Catheter

Abstract

Provided is a catheter that can be easily inserted into a curved section in a body. The catheter has: a first cylindrical member extending in the longitudinal direction; a second cylindrical member extending in the longitudinal direction and adjacent to the first cylindrical member in the radial direction; and an outer member that extends in the longitudinal direction and has a portion that encloses at least a portion of the first cylindrical member and at least a portion of the second cylindrical member, the distal end of the first cylindrical member being located closer to the location side than the distal end of the second cylindrical member, and the distal end of the second cylindrical member being located closer to the location side than the distal end of the second cylindrical member. The proximal end of the first cylindrical member is positioned further toward the proximal side than the proximal end of the second cylindrical member, and the distal end of the outer member is positioned further toward the distal side than the distal end of the second cylindrical member. A first thin portion that is located closer to the position side than the first thick portion and that is thinner than the first thick portion; and a second thick portion located closer to the position side than the first thin portion and thicker than the first thin portion.

Description

Technical Field

[0001] This invention relates to catheters. Background Technology

[0002] Catheters, which can be inserted into blood vessels, are used to examine or treat lesions in the human body. As such a conduit, for example, Patent Document 1 discloses a conduit characterized by comprising: a conduit body having a hollow spiral formed by winding or twisting a plurality of metal wires, at least one of which has a diameter greater than that of the other wires; an inner resin layer covering the inner circumferential surface of the spiral; and an outer resin layer covering the outer circumferential surface of the spiral in a substantially circular shape so that the outer surface of the larger diameter wires of the spiral is not exposed to the outside; a tip having an inner hole communicating with the hollow portion of the conduit body, and being composed of a resin-made cylindrical body disposed at the distal end of the conduit body; an inner layer extension portion, wherein the inner resin layer extends integrally from the distal end of the conduit body toward the tip to form an inner circumferential portion of the proximal end of the tip; and a braid formed by braiding a plurality of wires, wherein the inner layer extension portion and the inner resin layer of at least the distal end portion of the conduit body are respectively disposed in the tip and the inner resin layer of the conduit body, respectively, when positioned to extend axially across the boundary between the proximal end of the tip and the distal end of the conduit body.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2011-125737 Summary of the Invention

[0004] According to the inventors' research, in existing catheters, there are situations where it is difficult to insert the catheter into a curved portion of a blood vessel or the like. Specifically, it is known that when inserting the catheter into a target location further inside the curved portion of the body using a guidewire, the catheter is too curved, and the inner surface of the catheter easily comes into contact with the guidewire, resulting in difficulty in inserting the catheter. The present invention has been made in view of the above-mentioned situation, and its object is to provide a catheter with a curved portion that is easy to insert into the body.

[0005] The catheters described in the embodiments of the present invention that can solve the above-mentioned problems are as follows.

[0006] [1] A catheter having:

[0007] The first cylindrical component extends along its length.

[0008] The second cylindrical member extends along the aforementioned length direction and is radially adjacent to the aforementioned first cylindrical member; and

[0009] The outer component, extending along the aforementioned length direction, has a portion that encloses at least a portion of the first cylindrical component and at least a portion of the second cylindrical component.

[0010] in,

[0011] The distal end of the first cylindrical component is located closer to the position than the distal end of the second cylindrical component.

[0012] The proximal end of the first cylindrical component is located closer to the position side than the proximal end of the second cylindrical component.

[0013] The distal end of the aforementioned outer component is located on the distal side compared to the distal end of the aforementioned second cylindrical component.

[0014] The aforementioned outer component has:

[0015] First thick-walled section;

[0016] The first thin-walled portion is located closer to the side than the first thick-walled portion and is thinner than the first thick-walled portion; and

[0017] The second thick-walled portion is located closer to the side than the first thin-walled portion and is thicker than the first thin-walled portion.

[0018] According to the inventors' research, in catheters where the outer layer thins towards the distal end, excessive bending can occur when passing through a bend in the body. On the other hand, in the catheter according to the embodiment, the outer component has a first thick-walled portion, a first thin-walled portion, and a second thick-walled portion sequentially from the distal side, thereby preventing excessive bending of the distal end of the catheter. As a result, when inserting the catheter into the bend in the body using a guidewire, the contact between the inner surface of the catheter and the guidewire is reduced, thus making it easier to insert the catheter into the bend.

[0019] Furthermore, the preferred embodiment involves a catheter that is any one of the following [2] to

[15] .

[0020] [2] According to the catheter described in [1], wherein,

[0021] The aforementioned first thick-walled portion includes the aforementioned distal end of the aforementioned outer component.

[0022] [3] According to the catheter described in [1] or [2], wherein,

[0023] The first thick-walled portion is adjacent to the first thin-walled portion, and the first thin-walled portion is adjacent to the second thick-walled portion.

[0024] [4] According to any one of [1] to [3], the catheter described therein,

[0025] The second thick-walled portion has a portion that is thicker than the first thick-walled portion.

[0026] [5] According to any one of [1] to [4], the catheter described therein,

[0027] The aforementioned second thick-walled portion has a raised portion that protrudes in a direction away from the aforementioned second cylindrical component.

[0028] [6] According to any one of [1] to [5], the catheter, wherein,

[0029] The length of the first thin-walled portion in the length direction is longer than the length of the first thick-walled portion in the length direction.

[0030] [7] According to any one of [1] to [6], the catheter described therein,

[0031] The length of the first thin-walled portion in the length direction is longer than the length of the second thick-walled portion in the length direction.

[0032] [8] According to any one of [1] to [7], the catheter, wherein,

[0033] The second cylindrical component has an X-ray impermeability mark located at a position that is more distal to the proximal end of the first thin-walled portion and closer to the distal end.

[0034] [9] According to any one of [1] to [8], the catheter described therein,

[0035] The aforementioned first thick-walled portion has a portion that thins as it moves toward the distal end of the aforementioned outer component.

[0036]

[10] According to any one of [1] to [9], the catheter, wherein,

[0037] The aforementioned first thin-walled portion has:

[0038] Part One;

[0039] The second part, located closer to the side than the first part, is thinner than the first part; and

[0040] The third part is located closer to the side than the second part mentioned above, and is thicker than the second part mentioned above.

[0041]

[11] According to any one of [1] to

[10] , the catheter, wherein,

[0042] The aforementioned outer component has a column extending along the aforementioned length direction and comprising resin.

[0043] At least a portion of the first cylindrical component and at least a portion of the second cylindrical component are disposed within the column.

[0044]

[12] According to any one of [1] to

[10] , the catheter, wherein,

[0045] The outer component is cylindrical and has an inner cavity extending along the length direction. At least a portion of the first cylindrical component and at least a portion of the second cylindrical component are disposed in the inner cavity.

[0046]

[13] According to any one of [1] to

[12] , the catheter, wherein,

[0047] The aforementioned outer component has: a main body portion that encloses a portion of the first cylindrical component and a portion of the second cylindrical component; a first front end portion located at a position more distal than the main body portion and enclosing the distal end portion of the first cylindrical component; and a second front end portion located at a position more distal than the main body portion and enclosing the distal end portion of the second cylindrical component, wherein the second front end portion comprises a material different from the material comprised of the first front end portion and the main body portion.

[0048]

[14] According to any one of [1] to

[13] , the catheter, wherein,

[0049] The first cylindrical component and the second cylindrical component are fixed to each other in the radial direction.

[0050]

[15] According to any one of [1] to

[14] , the catheter, wherein,

[0051] A handle portion is provided at the proximal end of the first cylindrical component.

[0052] According to the present invention, the above-described structure enables the provision of a catheter with a curved portion that is easily inserted into the body. Attached Figure Description

[0053] Figure 1 This is a side view of the catheter according to the first embodiment.

[0054] Figure 2 yes Figure 1 A cross-sectional view of region R1 along its length.

[0055] Figure 3 yes Figure 1 A cross-sectional view of region R2 along its length.

[0056] Figure 4 It means to Figure 1 A schematic diagram illustrating an example of a catheter being inserted into a curved section of the body.

[0057] Figure 5 yes Figure 1 AA cross-sectional view of the catheter.

[0058] Figure 6 yes Figure 1A cross-sectional view along the length of a modified example of region R1.

[0059] Figure 7 This is a side view of the catheter according to the second embodiment.

[0060] Figure 8 yes Figure 7 A cross-sectional view of region R1 along its length.

[0061] Figure 9 yes Figure 7 A cross-sectional view of region R2 along its length.

[0062] Figure 10 yes Figure 7 AA cross-sectional view of the catheter. Detailed Implementation

[0063] The present invention will now be described in more detail based on the following embodiments. However, the present invention is not limited to these embodiments, and it is undoubtedly possible to implement it by appropriate modifications within the scope of the preceding / following descriptions, all of which are included within the technical scope of the present invention. Furthermore, in the various drawings, reference numerals for components may be omitted for convenience; in such cases, please refer to the specification and other drawings. Additionally, the dimensions of various components in the drawings are primarily advantageous for understanding the features of the present invention, and therefore may differ from the actual dimensions.

[0064] The catheter according to the embodiment includes: a first cylindrical member extending along a length direction; a second cylindrical member extending along a length direction and radially adjacent to the first cylindrical member; and an outer member extending along a length direction, having a portion that encloses at least a portion of the first cylindrical member and at least a portion of the second cylindrical member, wherein the distal end of the first cylindrical member is located closer to the position side than the distal end of the second cylindrical member, the proximal end of the first cylindrical member is located closer to the position side than the proximal end of the second cylindrical member, and the distal end of the outer member is located further to the position side than the distal end of the second cylindrical member. The outer member has: a first thick-walled portion; a first thin-walled portion located closer to the position side than the first thick-walled portion and thinner than the first thick-walled portion; and a second thick-walled portion located closer to the position side than the first thin-walled portion and thicker than the first thin-walled portion.

[0065] According to the inventors' research, in catheters where the outer layer thins towards the distal end, excessive bending can occur when passing through a bend in the body. On the other hand, in the catheter according to the embodiment, the outer component has a first thick-walled portion, a first thin-walled portion, and a second thick-walled portion sequentially from the distal side, thereby preventing excessive bending of the distal end of the catheter. As a result, when inserting the catheter into the bend in the body using a guidewire, the contact between the inner surface of the catheter and the guidewire is reduced, thus making it easier to insert the catheter into the bend.

[0066] The following is for reference Figures 1-6 The catheter involved in the first embodiment will be described. Figure 1 This is a side view of the catheter according to the first embodiment. Figure 2 yes Figure 1 A cross-sectional view of region R1 along its length. Figure 3 yes Figure 1 A cross-sectional view of region R2 along its length. Figure 4 It means to Figure 1 A schematic diagram illustrating an example of a catheter being inserted into a curved section of the body. Figure 5 yes Figure 1 AA cross-sectional view of the catheter. Figure 6 yes Figure 1 A cross-sectional view along the length of a modified example of region R1.

[0067] like Figure 1 , Figure 2 , Figure 3 As shown, the catheter 91 according to the first embodiment has: a first cylindrical member 1 extending along the length direction X; and a second cylindrical member 2 extending along the length direction X and adjacent to the first cylindrical member 1 in the radial direction Y. Specifically, it is preferable that the outer surface of the first cylindrical member 1 and the outer surface of the second cylindrical member 2 are adjacent to each other in the radial direction Y. Preferably, the first cylindrical member 1 has an inner lumen 1L extending along the length direction X. Preferably, the second cylindrical member 2 has an inner lumen 2L extending along the length direction X. By inserting, for example, a guidewire into each of the inner lumen 1L and the inner lumen 2L, the catheter 91 can be guided in multiple directions, thus making it easy, for example, to insert the catheter 91 into various branches of the coronary artery. In addition, by inserting a exploratory wire into the inner lumen 1L or the inner lumen 2L, the entrance to the lesion, i.e., the stenosis, can be easily explored. It is preferable to insert the exploratory wire into the inner lumen 1L. The tip of the exploratory wire can be bent.

[0068] Preferably, the first cylindrical component 1 and the second cylindrical component 2 each have one or more layers extending along the length direction X, more preferably multiple layers. Preferably, the multiple layers have an inner layer and an outer layer that encloses at least a portion of the inner layer. The multiple layers may also have an intermediate layer located between the inner and outer layers. The number of intermediate layers is not limited to one, but may be two or more. Preferably, each of the multiple layers comprises a material different from that of adjacent layers. Preferably, the inner layer of the first cylindrical component 1 and the inner layer of the second cylindrical component 2 each comprise at least one resin selected from the group consisting of polyolefin resins and fluorinated resins. This improves the slippage of the guidewire inserted into the inner lumens 1L and 2L. The polyolefin resin is preferably polyethylene, polypropylene, ethylene-propylene copolymer, or mixtures thereof. Polyethylene is preferably high-density polyethylene with a specific gravity of 0.942 or higher. The fluorinated resin is preferably polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, ethylene-chlorotrifluoroethylene copolymer, or mixtures thereof. The inner layer of the first cylindrical component 1 and the inner layer of the second cylindrical component 2 may each comprise at least one resin selected from the group consisting of polyamide resin, polyester resin, polyurethane resin, polyolefin resin, fluorine resin, vinyl chloride resin, silicone resin, and natural rubber. The inner layers of the first cylindrical component 1 and the second cylindrical component 2 may comprise different resins, preferably the same resin, and more preferably composed of the same resin.

[0069] Preferably, the outer layers of the first cylindrical component 1 and the second cylindrical component 2 each comprise a flexible resin. The flexible resin preferably comprises at least one selected from the group consisting of polyethylene, polyurethane, polyurethane-based thermoplastic elastomers, styrene-based thermoplastic elastomers, polyamide elastomers, and polyamides; more preferably, it comprises at least one selected from the group consisting of polyurethane and polyamide elastomers. The polyethylene is preferably low-density polyethylene with a specific gravity of 0.91 to 0.92.

[0070] The Shore D hardness of the outer layer material is preferably less than or equal to that of the inner layer material, and more preferably less than that of the inner layer material. This improves the flexibility of the conduit 91. The Shore D hardness can be measured, for example, using a Type D hardness tester according to ISO 7619.

[0071] The intermediate layer preferably comprises a material different from the inner or outer layer, but may also comprise the same material as the inner or outer layer.

[0072] Preferably, the inner, middle, and outer layers are fixed to adjacent layers. This prevents the layers from twisting or turning. Examples of fixing methods include welding and bonding.

[0073] Preferably, the first cylindrical component 1 has a reinforcing member. This easily prevents the metal wire from puncturing the first cylindrical component 1. Preferably, the second cylindrical component 2 does not have a reinforcing member. This easily improves the flexibility of the second cylindrical component 2.

[0074] The reinforcing component is preferably a braided body made of braided wire, a spiral body made of helically wound wire, or a combination thereof. This easily prevents the guide wire from puncturing the first cylindrical component 1. The braided structure improves rigidity, therefore a braided body is more preferred as the reinforcing component. Examples of wires included in the reinforcing component include metal wires and fibers. The metal wires preferably include stainless steel, titanium, nickel-titanium alloys, cobalt-chromium alloys, tungsten alloys, or alloys thereof. Stainless steel is more preferred. The metal wire can be a single wire or a stranded wire. As for the fiber, polyaramid fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, PBO fiber, carbon fiber, or blends thereof are preferred. The fiber can be a monofilament or a multifilament. To facilitate confirmation of the position of the first cylindrical component 1 under X-ray fluoroscopy, the reinforcing component may also include an X-ray-impermeable material. The X-ray-impermeable material is preferably at least one selected from the group consisting of lead, barium, iodine, tungsten, gold, platinum, iridium, platinum-iridium alloys, stainless steel, titanium, cobalt-chromium alloys, palladium, bismuth, and tantalum.

[0075] Although not illustrated, it is preferable that the distal end of the reinforcing member is located closer to the proximal end of the first opening 1E and more distal to the proximal end 2A of the second cylindrical member 2. On the other hand, it is preferable that the proximal end of the reinforcing member is located closer to the proximal end 2A of the second cylindrical member 2, and more preferably located within the handle portion 8. This makes it easier to prevent the guide wire from puncturing the first cylindrical member 1.

[0076] like Figure 5 As shown, the outer surface of the first cylindrical component 1 and the outer surface of the second cylindrical component 2 may not contact each other, or they may contact each other and be fixed together. Examples of fixing methods include welding and bonding. When the outer surface of the first cylindrical component 1 and the outer surface of the second cylindrical component 2 do not contact each other, they are preferably fixed together by the resin of the outer component 3. Furthermore, as... Figure 5 As shown, preferably, in the radial Y-section of the conduit 91, the shapes of the first inner lumen 1L and the second inner lumen 2L are circular, elliptical, arc-shaped, or a combination thereof, more preferably circular or elliptical. This allows the conduit 91 to be easily bent. Preferably, the first inner lumen 1L and the second inner lumen 2L are not connected within the conduit 91. In the radial Y-section, the area of ​​the first inner lumen 1L can be larger than, smaller than, or the same as the area of ​​the second inner lumen 2L.

[0077] like Figure 2As shown, the distal end 1B of the first cylindrical member 1 is located closer to the distal end 2B of the second cylindrical member 2. This improves the flexibility of the portion of the catheter 91 that is more distal to the distal end 1B of the first cylindrical member 1.

[0078] like Figure 1 , Figure 3 As shown, the proximal end 1A of the first cylindrical member 1 is located closer to the position than the proximal end 2A of the second cylindrical member 2. Therefore, the portion of the catheter 91 closer to the position than the proximal end 2A of the second cylindrical member 2 can be configured as, for example, a double-walled tube structure (coaxial structure), forming a different structure from the structure where the first cylindrical member 1 and the second cylindrical member 2 overlap radially in the Y direction, and thus can perform different functions.

[0079] like Figure 2 , Figure 3 , Figure 5 As shown, the catheter 91 has an outer component 3 extending along the length direction X, having a portion that encloses at least a portion of the first cylindrical component 1 and at least a portion of the second cylindrical component 2. The outer component 3 protects the first cylindrical component 1 and the second cylindrical component 2, and easily prevents the guidewire from puncturing from the inside of the catheter 91.

[0080] The outer component 3 preferably comprises at least one selected from the group consisting of polyethylene, polyurethane, polyurethane-based thermoplastic elastomers, styrene-based thermoplastic elastomers, polyamide elastomers, and polyamides. More preferably, it comprises at least one selected from the group consisting of polyurethane and polyamide elastomers.

[0081] like Figure 5 As shown, the outer component 3 preferably has a column 5 extending along the length direction X and comprising resin, with at least a portion of the first cylindrical component 1 and at least a portion of the second cylindrical component 2 disposed within the column 5. That is, preferably, at least a portion of the first cylindrical component 1 and the second cylindrical component 2 are sealed by the column 5 extending along the length direction X and comprising resin. Thus, even if the conduit 91 is bent, the shape of the inner cavities 1L and 2L extending along the length direction X is easily maintained. Preferably, the column 5 is disposed at least between the proximal end 2A and the distal end 2B of the second cylindrical component 2. Furthermore, the resin of the column 5 may also be present between the first cylindrical component 1 and the second cylindrical component 2.

[0082] The shape of the column 5 is preferably cylindrical, elliptical, or rounded polygonal, and more preferably cylindrical or elliptical. This makes it easy to insert the catheter 91 into the body.

[0083] The column 5 can be formed by fitting a resin tube onto the first cylindrical component 1 and the second cylindrical component 2 that overlap in the radial Y direction and then heating and welding them together, or by injection molding the first cylindrical component 1 and the second cylindrical component 2 that overlap in the radial Y direction.

[0084] like Figure 2 As shown, the distal end 3B of the outer component 3 is located further distally than the distal end 2B of the second cylindrical component 2. With this configuration, the first thick-walled portion T1 of the outer component 3 can be easily formed.

[0085] Preferably, at least a portion of the inner surface of the outer component 3 is fixed to the outer surface of the first cylindrical component 1 and the second cylindrical component 2. This prevents the outer component 3 from easily twisting or turning. Examples of fixing methods include welding and bonding.

[0086] The outer component 3 has: a first thick-walled portion T1; a first thin-walled portion U1 located closer to the position side than the first thick-walled portion T1 and thinner than the first thick-walled portion T1; and a second thick-walled portion T2 located closer to the position side than the first thin-walled portion U1 and thicker than the first thin-walled portion U1. This prevents excessive bending of the distal end of the conduit 91. For example, as... Figure 4 As shown, excessive bending can be prevented when the guidewire 9 is inserted into the lumen 2L of the second cylindrical member 2 and the catheter 91 is inserted into the bend 99 of the guidewire 9 into the body. As a result, the contact between the inner surface of the catheter 91 and the guidewire 9 is reduced, thus making it easier for the catheter 91 to be inserted into the bend 99 of the body. For example, an artery such as a coronary artery can be used as the bend 99 in the body.

[0087] like Figure 2 As shown, it is preferable that the thickness relationship of the first thick-walled portion T1, the first thin-walled portion U1, and the second thick-walled portion T2 is satisfied in the cross section (hereinafter referred to as "section X") along the longitudinal direction X including the central axis 1C of the first cylindrical member 1 and the central axis 2C of the second cylindrical member 2. Specifically, in section X, the outer member 3 has a first region 31 on the side closer to the first cylindrical member 1 in the radial Y direction and a second region 32 on the side away from the first cylindrical member 1 in the portion adjacent to the second cylindrical member 2, and preferably the thickness relationship is satisfied at least in the first region 31. This makes it easy to prevent excessive bending in the direction from the second region 32 toward the first region 31. Moreover, although not shown, it is more preferable that the thickness relationship is satisfied in the first region 31 and the second region 32 respectively. This makes it easy to prevent excessive bending in the direction from the first region 31 toward the second region 32 and in the direction from the second region 32 toward the first region 31.

[0088] Preferably, the first thick-walled portion T1 includes the distal end 3B of the outer member 3. This easily prevents excessive bending of the distal end 3B of the outer member 3 and its vicinity. More preferably, the first thick-walled portion T1 is located distally to the distal end 2B of the second cylindrical member 2. This allows the first thick-walled portion T1 to bend to a certain extent.

[0089] Preferably, the first thick-walled portion T1 is adjacent to the first thin-walled portion U1, and the first thin-walled portion U1 is adjacent to the second thick-walled portion T2. ​​As a result, the first thick-walled portion T1, the first thin-walled portion U1, and the second thick-walled portion T2 can be easily bent as a whole, and excessive bending can be easily prevented.

[0090] Preferably, the second thick-walled portion T2 has a portion that is thicker than the first thick-walled portion T1. This improves the pushing performance.

[0091] Preferably, the second thick-walled portion T2 has a raised portion T2p that bulges away from the second cylindrical member 2. Although not shown, for example, by bringing a wire inserted from the proximal side of the first cylindrical member 1 into contact with the raised portion T2p, the tip of the wire can be guided in a different direction than the tip of the wire inserted into the second cylindrical member 2, thus facilitating treatment of various branch lesions, etc. Furthermore, this prevents the individual wires from tangling. Preferably, the raised portion T2p is adjacent to the distal end 1B of the first cylindrical member 1. This facilitates the guidance of the wire emerging from the first opening 1E through the raised portion T2p.

[0092] Preferably, the raised portion T2p has a first inclined portion and a second inclined portion in cross-section X. The first inclined portion is inclined in a direction that moves away from the central axis 2C of the second cylindrical member 2 as it moves toward the distal side, and the second inclined portion is inclined in a manner that moves closer to the central axis 2C of the second cylindrical member 2 as it moves toward the distal side. Preferably, the second inclined portion is located more distally than the first inclined portion. The second inclined portion allows for easy insertion of the catheter 91 into the body. The first inclined portion allows for easy changing of the orientation of the wire inserted from the proximal side of the first cylindrical member 1.

[0093] Preferably, the raised portion T2p is located within the first region 31 of the outer component 3. This makes it easy to prevent excessive bending in the direction from the second region 32 toward the first region 31.

[0094] Preferably, the length of the first thin-walled portion U1 in the longitudinal direction X is longer than the length of the first thick-walled portion T1 in the longitudinal direction X. This makes the first thin-walled portion U1 easier to bend overall, thus easily preventing localized bending of the first thin-walled portion U1. The length of the first thin-walled portion U1 in the longitudinal direction X is preferably 1.5 times or more and 8 times or less, more preferably 2.0 times or more and 5 times or less, than the length of the first thick-walled portion T1 in the longitudinal direction X. The length of the first thin-walled portion U1 in the longitudinal direction X is preferably 2 mm or more and 8 mm or less, more preferably 3 mm or more and 6 mm or less. Preferably, the first thin-walled portion U1 does not have an inclined portion that slopes away from the central axis 2C of the second cylindrical member 2 in a direction toward the distal end 3B of the outer member 3. This makes the first thin-walled portion U1 easier to bend overall.

[0095] Preferably, the length of the first thin-walled portion U1 in the longitudinal direction X is longer than the length of the second thick-walled portion T2 in the longitudinal direction X. This makes the first thin-walled portion U1 easier to bend overall, thus easily preventing localized bending of the first thin-walled portion U1. The length of the first thin-walled portion U1 in the longitudinal direction X is preferably 1.5 times or more and 6 times or less than the length of the second thick-walled portion T2 in the longitudinal direction X, more preferably 2.0 times or more and 3 times or less.

[0096] Preferably, the second cylindrical component 2 has an X-ray impermeability mark 6B, which is located distal to the proximal end U1A of the first thin-walled portion U1 and closer to the distal end U1B. This makes it easier to determine the position of the bend in the catheter 91 when inserting it into the curved portion 99 within the body, thus facilitating insertion. Furthermore, this also helps to prevent excessive bending of the first thin-walled portion U1.

[0097] The X-ray impermeability mark is preferably ring-shaped. Preferably, the X-ray impermeability mark includes an X-ray impermeable material, more preferably it is composed of an X-ray impermeable material. The X-ray impermeable material is preferably at least one selected from the group consisting of lead, barium, iodine, tungsten, gold, platinum, iridium, platinum-iridium alloys, stainless steel, titanium, cobalt-chromium alloys, palladium, bismuth, and tantalum.

[0098] Preferably, the first thick-walled portion T1 has a portion T1u that thins towards the distal end 3B of the outer component 3. This facilitates the insertion of the first thick-walled portion T1 into the body. The shape of the outer surface of the portion T1u in section X is preferably straight or curved, more preferably straight. When the outer surface is straight, the portion T1u is so-called conical.

[0099] exist Figure 2In this configuration, the inner diameter of the outer component 3, which is located distal to the distal end 2B of the second cylindrical component 2, is the same length as the inner diameter of the distal end 2B of the second cylindrical component 2. However, the inner diameter of the outer component 3, which is located distal to the distal end 2B, can also be longer than the inner diameter of the distal end 2B of the second cylindrical component 2. As a result, the first thick-walled portion T1 is less likely to come into contact with the guide wire 9 on its inner surface.

[0100] Preferably, the first thin-walled portion U1 has: a first portion U11; a second portion U12, located closer to the position than the first portion U11 and thinner than the first portion U11; and a third portion U13, located closer to the position than the second portion U12 and thicker than the second portion U12. By comparing the thickness of the first portion U11 and the third portion U13, excessive bending of the first thin-walled portion U1 can be easily prevented.

[0101] Preferably, the first part U11 is adjacent to the second part U12, and the second part U12 is adjacent to the third part U13. Therefore, the first part U11, the second part U12 and the third part U13 can be bent as a whole, and excessive bending can be easily prevented.

[0102] like Figure 2 As shown, it is preferable that the thickness relationship of the first part U11, the second part U12, and the third part U13 described above is satisfied in cross section X. Specifically, in cross section X, it is preferable that the thickness relationship described above is satisfied at least in the first region 31. This makes it easy to prevent excessive bending in the direction from the second region 32 toward the first region 31. More preferably, the thickness relationship described above is satisfied in both the first region 31 and the second region 32. This makes it easy to prevent excessive bending of the first thin-walled portion U1 in both the direction from the first region 31 toward the second region 32 and the direction from the second region 32 toward the first region 31.

[0103] like Figure 6 As shown, the preferred outer component 3 preferably has: a main body 33, which encloses a portion of the first cylindrical component 1 and a portion of the second cylindrical component 2; a first front end portion 34, located distal to the main body 33 and enclosing the distal end portion 1b of the first cylindrical component 1; and a second front end portion 35, located distal to the main body 33 and enclosing the distal end portion 2b of the second cylindrical component 2. More preferably, the second front end portion 35 comprises a material different from that included in the first front end portion 34 and the main body 33. For example, by including a material softer than that included in the first front end portion 34 and the main body 33 in the second front end portion 35, damage to biological tissue by the tip of the catheter 91 can be easily avoided. Furthermore, in Figure 6 The diagram shows the dividing line between the main body 33 and the first front end 34, but the dividing line can also disappear due to welding.

[0104] like Figure 2As shown, the first cylindrical component 1 preferably has a first opening 1E communicating with the inner cavity 1L. The first opening 1E can be used as the inlet or outlet of the guide wire 9.

[0105] like Figure 2 As shown, the second cylindrical component 2 preferably has a second opening 2E communicating with the inner cavity 2L. The second opening 2E can be used as the inlet or outlet of the guide wire 9.

[0106] like Figure 1 As shown, a handle portion 8 is preferably disposed at the proximal end 1a of the first cylindrical member 1. Specifically, the proximal end 1a of the first cylindrical member 1 is preferably disposed within the handle portion 8. The surgeon can insert the catheter 91 into the body by holding and pressing the handle portion 8. The shape of the handle portion 8 is only required to be one that the surgeon can hold with his / her fingers. The handle portion 8 is preferably a resin molded part obtained by injection molding or the like. Examples of resins include polyolefin resins such as polyethylene and polypropylene, polycarbonate resins, and (meth)acrylic resins. Transparent resins such as polycarbonate and polymethyl methacrylate are preferred. This makes it easy to see the interior of the handle portion 8 and allows for easy insertion of a metal wire.

[0107] Preferably, the proximal end 1A of the first cylindrical member 1 is located inside the handle portion 8. This improves the pushing performance.

[0108] Preferably, the handle portion 8 has an inner cavity that communicates with the inner cavity 1L of the first cylindrical component 1 and extends along the length direction X, through which the guide wire 9 can be inserted.

[0109] like Figure 1 , Figure 3 As shown, the preferred catheter 91 further includes an outer cylindrical member 4 extending along the length direction X. The preferred outer cylindrical member 4 has an inner cavity 4L extending along the length direction X, in which a portion of the first cylindrical member 1 is disposed. The outer cylindrical member 4 allows for a double-layered tube structure (coaxial structure), improving the transmission of insertion force while protecting the first cylindrical member 1. Specifically, the preferred outer cylindrical member 4 has a fixing portion fixed to the first cylindrical member 1 at its distal end and a non-fixed portion not fixed to the first cylindrical member 1 at a position closer to the fixing portion. Additionally, the preferred outer cylindrical member 4 has a fixing portion fixed to the handle portion 8 at its proximal end.

[0110] Preferably, the outer cylindrical member 4 is located closer to the position side than the proximal end 2A of the second cylindrical member 2. This allows for a reduction in the outer diameter of the outer cylindrical member 4.

[0111] The outer cylindrical component 4 preferably comprises the same resin as the outer component 3 or a harder resin, more preferably a harder resin. A harder resin can improve the pushability. Furthermore, it is preferable that the distal end of the outer cylindrical component 4 and the proximal end of the outer component 3 are fixed to each other.

[0112] like Figure 2 As shown, the first cylindrical component 1 may also have an X-ray opacity mark 6A located closer to the proximal end of the first opening 1E and more distal to the proximal end of the first opening 1E. This allows for easy determination of the position of the first opening 1E. The X-ray opacity mark 6A preferably comprises the same material as the X-ray opacity mark 6B, and more preferably is made of the same material as the X-ray opacity mark 6B. The shape of the X-ray opacity mark 6A may also be different from that of the X-ray opacity mark 6B, but is preferably the same.

[0113] Although not illustrated, the preferred conduit 91 also includes a linear component extending along the length direction X, with at least a portion disposed within the outer cylindrical component 4. This improves the transmission of the insertion force. The linear component is preferably straight. There may be one or more linear components. Preferably, the proximal end of the linear component is located within the handle portion 8. Preferably, the distal end of the linear component is located inside the outer cylindrical component 4 or the outer component 3. The linear component is preferably a solid component without an internal cavity. The linear component preferably comprises metal, more preferably is made of metal. The metal is preferably stainless steel, nickel-titanium, cobalt-chromium, or alloys thereof. Preferably, the linear component has a shaped portion extending along the length direction X and having the same radial cross-sectional shape. More preferably, the linear component also has a tapered portion located distal to the shaped portion and tapering towards the distal side.

[0114] The catheter 91 is preferably used for the treatment of narrowing or blockage in blood vessels or other pathways within the body, and more preferably for use in the administration of percutaneous coronary intervention (PCI) for lesions in the branches of coronary arteries.

[0115] The following is for reference Figures 7-10 The catheter involved in the second embodiment will be described. Figure 7 This is a side view of the catheter according to the second embodiment. Figure 8 yes Figure 7 A cross-sectional view of region R1 along its length. Figure 9 yes Figure 7 A cross-sectional view of region R2 along its length. Figure 10 yes Figure 7 A cross-sectional view of the catheter (AA section). Detailed descriptions of portions that overlap with those of the catheter described in the first embodiment are omitted.

[0116] The conduit involved in the second embodiment is a conduit 92 having a first cylindrical member 1 extending in the length direction X, a second cylindrical member 2 extending in the length direction X and adjacent to the first cylindrical member 1 in the radial direction Y, and an outer member 3 extending in the length direction X and having a portion that encloses at least a portion of the first cylindrical member 1 and at least a portion of the second cylindrical member 2. For details of each part, please refer to the description of the conduit 91.

[0117] like Figures 7-10 As shown, in the catheter 92, the outermost component 3 is preferably cylindrical, having an inner cavity 3L extending along the length direction X. At least a portion of the first cylindrical component 1 and at least a portion of the second cylindrical component 2 are disposed in the inner cavity 3L. This protects the first cylindrical component 1 and the second cylindrical component 2, and allows each cylindrical component to move to a certain extent through the gaps between the outermost component 3 and the first cylindrical component 1, and between the outermost component 3 and the second cylindrical component 2, thereby releasing the force from the guidewire 9 inside the catheter 92, resulting in easy prevention of guidewire 9 puncture. Preferably, the distal end of the cylindrical outermost component 3 is fixed to the first cylindrical component 1 and the second cylindrical component 2. Preferably, the proximal end of the cylindrical outermost component 3 is fixed to the first cylindrical component 1 and the second cylindrical component 2. This prevents the cylindrical outermost component 3 from twisting or turning.

[0118] In the conduit 92, the first cylindrical component 1 and the second cylindrical component 2 are preferably fixed to each other in the radial direction Y. Specifically, the outer surfaces of the first cylindrical component 1 and the second cylindrical component 2 are preferably fixed to each other in the radial direction Y. This prevents the second cylindrical component 2 from twisting or turning. Examples of fixing methods include welding and bonding.

[0119] This application claims a benefit based on priority of Japanese Patent Application No. 2023-125555, filed August 1, 2023. The entire contents of the description of Japanese Patent Application No. 2023-125555, filed August 1, 2023, are incorporated herein by reference.

[0120] Explanation of reference numerals in the attached figures

[0121] 1…First cylindrical component; 1a…Proximal end; 1b…Distal end; 1A…Proximal end; 1B…Distal end; 1C…Central axis; 1E…First opening; 1L…Cavity; 2…Second cylindrical component; 2b…Distal end; 2A…Proximal end; 2B…Distal end; 2C…Central axis; 2E…Second opening; 2L…Cavity; 3…Outer component; 3B…Distal end; 3L…Cavity; 4…Outer cylindrical component; 4L…Cavity; 5…Column; 6A, 6B…X-ray impermeability Marker; 8…Handle portion; 9…Guidewire; 31…First region; 32…Second region; 33…Main body portion; 34…First front end portion; 35…Second front end portion; 91, 92…Catheter; 99…Bend portion; T1…First thick-walled portion; T1u…Thinned portion; T2…Second thick-walled portion; T2p…Raised portion; U1…First thin-walled portion; U11…First part; U12…Second part; U13…Third part; U1A…Proximal end; U1B…Distal end; X…Length direction; Y…Radial direction.

Claims

1. A catheter having: The first cylindrical component extends along its length. A second cylindrical member extends along the length direction and is radially adjacent to the first cylindrical member; and The outer component, extending along the length direction, has a portion that encloses at least a portion of the first cylindrical component and at least a portion of the second cylindrical component. The catheter is characterized in that, The distal end of the first cylindrical component is located closer to the position than the distal end of the second cylindrical component. The proximal end of the first cylindrical component is located closer to the position side than the proximal end of the second cylindrical component. The distal end of the outer component is located on a more distal side than the distal end of the second cylindrical component. The outer component has: First thick-walled section; The first thin-walled portion is located closer to the side than the first thick-walled portion and is thinner than the first thick-walled portion; and The second thick-walled portion is located closer to the side than the first thin-walled portion and is thicker than the first thin-walled portion.

2. The catheter according to claim 1, characterized in that, The first thick-walled portion includes the distal end of the outer component.

3. The catheter according to claim 1, characterized in that, The first thick-walled portion is adjacent to the first thin-walled portion, and the first thin-walled portion is adjacent to the second thick-walled portion.

4. The catheter according to claim 1, characterized in that, The second thick-walled portion has a portion that is thicker than the first thick-walled portion.

5. The catheter according to claim 1, characterized in that, The second thick-walled portion has a raised portion that protrudes in a direction away from the second cylindrical member.

6. The catheter according to claim 1, characterized in that, The length of the first thin-walled portion in the length direction is longer than the length of the first thick-walled portion in the length direction.

7. The catheter according to claim 1, characterized in that, The length of the first thin-walled portion in the length direction is longer than the length of the second thick-walled portion in the length direction.

8. The catheter according to claim 1, characterized in that, The second cylindrical component has an X-ray impermeability mark located at a position that is more distal to the proximal end of the first thin-walled portion and closer to the distal end.

9. The catheter according to claim 1, characterized in that, The first thick-walled portion has a portion that thins as it moves toward the distal end of the outer component.

10. The catheter according to claim 1, characterized in that, The first thin-walled portion has: Part One; The second part, located closer to the side than the first part, is thinner than the first part; and The third part is located closer to the side than the second part and is thicker than the second part.

11. The catheter according to claim 1, characterized in that, The outer component has a column extending along the length direction and comprising resin. At least a portion of the first cylindrical member and at least a portion of the second cylindrical member are disposed within the column.

12. The catheter according to claim 1, characterized in that, The outer component is cylindrical and has an inner cavity extending along the length direction, in which at least a portion of the first cylindrical component and at least a portion of the second cylindrical component are disposed.

13. The catheter according to claim 1, characterized in that, The outer component has: a main body portion that encloses a portion of the first cylindrical component and a portion of the second cylindrical component; a first front end portion located distal to the main body portion and enclosing the distal end portion of the first cylindrical component; and a second front end portion located distal to the main body portion and enclosing the distal end portion of the second cylindrical component, the second front end portion comprising a material different from the material comprising the first front end portion and the main body portion.

14. The catheter according to claim 1, characterized in that, The first cylindrical component and the second cylindrical component are fixed to each other in the radial direction.

15. The catheter according to claim 1, characterized in that, A handle is provided at the proximal end of the first cylindrical component.

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