in a bifurcation area, ie, an area where a main conduit separates into two secondary conduits. The invention also relates to an apparatus for arranging this device.

  The devices and kits of the present invention provide vascular bifurcations, especially carotid, femoral, iliac, popliteal, renal or coronary bifurcations, or non-vascular bifurcations such as tracheal biliary or biliary bifurcations, for example It can be used to treat the common bile duct and gallbladder duct, or the branch area of the main bile duct.

  Treatment may include normal arteriosclerosis or endocellular proliferation in correcting a local or nonlocal incision in the conduit wall, or in the case of an aneurysm, removing a normal diameter bifurcation while removing the aneurysm sac. The purpose is to re-establish the appropriate diameter of the bifurcation during regeneration.

  It is known that straight vessel stenosis is treated by a radially expandable tubular device commonly referred to as a stent. This device is introduced into the inner lumen of the blood vessel in an unexpanded state, particularly by the percutaneous route, as long as it is in the area of stenosis. Once in place, it expands in such a way as to support the tube wall and thus re-establish the proper cross section of the tube.

  The device can be made of an inelastic material, in which case it is expanded by an inflatable balloon with which it engages, or it is self-expanding, i.e. it is made of an elastic material and pulled out of the sheath that holds it in a deflated state. If it is, it may expand spontaneously.

  U.S. Pat. No. 4,733,665 and U.S. Pat. No. 4,886,062 describe existing devices and corresponding placement techniques.

  Conventional stents are not perfectly suitable for the treatment of stenosis located in the bifurcation area. This is because by engaging both one of the main and secondary conduits, the other secondary conduit can cause blockage immediately or late.

  It is known to reinforce vessel bifurcations using devices comprising two elements, each formed by a helical winding of metal filaments. One of the two elements has two parts of diameter corresponding respectively to the diameter of the main vessel and one of the secondary vessels, on the one hand engaging this main vessel and on the other hand this secondary vessel It is intended to engage the vessel. The other element has a diameter corresponding to the diameter of the other secondary vessel, and after placing the first element in place, turns one or more turns of itself into the turns of the first element. The first element is connected by being engaged.

  This device allows for strengthening of the bifurcation, but is unsuitable for the treatment of vascular stenosis or occlusive injury in view of its structure and the low likelihood of the two components expanding radially It seems to be.

  Furthermore, the shape of the first element does not correspond to the shape of the bifurcation having an enlarged transition zone between the end of the main vessel and the end of the secondary vessel. Thus, the device cannot adequately support the wall or treat an incision in the area of the wall. Also, it seems relatively difficult to place these two elements separately.

  US Patent No. 5,683,449 to Marcade (Marcade) is a series of articles that are separated from each other and delivered into a cavity and then assembled to form a well-supported structure. Discloses a bifurcated graft formed from individual components. The system includes a base member and one or more grafts connected thereto. Marcade's system stacks the components to achieve a well-supported structure and secure the components together, thereby assuring a reliable assembly and minimizing the possibility of leakage. Need to connect. Marcade further discloses that systems and methods that do not use such overlapping systems are prone to acute and chronic dysfunctions in which the graft may migrate or collapse.

  US Pat. No. 6,068,655 (Patent Document 4) to Seguin et al. Discloses a first segment that is conical in shape, at least one secondary segment, and flexibility between segments. An apparatus having a sexual connection is disclosed. The flexible link allows adjustment of the segments relative to each other, but holds them in relation to each other while limiting their independent placement.

U.S. Pat. No. 4,733,665 US Pat. No. 4,886,062 US Pat. No. 5,683,449 US Pat. No. 6,068,655

  Prior art devices are not sufficient to treat areas of vascular bifurcation as they require direct or indirect connections between multiple device segments. This connection forces the segments to be aligned relative to each other, rather than aligned according to the shape and curvature of the branched conduit being treated. This reduces the flexibility of the device. Also, segments that are directly adjacent or connected to overlap further reduce the flexibility of the device. Such a device is problematic for treating a branched secondary conduit having an axis perpendicular to the axis of the main conduit, for example.

  The present invention provides a variety of devices by making available a device that can treat the pathological condition of the bifurcation area by sufficiently supporting the vessel wall and making it relatively easy to deploy. The aim is to overcome these drawbacks.

  The apparatus to which the present invention relates comprises a conical segment shaped to match the shape of the bifurcation of the area of the enlarged transition zone. The conical segment is in the region of the vessel bifurcation and is shaped to coincide with the increasing cross section of the main conduit facing it.

  In embodiments, the distal end of the stent can expand to a diameter of at least about 105% of the diameter of the proximal end of the stent. In embodiments, the distal end of the stent can expand to a diameter of at least about 110% of the diameter of the proximal end of the stent.

  In an embodiment, the device comprises only a body (i.e., a segment) having a truncated shape that matches the shape of the bifurcation of the area of the enlarged transition zone that separates the main conduit from the secondary conduit in a predetermined expanded state. . This method requires only one stent to treat the vessel bifurcation, thus eliminating the need for surgical insertion, placement and adjustment of multiple stent segments.

In an embodiment, the device is:
At least one radially expandable segment having a cross section substantially larger than the cross section of one secondary conduit in a predetermined expanded state;
A segment having a truncated shape that matches the shape of the branch in the area of the enlarged transition zone separating the main conduit from the secondary conduit in a predetermined expanded state.

  In these embodiments, the segments do not overlap each other, are not connected together, and preferably do not include means for being connected together. In this way, optimal placement of stent segments independently of each other can be achieved. For the purposes of this application, an “unconnected segment” refers directly or indirectly to any other surgical device, such as an additional stent or segment, when the independent segment is in a predetermined, fully expanded state. It is defined as an independent segment that is not connected by any means.

  For simplicity, a segment having a cross-section substantially larger than the cross-section of one secondary conduit in the expanded state is hereinafter referred to as a “secondary segment”, while a segment having a truncated shape in the expanded state. Hereinafter referred to as “cut segment”.

  In an embodiment, a conical stent body can be placed in a kit for treating a vascular bifurcation region with a packaging element. In an embodiment, the kit may include only a conical stent body and packaging element. Alternatively, the kit may further comprise at least one second stent body.

  The secondary segment is introduced into the secondary conduit in a contracted state and is intended to support the wall of the conduit in an expanded state. This expansion not only makes it possible to treat a stenosis or incision in the area of this conduit, but also ensures complete fixation of the device in the conduit.

  In this position of the device, the cut segment supports the wall of the conduit and delimits the extended transition zone of the bifurcation that it can fully support. Thus, a stenosis or incision that occurs at this site can be treated with this device evenly supporting the vessel wall and thus without the risk of damaging the wall.

  Two segments that do not overlap and are not connected are properly aligned independently of each other while expanding.

  In an embodiment, at least the cut segment is covered by a wall, thereby rendering the segment impervious in the radial direction.

  This wall captures particles resulting from the injury being treated, such as arteriosclerotic particles or cell clumps, between it and the wall of the conduit, and thus prevents these particles from moving in the body Make it possible.

  Furthermore, the device can allow treatment of an aneurysm by directing fluid through the bifurcation, thereby preventing compression of the walls that form the aneurysm.

  The segments can be made from tubes of various diameters, with the cut segment tubes having a larger diameter than the secondary segment tubes. The tubes may be made of the same material. Using different diameter tubes will cause the cut segment to have a greater radial force, especially in the larger diameter section.

  Alternatively, the segments can be made from one tube with various cutting patterns to have different shapes and sizes.

  The device can comprise several secondary segments arranged one after the other in order to ensure auxiliary support of the wall of the secondary conduit. For this purpose, the device can comprise at least one radially expandable segment on the side of the cut segment towards the main conduit that has a cross section substantially larger than the cross section of the main conduit in the expanded state.

  According to an embodiment of the present invention, the device segments have a mesh structure, the meshes are long in the machine direction, each mesh has a substantially hexagonal shape, and the cut segment meshes are In the longitudinal sense, it has a progressively increasing width in the direction of the end of this segment having the largest cross section in the expanded state.

  This increase in the width of the mesh may increase the length of the edges of the meshes arranged in the longitudinal direction and / or increase the angle formed between two facing edges of the same mesh. It is a result.

  Also, the cut segment may have an axis that is not coincident with the longitudinal axis of the secondary segment and is inclined with respect to this axis in order to best fit the anatomy of the bifurcation being treated.

  The device can be made of shape memory metal. This metal is preferably a nickel / titanium alloy known by the name NITINOL.

  The equipment in which the device is placed comprises means that allow the device to be expanded when the device is in place. This means includes a removable sheath disposed in the device in a contracted state if the device is made of an elastic material, or if the device is made of an inelastic material, The device includes a support core with an inflatable balloon disposed thereon.

  In any case, according to the present invention, the device identifies the vertical position of the cut segment in the patient's body so that the cut segment can be correctly positioned in the area of the enlarged zone of the bifurcation. Means for making it possible.

  If the expansion of this segment is not the same with respect to the axis of the device, the instrument additionally adds the device for the bifurcation in the patient's body so that that portion of this segment that is maximally expanded can be positioned in an appropriate manner with respect to the bifurcation Means are provided which make it possible to identify the angular direction.

FIG. 3 is a side view of it according to the first embodiment. 1 is a perspective view of a device of the present invention in a radially contracted state, and a device with a portion of the device for placement of the device. It is sectional drawing of the vertical direction of the branch part to treat. Fig. 4 is an illustration of this bifurcation similar to Fig. 3 between three successive stages of placing the device of the present invention. Fig. 4 is an illustration of this bifurcation similar to Fig. 3 between three successive stages of placing the device of the present invention. Fig. 4 is an illustration of this bifurcation similar to Fig. 3 between three successive stages of placing the device of the present invention. Fig. 4 is a view similar to Fig. 3 of a bifurcation with an aneurysm in which the device of the present invention is placed. It is a side view of the apparatus by 2nd Embodiment.

  In order to ensure that the present invention is fully understood, the present invention is further described below with reference to the accompanying drawings. This drawing shows, by way of non-limiting example, an embodiment of an apparatus according to the present invention.

  FIG. 1 shows an expandable device 1 that allows treatment of a body conduit in a bifurcation area, ie, an area where the main conduit 2 separates into two secondary conduits 3 as shown in FIG.

  In an embodiment, the device 1 comprises a conical segment having a proximal end 5 and a distal end 6 and at least one secondary segment having a proximal end 7 and a distal end 8, each mesh structure comprising: As shown in FIG. 9, they do not overlap and are not connected.

  The mesh 10 of these segments is elongated in the longitudinal direction of the device 1 and in each case has a substantially hexagonal shape.

  The proximal end 5 of the conical segment has a tubular shape and has a diameter substantially larger than the diameter of the main conduit 2.

  The distal end 6 of the conical segment has a distal end located on the opposite side of the proximal end 5 in the longitudinal sense of the device 1 on the one hand compared to the width of the mesh of the proximal end 5. 6 has a mesh 10 that progressively increases in the direction of the ends.

  The increase in the width of the mesh 10 in the horizontal direction increases the length of the edge 10a of the mesh 10 arranged in the vertical direction and increases the angle formed between the two facing edges 10a. caused by.

  This conical segment thus has a cutting shape with an axis that is inclined with respect to the longitudinal axis of the device 1. This shape corresponds to the shape of the branch in the area of the enlarged transition zone 11 separating the end of the main conduit 2 from the end of the secondary conduit 3.

  In various alternative embodiments, the conical segment may taper continuously from the proximal end to the distal end, and the taper may vary accordingly.

  The proximal end 7 and the distal end 8 of the secondary segment have the same diameter, which is substantially larger than the diameter of one of the secondary conduits 3.

  The device 1 is made by appropriately cutting a nickel / titanium alloy sheet known as Nitinol, then bending the resulting blank into a ring and welding the parts of this blank close to each other. Can do.

  This alloy is malleable at temperatures on the order of 10 ° C., but can return to a neutral shape at temperatures that closely match the temperature of the human body.

  FIG. 2 shows the device 1 in a radially contracted state, obtained by cooling the constituent materials. During this contraction, the edge 10a pivots with respect to the lateral edge 10b of the mesh 10 so that the mesh 10 has a substantially rectangular shape in this contracted state.

  Due to this contraction, the segments 5 have a smaller cross section than the cross sections of the conduits 2 and 3 and can be introduced into them as described below.

  The device 1 engages on a central support core 15 and then contracts radially on the core. The core 15 includes an axial joint such as a shoulder (not visible in FIG. 2) that has a diameter smaller than that of the device 1 when the device is expanded, but larger than the diameter of the device 1 when the device is contracted. . As a result, this joint allows an axial immobilization of the device 1 on the core 15 when the device contracts.

  Next, the exterior 16 engages with the device 1 to hold the device 1 in a contracted state. The sheath 16 can include four radiopaque markers 20, 21, 22, 23, for example, including a barium compound stamped thereon. The three markers 20, 21, and 22 have an annular shape 5 and extend around the entire periphery of the exterior 16. These are each located in the area of the free end of the segment. The fourth marker 23 is located at a substantially middle point of the bus bar of the segment 6. It has a diamond shape and is thin.

  The core 15 has a longitudinal bore that allows it to engage on the guidewire 25 (FIGS. 4-6). This wire 25 can be engaged by a percutaneous route in the conduit 2 through which it can slide, through the zone 11 and then to one of the conduits 3 and consists of the core 15, the device 1 and the sheath 16. A synthetic material cone 26 is provided in front of the assembly.

  The bifurcation 30 shown in FIG. 3 has a pathological growth 31 that causes stenosis in cross section, which prevents the flow of liquid circulating in the conduits 2 and 3. In the case of vascular bifurcations, these pathological growths are due to, for example, arteriosclerosis or cell proliferation.

  The device 1 enables treatment of this bifurcation by re-establishing the appropriate diameters of the conduits 2, 3 and the expansion zone 11.

  Optionally, depending on whether reinforcement is required in the secondary conduit, the conical segment may be used alone in an enlarged area of the bifurcation, or may be used with one or more secondary segments.

  In practice, as seen in FIG. 4, the assembly consisting of core 15, device 1 and sheath 16 engages wire 25 up to cone 26. The wire 25 allows for the engagement of the assembly into the conduit 2, zone 11, and then the conduit 3, and subsequent guidance, due to its sliding action. The cone 26 facilitates sliding of the assembly and reduces the risk of trauma.

  The marker 22 makes it possible to visualize the position of the cone segment and thus the position of the cone segment so that the cone segment can be correctly positioned with respect to the magnification zone 11 using a suitable X-ray apparatus. To.

  Use of the markers 20 and 21 can ensure that the segments are correctly placed in the main conduit 2 and the secondary conduit 3.

  The marker 23 can be seen in a plan view or a side view depending on whether it is aligned in a direction perpendicular to the radius of the X-ray imaging apparatus or in a parallel direction. It is thus possible to identify the angular orientation of the device 1 with respect to the bifurcation 30 and the portion of the conical segment that extends to the maximum can be arranged in a suitable manner with respect to the zone 11.

  To allow full expansion of the device 1, the sheath 16, which is long enough to open beyond the opening that allowed the introduction of the assembly, is then progressively moved, as shown in FIGS. 5 and 6. Pull out. The device can be warmed up again by body temperature, allowing it to expand, or it can be expanded by a simple spring force without temperature effects. After the device 1 is fully expanded, the core 15 and wire 25 are withdrawn.

  FIG. 7 shows that the device 1 can also be used to treat an aneurysm 40. At least a portion of the conical segment is covered by a polyester membrane 41 that is impermeable to the liquid circulating in the conduit, which membrane is sewn to them, for example. Thus, the device guides this liquid through the bifurcation 30 and, as a result, prevents compression of the walls forming the aneurysm 40.

  FIG. 8 shows a device 100 according to the invention having segments 105, 106, 107, 108 having a structure similar to that of segments 5-8 of the device shown in FIG.

  In the apparatus 100, each segment includes six omega-shaped bridges 190. The curved central portions 190a of these bridges 190 have multi-directional elasticity that allows the various segments to be oriented in the proper longitudinal direction relative to each other.

  The advantage of these bridges 190 is to provide longitudinal continuity to the individual segments and thus the device, which facilitates the device passing through highly curved zones and allows the device to pass through. This eliminates the need to reduce this curvature, which is always dangerous in the case of arteriosclerosis.

  Thus, the present invention provides an apparatus that allows treatment of a pathological condition in the area of the bifurcation 30. These devices have many of the advantages mentioned above, in particular that they ensure complete support of the vessel wall and are relatively simple to deploy.

  It goes without saying that the invention is not limited to the embodiments described above by way of example, but instead encompasses all different embodiments.

  Thus, the devices 1 and 100 can comprise only one conical segment, or one to ensure supplemental support and increase the holding power of the device in the bifurcation 30 if necessary. A conical segment and one or several successively arranged secondary segments can be provided.

  The core 15 expands the device 1 when the device 1 is made of an inelastic material, or the entire expansion of the self-expanding device 1 after the self-expanding device 1 is put in place. To ensure, an inflatable balloon can be provided.

  Markers 20-23 can be stamped on the core 15 or directly on the device 1.

  The conical segment may have an axis that coincides with the longitudinal axis of the device and is not inclined with respect to this axis, as required by the anatomy of the bifurcation being treated.

  Also, the secondary segment itself can have an expanded shape that, in its expanded state, matches the shape of the expanded connection zone that connects the secondary conduit 3 to the expanded transition zone 11 at a particular branch. The secondary segment thus has a shape that matches the shape of the extended connection zone, ensuring its full support.

  The total number of bridges 190 may be more or less than six and may have a shape other than an omega shape that allows multi-directional elasticity, in particular a V-shape or a W-shape.

  As described above, the conical stent body can be packaged with a packaging element in a kit for treating an area of a vessel bifurcation. In an embodiment, the kit may include only a conical stent body and a packaging element. Alternatively, the kit may further comprise at least one second stent body.

The described stent system can be configured to treat any number of bifurcations of a patient, as described above. For example, bifurcations of both the left coronary artery and the right coronary artery, bifurcations of the rotating artery, carotid artery, femur, iliac, popliteal, kidney or coronary artery bifurcation. Alternatively, the device can be used in a branch other than a blood vessel, such as a tracheal branch or a biliary branch, for example, between the common bile duct and gallbladder duct, or in the area of the main bile duct branch.

Claims (20)

A system for transporting a device for treating a bifurcation area in which a main body conduit is separated into at least two secondary conduits and the main conduit increases in cross-section to the junction with the secondary conduit,
A placement device and said device,
The apparatus comprises an expandable first stent body configured to engage a primary conduit at a bifurcation section;
The first stent body is radially self-expandable and has a first end having a substantially conical shape and a larger diameter than the second end in a predetermined fully self-expanded state. ,
The first stent body is shaped to coincide with a cross section of the main conduit increasing in the direction of at least one secondary conduit in the area of the extended transition zone at the bifurcation point separating the main conduit from the secondary conduit;
The first stent body is cut from a single tube;
The first end extends in the direction of the secondary conduit when expanded,
When the first stent body is in a predetermined, sufficiently self-expanded state, the first stent body is shaped independently of the other stent body and without means to connect to the other stent body;
A system wherein the placement device is capable of carrying the stent.   The system of claim 1, wherein the placement device comprises a delivery catheter. And further comprising at least one radially expandable second stent body having a substantially cylindrical shape in a predetermined fully expanded state,
The system of claim 1, wherein the second stent body is configured to engage the secondary conduit. The first stent body is configured to engage only the main conduit;
The system of claim 3, wherein the at least one second stent body is configured to engage only one secondary conduit. The first and second stent bodies are made of first and second material tubes, respectively;
The system of claim 3, wherein the second tube has a larger diameter than the first tube.   The system of claim 5, wherein the tubes are made of the same material.   In addition, a plurality of radially expandable second stent bodies that can be sequentially disposed within the secondary conduit and having a cross-section substantially larger than the cross-section of the secondary conduit in a predetermined expanded state. The system of claim 1, comprising: The first and second stent bodies have a mesh structure formed by a mesh that is long in the longitudinal direction of the device;
Each mesh has a substantially hexagonal shape;
The mesh of the second segment has a gradually increasing width in the longitudinal direction of the device, and the mesh toward the end of the first stent body has a maximum cross section in the expanded state. A system according to any of the above.   9. Further comprising at least one radially expandable third segment having, in an expanded state, a substantially cylindrical shape and a cross section substantially larger than the cross section of the secondary conduit. A system according to any of the above.   10. A system according to any preceding claim, wherein the diameter of the first stent body decreases continuously from its first end to its second end.   10. A system according to any preceding claim, wherein the first end is substantially conical and the second end is substantially cylindrical.   The system according to claim 1, wherein the first stent body is cut from a single tube in various cut patterns.   The system according to claim 1, wherein the first stent body is made of a nickel-titanium alloy.   The system according to claim 1, wherein the first stent body is carried by the placement device.   15. The system of any of claims 1-14, wherein the placement device comprises a support core configured to support the first stent body in a contracted state.   The system of claim 15, wherein the support core comprises an axial joint that allows an axial immobilization of the first stent body when the first stent body contracts.   17. A system according to claim 15 or 16, comprising a marker on the support core, the first stent body, or both.   18. A system according to any of claims 15 to 17, wherein the support core comprises a longitudinal bore such as a lumen that engages on a guide wire.   19. A system according to any preceding claim, wherein the placement device further comprises means for identifying a longitudinal position of the first stent body relative to the bifurcation. 20. A system according to any preceding claim, wherein the placement device further comprises means for identifying an angular orientation of the first stent body relative to the bifurcation.

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