Steerable Catheter

Abstract

The present invention aims to reduce the number of parts and the number of manufacturing steps. [Solution] A movable catheter 1 includes a tube 2 having a main lumen 22. The tube 2 has multiple wire lumens 23a, 23b, with approximately half W1a of one end thereof inserted into one of the wire lumens 23a, a middle portion W1c of the tube 2 folded back at the distal end of the tube 2, and approximately half W1b of the other end thereof inserted into the other one of the wire lumens 23b, with one end and the other end of the wire W1 positioned on the proximal end side of the tube 2. [Selected Figure] Figure 2B

Description

[Technical field]

[0001] The present invention relates to a catheter, which is a medical treatment tool used for performing various types of treatments and examinations, and in particular to a steerable catheter whose tip portion can be freely deflected. [Background technology]

[0002] As medical treatment devices (including, for example, contrast agent injection catheters, electrode catheters, ablation catheters, and catheter sheaths) that are inserted through body cavities, lumens, blood vessels, etc. to target tissues such as various organs (for example, the bile duct and the heart), movable catheters are known in which the direction of the tip (distal end) of the catheter inserted into the body can be deflected by operating an operating unit provided on the base end (proximal end) of the catheter placed outside the body in order to facilitate insertion and access to the target tissue (see, for example, Patent Documents 1 and 2).

[0003] The catheter described in Patent Document 1 is an endoscopic catheter used for injecting an X-ray contrast medium into the bile duct for examination inside the bile duct, and is a catheter that is inserted into the duodenum via an endoscope, and then the tip can be deflected (curved) by operating a control wire from outside the body so that the tip can be easily inserted from the duodenal side into the duodenal papilla and reach the bile duct. The catheter described in Patent Document 1 has a lumen into which a control wire for deflecting the tip is inserted, in addition to a large-diameter lumen used for injecting a contrast medium, and the control wire is joined to a tip tip provided at the tip of the catheter by means of plasma welding or the like, so that the tip of the catheter can be deflected by pulling the control wire outside the body.

[0004] The movable-tip catheter described in Patent Document 2 is a catheter used for guiding an ablation catheter to a site of the heart to be treated in order to perform catheter ablation treatment on the heart, and the tip can be deflected (curved) by operating an operating unit from outside the body so that the tip of the ablation catheter can be easily guided to a desired position in the heart. The catheter tube constituting the catheter described in Patent Document 2 has a pair of wire lumens at positions 180° opposite each other in the tube wall in addition to a main lumen into which various treatment tools are inserted. The rigidity of the part to be deflected at the tip of the catheter tube is set to be gradually lower, for example, as it approaches the tip, and the tips of a pair of wires inserted into each of the wire lumens are connected to a ring (pull ring) integrally attached to the tip by means of laser welding or the like, and the base ends of the pair of wires are connected to the operating unit. By operating the operating unit, one wire is pulled and the other wire is loosened, so that the direction of the tube tip can be controlled.

[0005] However, in the conventional techniques described in Patent Documents 1 and 2, the tip of the wire for deflection operation is connected and fixed to the member (tip or pull ring) attached to the tip of the catheter by means of plasma welding, laser welding, or the like, and there are problems in that the number of parts increases by the number of members (tip or pull ring) for fixing the wire, and the work of attaching the member to the catheter and the work of connecting and fixing the tip of the wire to the member are complicated. In addition, since it is necessary to secure an area for providing the member for fixing the wire within the structure of the catheter, there is also a problem in that structural restrictions are imposed on the catheter, for example, it becomes necessary to narrow the tip opening area of ​​the main lumen. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2002-272675 A [Patent Document 2] JP 2014-188039 A Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a steerable catheter capable of reducing the number of parts and the number of manufacturing steps. [Means for solving the problem]

[0008] In order to achieve the above object, a steerable catheter according to a first aspect of the present invention comprises: A steerable catheter comprising a tube having a main lumen, The tube has a plurality of spaced apart wire lumens extending from a proximal end to a distal end of the tube, the wire lumens being disposed outside the main lumen, Approximately half of one end of the tube is inserted into one of the wire lumens, the middle portion of the tube is folded back at the distal end of the tube, and approximately half of the other end of the tube is inserted into the other one of the wire lumens, with one end and the other end of the tube comprising at least one wire arranged on the proximal end side of the tube.

[0009] In the movable catheter according to the first aspect of the present invention, the wire is folded back at the distal end of one of the wire lumens through which approximately half of one end of the wire is inserted, and at the distal end of the other wire lumen through which approximately half of the other end of the wire is inserted, so that a force for deflecting the wire can be applied to the distal end of the tube by simultaneously pulling both ends (one end and the other end) of the wire arranged on the proximal end side of the tube. Therefore, it is possible to deflect the distal end of the tube according to the arrangement of the pair of wire lumens through which the wire is inserted. Therefore, there is no need to provide a member for fixing the wire, such as a tip or pull ring in the prior art, and the number of parts can be reduced, and there is no need to attach a member for fixing the wire to the catheter tube or connect the wire to the member, so the number of man-hours in the manufacture can be reduced. In addition, there is no need to secure an area for providing a member for fixing the wire within the structure of the catheter, so that the structural restrictions of the catheter can be reduced.

[0010] In the steerable catheter according to the first aspect of the present invention, three or more wire lumens may be provided, and two or more wires may be provided, so that the distal end of the tube can be deflected in two or more directions.

[0011] In the steerable catheter according to the first aspect of the present invention, the tube may comprise a single-lumen tube having the main lumen, and at least one multi-lumen tube having a plurality of lumens for wires, which is integrally disposed outside the single-lumen tube. The tube may comprise a single tube having a main lumen, in which a plurality of lumens for wires are formed within the tube wall, but it may also comprise a multi-lumen tube disposed outside the single-lumen tube, which can improve the productivity of the steerable catheter.

[0012] In order to achieve the above object, a steerable catheter according to a second aspect of the present invention comprises: A steerable catheter comprising a tube having a main lumen, The tube has a wire lumen outside the main lumen, the wire lumen extending from the proximal end to the distal end of the tube; Approximately half of one end of the wire is inserted into the wire lumen, the middle portion is folded back at the distal end of the tube, and approximately half of the other end is passed outside the tube, with one end and the other end of the wire being positioned on the proximal end side of the tube.

[0013] In order to achieve the above object, a steerable catheter according to a third aspect of the present invention comprises: A steerable catheter comprising a tube having a main lumen, The tube has a wire lumen outside the main lumen, the wire lumen extending from the proximal end to the distal end of the tube; Approximately half of one end of the tube is inserted into the wire lumen, the middle portion of the tube is folded back at the distal end of the tube, and approximately half of the other end of the tube is inserted into the main lumen, with one end and the other end of the tube comprising a wire arranged on the proximal end side of the tube.

[0014] In the movable catheter according to the second and third aspects of the present invention, the wire is folded back at the distal end of the wire lumen through which approximately half of one end of the wire is inserted, and approximately half of the other end of the wire is passed through the outside of the tube or inside the main lumen, so that a force for deflecting the wire can be applied to the distal end of the catheter tube by simultaneously pulling both ends (one end and the other end) of the wire arranged on the proximal end side of the tube. Therefore, it is possible to deflect the distal end of the tube according to the arrangement of the wire lumen through which the wire is inserted. Therefore, there is no need to provide a member for fixing the wire, such as a tip or pull ring in the prior art, and the number of parts can be reduced, and there is no need to attach a member for fixing the wire to the catheter tube or connect the wire to the member, so the number of man-hours in the manufacture can be reduced. In addition, there is no need to secure an area for providing a member for fixing the wire within the structure of the catheter, so that the structural restrictions of the catheter can be reduced. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a plan view showing the external configuration of a steerable catheter according to an embodiment of the present invention. [Figure 2A] FIG. 2A is a cross-sectional view taken along line IIa-IIa in FIG. [Figure 2B] 2B is an enlarged perspective view showing a main portion of the steerable catheter of FIG. 1. FIG. [Figure 2C] FIG. 2C is a cross-sectional view of the sheath body of the steerable catheter of FIG. 2B taken along a plane passing through the central axes of each of the pair of wire lumens. [Figure 3A] FIG. 3A is a perspective view showing an increased number of wires inserted through the wire lumens of the steerable catheter of FIG. 2B. [Figure 3B] FIG. 3B is a cross-sectional view of the sheath body of the steerable catheter of FIG. 3A cut along a plane perpendicular to its central axis. [Figure 3C]3C is a cross-sectional view of the sheath body of the steerable catheter of FIG. 3A taken along a plane passing through the central axes of each of the pair of wire lumens. [Figure 4A] FIG. 4A shows a variation of the steerable catheter of FIG. 3A. [Figure 4B] FIG. 4B shows another variation of the steerable catheter of FIG. 3A. [Figure 4C] FIG. 4C shows yet another variation of the steerable catheter of FIG. 3A. [Figure 5A] FIG. 5A is an enlarged perspective view showing a main portion of a steerable catheter according to another embodiment of the present invention. [Figure 5B] FIG. 5B is a cross-sectional view of the sheath body of the steerable catheter of FIG. 5A taken along a plane perpendicular to its central axis. [Figure 5C] FIG. 5C is a cross-sectional view of the sheath body of the steerable catheter of FIG. 5A taken along a plane passing through the central axes of each of the pair of wire lumens. [Figure 6A] FIG. 6A is an enlarged perspective view showing a main portion of a steerable catheter according to still another embodiment of the present invention. [Figure 6B] FIG. 6B is a cross-sectional view of the sheath body of the steerable catheter of FIG. 6A cut along a plane perpendicular to its central axis. [Figure 6C] 6C is a cross-sectional view of the sheath body of the steerable catheter of FIG. 6A taken along a plane passing through the central axes of the pair of wire lumens. [Figure 7] FIG. 7 is a cross-sectional view showing the configuration of a sheath body of a steerable catheter according to still another embodiment of the present invention. [Figure 8] FIG. 8 is a cross-sectional view showing the configuration of a sheath body of a steerable catheter according to still another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be specifically described with reference to the drawings. The catheter sheath (movable sheath) as a movable catheter of this embodiment is a catheter that is inserted prior to an electrode catheter for detecting an electrocardiogram or an ablation catheter for cauterizing an affected area when performing catheter ablation, for example, and guides these electrode catheters and ablation catheters. In the following, a catheter sheath will be described as an example of a movable catheter to which the present invention is applied, but the present invention can also be applied to an electrode catheter, an ablation catheter, a movable endoscopic catheter used for injecting an X-ray contrast agent into a bile duct for examination inside the bile duct, and other movable catheters.

[0017] Catheter ablation is a therapy for treating arrhythmias occurring in the heart. An ablation catheter having a high-frequency electrode at its tip is inserted through a blood vessel to the myocardial tissue causing the arrhythmia, and the myocardial tissue or its vicinity is cauterized at about 60-70°C to cause coagulation necrosis, thereby interrupting the arrhythmia circuit.

[0018] First, reference will be made to Figure 1 and Figures 2A to 2C. A catheter sheath (movable catheter) 1 is generally configured to include a sheath body (tube) 2, an operation section 3, a grip section 4, and a pair of wires W1, W2.

[0019] The sheath body 2 is made of a hollow tube, and although not shown in the figure, for example, a multi-layer tube including a braid layer made of meshed stainless steel or the like and multiple resin layers is used. A part of the distal end side of the sheath body 2 is a deflection section 21 whose direction can be arbitrarily deflected, and the deflection section 21 is set to have lower rigidity (more flexible) than the remaining part, and furthermore, the deflection section 21 is set so that its rigidity gradually or stepwise decreases toward its tip.

[0020] The material of the sheath body 2 is not particularly limited as long as it is flexible, but is preferably a thermoplastic resin or a thermoplastic elastomer, and examples of the material that can be used include polyamide-based elastomers such as polyether block amide copolymers, polyamide, polyimide, polyamideimide, polyethylene terephthalate, polyethylene, polypropylene, polyurethane, ethylene-vinyl acetate copolymers, polyvinyl chloride, polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymers, and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymers.

[0021] The operating section 3 and the grip section 4 attached to the proximal end of the sheath body 2 have an insertion hole through which the proximal end portion of the sheath body 2 is inserted, and a sheath hub 41a is attached to the proximal end of the grip section 4.

[0022] The sheath hub 41a has an inner cavity, and the sheath body 2 in the grip section 4 is attached to the proximal end side of the sheath hub 41a so that the inner cavity of the sheath hub 41a communicates with the main lumen 22 of the sheath body 2. A catheter insertion port equipped with a hemostatic valve is formed on the distal end side of the sheath hub 41a. When the catheter sheath 1 is used (during treatment), the electrode catheter or ablation catheter described above is inserted from the catheter insertion port of the sheath hub 41a and guided to the main lumen 22 of the sheath body 2, and the distal end of each is guided to the myocardial tissue to be treated. A side injection tube is formed on the side of the sheath hub 41a, and a three-way stopcock 41c is attached to the side injection tube via a tube 41b. For example, a syringe or the like can be attached to the three-way stopcock 41c to suck blood from the body or to feed a medicinal solution into the body.

[0023] A generally cylindrical tip protection member 29 made of resin and having a hemispherical distal end is provided at the distal end (the tip of the deflection section 21) of the sheath body 2. The tip protection member 29 has an inner cavity with approximately the same diameter as the main lumen 22 of the sheath body 2, and is integrally joined (fixed) to the distal end of the sheath body 2 by heat fusion or the like. However, the tip protection member 29 may be omitted.

[0024] Four wire lumens (sub-lumens) 23a to 23d are formed within the tube wall of the sheath body 2, surrounding the outside of the main lumen 22 and extending approximately parallel to the main lumen 22. The wire lumens 23a to 23d are formed from the proximal end to the distal end of the sheath body 2. The wire lumens 23a to 23d are formed around the central axis of the sheath body 2, outside the main lumen 22, and spaced apart from each other at an angular pitch (angular interval) of approximately 90°.

[0025] In this embodiment, the wire lumens 23a to 23d are formed to open at the distal end surface of the sheath body 2 to which the tip protection member 29 is joined. However, the wire lumens 23a to 23d may be formed to open at the side surface of the sheath body 2 in the vicinity of the distal end surface of the sheath body 2, without reaching the distal end surface to which the tip protection member 29 of the sheath body 2 is joined. Furthermore, the wire lumens 23a to 23d may not open to the outside of the sheath body 2, but may communicate with the distal end of the wire lumen 23a and the distal end of the wire lumen 23b, and communicate with the distal end of the wire lumen 23c and the distal end of the wire lumen 23d, in the vicinity of the distal end surface of the sheath body 2. In this case, these communication parts may be formed in a substantially U-shape so as not to interfere with the insertion of the wires W1 and W2.

[0026] A single wire W1 is inserted through the wire lumens 23a and 23b, and a single wire W2 is inserted through the wire lumens 23c and 23d. In this embodiment, the wires W1 and W2 are made of a metal such as stainless steel, but the wires W1 and W2 may be made of other materials such as resin.

[0027] The wire W1 is disposed such that approximately half W1a on one end side is inserted into the wire lumen 23a, its middle portion W1c is folded back at the distal end surface to which the tip protection member 29 of the sheath body 2 is joined, and approximately half W1b on the other end side is inserted into the wire lumen 23b, and both ends (one end and the other end) are located in the operation unit 3 on the proximal end side of the sheath body 2. Similarly, the wire W2 is disposed such that approximately half W2a on one end side is inserted into the wire lumen 23c, its middle portion W2c is folded back at the distal end surface to which the tip protection member 29 of the sheath body 2 is joined, and approximately half W2b on the other end side is inserted into the wire lumen 23d, and both ends (one end and the other end) are located in the operation unit 3 on the proximal end side of the sheath body 2.

[0028] Both ends of the wire W1 and both ends of the wire W2 are drawn out from side holes provided in the sheath body 2 inside the operation section 3 provided on the proximal end side of the sheath body 2 and are each connected to the operation section 3 (rotation operation member 31). The operation section 3 has a pair of protruding gripping portions 32, 32, and is held by a holding portion 42 provided on the tip (distal end) side of the grip portion 4 via a screw-in type knob member 5.

[0029] In the neutral state shown in FIG. 1, both wires W1 and W2 are in an untensioned state (or in a state in which they are loosely tensed approximately equally), and the deflection portion 21 at the tip of the sheath body 2 is in a linearly extended state as shown in the figure.

[0030] From this neutral state, by appropriately pressing the gripping portions 32, 32 of the rotating operating member 31, the rotating operating member 31 is rotated in the direction of arrow B1 in Figure 1. With this rotation, the wire W1 is pulled and the wire W2 is loosened, so that the deflection portion 21 at the tip is deflected as shown by the arrow B3 in Figure 1.

[0031] Conversely, when the gripping portions 32, 32 of the rotating operating member 31 are appropriately pressed and the rotating operating member 31 is rotated in the direction of arrow B2 in Figure 1, the wire W1 is loosened and the wire W2 is pulled, thereby deflecting the deflection portion 21 at the tip as shown by the arrow B4 in Figure 1.

[0032] When it is desired to fix the shape of the deflection unit 21 in a deflected state, the knob member 5 is rotated clockwise to be tightened, whereby the rotation operation member 31 is pressed against the holding portion 42, the rotation operation member 31 is fixed at the current position, and the shape of the deflection unit 21 is fixed. When it is desired to release the fixed shape of the deflection unit 21 (when it is desired to adjust the deflection state), the knob member 5 is rotated counterclockwise to be loosened, in the opposite manner to the above, whereby the rotation operation member 31 is loosely pressed against the holding portion 42, and the rotation operation member 31 is in a rotatable state. As a result, the fixed shape of the deflection unit 21 is released, and the deflection state of the deflection unit 21 can be adjusted by gripping the grip portion 32 and rotating the rotation operation member 31.

[0033] In the embodiment described above, the wire W1 is folded back at the distal end of the wire lumen 23a through which approximately half W1a of one end side of the wire W1 is inserted and at the distal end of the wire lumen 23b through which approximately half W1b of the other end side of the wire W1 is inserted, so that by pulling both ends of the wire W1 arranged on the proximal end side of the sheath body 2, a force for deflecting the wire W1 can be applied to the distal end of the sheath body 2. Therefore, it is possible to deflect the distal end (deflection portion 21) of the sheath body 2 depending on the arrangement of the pair of wire lumens 23a, 23b through which the wire W1 is inserted with respect to the central axis of the sheath body 2. The same applies to the wire W2.

[0034] Therefore, there is no need to provide a member for fixing the wire, such as a tip or pull ring in the prior art, and the number of parts can be reduced, and since there is no need to attach a member for fixing the wire to the catheter tube or connect the wire to that member, the number of manufacturing steps can be reduced. Also, since there is no need to secure an area for providing a member for fixing the wire within the structure of the catheter sheath 1, structural restrictions on the catheter sheath 1 can be reduced, and for example, it becomes possible to increase the opening area of ​​the distal end (tip) of the sheath body 2 (main lumen 22).

[0035] In addition, both the approximately half W1a of the wire W1 inserted in the wire lumen 23a and the approximately half W1b inserted in the wire lumen 23b are pulled to apply a force for deflecting the deflection portion 21. Therefore, the force can be applied to a relatively wide range in the circumferential direction of the sheath body 2 according to the interval (angular interval) between the wire lumen 23a and the wire lumen 23b. The same applies to the wire W2. As a result, compared to the prior art in which a deflection operation is performed by pulling a single wire that is not folded back and inserted in a single lumen, the force applied to the wire is smaller, and the risk of wire breakage accompanying the deflection operation is reduced.

[0036] In the above-described embodiment, the wires W1 and W2 have the same specifications, including their wire diameter (cross-sectional area), but these may be made different, for example, the wire diameter of wire W1 may be made thicker (cross-sectional area larger) than the wire diameter of wire W2.

[0037] In the above embodiment, the wire lumens 23a-23d are arranged at equal angular pitches (90° pitches), but they do not have to be arranged at equal angular pitches and may be arranged at different angular intervals. By appropriately setting the angular intervals, the curvature and deflection direction of the deflection section 21 can be appropriately set.

[0038] Furthermore, in the above-described embodiment, two wires are used: wire W1 inserted through wire lumen 23a and wire lumen 23b, and wire W2 inserted through wire lumen 23c and wire lumen 23d. However, as shown in Figures 3A to 3C, wire W3 and wire W4 may be added to form a configuration in which four wires are used.

[0039] That is, the wire W3 has approximately one half W3a on one end inserted into the wire lumen 23a, its middle part W3c folded back at the distal end surface to which the tip protection member 29 of the sheath body 2 is joined, and the other half W3b on the other end inserted into the wire lumen 23c. The wire W4 has approximately one half W4a on one end inserted into the wire lumen 23b, its middle part W4c folded back at the distal end surface to which the tip protection member 29 of the sheath body 2 is joined, and the other half W4b on the other end inserted into the wire lumen 23d. With this configuration, the wires W1 to W4 can be deflected in four directions by appropriately selecting and pulling one of the wires W1 to W4. In addition, the deflection section 21 can be deflected in any direction 360° by appropriately selecting a combination of two adjacent wires from the wires W1 to W4 and adjusting the balance of the pulling force of each wire. In response to the addition of the wires W3 and W4, it is necessary to appropriately change the configuration of the operation unit 3, for example by adding a rotation operation member similar to the rotation operation member 31 to the operation unit 3.

[0040] In addition, in the example shown in Figures 3A to 3C, a case was described in which four wire lumens 23a to 23d and four wires W1 to W4 are provided, but as shown in Figures 4A to 4C, for example, the number of wire lumens can be increased or decreased, and therefore the number of wires can also be increased or decreased.

[0041] That is, in FIG. 4A, six wire lumens 24a are provided at an angle pitch of 60°, and six wires W5 are provided. As a result, when the wires W5 are pulled one by one, the deflection unit 21 can be deflected in six directions, and by appropriately selecting a combination of two adjacent wires W5 and adjusting the balance of the pulling force, the deflection unit 21 can be deflected in any direction of 360°. In FIG. 4B, three wire lumens 25a are provided at an angle pitch of 120°, and three wires W6 are provided. As a result, when the wires W6 are pulled one by one, the deflection unit 21 can be deflected in three directions, and by appropriately selecting a combination of two adjacent wires W6 and adjusting the balance of the pulling force, the deflection unit 21 can be deflected in any direction of 360°. In FIG. 4C, 24 wire lumens 26a are provided at an angle pitch of 15°, and 24 wires W7 are provided. Thereby, when the wires W7 are pulled one by one, the deflection portion 21 can be deflected in the direction 24. These are merely examples, and the number of wire lumens may be two or more, and the number of wires may be one or more.

[0042] In the example shown in Figures 4A to 4C, the number of wire lumens and the number of wires are the same, but they may be different, for example, the number of wires may be less than the number of wire lumens. Also, in the example shown in Figures 4A to 4C, both ends of the wire are inserted through a pair of adjacent wire lumens, but for example, a pair of wire lumens may be intermittently selected and both ends of the wire may be inserted through them.

[0043] Although not shown, the number of wire lumens may be two and the number of wires may be one. This allows the deflection section 21 to be deflected in one direction. In this case, it is preferable to arrange these wire lumens at an angular interval of less than 180°. This makes it easier to deflect the distal end of the sheath body 2 towards the pair of wire lumens through which the wire is inserted when both ends of the wire are pulled simultaneously.

[0044] In the above-described embodiment, approximately half W1a on one end side and approximately half W1b on the other end side of the wire W1 are inserted through the pair of wire lumens 23a, 23b, but a configuration as shown in Figures 5A to 5C may be used. That is, in the configuration shown in Figures 5A to 5C, approximately half W8a on one end side of the wire W8 is inserted through the wire lumen 27a formed in the sheath body 2, the middle portion W8c of the wire W8 is folded back at the distal end of the sheath body 2, and approximately half W8b on the other end side of the wire W8 is passed outside the sheath body 2, with both ends (one end and the other end) disposed on the proximal end side of the sheath body 2. Similarly, approximately half W9a of one end of the wire W9 is inserted through the wire lumen 27b formed in the sheath body 2, an intermediate portion W9c of the wire W9 is folded back at the distal end of the sheath body 2, and approximately half W9b of the other end of the wire W9 is passed outside the sheath body 2, with both ends (one end and the other end) being disposed on the proximal end side of the sheath body 2. According to the example shown in Figures 5A to 5C, it is possible to reduce the number of wire lumens while achieving the same effects as the configuration shown in Figures 2A to 2C.

[0045] Furthermore, the catheter sheath may be configured as shown in Figures 6A to 6C. That is, in the configuration shown in Figures 6A to 6C, approximately half W10a of one end of the wire W10 is inserted through the wire lumen 28a formed in the sheath body 2, the middle portion W10c of the wire W10 is folded back at the distal end of the sheath body 2, and approximately half W10b of the other end of the wire W10 is inserted through the main lumen 22 formed in the sheath body 2, with both ends (one end and the other end) being disposed on the proximal end side of the sheath body 2. Similarly, approximately half W11a of one end of the wire W11 is inserted through the wire lumen 28b formed in the sheath body 2, the middle portion W11c of the wire W11 is folded back at the distal end of the sheath body 2, and approximately half W11b of the other end of the wire W11 is inserted through the main lumen 22 formed in the sheath body 2, with both ends (one end and the other end) being disposed on the proximal end side of the sheath body 2. The example shown in Figures 6A to 6C also makes it possible to reduce the number of wire lumens while achieving the same effects as the configuration shown in Figures 2A to 2C.

[0046] Furthermore, in the above-described embodiment, a plurality of wire lumens are formed within the tube wall of the sheath body 2 having the main lumen 22. However, as shown in FIG. 7, a single-lumen tube 200 having a main lumen 200a and one or more multi-lumen tubes 201 having a plurality of wire lumens 201a, 201b may be combined and integrated into the sheath body.

[0047] 7 shows an example in which four multi-lumen tubes 201 having an approximately elliptical cross section and a pair of wire lumens 201a, 201b each having an approximately circular cross section are arranged around a single-lumen tube 200 having a main lumen 200a, and approximately half W12a of one end side of the wires W12 (four in total) is inserted into the wire lumen 201a, and approximately half W12b of the other end side of the wires W12 is inserted into the wire lumen 201b. The single-lumen tube 200 and the multi-lumen tube 201 can be integrated with each other by bonding with an adhesive, heat welding, or the like. It is not necessarily easy to manufacture a sheath body 2 having a main lumen 22 with multiple wire lumens formed in its tube wall, but by combining and integrating multiple tubes in this way, productivity can be improved.

[0048] Furthermore, in the embodiment shown in FIG. 7, the sheath body is formed by combining and integrating single-lumen tube 200 and multi-lumen tube 201, but as shown in FIG. 8, the sheath body may be formed by combining a single-lumen tube 202 having a main lumen 202a with a plurality of elongated members 203 and integrating them so that gaps are formed between the single-lumen tube 202 and the elongated members 203, and the gaps may be used as wire lumens 204a, 204b.

[0049] In FIG. 8, four solid elongated members 203 with an approximately elliptical cross section are arranged around a single-lumen tube 202 with a main lumen 202a and an approximately circular cross section, and four gaps with an approximately triangular cross section formed between the single-lumen tube 202 and the two elongated members 203 are used as two pairs of wire lumens 204a, 204b, and approximately half W13a of one end side of the wire W13 (two wires in total) is inserted into the wire lumen 204a, and approximately half W13b of the other end side of the wire W13 is inserted into the wire lumen 204b. The single-lumen tube 202 and the elongated member 203 can be integrated with each other by bonding with an adhesive or heat welding. In this embodiment, a multi-lumen tube is not required, so productivity can be further improved.

[0050] The above-described embodiments are described for the purpose of facilitating understanding of the present invention, and are not described for the purpose of limiting the present invention. Therefore, each element disclosed in the above-described embodiments is intended to include all design modifications and equivalents that fall within the technical scope of the present invention. [Explanation of symbols]

[0051] 1...Catheter sheath (movable catheter) 2…Sheath body (tube) 21...Deflection section 22,200a,202a…Main lumens 23a to 23d, 24a, 25a, 26a, 27a, 27b, 28a, 28b, 201a, 201b, 204a, 204b... Wire lumen 29…Tip protection member 200, 202... Single lumen tube 201...Multi-lumen tube 203...Long members 3...Operation unit 31...Rotational operation member 32...Gripping part 4…Grip section 42...Holding part 5…Knob member W1~W13…Wire

Claims

1. A steerable catheter comprising a tube having a main lumen, The tube has a plurality of spaced apart wire lumens extending from a proximal end to a distal end of the tube, the wire lumens being disposed outside the main lumen, Approximately half of one end of the wire is inserted into one of the wire lumens, a middle portion of the wire is folded back at the distal end of the tube, and approximately half of the other end of the wire is inserted into the other one of the wire lumens, and the wire has one end and the other end disposed on the proximal end side of the tube, the one end and the other end of a first wire which is one of the at least two wires and a second wire which is the other of the at least two wires are connected to each other, the one end and the other end of each of the first wire and the second wire can be pulled simultaneously, and the one end and the other end of each of the first wire and the second wire can be loosened simultaneously, and when the one end and the other end of the first wire are pulled simultaneously, the one end and the other end of the second wire can be loosened simultaneously, and when the one end and the other end of the second wire are pulled simultaneously, the one end and the other end of the first wire can be loosened simultaneously, A movable catheter in which no current is passed through the first wire and the second wire.

2. 2. The steerable catheter according to claim 1, wherein three or more of the wire lumens are provided, and two or more of the wires are provided.

3. 3. The movable catheter according to claim 1, wherein the tube comprises a single-lumen tube having the main lumen, and at least one multi-lumen tube having a plurality of lumens for wires, integrally arranged on the outside of the single-lumen tube.

4. A steerable catheter comprising a tube having a main lumen, The tube has a wire lumen outside the main lumen, the wire lumen extending from the proximal end to the distal end of the tube; Approximately half of one end side of the wire is inserted into the wire lumen, a middle portion of the wire is folded back at the distal end side of the tube, approximately half of the other end side of the wire is passed outside the tube, and one end and the other end of the wire are disposed on the proximal end side of the tube, A movable catheter further comprising an operating unit to which one end and the other end of a first wire, which is one of the at least two wires, and a second wire, which is the other of the at least two wires, are connected, the one end and the other end of each of the first wire and the second wire can be pulled simultaneously, and the one end and the other end of each of the first wire and the second wire can be loosened simultaneously, and when the one end and the other end of the first wire are pulled simultaneously, the one end and the other end of the second wire can be loosened simultaneously, and when the one end and the other end of the second wire are pulled simultaneously, the one end and the other end of the first wire can be loosened simultaneously.

5. A steerable catheter comprising a tube having a main lumen, The tube has a wire lumen outside the main lumen, the wire lumen extending from the proximal end to the distal end of the tube; Approximately half of one end side of the wire is inserted into the wire lumen, a middle portion of the wire is folded back at the distal end side of the tube, and approximately half of the other end side of the wire is inserted into the main lumen, and one end and the other end side of the wire are disposed on the proximal end side of the tube. the one end and the other end of a first wire which is one of the at least two wires and a second wire which is the other of the at least two wires are connected to each other, the one end and the other end of each of the first wire and the second wire can be pulled simultaneously, and the one end and the other end of each of the first wire and the second wire can be loosened simultaneously, and when the one end and the other end of the first wire are pulled simultaneously, the one end and the other end of the second wire can be loosened simultaneously, and when the one end and the other end of the second wire are pulled simultaneously, the one end and the other end of the first wire can be loosened simultaneously, A movable catheter in which no current is passed through the first wire and the second wire.

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