Catheter and method for producing same

Abstract

Provided is a catheter that has both flexibility, and rigidity which enables pushing-in force to be transmitted from an operator side to a tip side thereof.　The catheter has a cylindrical member which has a lumen extending in a longitudinal-axis direction. The catheter has a braided tube or a coil positioned on the outside in the radial direction of the cylindrical member, and in a partial section of the braided tube or the coil in the longitudinal axis direction, a belt-shaped body formed from a resin is arranged spirally more on the outside in the radial direction than the braided tube or the coil.

Description

Catheter and method for manufacturing same

[0001] The present invention relates to a catheter and a method for manufacturing the same.

[0002] Various catheters are used in medical settings. By inserting a catheter into a blood vessel or body cavity and reaching the catheter's tip to the target location, treatments and diagnoses, such as administering or injecting drugs or contrast agents, can be performed. To insert a catheter into a blood vessel or body cavity, the catheter must be highly adaptable to the shape of the blood vessel or body cavity, and the catheter's tip, in particular, must be flexible. On the other hand, to navigate the catheter within a blood vessel or body cavity, the catheter must be able to transmit a pushing force (pushability) from the proximal side to the tip. Thus, catheters must be flexible and rigid enough to transmit a pushing force from the proximal side to the tip.

[0003] For example, Patent Document 1 discloses an example of such a catheter, a medical device including a medical tubing section at least a portion of which is inserted into a living body and which has a lumen that functions as a passageway during use. This medical device includes a tubular first reinforcing body that extends axially at the portion of the medical tubing that is inserted into the living body, with its distal end located midway along the axial direction of the medical tubing section, and that constitutes a tubular wall section of the medical tubing section along its extending range. The first reinforcing body has a reduced-rigidity region formed in a predetermined region extending from the distal end toward the proximal side, which region has reduced rigidity compared to the proximal side. The medical device also includes a tubular second reinforcing body that extends from a position proximal to the distal end of the first reinforcing body to a position distal to the first reinforcing body and that constitutes the tubular wall section along its extending range. The second reinforcing body extends distally from the lumen of the first reinforcing body.

[0004] JP 2012-45043 A

[0005] Patent Document 1 describes that a joint ring 42 is provided as a first reinforcing body for the outer pipe portion 31, and that a spiral slit 55 is formed in the joint ring 42 as a rigidity reducing structure. However, the rigidity of the joint ring 42 is not reduced by simply forming the spiral slit 55, and it is difficult to ensure flexibility.

[0006] The present invention was made in light of the above-mentioned circumstances, and its purpose is to provide a catheter that combines flexibility with rigidity that allows the pushing force from the proximal side to be transmitted to the distal side, and a method for manufacturing the same.

[0007] The present invention is as follows: [1] A catheter having a tubular member with a lumen extending in the longitudinal direction, the catheter including a braided tube or a coil located radially outward of the tubular member, and a resin band arranged spirally radially outward of the braided tube or the coil in a partial section of the braided tube or the coil in the longitudinal direction. [2] The catheter according to [1], including a resin layer located radially outward of the braided tube or the coil and radially inward of the band, the Shore D hardness of the band being greater than the Shore D hardness of the resin layer. [3] The catheter according to [1] or [2], wherein, in a side view of the catheter, there are gaps between adjacent bands. [4] The catheter according to [3], wherein, in a side view of the catheter, when the width of the band-shaped body in the longitudinal axis direction of the tubular member is L1 and the distance between the gaps between adjacent band-shaped bodies is L2, the width L1 and the distance L2 between the gaps satisfy the relationship expressed by the following formula (1): L2≦L1 ... (1) [5] The catheter according to any of [1] to [4], wherein the braided tube has wires, and the wires have inclined portions that are inclined with respect to the longitudinal axis direction of the tubular member, and the catheter satisfies the relationship expressed by the following formula (2) in a side view of the catheter: θ1 ≠ θ2 ... (2) [In formula (2), θ1 represents the angle between the longitudinal axis direction of the tubular member and the inclination direction of the band-shaped body. θ2 represents the angle between the longitudinal axis direction of the tubular member and the inclination direction of the wires. [6] The catheter according to [5], wherein the absolute value of the difference between θ1 and θ2 is greater than 0° and equal to or less than 65°. [7] The catheter according to any one of [1] to [6], wherein the coil has an inclined portion inclined with respect to the longitudinal axis direction of the tubular member, and satisfies the relationship expressed by the following formula (3) in a side view of the catheter: θ1 ≠ θ3 ... (3) [In formula (3), θ1 represents the angle between the longitudinal axis direction of the tubular member and the inclination direction of the band-shaped body. θ3 represents the angle between the longitudinal axis direction of the tubular member and the inclination direction of the coil.[8] The catheter according to [7], wherein the absolute value of the difference between θ1 and θ3 is greater than 0° and equal to or less than 65°. [9] The catheter according to any of [1] to [8], wherein the band is disposed at a proximal end of the braided tube or the coil in the longitudinal axis direction of the tubular member.

[10] The catheter according to any of [1] to [9], further comprising a linear member fixed to the tubular member and extending proximally from the tubular member, and wherein the catheter is an extension catheter having a lumen extending in the longitudinal axis direction of the tubular member, the second catheter having an opening at its distal end, and capable of being inserted into the second catheter and protruding from the opening.

[11] A method for manufacturing a catheter, comprising: a step of disposing a braided tube or a coil radially outside a tubular member having a lumen extending in the longitudinal axis direction; and a step of disposing a resin band spirally radially outside the braided tube or the coil.

[12] The manufacturing method according to

[11] , further comprising, between the step of arranging the braided tube or coil and the step of spirally arranging the resin strip, a step of arranging a resin layer radially outward of the braided tube or the coil.

[13] The manufacturing method according to

[11] or

[12] , wherein, in the step of spirally arranging the strip, a force is applied in a direction separating one end of the strip from the other end.

[0008] The catheter according to the present invention has a tubular member and a braided tube or coil radially outside the tubular member. Furthermore, a resin band is spirally arranged on a portion radially outside the braided tube or coil, providing a catheter that combines flexibility with rigidity sufficient to transmit a pushing force from the proximal side to the distal side. The present invention also provides a method for manufacturing such a catheter.

[0009] Fig. 1 is a side view showing an embodiment of a catheter. Fig. 2 is a partially enlarged view of Fig. 1. Fig. 3 is a partially enlarged view of Fig. 1 when a coil is used instead of the braided tube. Fig. 4 is a side view showing another embodiment of a catheter. Fig. 5 is a side view showing the catheter shown in Fig. 4 inserted into a second catheter with a portion protruding from an opening at the distal end of the second catheter.

[0010] An embodiment of a catheter according to the present invention is a catheter having a tubular member with an inner cavity extending in the longitudinal direction, and a braided tube or coil located radially outside the tubular member, and a resin band-shaped body is spirally arranged radially outside the braided tube or coil in a section of the braided tube or coil in the longitudinal direction.

[0011] The present invention will be described in more detail below based on the embodiments, but the present invention is not limited to the following embodiments. Of course, modifications can be made within the scope of the above and below-described purposes, and all such modifications are included within the technical scope of the present invention. For convenience, hatching and component symbols may be omitted in the drawings. In such cases, reference should be made to the specification and other drawings. The dimensions of various components in the drawings may differ from actual dimensions, as priority is given to helping understand the features of the present invention.

[0012] In this specification, the proximal side refers to the direction toward the user in the longitudinal direction, and the distal side refers to the opposite side of the proximal side, i.e., the direction toward the treatment target. Furthermore, when each component is divided into two equal parts along the longitudinal axis, the distal portion of each component is referred to as the distal section, and the proximal portion of each component is referred to as the proximal section. The distal end of each component is the most distal end of each component, and the proximal end of each component is the most proximal end of each component. The end of each component refers to the portion including the end of each component and its periphery. That is, the distal end of each component refers to the portion including the distal end of each component and its periphery, and the proximal end of each component refers to the portion including the proximal end of each component and its periphery. The longitudinal axis direction may be designated x, the radial direction y, and the circumferential direction z.

[0013] FIG. 1 is a side view showing an embodiment of a catheter. FIG. 2 is a partially enlarged view of the band shown in FIG. 1. FIG. 3 is a partially enlarged view of the catheter shown in FIG. 1 when a coil is used instead of the braided tube. As shown in FIGS. 1 to 3, the catheter 1 includes a tubular member 10, a braided tube 20 or a coil 30, and a resin band 80. Also shown in FIGS. 1 to 3 is a resin layer 40 located radially outward of the braided tube 20 or the coil 30 and radially inward of the resin band 80. The tubular member 10 has a lumen extending in the longitudinal axis direction x. For example, a guidewire may be inserted through the lumen of the tubular member 10. The braided tube 20 or the coil 30 is disposed radially outward of the tubular member 10 in the y direction. The band 80 is disposed radially outward of the braided tube 20 or the coil 30 in the y direction.

[0014] The band-shaped body 80 is made of resin and is arranged in a spiral shape on the outside of the braided tube 20 or the coil 30 in the radial direction y. By arranging the resin band-shaped body 80 in a spiral shape on the outside of the braided tube 20 or the coil 30 in the radial direction y, the rigidity of the catheter 1 in the portion where the band-shaped body 80 is arranged can be continuously increased along the longitudinal axis direction x. As a result, by arranging the resin band-shaped body 80 in a portion of the section where the braided tube 20 or the coil 30 is arranged relative to the tubular member 10 in the longitudinal axis direction x, the rigidity of the portion of the catheter 1 can be increased, and therefore a pushing force from the proximal side can be transmitted to the tip side of the catheter 1. On the other hand, in the longitudinal axis direction x, the rigidity of sections of the tubular member 10 where the braided tube 20 or the coil 30 is not arranged, and sections where the braided tube 20 or the coil 30 is arranged but the resin strip 80 is not arranged, is lower than the rigidity of sections where the braided tube 20 or the coil 30 is arranged and the resin strip 80 is arranged, so the flexibility of the low-rigidity sections is good.

[0015] The type of resin constituting the strip 80 is not particularly limited, and may include, for example, polyamide resin, polyester resin, polyurethane resin, polyolefin resin, vinyl chloride resin, silicone resin, natural rubber, or a combination thereof, and preferably includes polyamide resin, polyurethane resin, or a combination thereof. The resin may include an elastomer having rubber elasticity, for example, polyamide resin may include polyamide elastomer, and polyurethane resin may include polyurethane elastomer.

[0016] The width L1 of the strip 80 in the longitudinal axis direction x of the cylindrical member 10 is, for example, preferably 1 to 10 mm, more preferably 1.5 to 5 mm, and even more preferably 1.5 to 3 mm.

[0017] The thickness of the strip 80 in the radial direction y is, for example, preferably 5 to 100 μm, more preferably 10 to 90 μm, and even more preferably 20 to 80 μm.

[0018] The strip 80 may have a single layer structure, or may have a structure in which multiple layers are stacked in the radial direction y of the strip 80. When the strip 80 has a stacked structure, adjacent layers in the radial direction y of the strip 80 may contain different types of resins or may contain the same type of resin.

[0019] The band-shaped body 80 may be fixed to the braided tube 20 or the coil 30. The fixing method is not particularly limited, and may be fixed via an adhesive or by heat fusion, for example.

[0020] 1 to 3, the band-shaped bodies 80 may have gaps between adjacent band-shaped bodies 80 in a side view of the catheter 1. The presence of gaps improves the stretchability of the catheter 1 in the longitudinal axis direction x.

[0021] The gap distance L2 between adjacent band-shaped bodies 80 in the longitudinal axis direction x of the tubular member 10 is, for example, preferably 0.10 mm to 7 mm, more preferably 0.15 mm to 5 mm, and even more preferably 0.2 mm to 3 mm. When there are multiple gaps, the gap distances L2 between adjacent gaps may be the same or different. When there are multiple gaps and the gap distances L2 between adjacent gaps are different, the gap distance L2 may gradually decrease or gradually increase from the proximal side to the distal side in the longitudinal axis direction x, and is preferably gradually increased. By gradually increasing the gap distance L2 from the proximal side to the distal side in the longitudinal axis direction x, the rigidity of the catheter 1 gradually decreases from the proximal side to the distal side, thereby improving the flexibility on the distal side.

[0022] When the band-shaped bodies 80 have gaps between adjacent band-shaped bodies 80, it is preferable that the width L1 (mm) of the band-shaped body 80 in the longitudinal axis direction x of the tubular member 10 and the distance L2 (mm) of the gap between adjacent band-shaped bodies 80 satisfy the relationship expressed by the following formula (1) when viewed from the side of the catheter 1. Satisfying the relationship of the following formula (1) makes manufacturing easier: L2≦L1 (1)

[0023] It is more preferable that the width L1 (mm) of the band-shaped body 80 in the longitudinal axis direction x of the cylindrical member 10 and the distance L2 (mm) of the gap between adjacent band-shaped bodies 80 satisfy the relationship expressed by the following formula (1a), and it is even more preferable that they satisfy the relationship expressed by the following formula (1b): L2 + 0.1 ≦ L1 (1a) L2 + 0.3 ≦ L1 (1b)

[0024] 1 to 3, the catheter 1 may have a resin layer 40 on the radially outer side of the braided tube 20 or the coil 30 in the radial direction y and on the radially inner side of the band-shaped body 80 in the radial direction y. By having the resin layer 40 in the catheter 1, the braided tube 20 or the coil 30 can be protected.

[0025] The resin layer 40 may contain, for example, a polyamide resin, a polyester resin, a polyurethane resin, a polyolefin resin, a vinyl chloride resin, a silicone resin, a natural rubber, or a combination thereof, and preferably contains a polyamide resin, a polyurethane resin, or a combination thereof. The resin may contain an elastomer having rubber elasticity, for example, a polyamide resin may contain a polyamide elastomer, and a polyurethane resin may contain a polyurethane elastomer.

[0026] The resin layer 40 may have a single-layer structure, or may have a structure in which multiple layers are stacked in the radial direction y of the tubular member 10. When the resin layer 40 has a stacked structure, adjacent layers in the radial direction y of the tubular member 10 may contain different types of resins or may contain the same type of resin.

[0027] When the catheter 1 has a resin layer 40, the Shore D hardness of the band-shaped body 80 is preferably greater than the Shore D hardness of the resin layer 40. This allows the thickness of the band-shaped body 80 to be thinner, thereby allowing the outer diameter of the catheter 1 to be smaller. The Shore D hardness of the band-shaped body 80 is preferably greater than the Shore D hardness of the resin layer 40 by, for example, 5 HS or more, more preferably 10 HS or more, and even more preferably 20 HS or more. The Shore D hardness of the band-shaped body 80 may be, for example, 20 to 87 HS. The Shore D hardness of the resin layer 40 may be, for example, less than 75 HS.

[0028] When the catheter 1 has a resin layer 40, the band-shaped body 80 may be fixed to the resin layer 40. The fixing method is not particularly limited, and for example, the band-shaped body 80 may be fixed via an adhesive or by heat fusion.

[0029] The braided tube 20 preferably has a mesh structure in which the wires 21 are woven so as to cross each other.

[0030] As shown in Figure 2, the wires 21 of the braided tube 20 have an inclined portion that is inclined with respect to the longitudinal axis direction x of the tubular member 10, and preferably satisfy the relationship expressed by the following formula (2) in a side view of the catheter 1. In formula (2), θ1 represents the angle between the longitudinal axis direction x of the tubular member 10 and the inclination direction of the band-shaped body 80 (the inclination angle of the band-shaped body 80), and θ2 represents the angle between the longitudinal axis direction x of the tubular member 10 and the inclination direction of the wires 21 (the inclination angle of the wires 21). The inclination direction of the band-shaped body 80 and the inclination direction of the wires 21 differ with respect to the longitudinal axis direction x of the tubular member 10, thereby increasing the rigidity of the catheter 1. Note that θ1 and θ2 are both acute angles. θ1 ≠ θ2 ... (2)

[0031] The angle θ1 formed between the longitudinal axis direction x of the tubular member 10 and the inclination direction of the band-shaped body 80 is, for example, preferably 25° to 75°, more preferably 30° to 70°, and even more preferably 35° to 65°. The angle θ2 formed between the longitudinal axis direction x of the tubular member 10 and the inclination direction of the wires 21 is, for example, preferably 5° to 90°, more preferably 10° to 80°, and even more preferably 15° to 70°. The absolute value of the difference between θ1 and θ2 is not particularly limited, but may be, for example, more than 0° and not more than 65°, and is preferably 3° to 60°, and more preferably 5° to 50°.

[0032] As shown in Figure 3, the coil 30 has an inclined portion that is inclined with respect to the longitudinal axis direction x of the tubular member 10, and preferably satisfies the relationship expressed by the following formula (3) in a side view of the catheter 1. In formula (3), θ1 represents the angle between the longitudinal axis direction x of the tubular member 10 and the inclination direction of the band-shaped body 80 (the inclination angle of the band-shaped body 80), and θ3 represents the angle between the longitudinal axis direction x of the tubular member 10 and the inclination direction of the coil 30 (the inclination angle of the coil 30). The inclination direction of the band-shaped body 80 and the inclination direction of the coil 30 differ with respect to the longitudinal axis direction x of the tubular member 10, thereby increasing the rigidity of the catheter 1. Note that θ1 and θ3 are both acute angles. θ1 ≠ θ3 ... (3)

[0033] The angle θ1 between the longitudinal axis direction x of the tubular member 10 and the inclination direction of the band-shaped body 80 is, for example, preferably 25° to 75°, more preferably 30° to 70°, and even more preferably 35° to 65°. The angle θ3 between the longitudinal axis direction x of the tubular member 10 and the inclination direction of the coil 30 is, for example, preferably 5° to 90°, more preferably 10° to 80°, and even more preferably 15° to 70°. The absolute value of the difference between θ1 and θ3 is not particularly limited, but may be, for example, more than 0° and not more than 65°, and is preferably 3° to 60°, and more preferably 5° to 50°.

[0034] The coil 30 may be a right-handed or left-handed spiral, and the band-shaped body 80 may be a right-handed or left-handed spiral. That is, in the longitudinal axis direction x of the tubular member 10, the winding direction of the coil 30 from the proximal end to the distal end may be a right-handed (clockwise) spiral or a left-handed (counterclockwise) spiral. In the longitudinal axis direction x of the tubular member 10, the winding direction of the band-shaped body 80 from the proximal end to the distal end may be a right-handed (clockwise) spiral or a left-handed (counterclockwise) spiral. The winding direction of the coil 30 and the winding direction of the band-shaped body 80 may be the same or different, and preferably different. When the winding direction of the coil 30 and the winding direction of the band-shaped body 80 are the same, it is preferable that the inclination angle θ1 of the band-shaped body 80 is smaller than the inclination angle θ3 of the coil 30. This makes it difficult for the coil 30 to collapse even when stress is applied in the longitudinal axis direction x of the tubular member 10, thereby preventing the resin disposed between the coils 30 from being crushed and protruding outside the coil 30. As a result, buckling of the catheter 1 can be prevented. When the winding direction of the coil 30 and the winding direction of the band-shaped body 80 are different, the coil 30 is a right-handed spiral and the band-shaped body 80 is a left-handed spiral, or the coil 30 is a left-handed spiral and the band-shaped body 80 is a right-handed spiral. By reversing the winding directions of the coil 30 and the band-shaped body 80, the coil 30 is difficult to collapse even when stress is applied in the longitudinal axis direction x of the tubular member 10, thereby preventing the resin disposed between the coils 30 from being crushed and protruding outside the coil 30. As a result, buckling of the catheter 1 can be prevented.

[0035] The band-shaped body 80 may be disposed at the proximal end of the braided tube 20 or the coil 30 in the longitudinal axis direction x of the tubular member 10. This increases the rigidity of the proximal end of the section where the braided tube 20 or the coil 30 is disposed in the tubular member 10 in the longitudinal axis direction x, thereby enabling the pushing force from the proximal side to be transmitted to the distal side.

[0036] The wire 21 of the braided tube 20 may be a single wire or a twisted wire. The wire 21 constituting the braided tube 20 may be one wire or multiple wires.

[0037] The braid density of the braided tube 20 may be uniform or non-uniform along the longitudinal axis x. If the braid density is non-uniform, the braid density may be higher on the proximal side and lower on the distal side of the braided tube 20. Increasing the braid density on the proximal side increases the rigidity of the catheter 1, allowing the pushing force from the proximal side to be transmitted to the distal side. Reducing the braid density on the distal side increases the flexibility of the catheter 1.

[0038] The wires 21 of the braided tube 20 preferably include metal wires, fibers, or a combination thereof, more preferably metal wires. The metal wires preferably include, for example, stainless steel, titanium, nickel-titanium alloys, nickel-chromium alloys, cobalt-chromium alloys, tungsten alloys, or a combination thereof, more preferably stainless steel. The fibers preferably include, for example, polyarylate fibers, aramid fibers, ultra-high molecular weight polyethylene fibers, polyparaphenylene benzobisoxazole fibers (PBO fibers), carbon fibers, or a combination thereof. The fibers may be monofilaments or multifilaments.

[0039] The wires 21 of the braided tube 20 may contain a radiopaque material, which allows the position of the braided tube 20 to be confirmed under X-ray fluoroscopy. The radiopaque material preferably contains, for example, lead, barium, iodine, tungsten, gold, platinum, iridium, platinum-iridium alloy, stainless steel, titanium, cobalt-chromium alloy, palladium, tantalum, or a combination thereof.

[0040] The shape of the cross section perpendicular to the longitudinal axis direction x of the wires 21 of the braided tube 20 is not particularly limited, and may be, for example, a circle, an ellipse, an oval, an egg, a D-shape, a triangle, a rectangle, a polygon, or a combination thereof. The braided tube 20 may also be made of a round wire or a flat wire. A flat wire is a round wire with both sides scraped off.

[0041] The wire diameter of the wires 21 of the braided tube 20 is, for example, preferably 5 to 110 μm, more preferably 10 to 100 μm, and even more preferably 15 to 90 μm. The wire diameter of the wires 21 refers to the maximum length (maximum width) of the wires 21 in a cross section perpendicular to the longitudinal axis direction x of the wires 21 of the braided tube 20.

[0042] The width L1 of the band-shaped body 80 in the longitudinal axis direction x of the tubular member 10 is preferably at least three times, more preferably at least four times, and even more preferably at least five times the wire diameter of the wires 21 of the braided tube 20 .

[0043] The coil 30 may be a solid wire or a stranded wire.

[0044] The winding pitch of the coil 30 may be uniform or non-uniform in the longitudinal axis direction x. When the winding pitch of the coil 30 is non-uniform, the winding pitch of the coil 30 may be large on the proximal side of the coil 30 and small on the distal side. A large winding pitch on the proximal side increases the rigidity of the catheter 1, allowing the pushing force from the proximal side to be transmitted to the tip side. A small winding pitch on the distal side increases the flexibility of the catheter 1.

[0045] The coil 30 preferably includes a metal wire, a fiber, or a combination thereof, and more preferably includes a metal wire. The metal wire preferably includes, for example, stainless steel, titanium, a nickel-titanium alloy, a nickel-chromium alloy, a cobalt-chromium alloy, a tungsten alloy, or a combination thereof, and more preferably includes stainless steel. The fiber preferably includes, for example, a polyarylate fiber, an aramid fiber, an ultra-high molecular weight polyethylene fiber, a polyparaphenylene benzobis oxazole fiber (PBO fiber), a carbon fiber, or a combination thereof. The fiber may be a monofilament or a multifilament.

[0046] The coil 30 may include a radiopaque material, which allows the position of the coil 30 to be confirmed under X-ray fluoroscopy. The radiopaque material preferably includes, for example, lead, barium, iodine, tungsten, gold, platinum, iridium, platinum-iridium alloy, stainless steel, titanium, cobalt-chromium alloy, palladium, tantalum, or a combination thereof.

[0047] The shape of the cross section of the coil 30 perpendicular to the longitudinal axis direction x is not particularly limited, and examples thereof include a circle, an ellipse, an oval, an egg, a D-shape, a triangle, a rectangle, a polygon, or a combination thereof. The coil may also be made of a round wire or a flat wire. A flat wire is a round wire with both sides scraped off.

[0048] The wire diameter of the coil 30 is, for example, preferably 3 to 300 μm, more preferably 5 to 250 μm, and even more preferably 10 to 200 μm. The wire diameter of the coil 30 refers to the maximum length (maximum width) of the coil 30 in a cross section perpendicular to the longitudinal axis direction x of the coil 30.

[0049] The width L1 of the band-shaped body 80 in the longitudinal axis direction x of the tubular member 10 is preferably 2.0 times or more, more preferably 2.5 times or more, and even more preferably 3.0 times or more, relative to the wire diameter of the coil 30.

[0050] The braided tube 20 or the coil 30 may be disposed within the resin layer 40. The catheter 1 may have an intermediate layer disposed on the outside of the tubular member 10 in the radial direction y of the tubular member 10, and the resin layer 40 disposed outside the intermediate layer. That is, the intermediate layer may be disposed between the tubular member 10 and the resin layer 40. By forming a laminated structure of the intermediate layer and the resin layer 40, it is possible to vary the hardness of the tubular member 10 in the radial direction y of the tubular member 10. When the intermediate layer is disposed on the outside of the tubular member 10 in the radial direction y of the tubular member 10, and the resin layer 40 is disposed outside the intermediate layer, the braided tube 20 or the coil 30 may be disposed within the intermediate layer. The intermediate layer and the resin layer 40 may be fixed together. The fixing method is not particularly limited, and for example, they may be fixed together via an adhesive or by heat fusion.

[0051] The intermediate layer may be made of a resin. The resin may include, for example, a polyamide resin, a polyester resin, a polyurethane resin, a polyolefin resin, a vinyl chloride resin, a silicone resin, a natural rubber, or a combination thereof, and preferably includes a polyamide resin, a polyurethane resin, or a combination thereof. The resin may include an elastomer having rubber elasticity. For example, the polyamide resin may include a polyamide elastomer, and the polyurethane resin may include a polyurethane elastomer.

[0052] The intermediate layer may have a single-layer structure, or may have a structure in which multiple layers are stacked in the radial direction y of the tubular member 10. When the intermediate layer has a stacked structure, adjacent layers in the radial direction y of the tubular member 10 may contain different types of resins or may contain the same type of resin.

[0053] The cylindrical member 10 may be any resin tube, preferably containing a fluororesin, and more preferably made of a fluororesin. Fluororesin has excellent chemical resistance, non-stick properties, and low friction. The fluororesin preferably contains, for example, polytetrafluoroethylene, ethylene tetrafluoroethylene, fluorinated ethylene propylene, or a combination thereof.

[0054] The catheter 1 may have a radiopaque ring. The proximal end 20a or the distal end 20b of the braided tube 20 may be disposed inside the radiopaque ring in the radial direction y. This allows the position of the proximal end 20a or the distal end 20b of the braided tube 20 to be confirmed under X-ray fluoroscopy.

[0055] The catheter 1 is not particularly limited as long as it is inserted into a blood vessel or a body cavity, and may be used in, for example, a blood vessel, a ureter, a bile duct, a fallopian tube, a hepatic duct, or the like.

[0056] Fig. 4 is a side view showing another embodiment of the catheter. Fig. 4 shows a configuration example using a braided tube 20, but the embodiment of the catheter 1 (1A) is not limited to this, and a coil 30 may be used instead of the braided tube 20. Fig. 5 is a side view showing the catheter shown in Fig. 4 inserted into a second catheter, with a portion of the catheter protruding from the opening at the distal end of the second catheter. The resin band 80 is not shown in Figs. 4 and 5. In Figs. 4 and 5, the right side of the figure is the proximal side, and the left side of the figure is the distal side.

[0057] The catheter 1 may further include a linear member 60 fixed to the tubular member 10 and extending proximally from the tubular member 10. This allows the operator to push the tubular member 10 distally or pull it back proximally via the linear member 60.

[0058] The distal end 60b of the linear member 60 may be located proximal to the proximal end 20a of the braided tube 20, but is preferably located distal to the proximal end 20a of the braided tube 20. This makes it easier for the tubular member 10 to bend smoothly from the portion where the braided tube 20 is disposed to the portion proximal to the proximal end 20a of the braided tube 20 when the tubular member 10 is inserted into a curved portion of a blood vessel or body cavity.

[0059] The linear member 60 may have a lumen extending in the longitudinal axis direction x, but is preferably solid and does not have a lumen, which allows the thickness of the linear member 60 to be reduced.

[0060] The linear member 60 may be made of any material, including, but not limited to, a metal, as long as it can push the tubular member 10 distally and pull it back proximally. The metal preferably includes, for example, stainless steel, titanium, a nickel-titanium alloy, a cobalt-chromium alloy, a tungsten alloy, or a combination thereof, and more preferably includes stainless steel.

[0061] The shape of the linear member 60 in a cross section perpendicular to the longitudinal axis direction x is preferably, for example, a square, rectangle, trapezoid, circle, ellipse, egg, oval, or D-shape, and more preferably a rectangle. The shape of the linear member 60 in a cross section perpendicular to the longitudinal axis direction x may be the same regardless of the position in the longitudinal axis direction x, or may be different depending on the position in the longitudinal axis direction x.

[0062] The wire diameter of the linear member 60 is, for example, preferably 100 to 650 μm, more preferably 150 to 600 μm, and even more preferably 200 to 550 μm. The wire diameter of the linear member 60 refers to the maximum length (maximum width) of the linear member 60 in a cross section perpendicular to the longitudinal axis direction x of the linear member 60. The wire diameter of the linear member 60 may be the same regardless of the position in the longitudinal axis direction x, or may be different depending on the position in the longitudinal axis direction x, and may have, for example, a portion that tapers from the proximal side to the distal side.

[0063] When the catheter 1 further has a linear member 60, the catheter 1 may be an extension catheter 1A as shown in Fig. 4. As shown in Fig. 5, the extension catheter 1A has a lumen extending in the longitudinal axis direction x of the tubular member 10, and is a catheter to be inserted into a second catheter 2 having an opening 2bP at its distal end 2b, and the distal end 10b of the tubular member 10 can protrude from the opening 2bP at the distal end 2b of the second catheter 2.

[0064] For example, after inserting the distal end of the second catheter 2 into the entrance of a coronary artery, the extension catheter 1A is inserted into the second catheter 2 through an opening 2aP at the proximal end 2a of the second catheter 2, and then inserted into the coronary artery with a portion of the extension catheter 1A protruding from an opening 2bP at the distal end 2b of the second catheter 2, thereby enabling delivery of, for example, an intravascular treatment device to an affected area in the coronary artery via the second catheter 2 and the extension catheter 1A. Examples of intravascular treatment devices include a balloon and a stent.

[0065] The second catheter 2 is preferably a so-called guiding catheter. A guiding catheter has a lumen into which a treatment catheter such as a balloon catheter or a stent delivery catheter is inserted. The treatment catheter is preferably inserted into a coronary artery, but may also be inserted into other arteries such as a cerebral artery, or into internal ducts such as veins, pancreatic ducts, bile ducts, ureters, or bronchi.

[0066] The catheter 1 may further have a handle member 70 fixed to the proximal end of the tubular member 10. When the catheter 1 is an extension catheter 1A having a linear member 60, the extension catheter 1A may further have a handle member 70 fixed to the proximal end of the linear member 60, as shown in Figure 4. This allows the operator to grasp the handle member 70 and move the tubular member 10 or the linear member 60 distally or proximally.

[0067] The handle member 70 preferably contains a resin, such as a polyolefin resin, which preferably contains, for example, polyethylene, polypropylene, or a combination thereof.

[0068] Next, a method for manufacturing the catheter will be described. The catheter 1 can be manufactured by a method including a step of arranging the braided tube 20 or the coil 30 radially outside in the y direction of a tubular member 10 having a lumen extending in the longitudinal axis direction x (hereinafter, sometimes referred to as step A), and a step of helically arranging the resin band 80 radially outside in the y direction of the braided tube 20 or the coil 30 (hereinafter, sometimes referred to as step B). In step A, the tubular member 10 and the braided tube 20 or the coil 30 may be fixed to each other via an adhesive or by heat fusion. In step B, the braided tube 20 or the coil 30 and the resin band 80 may be fixed to each other via an adhesive or by heat fusion.

[0069] When manufacturing a catheter 1 having a resin layer 40 radially outward of the braided tube 20 or coil 30 and radially inward of the band-shaped body 80, a step (hereinafter sometimes referred to as step C) of arranging the resin layer 40 radially outward of the braided tube 20 or coil 30 may be included between the step (step A) of arranging the braided tube 20 or coil 30 and the step (step B) of spirally arranging the resin band-shaped body 80. This allows the braided tube 20 or coil 30 to be protected. The resin layer 40 may be any of those described above.

[0070] When manufacturing a catheter 1 having an intermediate layer radially outward from the braided tube 20 or the coil 30, a resin layer 40 radially outward from the intermediate layer, and a band-shaped body 80 outside the resin layer 40, a step (hereinafter sometimes referred to as step D) of arranging the intermediate layer radially outward from the braided tube 20 or the coil 30 may be included between steps A and C.

[0071] In the step (step B) of spirally arranging the resin strip 80, the resin strip 80 may be spirally arranged while applying a force in a direction that moves one end of the strip 80 away from the other end of the strip 80. This allows a gap to be formed between adjacent strips 80.

[0072] This application claims the benefit of priority based on Japanese Patent Application No. 2024-52171, filed on March 27, 2024. The entire contents of the specification of Japanese Patent Application No. 2024-52171 are incorporated herein by reference.

[0073] REFERENCE SIGNS LIST 1 Catheter 1A Extension catheter 2 Second catheter 2a Proximal end of second catheter 2b Distal end of second catheter 2aP Opening at proximal end of second catheter 2bP Opening at distal end of second catheter 10 Cylindrical member 10a Proximal end of tubular member 10b Distal end of tubular member 20 Braided tube 20a Proximal end of braided tube 20b Distal end of braided tube 21 Wire of braided tube 30 Coil 30a Proximal end of coil 30b Distal end of coil 40 Resin layer 50 Intermediate layer 60 Linear member 70 Handle member 80 Band-shaped body 80a Gap

Claims

1. A catheter having a tubular member with an inner lumen extending in the longitudinal direction, a braided tube or a coil located radially outside the tubular member, and a resin band-shaped body arranged in a spiral shape radially outside the braided tube or the coil in a partial section in the longitudinal direction.

2. A catheter as described in claim 1, further comprising a resin layer located radially outward of said braided tube or said coil and radially inward of said band-shaped body, wherein the Shore D hardness of said band-shaped body is greater than the Shore D hardness of said resin layer.

3. The catheter according to claim 1, wherein, in a side view of the catheter, the bands have gaps between adjacent bands.

4. The catheter according to claim 3, wherein, in a side view of the catheter, when the width of the band-shaped body in the longitudinal axis direction of the tubular member is L1 and the distance between the gaps between adjacent band-shaped bodies is L2, the width L1 and the distance L2 between the gaps satisfy the relationship expressed by the following formula (1): L2≦L1 (1) 5. The catheter according to claim 1, wherein the braided tube has wires, the wires having inclined portions inclined with respect to the longitudinal axis direction of the tubular member, and the catheter satisfies the relationship expressed by the following formula (2) in a side view: θ1 ≠ θ2 ... (2) [In formula (2), θ1 represents the angle between the longitudinal axis direction of the tubular member and the inclination direction of the band-shaped body. θ2 represents the angle between the longitudinal axis direction of the tubular member and the inclination direction of the wires.] 6. The catheter according to claim 5, wherein the absolute value of the difference between θ1 and θ2 is greater than 0° and less than or equal to 65°.

7. The catheter according to claim 1, wherein the coil has an inclined portion inclined with respect to the longitudinal axis direction of the tubular member, and the relationship expressed by the following formula (3) is satisfied in a side view of the catheter: θ1 ≠ θ3 ... (3) [In formula (3), θ1 represents the angle between the longitudinal axis direction of the tubular member and the inclination direction of the band-shaped body. θ3 represents the angle between the longitudinal axis direction of the tubular member and the inclination direction of the coil.] 8. The catheter according to claim 7, wherein the absolute value of the difference between θ1 and θ3 is greater than 0° and equal to or less than 65°.

9. The catheter according to claim 1, wherein the band is disposed at a proximal end of the braided tube or the coil in the longitudinal direction of the tubular member.

10. The catheter according to claim 1, further comprising a linear member fixed to the tubular member and extending proximally from the tubular member, and an extension catheter having an inner cavity extending in the longitudinal axis direction of the tubular member, inserted into a second catheter having an opening at its distal end, and capable of protruding from the opening of the second catheter.

11. A method for manufacturing a catheter, comprising the steps of: arranging a braided tube or a coil radially outside a tubular member having an inner lumen extending in the longitudinal direction; and arranging a resin band in a spiral shape radially outside the braided tube or the coil.

12. A manufacturing method as described in claim 11, further comprising, between the step of arranging the braided tube or coil and the step of spirally arranging the resin strip, a step of arranging a resin layer radially outward of the braided tube or coil.

13. A manufacturing method according to claim 11 or 12, wherein in the step of arranging the strip in a spiral shape, a force is applied in a direction that moves one end of the strip away from the other end.

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