WO2019234797A1

WO2019234797A1 - Catheter

Info

Publication number: WO2019234797A1
Application number: PCT/JP2018/021379
Authority: WO
Inventors: 俊彦塚本; 高歓山口; 築國安; 知也沢田; 盛貴荻堂
Original assignee: 朝日インテック株式会社
Priority date: 2018-06-04
Filing date: 2018-06-04
Publication date: 2019-12-12

Abstract

The objective of the invention is to provide a catheter capable of ensuring the acceptance of a retrograde guide wire. This catheter 1 comprises: a hollow shaft 11; a tube-shaped mesh member 21 joined at the forward end of the hollow shaft 11 and capable of expanding and contracting in the radial direction; a forward end tip 31 joined at the forward end of the mesh member 21; and a core wire 41 extending through the interiors of the mesh member 21 and the hollow shaft 11 in such a manner that the forward end thereof is joined to the forward end tip 31 and the base end thereof is positioned more toward the base-end than the base end of the hollow shaft 11. A magnet 51 is provided in a part of the core wire 41 that is positioned in the interior of the mesh member 21 when the mesh member 21 expands in the radial direction.

Description

catheter

The present invention relates to a catheter.

The following procedure is known as a technique for improving blood flow by removing a blockage that blocks a blood vessel, such as chronic total occlusion (CTO). First, an antegrade guide wire is inserted by an antegrade approach to form a gap in the CTO or a pseudocavity under the intima of the blood vessel. Next, a retrograde guide wire is inserted from the opposite side (peripheral side) of the CTO by a retrograde approach, and pushed into the formed CTO gap or the subintimal pseudocavity. Thereby, an antegrade guide wire and a retrograde guide wire are made to traffic.

On the other hand, a medical device having a triangular pyramid funnel at the tip is known as a medical device for easily transporting an antegrade guide wire and a retrograde guide wire. If this medical device is inserted by an antegrade approach, a retrograde guidewire can be easily received by this funnel (see, for example, Patent Document 1).

US Patent Application Publication No. 2014/0025086

However, when the above medical device is used for the above procedure, even if monitoring is performed by a monitor, it is difficult to specify the position of the distal end of the retrograde guide wire in the depth direction by the monitor image, and the retrograde approaching is opposed. Sex guidewires cannot be reliably received in the funnel.

The present invention has been made based on the above circumstances, and an object of the present invention is to provide a catheter that can reliably receive a retrograde guidewire.

Some aspects of the disclosure include:
(1) a hollow shaft;
A tubular mesh member joined to the tip of the hollow shaft and expandable / contractable in the radial direction;
A tip chip joined to the tip of the mesh member;
A core wire extending through the mesh member and the interior of the hollow shaft such that a distal end is joined to the distal tip, and a proximal end is located on a proximal side of the proximal end of the hollow shaft;
With
When the mesh member is expanded in the radial direction, a magnet is provided in a portion of the core wire located inside the mesh member.
catheter,
(2) The magnet has a larger outer diameter than the core wire.
The catheter according to (1),
(3) The magnet is opaque to radiation.
The catheter according to any one of (1) and (2), and (4) a guide membrane that is located at the base end of the mesh member and covers a part of the mesh member,
The magnet is provided in a portion of the core wire that is located on the proximal side of the distal end of the induction membrane or the distal end of the induction membrane when the mesh member is expanded in the radial direction.
The catheter according to any one of (1) to (3).

In the present specification, the “tip side” means a direction along the axial direction of the hollow shaft and a direction in which the mesh member is located with respect to the hollow shaft. Further, the “base end side” means a direction along the axial direction of the hollow shaft and opposite to the tip end side. The “tip” refers to the end on the distal end side in an arbitrary member or part, and the “base end” refers to the end on the proximal end in the arbitrary member or part.

The present invention can provide a catheter that can reliably receive a retrograde guidewire.

It is a schematic sectional drawing showing one embodiment of the present invention, and is a figure showing the state where a mesh member is diameter-reduced. It is a schematic sectional drawing which shows the state which the mesh member of FIG. 1 is expanding. It is a schematic sectional drawing which shows an example of the use condition of FIG. It is a principal part expansion schematic sectional drawing which shows the one aspect | mode of the magnet provided in the core wire. It is a principal part expansion schematic sectional drawing which shows the one aspect | mode of the magnet provided in the core wire. It is a principal part expansion schematic sectional drawing which shows the one aspect | mode of the magnet provided in the core wire. It is a principal part expansion schematic sectional drawing which shows the one aspect | mode of the magnet provided in the core wire. It is a principal part expansion schematic sectional drawing which shows the one aspect | mode of the magnet provided in the core wire. It is a principal part expansion schematic sectional drawing which shows the one aspect | mode of the magnet provided in the core wire. It is a principal part expansion schematic sectional drawing which shows the one aspect | mode of the magnet provided in the core wire. It is a principal part expansion schematic sectional drawing which shows the one aspect | mode of the magnet provided in the core wire. It is a principal part expansion schematic sectional drawing which shows the one aspect | mode of the magnet provided in the core wire. It is a schematic sectional drawing which shows one modification of FIG. 1, Comprising: It is a figure which shows the state which the mesh member is diameter-reducing. FIG. 6 is a schematic cross-sectional view showing a state where the diameter of the mesh member of FIG. 5 is expanded. It is a schematic sectional drawing which shows the other modification of FIG. 1, Comprising: It is a figure which shows the state which the mesh member is diameter-reducing. It is a schematic sectional drawing which shows the state which the mesh member of FIG. 7 is expanding.

The catheter includes a hollow shaft, a tubular mesh member that is bonded to the distal end of the hollow shaft and can be expanded and contracted in a radial direction, a distal tip joined to the distal end of the mesh member, and a distal end joined to the distal tip. And a core wire extending through the inside of the hollow shaft so that the proximal end is located on the proximal side of the proximal end of the hollow shaft, and when the mesh member is expanded in the radial direction A magnet is provided in a portion of the core wire located inside the mesh member.

In this specification, “an antegrade guidewire” means a guidewire used to guide the catheter in a body cavity such as a blood vessel, and “a retrograde guidewire” means the inside of the body cavity. It means a guide wire facing toward the catheter.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments described in the drawings.

FIG. 1 is a schematic cross-sectional view showing an embodiment of the present invention, and shows a state where a mesh member is reduced in diameter. As shown in FIG. 1, the catheter 1 is roughly constituted by a hollow shaft 11, a mesh member 21, a tip tip 31, a core wire 41, a magnet 51, a connector 61, and a guide membrane 71. ing.

The hollow shaft 11 is a member that guides the received retrograde guide wire W (see FIG. 3) to the outside of the body. Specifically, the hollow shaft 11 includes, for example, a distal end side shaft 11a joined to a proximal end of a mesh member 21 described later, and a proximal end side shaft 11b continuous to the proximal end of the distal end side shaft 11a. doing. In the present embodiment, a lumen 11c is provided inside the distal end side shaft 11a, and a lumen 11d is provided inside the proximal end side shaft 11b. Further, an opening portion 11f (opening of the proximal end of the distal end side shaft 11a) that opens toward the proximal end side is formed at a boundary portion between the distal end side shaft 11a and the proximal end side shaft 11b. For example, a core wire 41 described later is inserted into the

lumens

11 c and 11 d described above, and a base end thereof is exposed to the outside of the hollow shaft 11 through the opening 612.

The material constituting the hollow shaft 11 is preferably antithrombogenic, flexible and biocompatible because the hollow shaft 11 is inserted into a body cavity such as a blood vessel. Further, as the distal shaft 11a, it is preferable to use a resin material such as a polyamide resin, a polyolefin resin, a polyester resin, a polyurethane resin, a silicone resin, or a fluororesin from the viewpoint of improving flexibility. As the proximal end shaft 11b, it is preferable to use a metal material such as a hypotube, for example, from the viewpoint of improving the pushability of the catheter 1.

The mesh member 21 is a tubular member that is joined to the tip of the hollow shaft 11 and can be expanded and contracted in the radial direction. Specifically, the mesh member 21 is formed of a mesh that can be easily deformed, for example, having a large number of openings 211 through which the retrograde guide wire W can pass. For this reason, when the mesh member 21 pulls a core wire 41 to be described later toward the proximal end side, the mesh member 21 expands by expanding to the outside of the diameter, and the retrograde guide wire W is expanded through the expanded aperture 211. Can be taken into the mesh member 21. On the other hand, when the proximal end portion of the core wire 41 is pushed into the hollow shaft 11 toward the distal end side, the mesh member 21 is reduced in diameter and can easily move in the body cavity.

As a kind of wire which constitutes mesh member 21, for example, a single wire, a twisted wire, and a combination of these can be adopted. Examples of the stranded wire include a stranded wire bundled with a plurality of strands and twisted in a spiral shape, a stranded wire having a plurality of side wires twisted around a core wire, and the like. Among these, the type of the wire is preferably a stranded wire. Thereby, the softness | flexibility (deformability) of the mesh member 21 can be improved, and it can expand / contract more smoothly and reliably.

Examples of the material of the wire constituting the mesh member 21 include metal materials such as stainless steel such as SUS304, nickel titanium alloy, and cobalt chromium alloy; resin materials such as polyamide, polyester, polyacrylate, and polyetheretherketone. It is done. Among these, a metal material is preferable from the viewpoint of improving strength and flexibility. In addition, when the mesh member 21 is comprised by the several strand, these strands may be formed with the same material and may be formed with a different material.

The distal tip 31 smoothly advances the catheter 1 in the body cavity. The tip chip 31 is joined to the tip of the mesh member 21. Specifically, the distal tip 31 includes a through hole 311 for inserting a guide wire (for example, an antegrade guide wire (not shown)), and is formed to have a substantially sharp shape toward the distal end side. be able to. In addition, the distal end portion of each element wire constituting the mesh member 21 is embedded in the proximal end portion of the distal tip 31.

It is preferable that the material constituting the tip 31 has flexibility so that the impact on the body cavity or the like can be reduced. Examples of such materials include resin materials such as polyurethane and polyurethane elastomer.

The core wire 41 extends through the inside of the mesh member 21 and the hollow shaft 11 so that the distal end is joined to the distal end tip 31 and the proximal end is located on the proximal end side with respect to the proximal end of the hollow shaft 11. Specifically, for example, the core wire 41 has a distal end fixed to the proximal end of the distal end tip 31 inside the mesh member 21 by welding or the like, and the inner side of the mesh member 21, the lumen 11c of the distal end side shaft 11a, the proximal end The base end is exposed to the outside of the connector 61 through the lumen 11 d of the side shaft 11 b and the through hole 611 of the connector 61. The mesh member 21 is expanded and contracted in the radial direction by operating the proximal end portion of the core wire 41 and moving forward and backward along the axial direction of the hollow shaft 11.

It is preferable that the material constituting the core wire 41 has sufficient rigidity and tensile strength from the viewpoint of reliably expanding and contracting the mesh member 21 and preventing the core wire 41 itself from being cut. Examples of such a material include metal materials such as stainless steel such as SUS304, nickel titanium alloy, and cobalt chromium alloy.

The magnet 51, for example, pulls the retrograde guide wire W by a magnetic force and guides it to the lumen 11c of the hollow shaft 11 through the inside of the mesh member 21. When the magnet member 51 is expanded in the radial direction of the mesh member 21, a portion of the core wire 41 located inside the mesh member 21 (a portion of the core wire 41 surrounded by the mesh member 21 in the axial direction of the catheter 1). Is provided.

Here, the form of the magnet 51 may be one place of the core wire 41 or a plurality of places. Moreover, the magnet 51 and the core wire 41 may be separate from each other or may be integrated. When the magnet 51 and the core wire 41 are separate bodies, the magnet 51 can be formed so as to surround the core wire 41, for example. On the other hand, when the magnet 51 and the core wire 41 are integrated, the magnet 51 may magnetize a part of the core wire 41 and use the magnetized portion as the magnet 51.

Specifically, the form of the magnet 51 is, for example, an ellipsoidal magnet 511 (see FIG. 4A), a columnar magnet 512 (see FIG. 4B), a spherical magnet 513 (see FIG. 4C), or toward the tip side. The cone-shaped magnet 514 (see FIG. 4D) that gradually decreases in diameter and the conical magnet 515 (see FIG. 4E) that gradually decreases in diameter toward the base end side, and two or more of these shaped magnets are combined

Magnets

516, 517, and 518 (see FIGS. 4F, 4G, and 4H), a magnet 519 (see FIG. 4I) that magnetizes the core wire itself, and the like can be employed.

In addition, it is preferable that the form of the magnet 51 described above has a larger outer diameter than the core wire 41. Examples of such a magnet 51 include a magnet that surrounds the core wire 41 (see, for example, FIGS. 4A to 4H). Thus, even when the retrograde guide wire W is at a position farther from the magnet 51 than the case where the magnet 51 has an outer diameter dimension larger than that of the core wire 41, the same outer diameter dimension, The retrograde guidewire W can be pulled.

The type of the magnet 51 is not particularly limited as long as the retrograde guide wire W can be attracted by magnetic force and guided to the lumen 11c of the hollow shaft 11. For example, an alnico magnet, a ferrite magnet, a samarium cobalt magnet, a neodymium magnet, a praseodymium Magnets, neodymium / iron / boron magnets, samarium nitrogen iron magnets, cerium / cobalt magnets, platinum magnets and the like can be used.

As a material constituting the retrograde guide wire W, the magnet 51 allows the surgeon to reliably reach the inside of the mesh member 21 through the bent blood vessel of the body cavity. From the viewpoint of being attracted to the surface, it is preferable to have sufficient rigidity, elasticity, and magnetism. Examples of such materials include metal materials such as ferritic stainless steel such as SUS430, martensitic stainless steel such as SUS403, and austenitic stainless steel such as SUS304 that has become magnetic by cold working. It is done.

The magnet 51 is also preferably opaque to radiation. As such a magnet 51, for example, a permanent magnet containing a radiopaque element can be employed. When the magnet itself does not contain a radiopaque element, the magnet 51 may be a combination of the magnet itself and a substance containing a radiopaque element (hereinafter also referred to as “radiopaque substance”). For example, a magnet formed by mixing a permanent magnet and a radiopaque substance, a magnet formed by coating a radiopaque substance on the surface of the permanent magnet, and the like can be employed. Examples of the radiopaque material include gold, platinum, tungsten, and alloys containing these elements (eg, platinum-nickel alloys).

Thus, since the magnet 51 is opaque to radiation, the position of the magnet 51 in the body cavity can be visually recognized using the radiation transmission image, and the procedure can be performed smoothly. When the magnet 51 is opaque to radiation, the end of the retrograde guide wire W is opaque to the radio 51 so that the positional relationship between the magnet 51 and the retrograde guide wire W can be accurately grasped. A portion 91 is preferably provided (see FIG. 3). Examples of the radiopaque portion 91 include a member containing a radiopaque substance bonded to the end portion of the retrograde guidewire W.

The connector 61 is a member for the operator to hold the catheter 1. The connector 61 is connected to the base end portion of the hollow shaft 11, and a through hole 611 communicating with the lumen 11 d of the hollow shaft 11 and the base end of the through hole 611 so that the core wire 41 is exposed to the outside. And an opening 612 formed. The form of the connector 61 is not particularly limited as long as the effect of the present invention is not impaired.

The induction film 71 is a film-like member whose base end is located at the base end of the mesh member 21 and covers a part of the mesh member 21. According to this guide film 71, for example, the retrograde guide wire W received through the mesh 211 of the mesh member 21 is smoothly guided toward the opening 11e of the hollow shaft 11 (opening at the tip of the tip side shaft 11a). Can do. Specifically, the guide membrane 71 has, for example, a distal end located between the proximal end of the distal tip 31 and the distal end of the hollow shaft 11, and a proximal end located at the distal end of the hollow shaft 11. A part of the guide film 71 may be bonded to the mesh member 21. For example, the tip part of the guide film 71 (for example, the outer periphery of the tip of the guide film 71), the base end part, and / or the center part are joined. can do. The guiding membrane 71 of the present embodiment has a distal end located substantially at the center in the axial direction of the mesh member 21 and a proximal end located at the distal end of the hollow shaft 11 so that the strands of the mesh member 21 are bridged. The induction film 71 and the mesh member 21 are joined to each other.

Examples of the material constituting the induction film 71 include polyethylene, polyurethane, polyamide, polyamide elastomer, polyolefin, polyester, polyester elastomer, and the like. Among these, the material is preferably polyurethane from the viewpoint of improving the sliding property of the surface. The induction film 71 can be formed using, for example, a dip method for bridging the strands of the mesh member 21, a fusion method for fusing the open end of a funnel-shaped film to the mesh member 21, or the like.

Further, when the catheter 1 includes the guide membrane 71, the magnet 51 is more proximal than the tip of the guide membrane 71 or the tip of the guide membrane 71 in the core wire 41 when the mesh member 21 is expanded in the radial direction. It is preferable that it is provided in the part located in the side. Specifically, as shown in FIG. 2, the magnet 51 is configured such that, for example, when the mesh member 21 is expanded (expanded) in the radial direction, the position of the magnet 51 in the axial direction of the catheter 1 is It is preferable that the distance between the distal end 71 and the proximal end of the guide film 71 is set. Thereby, the retrograde guide wire W can be guided into the guide film 71 by the magnet 51, and the retrograde guide wire W can be received more reliably.

Further, when the catheter 1 includes the guide film 71, the guide film 71 is preferably provided with a radiopaque portion including a radiopaque substance at the distal end portion of the guide film 71. Specifically, for example, a band-shaped radiopaque portion 81 formed on the outer peripheral edge of the distal end portion of the guide film 71 can be employed as the radiopaque portion (see catheter 1m1 in FIG. 5). ). In addition, as a radiopaque substance used for the radiopaque part 81, the thing similar to what was shown by description of the magnet 51, etc. can be employ | adopted. Thereby, it is possible to visually recognize the development of the guide film 71 using the radiation transmission image. In addition, when the magnet 51 is opaque to the radiation, the positional relationship between the magnet 51 and the guide film 71 is accurately determined. Since it can be grasped (refer to Drawing 6), retrograde guide wire W can be received more certainly and smoothly.

Next, a mode in which the retrograde guidewire W is received using the catheter 1 will be described. Here, a procedure for allowing the retrograde guidewire W to pass through a site where an obstruction in the blood vessel exists (hereinafter also referred to as “occlusion site”) will be described.

First, after the antegrade guidewire is inserted into the blood vessel, the antegrade guidewire is pushed along the blood vessel to the occlusion site. Next, after the distal end of the antegrade guide wire reaches the occlusion site, the proximal end of the antegrade guide wire is inserted into the through hole 311 of the distal tip 31, and the distal end of the catheter 1 is guided using the antegrade guide wire as a guide. Is pushed to the occlusion site in the blood vessel. At this time, the catheter 1 is inserted into the blood vessel in a state where the mesh member 21 is reduced in diameter, and the reduced diameter is maintained until the distal end of the catheter 1 reaches the occlusion site.

Next, after the distal end of the catheter 1 reaches the occlusion site, the antegrade guidewire is pulled out of the catheter 1 by pulling the antegrade guidewire toward the proximal end side with respect to the catheter 1. Next, by pulling the end portion of the core wire 41 exposed to the outside of the connector 61 toward the proximal end side, the distance between the distal end of the mesh member 21 and the distal end of the hollow shaft 11 is narrowed. Outward deformation (bulging) outwards to expand the diameter. At this time, since the mesh 211 is expanded with the diameter of the mesh member 21, the retrograde guide wire W is easily received. In the present embodiment, the leading end of the induction film 71 is joined to the substantially central portion of the mesh member 21 in the axial direction. Therefore, the induction film 71 is also expanded in diameter following the increase in diameter of the mesh member 21, and the induction film 71. Becomes a funnel shape as a whole (see FIG. 2).

Next, the retrograde guide wire W coming from the distal end side is received by the catheter 1. As a path that the retrograde guide wire W is directed to, for example, a pseudo-cavity in the blood vessel wall surrounding the occlusion site, a through-hole penetrating the occlusion site, and the like are assumed. W may be sufficient. The retrograde guide wire W is received in the space inside the mesh member 21 through the aperture 211 of the expanded mesh member 21, and then received in the hollow shaft 11 through the opening 11e, and further, the opening 11f. It is delivered to the outside of the catheter 1 through. Next, the retrograde guidewire W delivered from the opening 11f passes through the blood vessel, and then the end is delivered out of the body. As a result, it is possible to create a state in which the retrograde guidewire W passes through the obstruction site and both end portions of the retrograde guidewire W are exposed to the outside of the body.

As described above, since the catheter 1 has the above-described configuration, the retrograde guide wire W can be attracted by a magnetic force and guided to the lumen 11c of the hollow shaft 11 through the inside of the mesh member 21. Can accept W reliably.

Further, since the catheter 1 can receive the retrograde guidewire W and can guide the end portion outside the body, it can be suitably used as a medical instrument combined with the retrograde guidewire W.

In addition, this invention is not limited to the structure of embodiment mentioned above, is shown by the claim, and intends that all the changes within the meaning and range equivalent to a claim are included. Is done. 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, in the above-described embodiment, the catheter 1 including the guide membrane 71 has been described. However, for example, as shown in FIG. 7, the catheter 2 may not include the guide membrane. Even in the catheter 2 that does not include such a guide membrane, the retrograde guide wire W can be attracted by a magnetic force, and the retrograde guide wire W can be guided to the lumen 11c of the hollow shaft 11 (see FIG. 8). reference).

1, 2 Catheter 11 Hollow shaft 21 Mesh member 31 Tip tip 41 Core wire 51 Magnet 71 Guide membrane

Claims

A hollow shaft;
A tubular mesh member joined to the tip of the hollow shaft and expandable / contractable in the radial direction;
A tip chip joined to the tip of the mesh member;
A core wire extending through the mesh member and the interior of the hollow shaft such that a distal end is joined to the distal tip, and a proximal end is located on a proximal side of the proximal end of the hollow shaft;
With
When the mesh member is expanded in the radial direction, a magnet is provided in a portion of the core wire located inside the mesh member.
catheter.
The magnet has a larger outer diameter than the core wire.
The catheter according to claim 1.
The magnet is opaque to radiation;
The catheter according to any one of claims 1 and 2.
A base end is located at the base end of the mesh member and includes a guide membrane covering a part of the mesh member;
The magnet is provided in a portion of the core wire that is located on the proximal side of the distal end of the induction membrane or the distal end of the induction membrane when the mesh member is expanded in the radial direction.
The catheter according to any one of claims 1 to 3.