Catheter

Abstract

To provide a catheter hardly generating kink even when being used in a bent state.SOLUTION: A catheter includes: a cylindrical member having a lumen extending in a longitudinal axis direction; a braided tube positioned outside the radial direction of the cylindrical member and having an element wire; and an outer layer positioned outside the radial direction of the braided tube. The catheter is configured such that a coil is arranged between the braided tube and the outer layer, and when a winding pitch of the element wire is P1, and a winding pitch of the coil is P2 in a lateral side view of the catheter, the winding pitch P1 of the element wire and the winding pitch P2 of the coil satisfy a relationship represented by the following formula (1): P1≥P2 ...(1).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a catheter. [Background technology]

[0002] Various catheters are used in medical settings. By inserting a catheter into a blood vessel or a body cavity and reaching the distal end of the catheter to a target location, treatments and diagnoses, such as administering or injecting a drug or contrast agent, can be performed. To insert a catheter into a blood vessel or a body cavity, the catheter must be highly adaptable to the shape of the blood vessel or body cavity, and the distal end of the catheter must be particularly flexible. Meanwhile, to navigate the catheter within a blood vessel or a body cavity, the catheter must be able to transmit a pushing force (pushability) from the proximal side to the distal end. Thus, catheters must be flexible and rigid enough to transmit a pushing force from the proximal side to the distal end. Patent Document 1, for example, discloses such a catheter, having a first coil portion fixed to the distal end of a braided portion in an extended state and a second coil portion fixed to the proximal end of the braided portion in a contracted state. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6513997 Summary of the Invention [Problem to be solved by the invention]

[0004] In addition to flexibility and rigidity that allows the pushing force from the proximal side to be transmitted to the distal side, catheters are also required to be able to avoid kinking even when used in a bent state.

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a catheter that is less likely to kink even when used in a bent state. [Means for solving the problem]

[0006] The present invention is as follows. [1] A catheter having a tubular member having an inner cavity extending in the longitudinal axis direction, a braided tube located radially outside the tubular member and having wires, and an outer layer located radially outside the braided tube, wherein a coil is disposed between the braided tube and the outer layer, and when, in a side view of the catheter, the winding pitch of the wires is P1 and the winding pitch of the coil is P2, the winding pitch P1 of the wires and the winding pitch P2 of the coil satisfy the relationship expressed by the following formula (1). P1 ≥ P2 (1) [2] The catheter described in [1], wherein the coil has a sparse portion with a winding pitch of P2 and a dense portion with a winding pitch of P3 smaller than P2, and the dense portion of the coil is positioned distal to the sparse portion of the coil in the longitudinal axis direction of the tubular member. [3] A catheter according to [2], wherein the dense portion of the coil is arranged radially outside the distal end of the braided tube. [4] The catheter according to any one of [1] to [3], wherein the wire diameter of the coil is 0.5 to 5 times the wire diameter of the wire of the braided tube. [5] The catheter according to any one of [1] to [4], wherein the coil contains a radiopaque material. [6] The catheter according to [5], wherein the radiopaque material has a modulus of elasticity of 190 GPa or less. [7] The catheter according to any one of [1] to [6], further comprising a linear member fixed to the tubular member and extending proximally from the tubular member. [8] The catheter described in [7] is 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. [Effects of the Invention]

[0007] The catheter according to the present invention includes a braided tube having wires and a coil, and the winding pitch P1 of the wires and the winding pitch P2 of the coil are appropriately controlled. As a result, a catheter that is less likely to kink even when used in a bent state can be provided. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a side view of an embodiment of a catheter. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II of FIG. [Figure 3] FIG. 3 is a side view of the braided tube of FIG. [Figure 4] FIG. 4 is a side view of the coil of FIG. [Figure 5] FIG. 5 is a side view showing another embodiment of the catheter. [Figure 6] FIG. 6 is a side view of the coil of FIG. [Figure 7] FIG. 7 is a cross-sectional view showing another example of the cross-sectional view taken along line II-II of FIG. [Figure 8] FIG. 8 is a side view showing another embodiment of the catheter. [Figure 9] FIG. 9 is a side view showing the catheter shown in FIG. 8 inserted into a second catheter with a portion of the catheter protruding from the opening at the distal end of the second catheter. DETAILED DESCRIPTION OF THE INVENTION

[0009] An embodiment of a catheter according to the present invention is a catheter having a tubular member with an inner lumen extending in the longitudinal axis direction, a braided tube positioned radially outside the tubular member and having wires, and an outer layer positioned radially outside the braided tube, wherein a coil is disposed between the braided tube and the outer layer, and when, in a side view of the catheter, the winding pitch of the wires is P1 and the winding pitch of the coil is P2, the winding pitch P1 of the wires and the winding pitch P2 of the coil satisfy the relationship expressed by the following formula (1). P1 ≥ P2 (1)

[0010] 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. In addition, hatching and component symbols may be omitted in the drawings for convenience. In such cases, reference should be made to the specification and other drawings. Furthermore, 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.

[0011] In this specification, the proximal side refers to the direction toward the user's hand 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.

[0012] Fig. 1 is a side view showing an embodiment of a catheter. Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1. Fig. 3 is a side view of the braided tube in Fig. 1. Fig. 4 is a side view of the coil in Fig. 1. As shown in Fig. 1, the catheter 1 includes a tubular member 10, a braided tube 20, a coil 30, and an outer layer 40. In Fig. 1, the tubular member 10 is indicated by a dotted line.

[0013] The tubular member 10 has an inner cavity extending in the longitudinal direction. As shown in FIG. 2, a braided tube 20 is disposed on the radially outer side of the tubular member 10. By disposing the braided tube 20, the tubular member 10 can be reinforced, and even if a guide wire, for example, is inserted into the inner cavity of the tubular member 10, the guide wire is less likely to penetrate the tubular member 10. Furthermore, by disposing the braided tube 20, the rigidity of the catheter 1 is increased, so that a pushing force from the proximal side can be transmitted to the distal side. As a result, the operability of the catheter 1 is improved. As shown in FIG. 3, the braided tube 20 has wires 21. As shown in FIG. 2, an outer layer 40 is disposed on the radially outer side of the braided tube 20. As shown in FIG. 2, a coil 30 is disposed between the braided tube 20 and the outer layer 40.

[0014] When viewed from the side of the catheter 1, the winding pitch of the wire 21 is P1 and the winding pitch of the coil 30 is P2, and the winding pitch P1 of the wire 21 and the winding pitch P2 of the coil 30 satisfy the relationship expressed by the following formula (1). P1 ≥ P2 (1)

[0015] When the winding pitch P1 of the wire 21 and the winding pitch P2 of the coil 30 satisfy the relationship of the above formula (1), the coil 30 becomes a reinforcing layer of the braided tube 20, making it less likely for kinking to occur even when the catheter 1 is used in a bent state.

[0016] The winding pitch P1 of the wire 21 refers to the length in the longitudinal direction of the tubular member 10 when the wire 21 has made one circumferential turn around the outer surface of the tubular member 10, as shown in Fig. 3. The winding pitch P2 of the coil 30 refers to the length in the longitudinal direction of the tubular member 10 when the coil 30 has made one circumferential turn around the outer surface of the tubular member 10, as shown in Fig. 4. The winding pitch P1 of the wire 21 and the winding pitch P2 of the coil 30 are measured in millimeters.

[0017] The winding pitch P1 of the wire 21 may be 0.1 mm or more larger than the winding pitch P2 of the coil 30 and satisfy the relationship of the following formula (1a), or the winding pitch P1 of the wire 21 may be 0.2 mm or more larger than the winding pitch P2 of the coil 30 and satisfy the relationship of the following formula (1b). P1 ≥ P2 + 0.1 (1a) P1 ≥ P2 + 0.2 (1b)

[0018] Fig. 5 is a side view showing another embodiment of the catheter. Fig. 6 is a side view of the coil of Fig. 5. As shown in Fig. 5, the coil 30 may have a sparse portion where the winding pitch is P2 and a dense portion where the winding pitch is P3 which is smaller than P2. In this case, in a side view of the catheter 1, the winding pitch P2 and the winding pitch P3 of the wire 21 may satisfy the relationship expressed by the following formula (2). The winding pitch P2 of the wire 21 may be 0.1 mm or more larger than the winding pitch P3 and satisfy the relationship expressed by the following formula (2a), or the winding pitch P2 of the wire 21 may be 0.2 mm or more larger than the winding pitch P3 of the coil 30 and satisfy the relationship expressed by the following formula (2b). P2>P3 (2) P2>P3+0.1 (2a) P2>P3+0.2 (2b)

[0019] The winding pitch P3 of the wire 21 is preferably as small as possible, and the closer the wires 21 are to each other, the more X-rays are hindered from passing through, improving visibility. The winding pitch P3 of the wire 21 is preferably 0.2 mm or less, and more preferably 0.1 mm or less, for example.

[0020] When the coil 30 of the catheter 1 has sparse and dense portions, the dense portions of the coil 30 may be disposed distal to the sparse portions of the coil 30 in the longitudinal axis direction of the tubular member 10. This reduces the rigidity of the distal side of the tubular member, improving flexibility and making it easier to insert the catheter 1 into a blood vessel or a body cavity. Furthermore, by reducing the winding pitch of the coil 30 and making it denser, radiopacity is improved, resulting in good visibility.

[0021] When the coil 30 has sparse portions and dense portions, the sparse portions and dense portions may be continuous or discontinuous. That is, one coil 30 may have both sparse portions and dense portions, or the catheter 1 may have multiple coils 30, with a coil 30 having a winding pitch of P2 and a coil 30 having a winding pitch of P3 arranged side by side in the longitudinal axis direction of the tubular member 10.

[0022] When the coil 30 has sparse portions and dense portions, it is preferable that one coil 30 has both sparse portions and dense portions, which makes it less likely that kinks will occur at the boundary between the dense portions and sparse portions.

[0023] When the coil 30 has a sparse portion and a dense portion, the dense portion of the coil 30 may be disposed radially outward at the distal end of the braided tube 20, as shown in Fig. 5. This prevents the wires 21 of the braided tube 20 from opening outward in the radial direction of the tubular member 10.

[0024] The position of the distal end 30b of the coil 30 may be the same as the position of the distal end 10b of the tubular member 10 in the longitudinal axis direction of the tubular member 10, or may be closer to the proximal side than the position of the distal end 10b of the tubular member 10. When the position of the distal end 30b of the coil 30 is closer to the proximal side than the position of the distal end 10b of the tubular member 10, the distal end 30b of the coil 30 is preferably disposed in a region within 5 mm from the distal end 10b of the tubular member 10. This can increase the rigidity of the distal end portion of the tubular member 10.

[0025] The position of the distal end 20b of the braided tube 20 may be the same as the position of the distal end 10b of the tubular member 10 in the longitudinal axis direction of the tubular member 10, or may be more proximal than the position of the distal end 10b of the tubular member 10. When the position of the distal end 20b of the braided tube 20 is more proximal than the position of the distal end 10b of the tubular member 10, the distal end 20b of the braided tube 20 is preferably disposed in a region within 5 mm from the distal end 10b of the tubular member 10. This allows the rigidity of the distal end of the tubular member 10 to be increased.

[0026] The position of the distal end 30b of the coil 30 may be closer to the proximal side than the distal end 20b of the braided tube 20 in the longitudinal axis direction of the tubular member 10, but is preferably the same as the distal end 20b of the braided tube 20 or more distal than the distal end 20b of the braided tube 20, as shown in Fig. 5. By having the distal end 30b of the coil 30 be the same as the distal end 20b of the braided tube 20 or more distal than the distal end 20b of the braided tube 20, the wires 21 at the distal end of the braided tube 20 can be prevented from opening outward in the radial direction of the tubular member 10.

[0027] The coil 30 is arranged between the braided tube 20 and the outer layer 40, and may be arranged outside the braided tube 20 and inside the outer layer 40 in the radial direction of the tubular member 10, or may be arranged within the outer layer 40 as shown in Figure 2.

[0028] The braided tube 20 is arranged radially outside the tubular member 10, and the outer layer 40 may be arranged radially outside the braided tube 20 of the tubular member 10, or may be arranged within the outer layer 40 as shown in Figure 2.

[0029] Fig. 7 is a cross-sectional view showing another example of the cross-sectional view taken along line II-II in Fig. 1. In Fig. 7, an intermediate layer 50 is disposed on the outside of the tubular member 10 in the radial direction of the tubular member 10, and an outer layer 40 is disposed on the outside of the intermediate layer 50. The braided tube 20 is disposed within the intermediate layer 50, and the coil 30 is disposed within the outer layer 40. By forming a layered structure of the intermediate layer 50 and the outer layer 40, it is possible to vary the hardness of the tubular member 10 in the radial direction.

[0030] The outer layer 40 and the intermediate layer 50 preferably contain, for example, polyamide resin, polyester resin, polyurethane resin, polyolefin resin, vinyl chloride resin, silicone resin, natural rubber, or a combination thereof. The outer layer 40 and the intermediate layer 50 more preferably contain polyamide resin, polyurethane resin, or a combination thereof. These resins may contain elastomers with rubber elasticity. For example, polyamide resins may contain polyamide elastomers, and polyurethane resins may contain polyurethane elastomers. The outer layer 40 and the intermediate layer 50 may contain different types of resins or the same type of resin.

[0031] The outer layer 40 may be a single layer, or may have a structure in which multiple layers are laminated in the radial direction of the tubular member 10. When the outer layer 40 has a laminated structure, the layers adjacent in the radial direction of the tubular member 10 may contain different types of resins, or may contain the same type of resin. The intermediate layer 50 may be a single layer, or may have a structure in which multiple layers are laminated in the radial direction of the tubular member 10. When the intermediate layer 50 has a laminated structure, the layers adjacent in the radial direction of the tubular member 10 may contain different types of resins, or may contain the same type of resin.

[0032] The outer layer 40 may have a hydrophilic polymer on the outer surface in the radial direction of the tubular member 10. This makes it easier to insert the catheter 1 into a blood vessel, a body cavity, or a second catheter (for example, a guiding catheter) described below.

[0033] The hydrophilic polymer preferably includes, for example, poly(2-hydroxyethyl methacrylate), polyacrylamide, polyvinylpyrrolidone, maleic anhydride copolymer, or a combination thereof. The maleic anhydride copolymer is preferably a methyl vinyl ether maleic anhydride copolymer.

[0034] The coil 30 may be a solid wire or a stranded wire.

[0035] The coil 30 preferably comprises a metal wire, a fiber, or a combination thereof, and more preferably comprises a metal wire. The metal wire preferably comprises, 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 comprises stainless steel. The fiber preferably comprises, for example, polyarylate fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, polyparaphenylene benzobisoxazole fiber (PBO fiber), carbon fiber, or a combination thereof. The fiber may be a monofilament or a multifilament.

[0036] 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.

[0037] The radiopaque material may have a modulus of elasticity of 190 GPa or less, which can improve flexibility. Examples of radiopaque materials having a modulus of elasticity of 190 GPa or less include lead, gold, platinum, platinum-iridium alloy, titanium, palladium, and tantalum.

[0038] The shape of the cross section perpendicular to the longitudinal axis of the coil 30 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 coil 30 may also be made of a round wire or a flat wire. A flat wire is a round wire with both sides scraped off.

[0039] The wire diameter of the coil 30 is, for example, preferably 3 to 300 μm, more preferably 5 to 200 μm, and even more preferably 10 to 100 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 of the coil 30.

[0040] The braided tube 20 preferably has a mesh structure in which the wires 21 are woven so as to cross each other. The wires 21 may be solid wires or twisted wires. The braided tube 20 may include one or more wires 21.

[0041] 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. 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.

[0042] 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.

[0043] The shape of the cross section perpendicular to the longitudinal axis 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 wire material with both sides scraped off from a round wire.

[0044] 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 of the braided tube 20 perpendicular to the longitudinal axis direction of the wires 21.

[0045] The combination of the shape of the coil 30 in a cross section perpendicular to the longitudinal axis direction and the shape of the wire 21 of the braided tube 20 in a cross section perpendicular to the longitudinal axis direction is not particularly limited, but a combination of a coil 30 including a flat wire or a round wire and a braided tube 20 including a flat wire or a round wire is preferred.

[0046] The wire diameter of the coil 30 may be 0.5 to 5 times, 1 to 4 times, or 1.5 to 3 times the wire diameter of the wires 21 of the braided tube 20.

[0047] 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-stickiness, and low friction. The fluororesin preferably contains, for example, polytetrafluoroethylene, ethylene tetrafluoroethylene, fluorinated ethylene propylene, or a combination thereof.

[0048] The tubular member 10 may have a radiopaque ring. The proximal end or distal end 20b of the braided tube 20 may be disposed radially inside the radiopaque ring. This allows the position of the proximal end or distal end 20b of the braided tube 20 to be confirmed under X-ray fluoroscopy.

[0049] The radiopaque ring may be disposed between the braided tube 20 and the outer layer 40 in the radial direction of the tubular member 10. This prevents the end of the braided tube 20 from opening, thereby preventing the braided tube 20 from being exposed from the outer surface of the outer layer 40. The radiopaque ring is a ring containing a radiopaque material, and may be a ring made of a radiopaque material. The radiopaque materials exemplified above can be used.

[0050] The use of the catheter is not particularly limited as long as it can be inserted into a blood vessel or a body cavity, and may be, for example, a blood vessel, a ureter, a bile duct, a fallopian tube, or a hepatic duct.

[0051] Figure 8 is a side view showing another embodiment of the catheter. Note that the coil 30 is not shown in Figure 8. Figure 9 is a side view showing the catheter shown in Figure 8 inserted into a second catheter, with a portion of the catheter protruding from the opening at the distal end of the second catheter. Note that the coil 30 is not shown in Figure 9. The longitudinal direction may be represented as x, the radial direction as y, and the circumferential direction as z.

[0052] 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.

[0053] 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 distally. This makes it easier for the braided tube 20 and then the portion proximal to the braided tube 20 to bend smoothly when the tubular member 10 is inserted into a curved portion of a blood vessel or body cavity.

[0054] 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.

[0055] The linear member 60 may be made of any material, including, but not limited to, metal, as long as it can push the tubular member 10 distally and pull it back proximally. Metals preferably include, for example, stainless steel, titanium, nickel-titanium alloys, cobalt-chromium alloys, tungsten alloys, or combinations thereof, and more preferably include stainless steel.

[0056] 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, D-shape, ellipse, egg shape, or oval 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.

[0057] 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 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.

[0058] When the catheter 1 further has a linear member 60, the catheter 1 may be an extension catheter 1A, as shown in Fig. 8. As shown in Fig. 9, 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 is a catheter that can protrude from the opening 2bP at the distal end 2b of the second catheter 2.

[0059] For example, after inserting the distal end of the second catheter 2 into the entrance of the coronary artery, the extension catheter 1A is inserted into the second catheter 2 from an opening 2aP on the proximal side 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.

[0060] 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 one that is inserted into a coronary artery, but may also be one that is inserted into other arteries such as a cerebral artery, or into internal ducts such as veins, pancreatic ducts, bile ducts, ureters, and bronchi.

[0061] 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 Fig. 9. The operator can grasp the handle member 70 to move the tubular member 10 or the linear member 60 distally or proximally.

[0062] The handle member 70 preferably contains a resin, such as a polyolefin resin, which preferably contains, for example, polyethylene, polypropylene, or a combination thereof. [Example]

[0063] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples, and it is of course possible to carry out the invention by making modifications within the scope that is compatible with the above-mentioned and below-mentioned aims, and all such modifications are included in the technical scope of the present invention.

[0064] [Raw catheter] A 25 μm-thick PTFE tube was prepared as a cylindrical member having a lumen extending in the longitudinal axis direction x. A braided tube having wires was coated on the outside of the PTFE tube in the radial direction y, and an intermediate layer was then coated on the surface to produce a raw catheter. The wires constituting the braided tube were round wires with a wire diameter of 0.025 mm. Two of these round wires were used to form a 16-strand braided tube with a winding pitch P1 of 2.2 mm. Pandex T1180 was used as the intermediate layer. The inner diameter of the produced raw catheter was 1.30 mm and the outer diameter was 1.51 mm.

[0065] [Comparative Example 1] Catheter 1 was manufactured by coating the surface of the raw catheter with an outer layer. The outer layer was formed by covering the raw catheter with a Pandex T1180 tube having an inner diameter of 1.86 mm and an outer diameter of 1.98 mm and then heat welding the tube. When the resulting catheter 1 was bent so that one end and the other end were brought closer together, a kink occurred.

[0066] Comparative Example 2 Catheter 2 was manufactured by coating the surface of a raw catheter with a coil, and then coating that surface with an outer layer. The coil used was a round wire with a wire diameter of 0.060 mm wound at a winding pitch P2 of 5 mm. The outer layer was formed by covering the coil-coated raw catheter with a Pandex T1180 tube with an inner diameter of 1.86 mm and an outer diameter of 1.98 mm and then heat welding it. Catheter 2 did not satisfy the relationship expressed by the above formula (1) between the winding pitch P1 of the wire and the winding pitch P2 of the coil. When the obtained catheter 2 was bent so that one end and the other end were closer to each other, a kink occurred.

[0067] [Example] Catheter 3 was manufactured under the same conditions as Comparative Example 2, except that a round wire with a wire diameter of 0.060 mm wound at a winding pitch P2 of 1 mm was used as the coil. Catheter 3 had a wire winding pitch P1 and a coil winding pitch P2 that satisfied the relationship expressed by the above formula (1). When the obtained catheter 3 was bent so that one end and the other end approached each other, no kinking occurred. [Explanation of symbols]

[0068] 1 catheter 1A Extension Catheter 2. Second catheter 2a Proximal end of second catheter 2b Distal end of second catheter 2aP Opening at the proximal end of the second catheter 2bP Opening at the distal end of the 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 tubing 20b Distal end of braided tube 30 coils 30a Proximal end of coil 30b Distal end of coil 40 outer layer 50 Middle Class 60 Linear members 70 Handle member

Claims

1. a tubular member having an inner cavity extending in a longitudinal direction; a braided tube located radially outside the cylindrical member and having wires; an outer layer located radially outside the braided tube; A catheter having a coil is disposed between the braided tube and the outer layer; When viewed from the side of the catheter, the winding pitch of the wire is P1 and the winding pitch of the coil is P2, and the winding pitch P1 of the wire and the winding pitch P2 of the coil satisfy the relationship expressed by the following formula (1). P1 ≧ P2 (1)

2. the coil has a sparse portion having a winding pitch of P2 and a dense portion having a winding pitch of P3 which is smaller than P2, The catheter according to claim 1 , wherein the dense portion of the coil is disposed distally of the sparse portion of the coil in the longitudinal axis direction of the tubular member.

3. The catheter according to claim 2 , wherein the dense portion of the coil is disposed radially outside the distal end of the braided tube.

4. 2. The catheter according to claim 1, wherein the wire diameter of the coil is 0.5 to 5 times the wire diameter of the wire of the braided tube.

5. The catheter of claim 1 , wherein the coil comprises a radiopaque material.

6. 6. The catheter according to claim 5, wherein the radiopaque material has a modulus of elasticity of 190 GPa or less.

7. The catheter according to claim 1 , further comprising a linear member fixed to the tubular member and extending proximally from the tubular member.

8. 8. The catheter according to claim 7, wherein the catheter is an extension catheter that has an inner cavity extending in the longitudinal axis direction of the tubular member, is inserted into a second catheter having an opening at its distal end, and is capable of protruding from the opening of the second catheter.

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