WO2020079825A1

WO2020079825A1 - Catheter

Info

Publication number: WO2020079825A1
Application number: PCT/JP2018/038972
Authority: WO
Inventors: 俊彦塚本; 知也沢田; 築國安; 高歓山口; 盛貴荻堂
Original assignee: 朝日インテック株式会社
Priority date: 2018-10-19
Filing date: 2018-10-19
Publication date: 2020-04-23

Abstract

Provided is a catheter in which a retro-side guide wire can be easily inserted into a first hollow shaft side. The catheter comprises: a first hollow shaft 10; a tubular mesh member 20 that is joined at the proximal end to the distal end of the first hollow shaft 10 and configured to expand or contract in the radial direction; a distal end tip 30 that is joined to the distal end of the mesh member 20; a core wire 50 that is joined at the distal end to the distal end tip 30 and extends inside the mesh member 20 and the first hollow shaft 10 such that the proximal end of the core wire is located closer to the proximal end side than the proximal end of the first hollow shaft 10; a second hollow shaft 40 that is joined at the distal end to the distal end tip 30, extends in the space inside the mesh member 20 toward the proximal end side, and has the proximal end located between the proximal end of the distal end tip 30 and the distal end of the first hollow shaft 10; and a restraining portion 60 that restrains the second hollow shaft 40 to the core wire 50.

Description

catheter

The present invention relates to a catheter.

The following procedure is known as a procedure to improve blood flow by removing occluders that block blood vessels, such as chronic total occlusion (CTO: Chronic total occlusion). First, the ante guide wire is inserted by the antegrade approach (approach from the ante side) to form a gap in the CTO or a false cavity under the intima of the blood vessel. Next, a retro guide wire is inserted from the opposite side (peripheral side) of the CTO by the retrograde approach (retro approach), and is pushed into the formed gap of the CTO or into the pseudointimal cavity. This allows the ante-side guide wire and the retro-side guide wire to communicate with each other.

On the other hand, a medical device having a triangular pyramid-shaped funnel at the tip is known as a medical device that easily transports the ante-side guide wire and the retro-side guide wire. When this medical device is inserted from the ante side, the retro guide wire is easily received by this funnel (for example, see Patent Document 1).

US Patent Application Publication No. 2014/0025086

By the way, as a structure for receiving the retro guide wire, by providing a tip chip, a mesh member, and a second hollow shaft on the tip side of the first hollow shaft, and pulling the tip chip and the second hollow shaft in the mesh member by the core wire, A configuration is conceivable in which the mesh member is expanded and the retro guide wire is inserted into the first hollow shaft. However, in the said structure, since the 2nd hollow shaft inclines in the expanded mesh member, insertion of the retro guide wire to the 1st hollow shaft side may be obstructed.

The present invention has been made based on the above circumstances, and an object thereof is to provide a catheter in which a retro guide wire can be easily inserted into the first hollow shaft side.

In order to achieve such an object, a catheter according to an aspect of the present invention is configured such that a first hollow shaft and a proximal end thereof are joined to a distal end of the first hollow shaft and expand or contract in a radial direction. A tubular mesh member, a tip tip joined to the tip of the mesh member, a tip joined to the tip tip, and a base end located closer to the base end side than the base end of the first hollow shaft. A core wire extending inside the mesh member and the first hollow shaft, a tip joined to the tip tip, extending in a space inside the mesh member toward a base end side, and a base end of the tip tip base. A second hollow shaft located between an end and a tip of the first hollow shaft, and a restraint portion that restrains the second hollow shaft to the core wire.

The core wire extends along an inner peripheral surface or an outer peripheral surface of the second hollow shaft,
The restraint portion may be a joint portion that joins the second hollow shaft and the core wire.

The constraining portion may contact the proximal end surface of the second hollow shaft to constrain the proximal end of the second hollow shaft to the core wire.

The second hollow shaft has a cylindrical shape, the core wire is configured to pass through the inside of the second hollow shaft, and the restraint portion has an outer diameter smaller than an outer diameter of the second hollow shaft. A ring member having an annular shape and abutting on the base end surface of the second hollow shaft may be included, and a connecting member that connects the ring member and the core wire may be included.

The core wire extends along an inner peripheral surface or an outer peripheral surface of the second hollow shaft, and the restraint portion is a clip that sandwiches the core wire and the second hollow shaft and restrains the second hollow shaft to the core wire. It may be.

The present invention can provide a catheter in which the retro guide wire can be easily inserted into the first hollow shaft side.

It is a sectional view of the catheter concerning a 1st embodiment, and is a figure showing the state where the mesh member contracted. FIG. 2 is a sectional view taken along line II-II of FIG. 1. It is sectional drawing of the catheter which concerns on 1st Embodiment, and is a figure which shows the state which the mesh member expanded. (A) is a cross-sectional view of the distal end portion of the catheter according to the second embodiment, and (b) is a cross-sectional view taken along line IVb-IVb of (a). (A) is sectional drawing of the front-end | tip part of the catheter which concerns on the modification of 2nd Embodiment, (b) is sectional drawing which followed the Vb-Vb line of (a). It is sectional drawing of the front-end | tip part of the catheter which concerns on 3rd Embodiment. It is sectional drawing of the front-end | tip part of the catheter which concerns on the modification of 3rd Embodiment. It is a figure which shows the modification of a restraint part. It is a figure which shows the other modification of a restraint part.

The catheter according to the embodiment of the present invention will be described with reference to the drawings, but the present invention is not limited to the embodiments described in the drawings.

In the present specification, the term “antegrade guide wire” means, among the guide wires, a guide wire that is pushed forward to a surgical site such as an occlusion site in a blood vessel prior to a catheter, and a “retrograde guide wire”. The term “guide wire” means, for example, a guide wire that comes inside the blood vessel from the distal end side of the catheter.

In addition, in the present specification, the “tip side” refers to the direction along the longitudinal direction of the catheter and the direction in which the tip is positioned with respect to the mesh member. The “proximal end side” refers to a direction along the longitudinal direction, which is opposite to the distal end side. The “tip” refers to the end on the tip side in each member that constitutes the catheter. The “proximal end” refers to the end portion on the proximal end side of each member that constitutes the catheter.

[First Embodiment]
FIG. 1 is a cross-sectional view of a catheter 1 according to a first embodiment of the present invention, showing a state in which a mesh member 20 is contracted.
As shown in FIG. 1, the catheter 1 includes a first hollow shaft 10, a mesh member 20, a distal tip 30, a second hollow shaft 40, a core wire 50, a restraining portion 60, and a connector 70.

The first hollow shaft 10 has a distal shaft 11 and a proximal shaft 12. The tip of the tip shaft 11 is connected to the base end of the mesh member 20. The distal end of the proximal shaft 12 is connected to the proximal end of the distal shaft 11. A connector 70 is connected to the proximal end of the proximal shaft 12.

The tip side shaft 11 has a lumen 13 for inserting the antegrade guide wire, the retrograde guide wire, and the core wire 50 therein. The proximal shaft 12 has a lumen 14 into which the core wire 50 is inserted. At the connecting portion between the distal shaft 11 and the proximal shaft 12, the distal shaft 11 and the proximal shaft 12 form a guide wire port 15 that opens toward the proximal side. A retrograde guidewire is delivered to the exterior of the catheter 1 via the guidewire port 15.

The material forming the first hollow shaft 10 preferably has antithrombogenicity, flexibility, and biocompatibility because the first hollow shaft 10 is inserted into a blood vessel. A metal material is mentioned. Since the distal shaft 11 is required to have flexibility, a resin material is preferable. For example, polyamide resin, polyolefin resin, polyester resin, polyurethane resin, silicone resin, fluororesin, etc. can be adopted. The proximal shaft 12 is preferably made of a metal material because pushability is required. For example, stainless steel such as SUS304, nickel titanium alloy, cobalt chromium alloy, etc. can be adopted.

The mesh member 20 is a tubular member that can be expanded or contracted in the radial direction. When the core wire 50, which will be described later, is pulled toward the proximal end side, the mesh member 20 is deformed out-of-plane and expanded outward in the radial direction as shown in FIG. A retrograde guidewire is received in the catheter 1 through the apertures in the member 20. ‥

In the present embodiment, the mesh member 20 is formed so that a plurality of element wires 21 are knitted in a lattice shape and become a tube shape as a whole. Further, the mesh member 20 has openings between the adjacent braided wires, and receives the retrograde guide wire through the expanded openings when the diameter is increased. The tip 30 and the first hollow shaft 10 are joined to the tip and the base of each element wire 21 that constitutes the mesh member 20.

Here, each of the strands 21 constituting the mesh member 20 may be a single strand or a plurality of strands. For example, from a twisted wire in which a plurality of metal wires having different diameters are twisted together. It may be formed.

A metal material or a resin material can be adopted as a material forming each strand 21 of the mesh member 20. Examples of the resin material include polyamide, polyester, polyarylate, and polyether ether ketone. From the viewpoint of improving strength and flexibility, a metal material is preferable. Examples of the metal material include stainless steel such as SUS304, nickel titanium alloy, and cobalt chromium alloy. The strands of wire may be formed of the same material or different materials.

Further, the material forming each strand 21 of the mesh member 20 may be a radiopaque material from the viewpoint of improving the visibility of the mesh member 20. Examples of the radiopaque material include gold, platinum, tungsten, and alloys containing these elements (for example, platinum-nickel alloy and the like). The radiopaque material may be a combination of the radiopaque material and a material other than this material, such as a material coated on the surface of a material that is not radiopaque.

The guide member 22 is provided on the mesh member 20, and the tip of the guide film 22 is located between the base end of the tip 30 and the tip of the first hollow shaft 10. The guide film 22 smoothly guides the retrograde guide wire received through the openings of the mesh member 20 toward the first hollow shaft 10. The leading end of the guide film 22 is located substantially at the center of the mesh member 20 in the long axis direction, and the base end is located at the end of the first hollow shaft 10. The guide film 22 is formed on the mesh member 20 so as to bridge adjacent strands. Here, the retrograde guide wire is guided into the first hollow shaft 10 through the mesh member 20 by expanding the guide film 22 into a funnel shape when the mesh member 20 expands in diameter. At least a part of the guide film 22 (for example, the outer circumference of the tip of the guide film 22) may be bonded to the mesh member 20, and may be, for example, a film-like member (not shown).

Examples of the material forming the guide film 22 include polyethylene, polyurethane, polyamide, polyamide elastomer, polyolefin, polyester, polyester elastomer and the like. Among these, polyurethane is preferable as the above material from the viewpoint of improving the sliding property of the surface. The method for forming the guide film 22 is not particularly limited. For example, a dip method may be used for the guide film to be arranged on the mesh member 20, a method of fusing the tip of the film to the mesh member 20 for a film-like guide film, and the like. Can be adopted.

The tip 30 is connected to the tip of the mesh member 20. Specifically, the distal tip 30 is formed in a sharpened shape toward the distal side so that the catheter 1 can easily advance in the blood vessel, and each strand of the mesh member 20 is formed at the proximal end of the distal tip 30. Each tip, the tip of the second hollow shaft 40, and the tip of the core wire 50 are embedded.

As the material forming the distal tip 30, it is preferable that the catheter 1 has flexibility because the catheter 1 advances in the blood vessel. Examples of the material having flexibility include resin materials such as polyurethane and polyurethane elastomer.

The second hollow shaft 40 is connected to the tip 30 and projects toward the proximal end in the space inside the mesh member 20. As shown in FIG. 1, the proximal end of the second hollow shaft 40 is located between the distal end of the first hollow shaft 10 and the proximal end of the distal tip 30 in the space inside the mesh member 20. Further, as shown in FIG. 3, the second hollow shaft 40 has its proximal end in the space inside the mesh member 20 in the space inside the mesh member 20 in a state where the mesh member 20 is expanded radially outward. And the base end of the tip 30. This is to make it easier to receive the retrograde guide wire in the first hollow shaft 10.

As the material forming the second hollow shaft 40, since the second hollow shaft 40 is also inserted into the blood vessel similarly to the first hollow shaft 10 described above, it has antithrombotic property, flexibility and biocompatibility. It is preferable to have. Examples of the material include the same materials as those exemplified in the description of the first hollow shaft 10, but a resin material is preferable from the viewpoint of flexibility.

The core wire 50 has its tip connected to the tip 30, and its base extends to the outside of the connector 70 located on the base side of the first hollow shaft 20. Therefore, the core wire 50 penetrates the mesh member 20, the

lumens

13 and 14 of the first hollow shaft 10 and the through hole 71 of the connector 70. When the operator operates the core wire 50 outside the connector 70, the core wire 50 advances and retracts in the major axis direction of the catheter 1, and the mesh member 20 expands and contracts in the radial direction.

The material forming the core wire 50 preferably has sufficient tensile strength and rigidity from the viewpoint of preventing cutting of the core wire 50 itself and surely expanding and contracting the mesh member 20. Examples of the material include stainless steel such as SUS304 and metallic materials such as nickel titanium alloy and cobalt chromium alloy.

2 is a sectional view taken along the line II-II in FIG. The mesh member 20 is not shown in FIG.

As shown in FIGS. 1 and 2, the restraint portion 60 is arranged on the proximal end side of the second hollow shaft 40, and has a ring member 61 and four connecting shafts 62. The ring member 61 has an annular shape, the inner diameter of which is larger than the inner diameter of the second hollow shaft 40 and the outer diameter of which is smaller than the outer diameter of the second hollow shaft 40. The ring member 61 is in contact with the base end surface 41 of the second hollow shaft 40 in a state where its long axis (the axis extending in the longitudinal direction of the catheter 1) is substantially coaxial with the long axis of the second hollow shaft 40. Therefore, the ring member 61 is located within the range of the base end surface 41 of the second hollow shaft 40 when viewed in the long axis direction. That is, the ring member 61 does not have a portion protruding inward and outward of the second hollow shaft 40 in the radial direction. The core wire 50 penetrates the inside of the ring member 61.

As shown in FIG. 2, the four connecting shafts 62 are provided radially at substantially equal intervals around the core wire 50. One end of each connection shaft 62 is joined (welded, welded, or adhered) to the outer peripheral surface of the core wire 50, and the other end of each connection shaft 62 is joined (welded, welded, or adhered) to the base end face 63 of the ring member 61. ) Has been. In this way, the connecting shaft 62 is joined to the core wire 50, the ring member 61 is joined to the connecting shaft 62, and the distal end surface 64 of the ring member 61 is in contact with the proximal end surface 41 of the second hollow shaft 40. As a result, the restraint portion 60 restrains the second hollow shaft 40 to the core wire 50. The four connecting shafts 62 correspond to connecting members. Further, the surface roughness of the distal end surface 64 of the ring member 61 and / or the proximal end surface 41 of the second hollow shaft 40 may be increased to improve the binding force of the second hollow shaft 40 to the core wire 50. Further, the second hollow shaft 40 and the ring member 61 may be joined together. Further, the other end of each connection shaft 62 may be joined to the inner peripheral surface of the ring member 61.

As the material forming the ring member 61 and the four connecting shafts 62, a metal material or a resin material can be adopted. Examples of the resin material include polyamide, polyester, polyarylate, and polyether ether ketone. Examples of the metal material include stainless steel such as SUS304, nickel titanium alloy, and cobalt chrome alloy. The ring member 61 and the four connecting shafts 62 are preferably made of the same material, but may be made of different materials.

The material forming the ring member 61 and the four connecting shafts 62 may be a radiopaque material from the viewpoint of improving the visibility of the ring member 61 and the four connecting shafts 62. Examples of the radiopaque material include gold, platinum, tungsten, and alloys containing these elements (for example, platinum-nickel alloy and the like). The radiopaque material may be a combination of the radiopaque material and a material other than this material, such as a material coated on the surface of a material that is not radiopaque.

The connector 70 is a member for an operator to hold the catheter 1. As shown in FIG. 1, the connector 70 is connected to the proximal end of the first hollow shaft 10 and is a through hole communicating with the

lumens

13 and 14 of the first hollow shaft 1 so that the core wire 50 can be exposed to the outside. 71 and an opening 72 formed at the base end of the through hole 71. The form of the connector 70 is not particularly limited, and may be any shape as long as it is easy for the operator to grip.

Next, an example of a usage mode of the catheter 1 described above will be described.

First, after inserting the antegrade guide wire W1 (not shown) into a blood vessel, for example, push it along the blood vessel to a site where an occluder is present (hereinafter also referred to as “occlusion site”). After the distal end of the antegrade guide wire W1 reaches the occluded region, a balloon catheter (not shown) is inserted to the occluded region using the antegrade guide wire W1 as a guide, and the occluded region is expanded by expanding the diameter of the balloon. . After expanding the occluded part, the balloon is contracted to remove the balloon catheter from the blood vessel.

Next, the proximal end of the antegrade guide wire W1 is passed through the through hole at the distal end of the distal tip 30 and passes through the inside of the distal tip 30 and the second hollow shaft 40 to come out of the catheter 1 from the guide wire port 15. The catheter 1 is inserted into the catheter 1, and the distal end of the catheter 1 is pushed forward to the occlusion site in the blood vessel using the antegrade guide wire W1 as a guide. At this time, the catheter 1 is inserted into a blood vessel in a state where the mesh member 20 has a reduced diameter, and is maintained in the reduced diameter state until the tip of the catheter 1 reaches the occlusion site.

After the distal end of the catheter 1 reaches the occluded site where the balloon catheter is pushed open, the antegrade guidewire W1 is pulled out from the catheter 1 by pulling the antegrade guidewire W1 toward the proximal end side. Then, by pulling the core wire 50 exposed to the outside of the connector 70 toward the proximal end side, the distance between the tip of the mesh member 20 and the tip of the first hollow shaft 10 is narrowed, and as a result, the mesh member 20 is radially moved. It expands out-of-plane and expands in diameter. At this time, in the present embodiment, since the tip of the guide film 22 is joined to the substantially central portion of the mesh member 20 in the longitudinal direction, the guide film 22 is expanded in diameter in accordance with the expansion of the mesh member 20. The membrane 22 has a funnel shape as a whole. Since the mesh opening is expanded as the mesh member 20 is expanded, the retrograde guide wire W2 can be easily received. Further, since the proximal end of the second hollow shaft 40 is restrained by the core wire 50 by the restraint portion 60, the second hollow shaft 40 does not tilt and moves along the long axis direction (longitudinal direction) of the catheter 1. To do. In addition, after the distal end of the catheter 1 reaches the occluded site along the antegrade guide wire W1, the mesh member 20 is expanded in diameter, and then the antegrade guide wire W1 is pulled toward the proximal end side to advance. The sex guide wire W1 may be withdrawn from the catheter 1.

Next, as shown in FIG. 3, the retrograde guide wire W2 coming from the distal end side is received in the catheter 1. As the route through which the retrograde guide wire W2 goes, for example, a false cavity in the blood vessel wall surrounding the occlusion site, a through hole penetrating the occlusion site, or the like is assumed. It may be the wire W2. The retrograde guide wire W2 is received in the space inside the mesh member 20 through the openings of the expanded mesh member 20, and then inserted into the distal end side shaft 11 of the first hollow shaft 10 and through the guide wire port 15. Is delivered to the outside of the catheter 1.

As described above, in the catheter 1, the second hollow shaft 40 is constrained to the core wire 50 by the constraining portion 60. In the present embodiment, the ring member 61 of the restraint portion 60 is in contact with the base end surface 41 of the second hollow shaft 40 to restrain the base end of the second hollow shaft 40 to the core wire 50. Therefore, when the core wire 50 is pulled to expand the mesh member 20, the second hollow shaft 40 can be prevented from being separated from the core wire 50, and the long axis of the second hollow shaft 40 can be prevented from being displaced. . As a result, the second hollow shaft 40 does not hinder the insertion of the retrograde guide wire W2, and the retrograde guide wire W2 can be easily inserted into the first hollow shaft 10 side. Further, since the proximal end of the second hollow shaft 40 is restrained by the core wire 50, when the retrograde guide wire W2 comes into contact with the second hollow shaft 40, the retrograde guide wire W2 is fixed to the second hollow shaft 40. It can be guided along the first hollow shaft 10 side.

The core wire 50 is configured to pass through the inside of the second hollow shaft 40, and the restraint portion 60 has an annular shape having an outer diameter smaller than the outer diameter of the second hollow shaft 40. A ring member 61 that abuts on the base end surface 41 of the above, and a connecting shaft 62 that connects the ring member 61 and the core wire 50. With this, since there is no portion protruding outward of the second hollow shaft 40 in the radial direction, even if the ring member 61 is provided, the ring member 61 does not hinder the insertion of the retrograde guide wire W2 and the retrograde guide wire W2. Can be easily inserted into the first hollow shaft 10 side.

[Second Embodiment]
4A is a sectional view of the distal end portion of the catheter 101 according to the second embodiment of the present invention, and FIG. 4B is a sectional view taken along the line IVb-IVb of FIG. 4A. . The mesh member 20 is not shown in FIG. 4B.

As shown in FIG. 4A, the catheter 101 according to the present embodiment has a first hollow shaft 10, a mesh member 20, a distal end tip 30, a second hollow shaft 40, a core wire 50, and a restraining portion 160. And a connector 70 (see FIG. 1). The catheter 101 of the second embodiment is different from the catheter 1 of the first embodiment in the configuration of the restraint portion 160. Since the configurations of the first hollow shaft 10, the mesh member 20, the tip 30, the second hollow shaft 40, the core wire 50, and the connector 70 are the same as those of the first embodiment, the same parts are The same reference numerals are given and detailed description thereof is omitted.

In the present embodiment, the core wire 50 extends along the inner peripheral surface 42 of the second hollow shaft 40. The base end of the second hollow shaft 40 is joined (welded, welded, or bonded) to the core wire 50 by the restraint portion 160. Whether the base end of the second hollow shaft 40 and the core wire 50 are joined by welding, welding, or adhesion may be appropriately selected according to the material forming the second hollow shaft 40 and the core wire 50. . The restraint portion 160 corresponds to a joint portion that joins the second hollow shaft 40 and the core wire 50.

In the catheter 101 of the present embodiment, the proximal end of the second hollow shaft 40 is restrained with respect to the core wire 50 by the restraint portion 160 which is a joint portion. Accordingly, when the core wire 50 is pulled to expand the mesh member 20, the second hollow shaft 40 can be prevented from being separated from the core wire 50, and the long axis of the second hollow shaft 40 can be prevented from being displaced. . Therefore, the second hollow shaft 40 does not hinder the insertion of the retrograde guide wire W2, and the retrograde guide wire W2 can be easily inserted into the first hollow shaft 10 side. Further, since the proximal end of the second hollow shaft 40 is constrained by the core wire 50, when the retrograde guide wire W2 contacts the second hollow shaft 40, the retrograde guide wire W2 is fixed to the second hollow shaft 40. It can be guided along the first hollow shaft 10 side.

5A is a cross-sectional view of the distal end portion of the catheter 102 according to the modified example of the second embodiment, and FIG. 5B is a cross-sectional view taken along the line Vb-Vb of FIG. 5A. . In addition, illustration of the mesh member 20 is abbreviate | omitted in FIG.5 (b).

In the catheter 102 according to the modified example, as shown in FIGS. 5A and 5B, the core wire 50 extends along the outer peripheral surface 43 of the second hollow shaft 40. The base end of the second hollow shaft 40 is joined (welded, welded, or bonded) to the core wire 50 by the restraint portion 161. Similarly to the above, which of the welding, welding, and adhesion methods is used to join the base end of the second hollow shaft 40 and the core wire 50 depends on the material forming the second hollow shaft 40 and the core wire 50. It may be selected appropriately. The restraint portion 161 corresponds to a joint portion that joins the second hollow shaft 40 and the core wire 50.

In the catheter 102 of this modified example, the proximal end of the second hollow shaft 40 is restrained with respect to the core wire 50 by the restraint portion 161 which is a joint portion. Thereby, also in the said catheter 102, the same effect as the said catheter 101 is produced.

[Third Embodiment]
FIG. 6 is a cross-sectional view of the distal end portion of the catheter 201 according to the third embodiment of the present invention.

As shown in FIG. 6, the catheter 201 according to the present embodiment has a first hollow shaft 10, a mesh member 20, a tip 30, a second hollow shaft 40, a core wire 50, a restraining portion 260, and a connector. 70 (see FIG. 1). The catheter 101 of the second embodiment differs from the catheter 1 of the first embodiment in the configuration of the restraint portion 260. Since the configurations of the first hollow shaft 10, the mesh member 20, the tip 30, the second hollow shaft 40, the core wire 50, and the connector 70 are the same as those of the first embodiment, the same parts are The same reference numerals are given and detailed description thereof is omitted.

In the present embodiment, the core wire 50 extends along the inner peripheral surface 42 of the second hollow shaft 40. A clip serving as a restraining portion 260 is provided at the base end of the second hollow shaft 40, and the core wire 50 and the second hollow shaft 40 are sandwiched between the clips, and the second hollow shaft 40 is restrained by the core wire 50. The material forming the restraint portion 260, which is a clip, preferably has antithrombogenicity, flexibility, and biocompatibility, and examples thereof include a resin material and a metal material. As the resin material, for example, polyamide, polyester, polyarylate, polyether ether ketone, or the like can be adopted. As the metal material, for example, stainless steel such as SUS304, nickel titanium alloy, cobalt chrome alloy, or the like can be adopted.

As described above, in the catheter 201 of the present embodiment, the proximal end of the second hollow shaft 40 is constrained to the core wire 50 by the constraining portion 260 that is a clip. Accordingly, when the core wire 50 is pulled to expand the mesh member 20, the second hollow shaft 40 can be prevented from being separated from the core wire 50, and the long axis of the second hollow shaft 40 can be prevented from being displaced. . Therefore, the second hollow shaft 40 does not hinder the insertion of the retrograde guide wire W2, and the retrograde guide wire W2 can be easily inserted into the first hollow shaft 10 side. Further, since the proximal end of the second hollow shaft 40 is restrained by the core wire 50, when the retrograde guide wire W2 comes into contact with the second hollow shaft 40, the retrograde guide wire W2 is fixed to the second hollow shaft 40. It can be guided along the first hollow shaft 10 side.

FIG. 7 is a cross-sectional view of the distal end portion of the catheter 202 according to the modified example of the third embodiment.

In the catheter 202 according to the modified example, as shown in FIG. 7, the core wire 50 extends along the outer peripheral surface 43 of the second hollow shaft 40. A clip that is a restraint portion 261 is provided at the base end of the second hollow shaft 40, and the core wire 50 and the second hollow shaft 40 are sandwiched between the clips, and the second hollow shaft 40 is restrained by the core wire 50. The material forming the restraint portion 261 which is a clip is the same as the material forming the restraint portion 260 described above.

In the catheter 202 of this modified example, the proximal end of the second hollow shaft 40 is constrained to the core wire 50 by the constraining portion 261 which is a clip. Thereby, also in the said catheter 202, the same effect as the said catheter 201 is produced.

It should be noted that the present invention is not limited to the configurations of the above-described embodiments, and is shown by the scope of the claims, and is intended to include all modifications within the scope and meaning equivalent to the scope of the claims. To be done. For example, a part of the configuration of the above-described embodiment may be deleted or replaced with another configuration, or another configuration may be added to the configuration of the above-described embodiment.

For example, although the connecting shaft 62 of the restraint portion 60 of the catheter 1 of the first embodiment is four, the connecting shaft 62 may be two as in the restraint portion 360 shown in FIG. Even with this configuration, the second hollow shaft 40 can be restrained by the core wire 50. The number of connecting shafts 62 may be other than two or four.

Further, as shown in FIG. 9, the core wire 50 may extend along the outer peripheral surface 43 of the second hollow shaft 40, and the second hollow shaft 40 may be bound to the core wire 50 by the restraining portion 460. The restraint portion 460 includes a rectangular ring member 461 and four connecting shafts 462. The core wire 50 penetrates the inside of the ring member 461, and a part of the ring member 461 is in contact with the base end surface 41 of the second hollow shaft 40.

The four connecting shafts 462 are arranged radially at substantially equal intervals around the core wire 50. One end of each connection shaft 462 is joined (welded, welded, or bonded) to the outer peripheral surface of the core wire 50, and the other end of each connection shaft 462 is joined (welded, welded, or bonded) to the base end face 463 of the ring member 461. ) Has been. The material forming the ring member 461 and the four connecting shafts 462 is the same as the material forming the ring member 61 and the four connecting shafts 62 of the first embodiment, so that the material of the first embodiment is the same. The description is cited and the detailed description is omitted. The restraint portion 460 also prevents the second hollow shaft 40 from separating from the core wire 50 when the core wire 50 is pulled to expand the mesh member 20, and prevents the major axis of the second hollow shaft 40 from shifting. can do. Therefore, the second hollow shaft 40 does not hinder the insertion of the retrograde guide wire W2, and the retrograde guide wire W2 can be easily inserted into the first hollow shaft 10 side. Further, since the proximal end of the second hollow shaft 40 is restrained by the core wire 50, when the retrograde guide wire W2 comes into contact with the second hollow shaft 40, the retrograde guide wire W2 is fixed to the second hollow shaft 40. It can be guided along the first hollow shaft 10 side. The number of connecting shafts 62 may be other than four.

1, 101, 102, 201, 202 Catheter 10 First hollow shaft 20 Mesh member 30 Tip tip 40 Second hollow shaft 41 Base end face 42 Inner peripheral face 43 Outer peripheral face 50

Core wire

60, 160, 161, 260, 261, 360, 460

Restraint portions

61, 461 Ring member 62 Connection shaft

Claims

A first hollow shaft,
A tubular mesh member having a proximal end joined to the distal end of the first hollow shaft and configured to expand or contract in the radial direction;
A tip chip joined to the tip of the mesh member,
A core wire that extends inside the mesh member and the first hollow shaft so that the tip is joined to the tip and the base end is located closer to the base end side than the base end of the first hollow shaft;
A second end having a distal end joined to the distal end tip, extending toward the proximal end side in a space inside the mesh member, and having a proximal end located between the proximal end of the distal end tip and the distal end of the first hollow shaft; A hollow shaft,
A restraint portion that restrains the second hollow shaft to the core wire.
The core wire extends along an inner peripheral surface or an outer peripheral surface of the second hollow shaft,
The catheter according to claim 1, wherein the restraint portion is a joint portion that joins the second hollow shaft and the core wire.
The catheter according to claim 1, wherein the restraint portion is in contact with a base end surface of the second hollow shaft to restrain the base end of the second hollow shaft to the core wire.
The second hollow shaft has a cylindrical shape,
The core wire is configured to pass inside the second hollow shaft,
The restraint portion has an annular shape having an outer diameter smaller than the outer diameter of the second hollow shaft, and connects the ring member that comes into contact with the base end surface of the second hollow shaft, the ring member and the core wire. And a connecting member for connecting the catheter to the catheter.
The core wire extends along an inner peripheral surface or an outer peripheral surface of the second hollow shaft,
The catheter according to claim 1, wherein the restraint portion is a clip that sandwiches the core wire and the second hollow shaft and restrains the second hollow shaft with the core wire.