JP2020062319A - catheter - Google Patents

Abstract

To provide a catheter, with which it is possible to easily confirm that, for instance, a retrograde guide wire is inserted into a hollow shaft.SOLUTION: A catheter 1 comprises: a hollow shaft 11; a tubular mesh member 21 whose base end is joined to a distal end of the hollow shaft 11 and which is configured to expand or contract in a radial direction; a distal end tip 31 joined to a distal end of the mesh member 21; a core wire 41 whose distal end is joined to the distal end tip 31 and which extends inside the mesh member 21 and the hollow shaft 11 so that a base end of the core wire 41 is positioned on a base end side with respect to a base end of the hollow shaft 11; and at least two radiopaque markers 71 which are provided for the hollow shaft 11 integrally or separately, and are spaced apart from each other in a long axis direction of the hollow shaft 11.SELECTED DRAWING: Figure 1

Description

  The present invention relates to catheters.

  As a procedure to improve blood flow by removing blockages that block blood vessels such as chronic total occlusion (CTO), a procedure to insert a retrograde guide wire from the opposite side (peripheral side) of CTO is known. It is known (see Non-Patent Document 1, for example).

  In such a procedure, for example, a catheter provided with a mesh member having a radiopaque material and a hollow shaft continuous with the mesh member is used, and the retrograde guide wire that has passed through the CTO has the above radiopaque property. The permeable material is used as a clue to be trapped in the mesh member and then guided to the hollow shaft.

Shinsuke Nanto, “Revised Edition: Basics and Tips for Securely Wearing PCI,” Yodosha, February 25, 2016, p. 222-227

  However, in the conventional catheter as described above, the radiopaque material is used only for the mesh member, and although the insertion of the retrograde guidewire into the mesh member can be confirmed, the retrograde guidewire is used for the hollow shaft. There was a problem that it was difficult to confirm whether or not it entered.

  The present invention has been made based on the above circumstances, and an object thereof is to provide a catheter capable of easily confirming that a retrograde guide wire has been inserted into a hollow shaft. is there.

Some aspects of the disclosure include
(1) a hollow shaft,
A proximal end is joined to the distal end of the hollow shaft, and a tubular mesh member that can be expanded and contracted in the radial direction,
A tip chip joined to the tip of the mesh member,
The distal end is joined to the distal end of the mesh member and / or the distal end tip, and extends through the inside of the mesh member and the hollow shaft so that the proximal end is located closer to the proximal end side than the proximal end of the hollow shaft. A core wire,
A catheter provided integrally with or separately from the hollow shaft, and comprising at least two radiopaque markers that are spaced apart in the longitudinal direction of the hollow shaft,
(2) The catheter according to (1), in which the interval between the adjacent markers is larger than the outer diameter of the hollow shaft,
(3) The most distal marker among the markers is the distal marker,
The inner diameter of the hollow shaft between the distal end side marker and the proximal end side marker adjacent to the distal end side marker is smaller than the inner diameter of the hollow shaft at the distal end of the distal end side marker (1) or (2). The catheter described in (4), wherein the most distal marker among the markers is the distal marker,
The catheter according to any one of (1) to (3), wherein the tip of the tip-side marker is aligned with the tip of the hollow shaft in the long axis direction.

  In the present specification, the “tip side” means the direction along the major axis direction of the catheter and the direction in which the mesh member is located with respect to the hollow shaft. Further, the “proximal end side” means a direction along the major axis direction of the catheter, which is opposite to the distal end side. Further, the “tip” refers to the end on the tip side of any member or site forming the catheter, and the “proximal end” refers to the end on the base end side of any member or site forming the catheter. .

  INDUSTRIAL APPLICABILITY The present invention can provide a catheter capable of easily confirming that a retrograde guide wire has been inserted into a hollow shaft.

It is a partial notch schematic side view which shows the whole 1st Embodiment of this invention, and is a figure which shows the state which the mesh member reduced in diameter. It is a partially expanded schematic perspective view of FIG. It is a partial notch schematic side view which shows the suitable example of 1st Embodiment. It is a partially cutaway schematic side view which shows the state where the diameter of the mesh member of FIG. 1 was expanded and the retrograde guide wire was inserted. FIG. 5 is a partially enlarged schematic perspective view of FIG. 4. It is a partially expanded schematic perspective view which shows the modification of 1st Embodiment. It is a partial notch schematic side view which shows the whole 2nd Embodiment of this invention. It is a schematic sectional drawing showing the A section of FIG. It is a partially notched schematic side view which shows the modification of 2nd Embodiment. It is a schematic sectional drawing showing the B section of FIG. It is a partially cutaway schematic side view which shows the other aspect of the catheter of this invention. It is a partially cutaway schematic side view which shows the other aspect of the catheter of this invention.

  Hereinafter, the first and second embodiments 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" refers to a guide wire that is pushed forward to a surgical site such as an occlusion site in a blood vessel prior to insertion of a catheter among the guide wires. The term “guide wire” means a guide wire of the guide wire, which comes into the blood vessel from the distal end side of the catheter.

  Further, in the following embodiments, a marker located closest to the tip side of the markers (hereinafter, also referred to as “tip side marker”) and a marker located closer to the base side than the tip side marker and adjacent to the tip side marker. An explanation will be given by exemplifying a catheter provided with two markers, a matching marker (hereinafter, also referred to as “proximal marker”).

[First Embodiment]
FIG. 1 is a partially cutaway schematic side view showing the entire first embodiment of the present invention, and is a view showing a state in which a mesh member has a reduced diameter. As shown in FIG. 1, the catheter 1 is roughly composed of a hollow shaft 11, a mesh member 21, a guiding film 31, a tip 41, a core wire 51, a connector 61, and a marker 71. ing.

  The hollow shaft 11 is a hollow shaft. The hollow shaft 11 can be configured by, for example, the distal shaft 111, the proximal shaft 112, and the guide wire port 113. The tip side shaft 111 has a tip connected (fixed) to a base end of a mesh member 21 described later, and has a lumen 111a inside. The base end side shaft 112 has a distal end connected (fixed) to a base end of the front end side shaft 111 and a base end connected to a front end of a connector 61 described later, and has a lumen 112a therein. The lumen 111a and the lumen 112a communicate with each other, and for example, the core wire 51 and the like are inserted therein. The guide wire port 113 is an opening that communicates the inside of the hollow shaft 11 with the outside of the catheter 1, and is provided at the connecting portion between the distal shaft 111 and the proximal shaft 112. The guide wire port 113, for example, inserts the retrograde guide wire W2 (see FIG. 4) received by the distal shaft 111 and sends it out.

  As a material for forming the hollow shaft 11, it is preferable that the hollow shaft 11 has antithrombogenicity, flexibility and biocompatibility since the hollow shaft 11 is inserted into a blood vessel. Examples of such a material include resin materials such as polyamide resin, polyolefin resin, polyester resin, polyurethane resin, silicone resin, and fluororesin for the distal shaft 111. Examples of the proximal shaft 112 include stainless steel such as SUS304, nickel titanium alloy, cobalt chromium alloy, and the like. As a result, for example, the distal shaft 111 can have particularly improved flexibility, and the proximal shaft 112 can have particularly improved pushability.

  The mesh member 21 is a tubular member whose proximal end is joined (fixed) to the distal end of the hollow shaft 11 and which can be expanded and contracted in the radial direction. Specifically, the mesh member 21 can be formed by, for example, knitting a single wire or a plurality of wires (stranded wire) 21a in a lattice shape. The mesh member 21 expands in diameter (expands radially outward) by pulling a core wire 51, which will be described later, toward the proximal end side, and the retrograde guide wire W2 is formed through the openings 21b of the expanded mesh member 21. Into the catheter 1.

  As a method of joining the mesh member 21 and the hollow shaft 11, for example, a method of embedding each of the wires 21a located at the proximal end of the mesh member 21 in the distal end of the hollow shaft 11 by welding or the like can be adopted. it can.

  As a material forming the strand 21a, for example, a resin material, a metal material, or the like can be adopted. Examples of the resin material include polyamide, polyester, polyacrylate, and polyether ether ketone. Examples of the metal material include stainless steel such as SUS304, nickel titanium alloy, and cobalt chrome alloy. Among these, a metal material is preferable from the viewpoint of improving strength and flexibility. When the strand 21a is formed of a plurality of strands, the plurality of strands 21a may be formed of the same material or different materials.

  Further, the material forming the strands 21a may include a radiopaque material from the viewpoint of improving the visibility of the mesh member 21 under radioscopy. Examples of the radiopaque material include gold, platinum, tungsten, and alloys containing these elements (for example, platinum-nickel alloy). 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 film 31 is a film-shaped member that covers a part of the mesh member 21. The guide film 31 can be formed, for example, such that the tip end is located substantially at the center of the mesh member 21 in the major axis direction and the base end is located at the tip end of the hollow shaft 11. At least a part of the guide film 31 is joined to the mesh member 21, and for example, the guide film 31 expands into a funnel shape in accordance with the expansion of the mesh member 21.

  Examples of the material forming the induction film 31 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. As a method of forming the induction film 31, for example, the material forming the induction film 31 is heated and melted, and the mesh member 21 is immersed in the melted material to bridge the wires 21a (close the openings 21b). It is possible to employ a method of welding, a method of welding or adhering the opening peripheral edge of the funnel-shaped film to the mesh member 21 with a mesh or the like.

  The tip 41 is a member joined to the tip of the mesh member 21. Specifically, for example, the distal end tip 41 is formed so that the distal end portion has a substantially pointed shape rounded toward the distal end side so that the catheter 1 can easily advance in a blood vessel, and the distal end tip 41 is provided at the distal end. It has a through hole 41a having an opening 41b. The tip end 41 is joined (fixed) to the tip end of the mesh member 21 or the like at the base end.

  As a joining method between the tip 41 and the mesh member 21, for example, a method of embedding each of the wires 21a located at the tip of the mesh member 21 in the base end of the tip 41 by welding or the like can be adopted. it can.

  It is preferable that the material forming the distal end tip 41 has flexibility so that the impact on the body cavity or the like can be mitigated together with the antithrombogenic and biocompatible body. Examples of such a material include resin materials such as polyurethane and polyurethane elastomer.

  The core wire 51 has a distal end joined (fixed) to the distal end of the mesh member 21 and / or the distal end tip 41, and the proximal end is located closer to the proximal end side than the proximal end of the hollow shaft 11 is. It extends through the inside of 11. Specifically, for example, the tip of the core wire 51 is fixed to the tip 41 by welding, and the space inside the mesh member 21, the lumens 111a and 112a of the hollow shaft 11, and the through hole 61a of the connector 61 are provided. Can be disposed so that the proximal end is exposed to the outside of the catheter 1 through the opening 61b. The mesh member 21 is expanded and contracted by operating (advancing and retracting) the core wire 51 in the long axis direction.

  The material forming the core wire 51 preferably has sufficient tensile strength and rigidity from the viewpoint of preventing the core wire 51 itself from being cut and reliably expanding and contracting the mesh member 21. As such a material, for example, stainless steel such as SUS304, a metal material such as a nickel titanium alloy, and a cobalt chrome alloy can be cited.

  The connector 61 is a member that an operator holds the catheter 1. Specifically, the connector 61 has, for example, a through hole 61a communicating with the lumen 112a and an opening 61b located at the base end of the through hole 61a. The external shape of the connector 61 may be any shape as long as it can be easily grasped by the operator.

  The marker 71 is a radiopaque member that is provided integrally with or separately from the hollow shaft 11, and is provided at at least two portions that are separated from each other in the long axis direction of the hollow shaft 11. Specifically, the marker 71 of the catheter 1 is composed of a distal end side marker 71a and a proximal end side marker 71b. The distal end side marker 71a and the proximal end side marker 71b are separately formed on the outer peripheral surface of the distal end side shaft 111, for example, and are formed in a thin film shape in the entire circumferential direction, as shown in FIG. be able to.

  The material forming the marker 71 may include a radiopaque material. For example, a radiopaque material is used alone, a radiopaque material and a non-radiopaque material. It is possible to employ a combination of and. Examples of the radiopaque material include gold, platinum, tungsten, and alloys containing these elements (for example, platinum nickel alloy). Examples of the material that is not radiopaque include an adhesive for fixing the radiopaque material to the hollow shaft 11.

  In the catheter 1, the tip of the tip-side marker preferably coincides with the tip of the hollow shaft in the long axis direction. As such a catheter, for example, a catheter 1m1 (see FIG. 3) including a distal end side marker 71am1 formed over the entire outer circumferential surface of the distal end portion of the hollow shaft 11 in the circumferential direction may be exemplified. it can.

  In this way, the tip of the tip-side marker 71am1 coincides with the tip of the hollow shaft 11 in the long axis direction, so that, for example, under radioscopy, the positional relationship between the tip of the hollow shaft 11 and the retrograde guide wire W2 is accurate. Therefore, the retrograde guide wire W2 can be easily inserted into the hollow shaft 11.

  Further, in the catheter 1, it is also preferable that the distance between the adjacent markers 71 (the distal end side marker 71 a and the proximal end side marker 71 b) is larger than the outer diameter of the hollow shaft 11. Specifically, like the catheter 1, for example, the length m (interval m) between the proximal end of the distal end side marker 71a and the distal end of the proximal end side marker 71b is larger than the outer diameter od1 of the hollow shaft 11. (M> od1) can be exemplified (see FIG. 1).

  In this way, since the distance between the adjacent markers 71 is larger than the outer diameter of the hollow shaft 11, it is possible to prevent the adjacent markers 71 from appearing to overlap with each other under radioscopy, and the retrograde guide wire W2 is provided. It is possible to more accurately grasp the positional relationship with the hollow shaft 11.

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

  First, the antegrade guide wire W1 (not shown) is inserted into, for example, a blood vessel, and then pushed 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 site, a balloon catheter (not shown) is inserted to the occluded site using the antegrade guide wire W1 as a guide, and the occluded site is expanded by expanding the diameter of the balloon. . After expanding the occluded site, the balloon is contracted to remove the balloon catheter from the blood vessel.

  Next, the proximal end of the antegrade guide wire W1 passes through the guide wire port 113 from the opening 41b at the distal end of the distal tip 41, the space inside the mesh member 21, the lumen 111a, and the guide wire port 113. The antegrade guide wire W1 is inserted through the catheter 1 so as to be exposed to the outside, and the distal end of the catheter 1 is pushed forward to the occluded site in the blood vessel by using the antegrade guide wire W1 as a guide. At this time, the catheter 1 is inserted into a blood vessel with the mesh member 21 having a reduced diameter, and the reduced diameter is maintained until the distal end 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 51 exposed to the outside of the connector 61 toward the proximal end side, the distance between the tip of the mesh member 21 and the tip of the hollow shaft 11 is narrowed, and as a result, the diameter of the mesh member 21 is increased (diameter). Bulge outward in the direction). At this time, in the present embodiment, since the tip of the guide film 31 is joined to the substantially central portion of the mesh member 21 in the long axis direction, the guide film 31 is expanded in diameter in accordance with the expansion of the mesh member 21. The membrane 31 has a funnel shape as a whole. Since the mesh openings 21b are expanded as the diameter of the mesh member 21 is expanded, the retrograde guide wire W2 is easily received. In addition, after the distal end of the catheter 1 reaches the occluded site along the antegrade guide wire W1, the mesh member 21 is expanded radially outward, and then the antegrade guide wire W1 is removed from the catheter 1. It may be pulled out.

  Next, as shown in FIG. 4, 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 21 through the openings 21b of the expanded mesh member 21, and then inserted into the distal shaft 111 through the opening 111b. At this time, the operator, under radioscopy, the positional relationship between the distal side marker 71a and the proximal side marker 71b and the retrograde guide wire W2 (for example, the retrograde guide wire W2 is the distal side marker 71a and the proximal side). It is possible to determine that the retrograde guide wire W2 has been inserted into the hollow shaft 11 by pushing the retrograde guide wire W2 while checking the positional relationship (crossing both the markers 71b) (see FIG. 5). After that, the retrograde guide wire W2 is delivered to the outside of the catheter 1 through the guide wire port 113, and then the end portion thereof is delivered to the outside of the body. Thereby, it is possible to create a state in which the retrograde guide wire W2 passes through the closed portion and both ends of the retrograde guide wire W2 are exposed outside the body.

  As described above, the catheter 1 is provided integrally with or separately from the hollow shaft 11, and the two radiopaque markers 71 (the distal side marker 71a and the proximal side) that are separated in the longitudinal direction of the hollow shaft 11. Since the marker 71b) is provided, for example, the positional relationship between the hollow shaft 11 and the retrograde guide wire W2 can be accurately grasped, and it is easy to insert the retrograde guide wire W2 into the hollow shaft 11. Can be confirmed.

  The hollow shaft 11 and the marker 71 may be integrated or separated in the catheter 1, for example, an annular marker 71m2 fitted on the outer peripheral surface of the hollow shaft 11 with an adhesive or the like. It may be a catheter 1m2 (see FIG. 6) provided (separate from the hollow shaft 11), a catheter (not shown) provided with a marker integrally provided on the hollow shaft, or the like.

[Second Embodiment]
FIG. 7 is a partially cutaway schematic side view showing the entire second embodiment of the present invention. As shown in FIG. 7, the catheter 2 is roughly composed of a hollow shaft 12, a mesh member 21, a guiding film 31, a tip 41, a core wire 51, a connector 61, and a marker 72. ing. The catheter 2 is different from that of the first embodiment in that the catheter 2 includes the hollow shaft 12 and the marker 72. Since the configurations of the mesh member 21, the guide film 31, the tip 41, the core wire 51, and the connector 61 are the same as those in the first embodiment, the same parts are designated by the same reference numerals, and detailed description thereof will be given. Is omitted. Further, the configuration other than the shapes of the hollow shaft 12 and the marker 72 is the same as that of the first embodiment, and therefore the description thereof is omitted.

  The hollow shaft 12 is a hollow shaft. The hollow shaft 12 can be configured by, for example, the distal shaft 121, the proximal shaft 122, and the guide wire port 123. The tip end side shaft 121 has a tip end connected (fixed) to the base end of the mesh member 21, and has a lumen 121a inside. The proximal end side shaft 122 has a distal end connected (fixed) to the proximal end of the distal end side shaft 121 and the proximal end to the distal end of the connector 61, and has a lumen 122a inside. The lumen 121a and the lumen 122a communicate with each other, and for example, the core wire 51 and the like are inserted therein. The guide wire port 123 is an opening that communicates the inside of the hollow shaft 12 with the outside of the catheter 2, and is provided at the connecting portion between the distal shaft 121 and the proximal shaft 122.

  The marker 72 is a radiopaque member that is provided integrally with or separately from the hollow shaft 12, and is provided at at least two portions that are separated from each other in the long axis direction of the hollow shaft 12. Specifically, the marker 72 of the catheter 2 is composed of a distal end side marker 72a and a proximal end side marker 72b. The distal end side marker 72a and the proximal end side marker 72b are, for example, separately formed on the outer peripheral surface of the distal end side shaft 121, and can be formed in a thin film shape over the entire circumferential direction.

  Here, as shown in FIG. 8, the hollow shaft 12 (the distal shaft 121) of the catheter 2 has a lumen 121a between the distal marker 72a and a proximal marker 72b adjacent to the distal marker 72a. Is smaller than the inner diameter of the lumen 121a at the tip of the tip-side marker 72a. Specifically, for example, in the distal shaft 121, a portion (inner cavity) in which the lumen 121a has the same inner diameter id1 over the long axis direction and a portion located closer to the distal end than this portion and having an inner diameter id1 And a portion (lumen) having a large inner diameter id2.

  Further, the distal-side shaft 121 is provided with a portion (inner cavity) in which, for example, the lumen 121a is located closer to the base end side than the portion having the inner diameter id1 and has an inner diameter id3 larger than the inner diameter id1 like the catheter 2. You may do it. In the present embodiment, a hollow having substantially the same thickness over the entire major axis direction and having a lumen 121a whose inner diameter changes linearly inside each of the distal end side marker 72a and the proximal end side marker 72b. The catheter 2 including the shaft 12 (the tip shaft 121) is illustrated.

  As described above, in the catheter 2, the inner diameter of the lumen 121a between the distal-side marker 72a and the proximal-side marker 72b is smaller than the inner diameter of the lumen 121a at the distal end of the distal-side marker 72a. The radial position of the retrograde guide wire W2 that has entered can be limited, and it can be more easily grasped that the retrograde guide wire W2 has entered the hollow shaft 12.

  In the catheter 2, the inner diameter of the hollow shaft 12 between the distal end side marker 72a and the proximal end side marker 72b may be smaller than the inner diameter of the hollow shaft 12 at the distal end of the distal end side marker 72a, for example, FIG. As shown in FIG. 10, the outer diameter of the hollow shaft 12m1 may be a catheter 2m1 having substantially the same diameter over the entire major axis direction.

  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, in the first and second embodiments, the hollow shafts 11 and 12 each have two markers (a distal marker 71a and a proximal marker 71b, and a distal marker 72a and a proximal marker 72b). 2 has been described, it is a catheter provided with three or more markers along the long axis direction of the hollow shaft (for example, the catheter 3 provided with three markers 73a, 73b, 73c is illustrated in FIG. 11). May be.

  Further, the catheter may be provided with an in-mesh hollow shaft that is connected to the distal end tip and protrudes toward the proximal end side in the space inside the mesh member. As a catheter provided with such a hollow shaft, as shown in FIG. 12, for example, there is a catheter 4 provided with an in-mesh hollow shaft 84 having a through hole 84a communicating with the through hole 41a of the tip 41. . A antegrade guide wire W1 (not shown), for example, can be inserted into the in-mesh hollow shaft 84.

  As the material forming the hollow mesh shaft 84, it is preferable that the hollow shaft 84 has the antithrombogenicity, flexibility, and biocompatibility because the hollow shaft 84 is inserted into a blood vessel. Examples of such a material include the same materials as those exemplified as the material forming the hollow shaft 11 in the first embodiment.

  Further, in the first and second embodiments, the catheters 1 and 2 in which the hollow shafts 11 and 12 have a distal shaft, a proximal shaft and a guide wire port have been described. It may be a catheter (not shown) (a so-called over-the-wire (OTW) type catheter) having a single hollow shaft having a single lumen extending therethrough.

  Further, in the above-described first and second embodiments, the catheters 1 and 2 having the markers 71 and 72 formed over the entire outer circumferential surface of the hollow shafts 11 and 12 in the circumferential direction have been described. For example, a catheter provided with a marker having a shape different from the above-described shape, such as a catheter (not shown) provided in a C shape along the circumferential direction on the outer peripheral surface of the hollow shaft, unless the effect of the present invention is impaired. May be

1, 2 Catheter 11, 12 Hollow shaft 21 Mesh member 41 Tip tip 51 Core wire 71, 72 Marker W1 Prograde guide wire W2 Retrograde guide wire

Claims (4)

A hollow shaft,
A proximal end is joined to the distal end of the hollow shaft, and a tubular mesh member that can be expanded and contracted in the radial direction,
A tip chip joined to the tip of the mesh member,
The distal end is joined to the distal end of the mesh member and / or the distal end tip, and extends through the inside of the mesh member and the hollow shaft so that the proximal end is located closer to the proximal end side than the proximal end of the hollow shaft. A core wire,
A catheter that is provided integrally with or separately from the hollow shaft and that has at least two radiopaque markers that are spaced apart in the longitudinal direction of the hollow shaft.   The catheter according to claim 1, wherein the interval between the adjacent markers is larger than the outer diameter of the hollow shaft. The most distal marker among the markers is the distal marker,
The inner diameter of the hollow shaft between the distal end side marker and the proximal end side marker adjacent to the distal end side marker is smaller than the inner diameter of the hollow shaft at the distal end of the distal end side marker. The described catheter. The most distal marker among the markers is the distal marker,
The catheter according to any one of claims 1 to 3, wherein the tip of the tip-side marker coincides with the tip of the hollow shaft in the long axis direction.

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