Catheter

Abstract

To improve stretch resistance of a catheter shaft.SOLUTION: A catheter includes a cylindrical shaft, a first reinforcement body and a second reinforcement body. The first reinforcement body is composed of a plurality of element wires spirally wound around the shaft. The second reinforcement body is composed of at least one element wire that is spirally wound around the shaft to overlap the first reinforcement body in a shaft's radial direction. At a first overlapping part to be a part of a plurality of overlapping parts of the first reinforcement body and the second reinforcement body, the first reinforcement body is located inside the second reinforcement body. At a second overlapping part to be another part of the plurality of overlapping parts, the first reinforcement body is located outside the second reinforcement body.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The technology disclosed in this specification relates to a catheter.

Background Art

[0002] A catheter is a long medical device that is inserted into a living body lumen such as a blood vessel and is used to diagnose or treat the inside of the living body lumen. The catheter includes a cylindrical shaft and a reinforcing member that reinforces the shaft. As the reinforcing member, for example, a coil body wound spirally around the shaft is used (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When a catheter is used, the shaft may extend. For example, when the catheter advances in a bent blood vessel, the inner lumen of the shaft becomes narrow due to external pressure or the like, and when an object (for example, an embolization coil for occluding an aneurysm or a highly viscous embolization substance) passes through the thus-narrowed lumen, the shaft may extend due to the resistance between the object and the surface of the lumen. Further, after the catheter enters a bent portion or an occluded portion in the blood vessel and is pulled back toward the proximal end side, the shaft may extend.

[0005] If the shaft stretches, there is a risk of it breaking. Also, if the shaft stretches, the lumen of the shaft narrows, which may cause concomitant devices passing through the lumen (e.g., guidewires or microcatheters) to get stuck, or hinder the smooth flow of fluids in the lumen (e.g., embolic materials for sealing aneurysms or expansion media for expanding balloon catheters). Furthermore, if the shaft stretches, the position of the markers at the tip of the shaft and the spacing between multiple markers change, which may reduce the accuracy of positioning for administering objects based on the marker positions (e.g., administering embolic materials to aneurysms). For this reason, it is preferable to improve the stretch resistance of the shaft in catheters.

[0006] Conventional catheters use simple coils as reinforcing elements to strengthen the shaft. However, when the shaft attempts to stretch, the reinforcing elements stretch or shift position, which prevents them from adequately improving the shaft's elongation resistance.

[0007] This specification discloses a technology capable of solving the above-mentioned problems. [Means for solving the problem]

[0008] (1) The catheter disclosed herein comprises a tubular shaft, a first reinforcing member, and a second reinforcing member. The first reinforcing member is composed of a plurality of strands spirally wound around the shaft. The second reinforcing member is composed of at least one strand spirally wound around the shaft so as to overlap with the first reinforcing member in the radial direction of the shaft. In a first overlapping area, which is part of a plurality of overlapping areas between the first and second reinforcing members, the first reinforcing member is located radially inward of the shaft than the second reinforcing member. In a second overlapping area, which is another part of the plurality of overlapping areas, the first reinforcing member is located radially outward of the shaft than the second reinforcing member.

[0009] In this catheter, there is a mixture of overlapping areas: a first overlapping area where the first reinforcing element is located inside the second reinforcing element, and a second overlapping area where the first reinforcing element is located outside the second reinforcing element. As a result, the first and second reinforcing elements constrain each other. Therefore, with this catheter, when the shaft attempts to stretch, the first and second reinforcing elements restrain each other, suppressing stretching and displacement, and the elongation resistance of the shaft can be sufficiently improved by the first and second reinforcing elements.

[0010] (2) In the catheter described above, the first overlapping portion and the second overlapping portion may be arranged regularly along the longitudinal direction of the shaft in at least some of the overlapping portions. By adopting this configuration, the first reinforcing body and the second reinforcing body firmly restrain each other, thereby further effectively improving the elongation resistance of the shaft.

[0011] (3) In the catheter described above, at least some of the overlapping portions may be configured such that the first overlapping portion and the second overlapping portion are alternately arranged along the longitudinal direction of the shaft. By adopting this configuration, the first reinforcing body and the second reinforcing body further restrain each other, thereby extremely effectively improving the elongation resistance of the shaft.

[0012] (4) In the catheter described above, the number of strands constituting the second reinforcing body may be less than the number of strands constituting the first reinforcing body. By adopting this configuration, it is possible to improve the elongation resistance of the shaft while suppressing the reduction in shaft flexibility due to the presence of the second reinforcing body.

[0013] (5) In the catheter described above, the winding direction of the second reinforcing member and the winding direction of the first reinforcing member may be in opposite directions. In this configuration, the number of overlapping points between the first and second reinforcing members can be increased compared to the configuration in which the winding direction of the second reinforcing member and the winding direction of the first reinforcing member are in the same direction. Therefore, by adopting this configuration, the elongation resistance of the shaft can be effectively improved by further strengthening the restraint between the first and second reinforcing members.

[0014] Furthermore, the technologies disclosed herein can be implemented in various forms, for example, in the form of a catheter, a method for manufacturing a catheter, and so on. [Brief explanation of the drawing]

[0015] [Figure 1] This diagram schematically shows the side view of the catheter 100 of this embodiment. [Figure 2] This is an explanatory diagram illustrating the cross-sectional structure of a portion of catheter 100 (part X1 in Figure 1). [Figure 3] This is an explanatory diagram illustrating the lateral configuration of a portion of catheter 100 (part X1 in Figure 1). [Figure 4] This diagram schematically shows the configuration of the first reinforcing body 21 and the second reinforcing body 22 in the catheter 100 of this embodiment. [Figure 5] A schematic diagram showing the configuration of the first reinforcement 21 and the second reinforcement 22 in the catheter 100X1 of the first comparative example. [Figure 6] A schematic diagram showing the configuration of the first reinforcement 21 and the second reinforcement 22 in the catheter 100X2 of the second comparative example. [Modes for carrying out the invention]

[0016] A. Embodiments: A-1. Components of Catheter 100: FIG. 1 is an explanatory diagram schematically showing a side configuration of the catheter 100 of the present embodiment, FIG. 2 is an explanatory diagram schematically showing a cross-sectional configuration of a part (X1 part in FIG. 1) of the catheter 100, and FIG. 3 is an explanatory diagram schematically showing a side configuration of a part (X1 part in FIG. 1) of the catheter 100.

[0017] Each figure shows XYZ axes orthogonal to each other. In the catheter 100, the positive Z-axis side is the tip side (distal side) inserted into the body, and the negative Z-axis side is the proximal side (proximal side) operated by a technician such as a doctor. In each figure, a part of the configuration of the catheter 100 is appropriately enlarged or not shown. Also, in each figure, the central axis Ax of the catheter 100 is shown in a substantially straight line parallel to the Z-axis direction, but the catheter 100 has flexibility enough to be curved. In this specification, for the catheter 100 and each of its constituent parts, the end on the tip side is referred to as the "tip", the tip and its vicinity are referred to as the "tip part", the end on the proximal side is referred to as the "proximal end", and the proximal end and its vicinity are referred to as the "proximal part".

[0018] The catheter 100 is a long medical device inserted into a living body lumen such as a vascular system, a lymphatic system, a biliary system, a urinary tract system, a respiratory tract system, a digestive organ system, a secretory gland, and a reproductive organ, and is used for diagnosing or treating within the living body lumen. The catheter 100 includes a shaft 10, a tip-side reinforcement 20, a proximal-side reinforcement 30, and a connector 90.

[0019] The shaft 10 is a cylindrical elongated member extending along the central axis Ax. An inner cavity 10M (Fig. 2) is formed in the shaft 10, extending along the central axis Ax from the tip end to the base end of the shaft 10. The cross-sectional shape of the inner cavity 10M can take any shape, for example, it is substantially circular. The inner cavity 10M of the shaft 10 is used to allow a combined device (for example, a guide wire, a microcatheter, etc.) or a fluid (for example, an embolization substance for occluding an aneurysm, an expansion medium for expanding a balloon catheter, etc.) to pass through. The outer diameter, inner diameter, and overall length of the shaft 10 can be arbitrarily set. The outer diameter of the shaft 10 is, for example, about 0.2 mm to 2.0 mm, and the overall length of the shaft 10 is, for example, about 1200 to 1800 mm.

[0020] As shown in Fig. 1, a first marker 18 and a second marker 19 are provided at the tip end portion of the shaft 10. The first marker 18 is disposed near the tip end of the shaft 10, and the second marker 19 is disposed at a position on the base end side by a predetermined distance (for example, about 30 mm) from the first marker 18. The first marker 18 and the second marker 19 are formed of a radiation-impermeable material. A technician such as a doctor can grasp the tip end position of the shaft 10 by visually recognizing the first marker 18 under radiation. Also, even if the first marker 18 cannot be visually recognized under radiation, the technician can grasp the tip end position of the shaft 10 based on the position where the second marker 19 is visually recognized and the above-mentioned predetermined distance.

[0021] As shown in Fig. 2, in this embodiment, the shaft 10 is composed of an inner layer 11 and an outer layer 12. The inner layer 11 is a cylindrical member that defines the inner cavity 10M, and the outer layer 12 is a cylindrical member that covers the outer periphery of the inner layer 11. In Fig. 3, for convenience of explanation, the illustration of the outer layer 12 is omitted.

[0022] The shaft 10 is preferably formed from a material that is antithrombotic, flexible, and biocompatible. Examples of materials for forming the shaft 10 include resin materials such as polyamide resin, polyolefin resin, polyester resin, polyurethane resin, silicone resin, and fluororesin. For example, the inner layer 11 is formed from polytetrafluoroethylene (PTFE), and the outer layer 12 is formed from a nylon-based elastomer resin. The composition of the shaft 10, including the forming material, may be uniform throughout its entire length, or it may differ in each part along the longitudinal direction.

[0023] As shown in Figure 1, the connector 90 constitutes the proximal end of the catheter 100 and is a component grasped by the operator. The connector 90 has, for example, a substantially cylindrical main body 91 and a plurality of fin portions 92 formed on the outer circumferential surface of the main body 91. The tip of the main body 91 is joined with the proximal end of the shaft 10 inserted into it. An opening (not shown) is formed at the proximal end of the main body 91, which communicates with the lumen 10M of the shaft 10. The connector 90 is made of a resin material such as polyamide, polypropylene, polycarbonate, polyacetal, or polyethersulfone.

[0024] The tip-side reinforcing member 20 is a member for reinforcing the shaft 10 and is embedded in the tip of the shaft 10. As shown in Figure 2, the tip-side reinforcing member 20 is wrapped around the outer circumferential surface of the inner layer 11 of the shaft 10 and covered by the outer layer 12 of the shaft 10. The configuration of the tip-side reinforcing member 20 will be described in detail later.

[0025] The base-side reinforcing member 30 is a member for reinforcing the shaft 10, and is embedded in the portion of the shaft 10 closer to the base end than the portion where the tip-side reinforcing member 20 is embedded. The base-side reinforcing member 30 can take any configuration, but for example, it may be a mesh-shaped cylindrical body (a so-called blade) made of wires woven into a mesh, or it may be a coil body made of wires wound in a spiral. The base-side reinforcing member 30 may be formed from, for example, a metal material or a resin material. For the sake of explanation, in Figure 1, the tip-side reinforcing member 20 and the base-side reinforcing member 30 embedded in the shaft 10 are shown with solid lines.

[0026] A-2. Detailed configuration of the tip-side reinforcing body 20: Next, the detailed configuration of the tip-side reinforcing body 20 will be described. As shown in Figures 2 and 3, the tip-side reinforcing body 20 has a first reinforcing body 21 and a second reinforcing body 22.

[0027] The first reinforcing body 21 is a coil body composed of multiple strands 21a spirally wound around the shaft 10. In this embodiment, the first reinforcing body 21 is composed of eight strands 21a. The eight strands 21a constituting the first reinforcing body 21 are arranged in contact with each other along the longitudinal direction of the shaft 10 (the direction parallel to the central axis Ax). The first reinforcing body 21 is formed by loosely winding these eight strands 21a in a spiral. The first reinforcing body 21 is wound in a Z-shape around the shaft 10.

[0028] The second reinforcing body 22 is a coil body composed of at least one strand 22a wound spirally around the shaft 10 so as to overlap with the first reinforcing body 21 in the radial direction of the shaft 10. In this embodiment, the second reinforcing body 22 is composed of one strand 22a. That is, the number of strands 22a constituting the second reinforcing body 22 is less than the number of strands 21a constituting the first reinforcing body 21. The second reinforcing body 22 is formed by loosely winding this one strand 22a spirally. The second reinforcing body 22 is wound in an S-shape around the shaft 10. That is, the winding direction of the second reinforcing body 22 and the winding direction of the first reinforcing body 21 are opposite.

[0029] The first reinforcing body 21 and the second reinforcing body 22 are formed from, for example, a metal material (stainless steel alloy such as SUS304, NiTi alloy, tungsten, etc.) or a resin material. Since the number of strands 22a constituting the second reinforcing body 22 is less than the number of strands 21a constituting the first reinforcing body 21, load tends to concentrate on the strands 22a constituting the second reinforcing body 22. Therefore, it is preferable that the tensile strength of the material forming the second reinforcing body 22 is higher than that of the material forming the first reinforcing body 21. The first reinforcing body 21 is formed from, for example, a NiTi alloy, and the second reinforcing body 22 is formed from, for example, tungsten.

[0030] Here, as shown in Figure 3, since both the first reinforcing body 21 and the second reinforcing body 22 are spiral coil bodies, they overlap radially in the shaft 10 at multiple overlapping points OP. At the first overlapping point OP1, which is part of the multiple overlapping points OP, the first reinforcing body 21 is located radially inward of the shaft 10 (hereinafter simply referred to as "inside") than the second reinforcing body 22. Conversely, at the second overlapping point OP2, which is another part of the multiple overlapping points OP, the first reinforcing body 21 is located radially outward of the shaft 10 (hereinafter simply referred to as "outside"). Thus, in the catheter 100 of this embodiment, there is a mixture of the first overlapping point OP1, where the first reinforcing body 21 is located inward of the second reinforcing body 22, and the second overlapping point OP2, where the first reinforcing body 21 is located outward of the second reinforcing body 22.

[0031] More specifically, as shown in Figure 3, for at least some of the overlapping areas OP, the first overlapping area OP1 and the second overlapping area OP2 are arranged alternately along the longitudinal direction of the shaft 10 (the direction parallel to the central axis Ax). In other words, the first overlapping area OP1 and the second overlapping area OP2 are arranged regularly along the longitudinal direction of the shaft 10. In this embodiment, however, for all overlapping areas OP, the first overlapping area OP1 and the second overlapping area OP2 are arranged alternately along the longitudinal direction of the shaft 10.

[0032] The first reinforcing body 21 and the second reinforcing body 22, having such a configuration, can be manufactured, for example, by using a braiding machine to braid each wire while relatively moving a bobbin for eight strands 21a for the first reinforcing body 21 and a bobbin for one strand 22a for the second reinforcing body 22.

[0033] A-3. Effects of this embodiment: As described above, the catheter 100 of this embodiment comprises a cylindrical shaft 10, a first reinforcing body 21, and a second reinforcing body 22. The first reinforcing body 21 is composed of a plurality of strands 21a spirally wound around the shaft 10. The second reinforcing body 22 is composed of at least one strand 22a spirally wound around the shaft 10 so as to overlap with the first reinforcing body 21 in the radial direction of the shaft 10. At the first overlapping area OP1, which is part of the plurality of overlapping areas OP of the first reinforcing body 21 and the second reinforcing body 22, the first reinforcing body 21 is located radially inward of the shaft 10 than the second reinforcing body 22, and at the second overlapping area OP2, which is another part of the plurality of overlapping areas OP, the first reinforcing body 21 is located radially outward of the shaft 10 than the second reinforcing body 22.

[0034] Because the catheter 100 of this embodiment has such a configuration, the elongation resistance of the shaft 10 can be improved, as will be explained below. Figure 4 is a schematic explanatory diagram showing the configuration of the first reinforcing body 21 and the second reinforcing body 22 in the catheter 100 of this embodiment. Figure 5 is a schematic explanatory diagram showing the configuration of the first reinforcing body 21 and the second reinforcing body 22 in the catheter 100X1 of the first comparative example, and Figure 6 is a schematic explanatory diagram showing the configuration of the first reinforcing body 21 and the second reinforcing body 22 in the catheter 100X2 of the second comparative example.

[0035] In the catheter 100X1 of the first comparative example shown in Figure 5, all of the multiple overlapping points OP between the first reinforcing member 21 and the second reinforcing member 22 are second overlapping points OP2 where the first reinforcing member 21 is located outside the second reinforcing member 22. Therefore, the first reinforcing member 21 is not restrained by the second reinforcing member 22. Although the second reinforcing member 22 is restrained by the tension of the first reinforcing member 21, the restraining force is small. Therefore, when the shaft 10 attempts to stretch, the first reinforcing member 21 and the second reinforcing member 22 stretch or shift position, and the elongation resistance of the shaft 10 cannot be sufficiently improved by the first reinforcing member 21 and the second reinforcing member 22.

[0036] Furthermore, in the catheter 100X2 of the second comparative example shown in Figure 6, all of the multiple overlapping points OP between the first reinforcing body 21 and the second reinforcing body 22 are first overlapping points OP1 where the first reinforcing body 21 is located inside the second reinforcing body 22. Therefore, the second reinforcing body 22 is not restrained by the first reinforcing body 21. Although the first reinforcing body 21 is restrained by the tension of the second reinforcing body 22, the restraining force is small. Therefore, when the shaft 10 attempts to stretch, the first reinforcing body 21 and the second reinforcing body 22 stretch or shift position, and the elongation resistance of the shaft 10 cannot be sufficiently improved by the first reinforcing body 21 and the second reinforcing body 22.

[0037] In contrast, as shown in Figure 4, the catheter 100 of this embodiment has a mixture of a first overlapping area OP1 where the first reinforcing body 21 is located inside the second reinforcing body 22, and a second overlapping area OP2 where the first reinforcing body 21 is located outside the second reinforcing body 22. As a result, the first reinforcing body 21 and the second reinforcing body 22 restrain each other. Therefore, when the shaft 10 attempts to stretch, the first reinforcing body 21 and the second reinforcing body 22 restrain each other, suppressing stretching and displacement, and the elongation resistance of the shaft 10 can be sufficiently improved by the first reinforcing body 21 and the second reinforcing body 22.

[0038] Thus, according to the catheter 100 of this embodiment, the stretch resistance of the shaft 10 can be sufficiently improved by the first reinforcing body 21 and the second reinforcing body 22, thereby suppressing the breakage of the shaft 10. Furthermore, it is possible to suppress the stacking of the accompanying device that passes through the lumen 10M of the shaft 10, or the obstruction of the smooth flow of fluid in the lumen 10M, due to the stretching of the shaft 10. In addition, it is possible to suppress changes in the position of the markers (first marker 18 and second marker 19) provided at the tip of the shaft 10 and the spacing between the multiple markers due to the stretching of the shaft 10, thereby suppressing a decrease in the accuracy of positioning for administering objects based on the position of the markers.

[0039] Furthermore, in the shaft 10 of this embodiment, at least in some overlapping areas OP, a first overlapping area OP1 where the first reinforcing body 21 is located inside the second reinforcing body 22 and a second overlapping area OP2 where the first reinforcing body 21 is located outside the second reinforcing body 22 are regularly arranged along the longitudinal direction of the shaft 10. Therefore, according to the catheter 100 of this embodiment, the elongation resistance of the shaft 10 can be further effectively improved by the strong restraint between the first reinforcing body 21 and the second reinforcing body 22.

[0040] Furthermore, in the shaft 10 of this embodiment, at least in some overlapping areas OP, a first overlapping area OP1 where the first reinforcing body 21 is located inside the second reinforcing body 22 and a second overlapping area OP2 where the first reinforcing body 21 is located outside the second reinforcing body 22 are alternately arranged along the longitudinal direction of the shaft 10. Therefore, according to the catheter 100 of this embodiment, the first reinforcing body 21 and the second reinforcing body 22 further restrain each other, thereby extremely effectively improving the elongation resistance of the shaft 10.

[0041] Furthermore, in the shaft 10 of this embodiment, the number of strands 22a constituting the second reinforcing body 22 is less than the number of strands 21a constituting the first reinforcing body 21. Therefore, according to the catheter 100 of this embodiment, it is possible to improve the elongation resistance of the shaft 10 while suppressing the decrease in the flexibility of the shaft 10 due to the presence of the second reinforcing body 22.

[0042] Furthermore, in the shaft 10 of this embodiment, the number of strands 22a constituting the second reinforcing body 22 is one. Therefore, according to the catheter 100 of this embodiment, it is possible to effectively suppress the decrease in flexibility of the shaft 10 due to the presence of the second reinforcing body 22 while improving the elongation resistance of the shaft 10.

[0043] Furthermore, in the shaft 10 of this embodiment, the winding direction of the second reinforcing body 22 and the winding direction of the first reinforcing body 21 are opposite. Therefore, in the catheter 100 of this embodiment, the number of overlapping points OP between the first reinforcing body 21 and the second reinforcing body 22 can be increased compared to a configuration in which the winding direction of the second reinforcing body 22 and the winding direction of the first reinforcing body 21 are in the same direction. Accordingly, with the catheter 100 of this embodiment, the elongation resistance of the shaft 10 can be effectively improved by further strengthening the restraint between the first reinforcing body 21 and the second reinforcing body 22.

[0044] B. Variations: The technologies disclosed herein are not limited to the embodiments described above and can be modified in various forms without departing from their essence, for example, the following modifications are possible.

[0045] The configuration of the catheter 100 in the above embodiment is merely an example and can be modified in various ways. For example, in the above embodiment, along the longitudinal direction of the shaft 10, first overlapping points OP1 where the first reinforcing body 21 is located inside the second reinforcing body 22 and second overlapping points OP2 where the first reinforcing body 21 is located outside the second reinforcing body 22 are arranged alternately. However, the arrangement of the first overlapping points OP1 and second overlapping points OP2 is not limited to this. For example, at least some of the overlapping points OP may be configured such that M (M is an integer of 1 or more) first overlapping points OP1 and N (N is an integer of 1 or more) second overlapping points OP2 are arranged alternately along the longitudinal direction of the shaft 10. In this configuration, the first overlapping points OP1 and second overlapping points OP2 can be said to be arranged in a regular manner. Alternatively, the first overlapping points OP1 and second overlapping points OP2 may be arranged irregularly along the longitudinal direction of the shaft 10.

[0046] In the above embodiment, the first reinforcing body 21 is composed of eight strands 21a, but the number of strands 21a constituting the first reinforcing body 21 can be arbitrarily set as long as there are multiple strands. Also, in the above embodiment, the second reinforcing body 22 is composed of one strand 22a, but the number of strands 22a constituting the second reinforcing body 22 can be arbitrarily set. Also, in the above embodiment, the number of strands 22a constituting the second reinforcing body 22 is less than the number of strands 21a constituting the first reinforcing body 21, but the number of strands 22a constituting the second reinforcing body 22 may be equal to or greater than the number of strands 21a constituting the first reinforcing body 21.

[0047] In the above embodiment, the first reinforcing member 21 is wound in a Z direction around the shaft 10, and the second reinforcing member 22 is wound in an S direction around the shaft 10. However, conversely, the first reinforcing member 21 may be wound in an S direction around the shaft 10, and the second reinforcing member 22 may be wound in a Z direction around the shaft 10. Also, in the above embodiment, the winding direction of the second reinforcing member 22 and the winding direction of the first reinforcing member 21 are opposite, but the winding direction of the second reinforcing member 22 and the winding direction of the first reinforcing member 21 may be the same.

[0048] In the above embodiment, the tip-side reinforcing body 20 is embedded in the tip of the shaft 10, but the tip-side reinforcing body 20 may be embedded in the base end of the shaft 10, in the intermediate part of the shaft 10 excluding the tip and base ends, or along the entire length of the shaft 10.

[0049] In the above embodiment, the shaft 10 is provided with two markers (a first marker 18 and a second marker 19), but the shaft 10 may be provided with only one marker, or the shaft 10 may not be provided with any markers at all. [Explanation of symbols]

[0050] 10: Shaft 10M: Lumen 11: Inner layer 12: Outer layer 18: First marker 19: Second marker 20: Tip reinforcement 21: First reinforcement 21a: Wire strand 22: Second reinforcement 22a: Wire strand 30: Proximal reinforcement 90: Connector 91: Main body 92: Wings 100: Catheter OP1: First overlap OP2: Second overlap OP: Overlap

Claims

1. A catheter comprising: A cylindrical shaft; A first reinforcing body composed of a plurality of wires wound in a spiral shape around the shaft; A second reinforcing body composed of at least one wire spirally wound around the shaft so as to overlap with the first reinforcing body in the radial direction of the shaft; Equipped with At a first overlapping portion which is a part of a plurality of overlapping portions between the first reinforcing body and the second reinforcing body, the first reinforcing body is located radially inward of the shaft than the second reinforcing body, and at a second overlapping portion which is another part of the plurality of overlapping portions, the first reinforcing body is located radially outward of the shaft than the second reinforcing body, The plurality of wires constituting the first reinforcing body are arranged so as to be in contact with each other along the longitudinal direction of the shaft. catheter.

2. 2. The catheter of claim 1, For at least a portion of the overlapping portions, the first overlapping portions and the second overlapping portions are regularly arranged along the longitudinal direction of the shaft. catheter.

3. 3. The catheter of claim 2, For at least some of the overlapping portions, the first overlapping portions and the second overlapping portions are alternately arranged along the longitudinal direction of the shaft. catheter.

4. A catheter according to any one of claims 1 to 3, The number of wires constituting the second reinforcing body is less than the number of wires constituting the first reinforcing body. catheter.

5. A catheter according to any one of claims 1 to 3, The winding direction of the second reinforcing body and the winding direction of the first reinforcing body are opposite to each other. catheter.

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