WO2022158417A1

WO2022158417A1 - Catheter

Info

Publication number: WO2022158417A1
Application number: PCT/JP2022/001381
Authority: WO
Inventors: 健一堀場; 大冨田; 春佳杉村; 光則吉川
Original assignee: テルモ株式会社
Priority date: 2021-01-20
Filing date: 2022-01-17
Publication date: 2022-07-28
Also published as: JP2024036701A

Abstract

Provided is a catheter having an intermediate opening, the catheter being able to improve push-in strength and pull-out strength and reduce slippage and wear between components.　This catheter includes an intermediate opening that has a distal-end tube (20) and a linear shaft (30) extending from the distal-end tube (20) toward a proximal end. The distal-end tube (20) includes: an outer layer (26); an intermediate layer (25) disposed in at least a portion in the axial direction, radially inward of the outer layer (26); and a reinforcing layer (24) disposed radially inward of the middle layer (25). The linear shaft (30) is disposed between the outer layer (26) and the middle layer (25) and is radially outwardly spaced from the reinforcing layer (24).

Description

catheter

The present invention relates to a catheter having an intermediate opening having a tip tube and a linear shaft connected to the tip tube and extending proximally from the tip tube.

Guiding catheters are used to guide therapeutic catheters (balloon catheters, stent placement catheters, etc.) that are inserted into biological lumens such as blood vessels for treatment and diagnosis, etc., to the target site.

For example, in percutaneous transluminal coronary angioplasty (PTCA), which is one type of PCI that treats coronary arteries, a guide wire for a guiding catheter is inserted through the skin of the wrist or thigh into the artery, and then to the entrance of the coronary artery. reach. Next, a guiding catheter is inserted along the guidewire into the artery, and the guidewire for the guiding catheter is subsequently withdrawn to engage the coronary ostia. A thinner guidewire for a therapeutic catheter is inserted into the lumen of the guiding catheter and passed through the lesion in the coronary artery. After that, a balloon catheter is inserted along the guide wire for treatment catheter, the tip of the balloon catheter is protruded from the opening of the tip of the guiding catheter, and advanced through the coronary artery to the periphery along the guide wire that has passed through the lesion, and the balloon is inflated. Place it on the lesion and inflate the balloon for treatment.

After the tip of the guiding catheter is engaged with a predetermined site (for example, the ostium of the coronary artery), a guide extension catheter is used to smoothly advance the therapeutic catheter from the opening of the tip of the guiding catheter to the affected area within the curved or bent coronary artery. may be used (see, for example, US Pat. That is, the guide extension catheter can be inserted closer to the lesion than the guiding catheter, and can provide a stable backup force to the therapeutic catheter.

The guide extension catheter has a tip tube that moves in the lumen of the guiding catheter and protrudes from the tip opening of the guiding catheter to the distal side, and a linear tube that is connected to the tip tube and extends from the tip tube to the proximal side. A catheter with a so-called intermediate opening, here the proximal opening of the distal tube. The guide extension catheter has a short tubular portion (tip tube) because the proximal end of the tip tube is connected to the linear shaft. Therefore, in a state in which the guide wire is inserted inside the guiding catheter, the guide extension catheter can be easily inserted into and removed from the guiding catheter along the guide wire without removing the guide wire. That is, when performing such a procedure, it is necessary that the length of the guide wire protruding proximally beyond the guiding catheter is longer than the length of the tubular portion of the guide extension catheter. Since the guide extension catheter has a linear shaft, the length of the tubular portion can be shortened, so there is no need to use an unnecessarily long guide wire, which facilitates the procedure.

EP-A-2895227 EP-A-3042685

Patent Documents 1 and 2 describe guide extension catheters in which a reinforcing body is arranged in the tip tube and a linear shaft is in contact with the reinforcing body. Furthermore, it is stated that a linear shaft may be welded to the reinforcement. However, if the linear shaft is not welded to the stiffener, the tip tube and stiffener may slip relative to each other and wear may occur. Also, relative slippage between the tip tube and the stiffener reduces the push and pull strength of the catheter.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems, and to provide a catheter having an intermediate opening that can improve the pushing strength and the pulling strength, and can reduce slippage and wear between constituent members. and

A catheter having an intermediate opening for achieving the above object is a catheter having an intermediate opening having a distal tube and a linear shaft extending proximally from the distal tube, the distal tube comprising an outer layer and an outer layer and a reinforcing layer arranged radially inward of the intermediate layer, wherein the linear shaft is located between the outer layer and the intermediate layer. and is spaced radially outward from the reinforcing layer.

A catheter having an intermediate opening configured as described above can be firmly fixed by sandwiching a linear shaft between the middle layer and the outer layer, and can improve the pushing strength and the pulling strength. In addition, since the linear shaft and the reinforcing layer are separated from each other, it is possible to suppress slippage and wear between constituent members that may occur due to direct contact between the linear shaft and the reinforcing layer.

The intermediate layer may be a cylindrical collar member made of a metal material, a bridge structure member that relays the structure, or a member made of a resin material. As a result, the strength of the intermediate layer can be appropriately set, the linear shaft can be firmly fixed between the intermediate layer and the outer layer, and the pushing strength and the pulling strength can be improved.

The intermediate layer may be formed to include at least a range in which the linear shaft is arranged in the circumferential direction of the tip tube. As a result, the outer diameter of the tip tube can be reduced because the middle layer does not need to be arranged all around.

The middle layer may be formed all around in the circumferential direction of the tip tube. This eliminates the need to consider the position of the intermediate layer in the circumferential direction during manufacture, thereby facilitating manufacture. Also, the strength of the tip tube can be easily improved.

The colors of the middle layer and the outer layer may be different. As a result, it becomes easier to distinguish between the middle layer and the outer layer at the time of manufacturing.

The reinforcing layer may be formed of a coil wound with at least one wire or a braid of a plurality of wires. As a result, the tip tube can be formed thin, and the tip tube can be made difficult to kink.

The catheter may have an inner layer disposed radially inside the reinforcing layer to form an inner peripheral surface. This allows the inner layer to be formed of a material or structure that facilitates the passage of other devices through the lumen of the tip tube.

The outer layer and the middle layer may be made of a resin material. As a result, the bondability between the outer layer and the middle layer is enhanced, and the linear shaft sandwiched between the outer layer and the middle layer can be firmly fixed to the tip tube.

A distance between the linear shaft and the reinforcing layer may be 0.01 to 0.03 mm in the thickness direction of the tip tube. As a result, the linear shaft is not too far from the reinforcing layer, and the outer diameter and thickness of the tip tube can be maintained at appropriate sizes.

In order to guide the therapeutic catheter to be inserted into the guiding catheter, the catheter protrudes from the tip opening of the guiding catheter and is advanced through the coronary artery to the periphery along the therapeutic catheter. and a guide extension catheter for arranging a treatment portion for performing treatment on a lesion portion provided on the treatment catheter. As a result, when the operator manipulates the linear shaft located outside the body, the guide extension catheter can effectively transmit pushing force, withdrawal force and rotational force to the tip tube, and the tip can be used during surgery. Separation of the tube and the linear shaft can be prevented.

FIG. 2 is a plan view showing a guide extension catheter, a dilator, and a guiding catheter, which are catheters having intermediate openings according to the present embodiment. It is a figure which shows a guide extension catheter, (A) is a side view, (B) is a top view, (C) is a partially enlarged view of a linear shaft. FIG. 2 shows a guide extension catheter, (A) is a cross-sectional view along line AA in FIG. 2, (B) is a cross-sectional view along line BB in FIG. 2, and (C) is C- in FIG. It is sectional drawing which follows C line. It is a figure which shows a dilator, (A) is a side view, (B) is a top view, (C) is a partially enlarged view of a dilator linear shaft. is. FIG. 5 is a cross-sectional view taken along line DD of FIG. 4; FIG. 4 is a side view showing a catheter assembly in which a dilator is assembled with a guide extension catheter; FIG. 4A is a side view of a catheter having an intermediate opening showing a first modified example, and FIG. FIG. 11 is a plan view of a catheter having an intermediate opening showing a second modification; FIG. 11 is a side view of a catheter and dilator having an intermediate opening showing a third modification; FIG. 10 is a side view of a catheter and dilator having an intermediate opening showing a fourth modification; FIG. 11 is a side view of a dilator showing a fifth modified example;

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the dimensional ratios in the drawings may be exaggerated for convenience of explanation and may differ from the actual ratios. In this specification, the side of the device that is inserted into a blood vessel is called the "distal side", and the side that is manipulated is called the "proximal side".

As shown in FIG. 1, the catheter having an intermediate opening according to this embodiment is inserted into a guiding catheter 100 having a distal soft tip 100A, protrudes from a distal opening 101 of the guiding catheter 100, and guides the therapeutic catheter. 1 is a guide extension catheter 10 used to extend a tube for endoscopic surgery from a guiding catheter 100 to the distal side. A rapid exchange dilator 50 can be inserted into the guide extension catheter 10 .

As shown in FIGS. 1 to 3, the guide extension catheter 10 includes a tubular tip tube 20 and a linear shaft 30 connected to the tip tube 20 and extending from the tip tube 20 to the proximal side.

The tip tube 20 can move through the lumen of the guiding catheter 100 and protrude from the tip opening 101 of the guiding catheter 100 to the tip side. The tip tube 20 thereby provides a continuous lumen from the guiding catheter 100 . That is, in the procedure, the tip tube 20 of the guide extension catheter 10 is inserted closer to the lesion site than the guiding catheter 100, so that the treatment catheter can be stably backed up.

The distal tube 20 is a tubular body having a lumen penetrating from the distal end to the proximal end, and includes a tubular portion 21 arranged on the distal side and a semi-tubular portion 22 arranged on the proximal side of the tubular portion 21 . ing. The tubular portion 21 is formed in a circular tubular shape by providing a material in a range of 360 degrees in the circumferential direction. The semi-pipe portion 22 is formed in a half-pipe shape by providing material in a range of approximately 180 degrees in the circumferential direction. The angular range in which the material of the semi-tube portion 22 is provided is not particularly limited as long as it is less than 360 degrees, and may be less than 180 degrees, for example. Alternatively, the half tube portion 22 may not be provided. The axial length of the tubular portion 21 is not particularly limited, but is, for example, 200 mm to 400 mm. The axial length of the semi-tubular portion 22 is not particularly limited, but is, for example, 5 mm to 200 mm. The inner diameter of the tip tube 20 is not particularly limited, but is, for example, 1.3 mm to 1.5 mm. The outer diameter of the tip tube 20 is not particularly limited, but is, for example, 1.55 mm to 1.75 mm.

It is preferable that the rigidity of the distal tube 20 decreases stepwise or gradually from the proximal side toward the distal side. As a result, the distal end tube 20 has a softer structure with less rigidity toward the distal end, so that flexibility can be imparted to the distal end portion and high pushability can be imparted to the proximal end portion. Note that the rigidity of the distal tube 20 does not have to change from the proximal side toward the distal side. The distal end tube 20 has a distal tip 21A formed of a flexible material such as polyurethane at its distal end.

The distal tube 20 includes an inner layer 23 , a reinforcing layer 24 , a middle layer 25 , an outer layer 26 , a distal marker 27 and a proximal marker 28 . Tubular portion 21 is formed by inner layer 23 , reinforcing layer 24 , middle layer 25 , outer layer 26 , distal marker 27 and proximal marker 28 . The semi-tube portion 22 is formed by an inner layer 23, an intermediate layer 25 and an outer layer 26, but may be formed by the inner layer 23 and the outer layer 26 or the outer layer 26 alone.

The inner layer 23 is a layer that forms the inner peripheral surfaces of the tubular portion 21 and the semi-tubular portion 22 of the tip tube 20 . The inner layer 23 is arranged radially inside the reinforcing layer 24 . The inner layer 23 is preferably made of a low-friction material so that the guide wire, therapeutic catheter, dilator 50 or the like can easily slide inside. The low-friction material is, for example, fluorine-based resin such as PTFE (polytetrafluoroethylene), PFA (tetrafluoroethylene-perfluoroalkoxyethylene copolymer), or silicone resin, but is not limited to these. The thickness of the inner layer 23 is not particularly limited, but is, for example, 0.0001 mm to 0.1 mm, preferably 0.005 mm to 0.05 mm, and more preferably 0.01 mm to 0.03 mm.

The reinforcing layer 24 is formed of a coil formed by spirally winding at least one wire or a plurality of braids formed by braiding a plurality of wires in order to reinforce the tubular portion 21 of the tip tube 20 . The reinforcing layer 24 is arranged radially outside the inner layer 23 and radially inside the intermediate layer 25 . Coils and braids are made of wires made of metal materials such as stainless steel and tungsten wires. It is not particularly limited and is set as appropriate. When the reinforcing layer 24 is formed of a coil, the crossing angle between the long axis and the wire is not particularly limited, and may be set appropriately and may be constant or variable along the long axis direction. When the reinforcing layer 24 is formed by a braid, the number of picks with one of the stitches as a pick, the number of ends that is the number of strands included in one pick, and the picks in one round The number of spindles, which is the number of spindles, is set as appropriate. Also, the shape and dimensions of the reinforcing wire may vary depending on the winding direction. The wire rods forming the coils or braids of the reinforcing layer 24 may be arranged at a sparse pitch with gaps or at a fine pitch without gaps. The reinforcing layer 24 can be used as a contrast marker that improves contrast when the tungsten wires are arranged at a dense pitch.

The intermediate layer 25 is a layer that surrounds the outer peripheral surfaces of the inner layer 23 and the reinforcing layer 24 of the tubular portion 21 and the semi-tubular portion 22 of the tip tube 20 . The middle layer 25 is arranged radially outside the reinforcing layer 24 and radially inside the outer layer 26 . The middle layer 25 is joined to the inner layer 23 in the range where the reinforcing layer 24 is not provided. The middle layer 25 is arranged radially inside the linear shaft 30 . The intermediate layer 25 may be formed all around in the circumferential direction of the tip tube 20, or may be formed partially including at least the range where the linear shaft 30 is arranged. The middle layer 25 is partially formed in the semi-tube portion 22 in the circumferential direction, but the half-tube portion 22 may not be provided with the middle layer 25 . Although it is formed all around the tubular portion 21 in the circumferential direction, it may also be partially formed in the tubular portion 21 in the circumferential direction.

The constituent material of the middle layer 25 is not particularly limited, but for example, various thermoplastics such as styrene, polyolefin, polyurethane, polyester, polyamide, polybutadiene, transpolyisoprene, fluororubber, and chlorinated polyethylene. Elastomers, polyether ketones, polyimides, etc. may be used, and one or more of these may be used in combination (polymer alloys, polymer blends, laminates, etc.). Alternatively, among various elastomers, polyester elastomers, polyamide elastomers, and the like can be preferably used. The thickness of the intermediate layer 25 is not particularly limited, but is, for example, 0.0001 mm to 0.1 mm, preferably 0.005 mm to 0.05 mm, more preferably 0.01 mm to 0.03 mm. The middle layer 25 may also include an X-opaque material (contrast agent) in the material. Radiopaque metals include, for example, gold, platinum, silver, bismuth, tungsten or alloys of two or more of these (eg platinum-tungsten), barium sulfate, or alloys with other metals (eg gold -iridium, platinum-iridium, platinum-nickel) and the like. The material of the intermediate layer 25 may be stainless steel, nickel-titanium alloy, gold, platinum, silver, bismuth, tungsten, or an alloy of two or more of these (eg, platinum-tungsten), barium sulfate, or others. metal (for example, gold-iridium, platinum-iridium, platinum-nickel) may be used. Well, the resin may be an adhesive.

The outer layer 26 is a layer that forms the outer peripheral surfaces of the tubular portion 21 and the semi-tubular portion 22 of the tip tube 20 . Outer layer 26 surrounds the outer peripheral surface of middle layer 25 of tubular portion 21 and semi-tubular portion 22 . That is, the outer layer 26 is arranged radially outside the middle layer 25 . Outer layer 26 also surrounds the outer peripheral surface of distal marker 27 and proximal marker 28 provided on tubular portion 21 . The outer layer 26 is fixed to the middle layer 25 by sandwiching the linear shaft 30 therebetween. Therefore, the linear shaft 30 does not directly contact the reinforcing layer 24 . When the linear shaft 30 and the reinforcing layer 24 are made of a metal material, they are likely to slip and wear when they come into contact with each other. On the other hand, since the intermediate layer 25 made of a resin material is provided between the reinforcing layer 24 and the linear shaft 30, the reinforcing layer 24 and the linear shaft 30 are fixed to the resin material, respectively. Slippage and abrasion of the reinforcing layer 24 can be suppressed.

The outer layer 26 has protrusions 29 on the outer surface of the portion where the linear shaft 30 is embedded. The protrusion 29 protrudes radially outward in a cross section perpendicular to the axial center of the tip tube 20 . The convex portion 29 is formed at a position corresponding to the linear shaft 30 that is bent so as to be folded back. Therefore, the outer layer 26 does not become too thin at the portion where the linear shaft 30 is embedded inside the tip tube 20 . Therefore, the strength of the tip tube 20 can be improved, the linear shaft 30 can be prevented from coming off from the tip tube 20, the need to make the linear shaft 30 excessively thin, and the push-in strength and pull-out strength of the guide extension catheter 10 can be eliminated. can be improved.

The outer layer 26 has, in a cross section orthogonal to the axial center of the tip tube 20, a portion where two convex portions 29 are formed and a portion where one convex portion 29 is formed. The part where two protrusions 29 are formed is arranged on the tip side of the part where one protrusion 29 is formed. In the portion where the two protrusions 29 are formed, the portion of the distal end portion of the linear shaft 30 that is folded back and exists so as to line up the two wire rods is embedded. The portion where one convex portion 29 is formed is closer to the base end than the portion where the distal end portion of the linear shaft 30 is folded back, and the portion where one wire rod exists is embedded. A concave portion 29A is formed between the two convex portions 29 . The two projections 29 are continuously connected at the tip of the linear shaft 30 where the semicircular portion 34 described later is located. Note that the convex portion 29 may not be formed.

The constituent material of the outer layer 26 is not particularly limited, but for example, various thermoplastics such as styrene, polyolefin, polyurethane, polyester, polyamide, polybutadiene, transpolyisoprene, fluororubber, and chlorinated polyethylene. Elastomers, polyether ketones, polyimides, etc. may be used, and one or more of these may be used in combination (polymer alloys, polymer blends, laminates, etc.). Alternatively, among various elastomers, polyester elastomers, polyamide elastomers, and the like can be preferably used. The thickness of the outer layer 26 is not particularly limited, but is, for example, 0.0001 mm to 0.1 mm, preferably 0.005 mm to 0.05 mm, more preferably 0.01 mm to 0.03 mm. is. The outer peripheral surface of the outer layer 26 may be coated with a lubricious material in order to improve passageability with the blood vessel and the inner wall surface of the guiding catheter 100 . Lubricating materials include epoxy group-containing monomers such as glycidyl acrylate, glycidyl methacrylate, 3,4-epoxycyclohexylmethyl acrylate, 3,4-epoxycyclohexylmethyl methacrylate, β-methylglycidyl methacrylate, allyl glycidyl ether, and N - copolymers with hydrophilic monomers such as methylacrylamide, N,N-dimethylacrylamide and acrylamide; (co)polymers composed of the above hydrophilic monomers; celluloses such as hydroxypropyl cellulose and carboxymethyl cellulose high-molecular substances; polysaccharides, polyvinyl alcohol, methyl vinyl ether-maleic anhydride copolymer, water-soluble polyamide, poly(2-hydroxyethyl (meth)acrylate), polyethylene glycol, polyacrylamide, polyvinylpyrrolidone and the like. Hydrophilic lubricating polymers such as polyacrylamide copolymers containing acrylamide are preferred, and hydrophobic lubricating polymers such as fluorine-based resins may also be used.

The outer layer 26 and the middle layer 25 are made of, for example, a resin material instead of a metal material. Thereby, the outer layer 26 and the middle layer 25 can have high bonding strength. Therefore, the outer layer 26 and the intermediate layer 25 can firmly fix the sandwiched linear shaft 30 to the tip tube 20 . Also, the outer layer 26 and the middle layer 25 may be made of the same material, or may be made of different colors or different hardnesses.

The distal marker 27 and the proximal marker 28 contain radiopaque metal that is visible under fluoroscopy. The distal end marker 27 and the proximal end marker 28 are, for example, ring-shaped members, but may be members with a C-shaped cross section, coils, or the like. Radiopaque metals include, for example, gold, platinum, silver, bismuth, tungsten or alloys of two or more of these (eg platinum-tungsten), barium sulfate, or alloys with other metals (eg gold -iridium, platinum-iridium, platinum-nickel) and the like. When distal marker 27 and proximal marker 28 contain radiopaque metal, the operator can grasp the position of distal tube 20 inserted into the body under radiography.

The tip marker 27 is sandwiched between the inner layer 23 and the outer layer 26 at the tip of the tubular portion 21 . The position where the tip marker 27 is arranged is not limited to between the inner layer 23 and the outer layer 26. good too. The tip marker 27 is arranged on the tip side of the reinforcing layer 24 . Therefore, tip marker 27 does not overlap reinforcing layer 24 in the axial direction of tip tube 20 . As a result, the thickness of the tip tube 20 can be reduced and the outer diameter can be reduced. Note that the tip marker 27 may overlap the reinforcing layer 24 in the axial direction of the tip tube 20 . Also, the tip marker 27 may not be provided.

The proximal marker 28 is sandwiched between the middle layer 25 and the outer layer 26 at the proximal end of the tubular portion 21 . In addition, the position where the base end marker 28 is arranged is not limited to between the middle layer 25 and the outer layer 26, and may be arranged between the inner layer 23 and the middle layer 25, between the inner layer 23 and the outer layer 26, or outside the outer layer 26, for example. may The proximal marker 28 is located proximal to the reinforcing layer 24 . Therefore, proximal marker 28 does not overlap reinforcing layer 24 in the axial direction of distal tube 20 . As a result, the thickness of the tip tube 20 can be reduced and the outer diameter can be reduced. Note that the proximal end marker 28 may overlap the reinforcing layer 24 in the axial direction of the distal tube 20 . Also, the proximal marker 28 may not be provided.

The linear shaft 30 is a flexible wire material, and may be a round wire, a flat wire, or an arc wire, but a round wire is preferable. there is The linear shaft 30 includes a linear base portion 31 and a shaped distal end portion 32 disposed on the distal end side of the base portion 31 . In addition, since the base 31 has flexibility and bends flexibly, it does not always need to be straight. The tip shape portion 32 includes an intermediate straight portion 33 extending from the base portion 31 to the tip side, a semicircular portion 34 arranged on the tip side of the intermediate straight portion 33, and the intermediate straight portion 33 arranged from the semicircular portion 34. and a tip straight portion 35 extending to the side opposite to the side of the tip.

The intermediate straight portion 33 reaches from the base end surface of the semi-tubular portion 22 to the base end portion of the tubular portion 21 . Therefore, the distal end of the intermediate straight portion 33 is positioned at the tubular portion 21 . The intermediate straight portion 33 is inclined at a minute angle exceeding 0 degrees with respect to an extension line L1 located on the axis of the base portion 31 and extending from the base portion 31 toward the distal end side. Therefore, the intermediate straight portion 33 is arranged to be shifted to one side from the extension line L1. Alternatively, the intermediate straight portion 33 may be parallel to or on the extension line L1.

The proximal end of the intermediate straight portion 33 may be located on the proximal side of the proximal end of the semi-tubular portion 22 or may be located on the distal side of the semi-tubular portion 22 . The starting point at which the intermediate straight portion 33 is positioned on the axis of the base portion 31 and inclined with respect to the extension line L1 extending from the base portion 31 to the distal side may be inside the semi-tubular portion 22 or inside the tubular portion 21 . may

The semicircular portion 34 is bent by changing the direction by about 180 degrees so as to draw a substantially semicircular shape at the proximal end of the tubular portion 21 . The semicircular portion 34 is arranged so as to intersect the extension line L1. Note that the semicircular portion 34 does not have to strictly intersect the extension line. The semicircular portion 34 is arranged at a position overlapping the reinforcing layer 24 in the axial direction of the tip tube 20 . That is, both the semicircular portion 34 and the reinforcing layer 24 are provided within a predetermined range in the axial direction of the tip tube 20 . The distal linear portion 35 extends from the end of the tubular portion 21 opposite to the side in contact with the intermediate linear portion 33 toward the proximal end. The straight tip portion 35 is substantially parallel to the extension line L1, but does not have to be strictly parallel. An extension line L1 is arranged between the intermediate straight portion 33 and the tip straight portion 35 . The intermediate straight portion 33, the semicircular portion 34 and the tip straight portion 35 are arranged on the same plane. A terminal end portion 36 located on the opposite side of the straight tip portion 35 from the side in contact with the semicircular portion 34 is located in the tubular portion 21 . It should be noted that the terminal end portion 36 may be located at the half tube portion 22 . The terminal end portion 36 is arranged on the proximal side of the reinforcing layer 24 in the axial direction of the distal tube 20 . The radius of curvature of the semi-circular portion 34 may not be constant, and may be semi-elliptical or the direction of the semi-circular portion may exceed 180 degrees, or conversely may be less than 180 degrees.

The portion of the linear shaft 30 embedded in the tip tube 20 is arranged between the middle layer 25 and the outer layer 26 and is spaced radially outward from the reinforcing layer 24 . The distance between the linear shaft 30 and the reinforcing layer 24 is not particularly limited, but is, for example, 0.01 to 0.03 mm in the thickness direction of the tip tube 20 (the radial direction of the tubular portion 21). The linear shaft 30 preferably does not contact the reinforcing layer 24 at all, but may partially contact the tip tube 20 in a part of the axial direction.

The linear shaft 30 may be coated with a low-friction material on all or at least part of the portion exposed to the outside so that it can slide on the inner wall surface of the guiding catheter 100 with low friction. The low-friction material is, for example, fluorine-based resin or silicone resin, but is not limited to these. All or at least a portion of the portion of the linear shaft 30 exposed to the outside may be coated with a lubricating material in order to improve slidability with the inner wall surface of the guiding catheter 100 .

As shown in FIG. 2B, the linear shaft 30 has a first linear portion 40 with a constant outer diameter, a first tapered portion 41 with a decreasing outer diameter, and a first tapered portion 41 with a decreasing outer diameter. It has a second linear portion 42 with a constant outer diameter, a second tapered portion 43 with a decreasing outer diameter, and a third linear portion 44 with a constant outer diameter. The first straight portion 40 forms the base portion 31 . The first tapered portion 41 forms a portion including the boundary between the base portion 31 and the intermediate straight portion 33 . Part of the base end side of the second straight portion 42 , the second tapered portion 43 , and the third straight portion 44 forms the intermediate straight portion 33 . Other portions of the third straight portion 44 form the semicircular portion 34 and the tip straight portion 35 . Alternatively, the tip straight portion 35, the semicircular portion 34, and the intermediate straight portion 33 may be located on the tip side of the second taper portion 43, that is, the tip shape portion 32 may have a smaller outer diameter than the base portion 31 and may be constant. . The linear shaft 30 is connected to the tip tube 20 after the tip shape portion 32 is shaped into a predetermined shape.

The linear shaft 30 is adhered to the outer peripheral surface or inner peripheral surface of the base end marker 28 with an adhesive. The linear shaft 30 is adhered to the base end marker 28 at, for example, the intermediate straight portion 33 and the distal straight portion 35, but the sites to be adhered are not particularly limited. The adhered proximal marker 28 and linear shaft 30 can be incorporated in the adhered state at the time of manufacture, which facilitates manufacture. Further, when the linear shaft 30 and the base end marker 28 are fixed by caulking, welding, or the like, the linear shaft 30 and the base end marker 28 are likely to be deformed. In contrast, when the base end marker 28 and the linear shaft 30 are fixed by adhesion, they are less likely to be deformed. Therefore, the shape of the catheter can be stabilized and can be manufactured at low cost. The linear shaft 30 and the base end marker 28 may be fixed by a method other than adhesion, for example, by caulking, welding, or the like.

Although the outer diameter of the linear shaft 30 is not particularly limited, it is, for example, 0.05 mm to 1 mm, and may have a constant diameter from the distal end to the proximal end. The axial length of the base portion 31 of the linear shaft 30 is not particularly limited, but is, for example, 1100 mm to 1300 mm. Although the material of the linear shaft 30 is not particularly limited, for example, stainless steel, nickel-titanium alloy, etc. can be suitably used. Further, the cross-sectional shape of the linear shaft 30 is not limited to circular, and may be, for example, rectangular, square, elliptical, or the like, and may have different shapes depending on the part. The linear shaft 30 may have depth markers visible on the base 31 for tracking the length of insertion into the guiding catheter 100 .

The rapid exchange dilator 50, as shown in FIGS. 4 and 5, includes a tubular dilator tip tube 60 and a linear dilator shaft 70 connected to and extending proximally from the dilator tip tube 60. and That is, like the guide extension catheter 10, the dilator 50 is also a catheter having an intermediate opening with a tip tube and a linear shaft. The dilator 50 can be called an instrument that is inserted into the coronary artery together with the guide extension catheter 10 and smoothly guided to a lesion such as a stenosis that occurs in the coronary artery.

Alternatively, the dilator 50 can be called an instrument that is inserted into the coronary artery together with the guide extension catheter 10 and smoothly guides it beyond a lesion such as a stenosis that occurs in the coronary artery, thereby dilating the stenosis.

The dilator distal tube 60 is a tubular body having a lumen penetrating from the distal end to the proximal end. and an inclined portion 63 arranged on the base end side of the tubular portion 62 . The tip tapered portion 61 is tapered toward the tip side.

Alternatively, the tip tapered portion 61 may taper toward the tip side, and may have a cylindrical portion with a constant outer diameter at the tip. Tubular portion 62 is a cylinder having a uniform outer diameter and inner diameter. The outer diameter of the tubular portion 62 is smaller than the inner diameter of the tip tube 20 by, for example, 0.05 mm. This allows the tubular portion 62 to move smoothly through the lumen of the distal tube 20 . The inner diameter of the tubular portion 62 is larger than the outer diameter of the inserted guidewire. This allows the tubular portion 62 to move smoothly along the guidewire. The inclined portion 63 has a base end surface that is inclined with respect to a cross section perpendicular to the axis. Note that the inclined portion 63 may not be provided. Although the axial length of the tip tapered portion 61 is not particularly limited, it is, for example, 3 mm to 30 mm. The overall axial length of the dilator tip tube 60 is not particularly limited, but is, for example, 100 mm to 450 mm. Dilator tip tube 60 is preferably flexible with some degree of flexibility. For this reason, the constituent material of the dilator tip tube 60 is, for example, various thermoplastics such as styrene, polyolefin, polyurethane, polyester, polyamide, polybutadiene, transpolyisoprene, fluororubber, and chlorinated polyethylene. Elastomers, polyether ketones, polyimides, etc. may be used, and one or more of these may be used in combination (polymer alloys, polymer blends, laminates, etc.). Alternatively, among various elastomers, for example, polyurethane elastomers, polyester elastomers, polyamide elastomers, etc. can be preferably used. The dilator tip tube 60 may include an X-opaque material (contrast agent) as described above.

Alternatively, the dilator tip tube 60 may include the X-opaque material (contrast agent) described above in the material, or may have markers made of X-ray opaque metal. Radiopaque metals include, for example, gold, platinum, silver, bismuth, tungsten or alloys of two or more of these (eg platinum-tungsten), barium sulfate, or alloys with other metals (eg gold -iridium, platinum-iridium, platinum-nickel) and the like. If a distal marker or a proximal marker (not shown) containing radiopaque metal is provided, the operator can grasp the position of the dilator distal tube 60 inserted into the body under radiography. can do.

The dilator tip tube 60 is formed, for example, by insert-molding the dilator linear shaft 70 in a mold.

The dilator linear shaft 70 is a flexible wire, is connected to the dilator tip tube 60, and extends from the dilator tip tube 60 to the proximal side. The dilator linear shaft 70 includes a linear shaft base portion 71 and a shaft tip shape portion 72 arranged and shaped on the tip side of the shaft base portion 71 . In addition, since the shaft base portion 71 has flexibility and bends flexibly, it does not always need to be straight. The shaft tip shape portion 72 includes a shaft intermediate straight portion 73 extending from the shaft base portion 71 to the tip side, a shaft semicircular portion 74 disposed on the tip side of the shaft intermediate straight portion 73, and a shaft extending from the shaft semicircular portion 74. and a shaft tip straight portion 75 extending to the side opposite to the side where the intermediate straight portion 73 is provided.

The shaft intermediate straight portion 73 reaches the cylindrical portion 62 from the proximal end surface of the portion of the inclined portion 63 of the dilator tip tube 60 that protrudes toward the proximal end side. Therefore, the tip of the shaft intermediate straight portion 73 is positioned at the cylindrical portion 62 . The shaft intermediate straight portion 73 is positioned on the axis of the shaft base portion 71 and is inclined at a minute angle exceeding 0 degrees with respect to an extension line L2 extending from the shaft base portion 71 to the tip side. Therefore, the shaft intermediate straight portion 73 is arranged to be shifted to one side from the extension line L2.

The shaft semicircular portion 74 is bent by changing its direction by about 180 degrees so as to draw a substantially semicircular shape at the proximal end of the cylindrical portion 62 . The shaft semicircular portion 74 is arranged to intersect the extension line L2. It should be noted that the shaft semicircular portion 74 does not have to strictly intersect the extension line L2. The shaft distal straight portion 75 extends from the end of the shaft semicircular portion 74 opposite to the side in contact with the shaft intermediate straight portion 73 toward the proximal side. The shaft tip straight portion 75 is substantially parallel to the extension line L2, but does not have to be strictly parallel. An extension line L2 is arranged between the shaft intermediate straight portion 73 and the shaft tip straight portion 75 . The shaft intermediate straight portion 73, the shaft semicircular portion 74, and the shaft tip straight portion 75 are arranged on the same plane. A shaft terminal end portion 76 on the side opposite to the side of the shaft tip straight portion 75 in contact with the shaft semicircular portion 74 is located on the cylindrical portion 62 or the inclined portion 63 . The shaft semi-circular portion 74 may not have a constant radius of curvature, may be semi-elliptical, or may have a direction greater than 180 degrees or less than 180 degrees.

As shown in FIG. 4B, the dilator linear shaft 70 has a dilator linear portion 80 having a constant outer diameter and a dilator linear shaft 70 extending from the distal end of the dilator linear portion 80 toward the distal end side from the base end side. and a dilator taper portion 81 in which the outer diameter decreases to the tip of the dilator. The dilator straight portion 80 forms the shaft base portion 71 . The dilator tapered portion 81 forms a tip portion of the shaft base portion 71 , a shaft intermediate straight portion 73 , a shaft semicircular portion 74 and a shaft tip straight portion 75 . The boundary between the dilator straight portion 80 and the dilator tapered portion 81 is arranged on the proximal side of the dilator distal tube 60 , but may be arranged on the proximal end of the dilator distal tube 60 or inside the dilator distal tube 60 . The dilator linear shaft 70 is connected to the dilator tip tube 60 after the shaft tip profile 72 is shaped into a predetermined shape.

Although the outer diameter of the dilator linear shaft 70 is not particularly limited, it is, for example, 0.05 mm to 1 mm. The axial length of the base portion 31 of the dilator linear shaft 70 is not particularly limited, but is, for example, 1000 mm to 1400 mm. The constituent material of the dilator linear shaft 70 is not particularly limited, but for example, stainless steel, nickel-titanium alloy, etc. can be suitably used. Moreover, the cross-sectional shape of the dilator linear shaft 70 is not limited to a circular shape, and may be, for example, rectangular, square, elliptical, or the like, and may have different shapes depending on the part. The dilator linear shaft 70 may have depth markers that can be visually confirmed to track the length of insertion into the guiding catheter 100 .

The guide extension catheter 10 and the dilator 50 can be used with the dilator 50 inserted into the guide extension catheter 10 as shown in FIG. Guide extension catheter 10 and dilator 50 may be packaged in a combined catheter assembly. As a result, the convenience of the procedure is improved, and the procedure can be performed immediately after opening the package.

The dilator tip tube 60 can move through the lumen of the tip tube 20 of the guide extension catheter 10 and partially protrude from the tip opening 201 of the tip tube 20 to the tip side. At this time, the tip tapered portion 61 of the dilator tip tube 60 protrudes from the tip opening 201 of the tip tube 20 to the tip side. After engaging the tip of the guiding catheter 100 with the ostium of the coronary artery, the operator projects the guide extension catheter 10 with the dilator 50 inserted through the tip opening 101 of the guiding catheter 100 . At this time, since the clearance between the outer peripheral surface of the dilator distal tube 60 and the inner peripheral surface of the distal tube 20 is small, the outer peripheral surface of the dilator distal tube 60 and the inner peripheral surface of the distal tube 20 are in contact with each other at a small surface. Similarly, since the clearance between the inner peripheral surface of the dilator distal tube 60 and the outer peripheral surface of the guidewire is small, the outer peripheral surface of the dilator distal tube 60 and the inner peripheral surface of the distal tube 20 are in contact with each other at a small surface.

Therefore, the dilator tip tube 60 plays a role of smoothly guiding the guide extension catheter 10 to the target position along the guidewire. The target position may be guided to a position in front of the lesion or beyond the lesion. Next, the dilator tip tube 60 is removed from the guide extension catheter 10 while fixing the position of the guide wire. Subsequently, the therapeutic catheter is passed through the lumen of the guiding catheter 100 and the guide extension catheter 10 to reach the lesion along the guidewire. After that, the operator can treat the lesion (for example, expansion with a balloon or placement of a stent) using the treatment catheter.

As described above, the catheter having an intermediate opening according to the present embodiment is a catheter having an intermediate opening having the distal tube 20 and the linear shaft 30 extending proximally from the distal tube 20. has an outer layer 26, an intermediate layer 25 disposed radially inward of the outer layer 26 at least in part in the axial direction, and a reinforcing layer 24 disposed radially inward of the intermediate layer 25, and a linear shaft 30 is located between outer layer 26 and middle layer 25 and is spaced radially outwardly from reinforcing layer 24 .

A catheter having an intermediate opening configured as described above can be firmly fixed by sandwiching the linear shaft 30 between the middle layer 25 and the outer layer 26, and can improve the pushing strength and the pulling strength. In addition, since the linear shaft 30 and the reinforcing layer 24 are separated from each other, it is possible to suppress slippage and wear between constituent members that may occur due to direct contact between the linear shaft 30 and the reinforcing layer 24 . In particular, when the linear shaft 30 and the reinforcing layer 24 are made of metal, it is possible to effectively suppress slippage and wear caused by direct contact between the linear shaft 30 and the reinforcing layer 24 .

Further, the middle layer 25 may be a cylindrical collar member made of a metal material, a bridge structure member that relays the structure, or a member made of a resin material. Thereby, the strength of the middle layer 25 can be appropriately set, the linear shaft 30 can be firmly fixed between the middle layer 25 and the outer layer 26, and the pushing strength and the pulling strength can be improved.

In addition, the intermediate layer 25 is formed including at least a range in which the linear shaft 30 is arranged in the circumferential direction of the tip tube 20 . As a result, the outer diameter of the tip tube 20 can be reduced because the middle layer 25 does not need to be arranged all around.

Also, the colors of the middle layer 25 and the outer layer 26 may be different. This makes it easier to distinguish between the middle layer 25 and the outer layer 26 during manufacturing, which makes it easier to prevent mix-ups during manufacturing and facilitates manufacturing.

Also, the reinforcing layer 24 is formed of a coil wound with at least one wire or a braid of a plurality of wires. As a result, the tip tube 20 can be formed thin, and the tip tube 20 can be made difficult to kink.

The catheter having an intermediate opening also has an inner layer 23 arranged radially inside the reinforcing layer 24 to form an inner peripheral surface. This allows the inner layer 23 to be formed of a material or structure that allows other devices to easily pass through the lumen of the tip tube 20 .

Also, the outer layer 26 and the middle layer 25 may be made of a resin material. As a result, the bondability between the outer layer 26 and the intermediate layer 25 is enhanced, and the linear shaft 30 sandwiched between the outer layer 26 and the intermediate layer 25 can be firmly fixed to the tip tube 20 .

Also, the distance between the linear shaft 30 and the reinforcing layer 24 may be 0.01 to 0.03 mm in the thickness direction of the tip tube 20 . As a result, the linear shaft 30 is not too far from the reinforcing layer 24, and the outer diameter and thickness of the tip tube 20 can be maintained at appropriate sizes.

In order to guide the therapeutic catheter inserted into the guiding catheter 100, the catheter having an intermediate opening protrudes from the distal end opening 101 of the guiding catheter 100 and moves along the coronary artery along the therapeutic catheter. The guide extension catheter 10 may be a guide extension catheter 10 for advancing the inner part to the periphery and arranging the treatment part provided on the treatment catheter to the lesion for treatment. As a result, when the operator manipulates the linear shaft 30 located outside the body, the guide extension catheter 10 can effectively transmit a pushing force, a pulling force, and a rotating force to the distal tube 20, and can be used during the operation. It is possible to prevent the tip tube 20 and the linear shaft 30 from being separated during the operation. The treatment portion provided in the treatment catheter for treatment is, for example, a balloon or a stent.

In order to guide the therapeutic catheter inserted into the guiding catheter 100, the catheter having an intermediate opening protrudes from the distal end opening 101 of the guiding catheter 100 and moves along the coronary artery along the therapeutic catheter. It may be a rapid exchange type dilator 50 inserted into the guide extension catheter 10 for arranging the treatment portion provided on the treatment catheter to the affected area. As a result, when the operator manipulates the dilator linear shaft 70 located outside the body, the dilator 50 can effectively transmit the pushing force, the pulling force, and the rotational force to the dilator distal tube 60, and can be used during the operation. Separation of the dilator tip tube 60 and the dilator linear shaft 70 can be prevented.

It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made by those skilled in the art within the technical concept of the present invention. For example, as in a first modified example shown in FIG. 7, the axial center of the tip shape portion 32 may be three-dimensionally arranged beyond the same plane. For example, terminal end 36 is positioned away from the plane in which intermediate straight portion 33 and semi-circular portion 34 lie. As a result, the intermediate straight portion 33, the semicircular portion 34, and the distal straight portion 35 of the linear shaft 30 can be efficiently arranged within the limited thickness range of the tip tube 20. You can control the increase. The intermediate layer 25 may be arranged between the three-dimensional tip shape portion 32 of the linear shaft 30 and the reinforcing layer 24 so that the tip shape portion 32 is separated from the reinforcing layer 24 .

Further, as in the second modified example shown in FIG. 8, the middle layer 25 may be formed all around the entire length and circumferential direction of the tip tube 20 . That is, the middle layer 25 may be a circular tube, and the cross section perpendicular to the axial center of the tip tube 20 may be circular at all positions in the axial direction. This eliminates the need to consider the position of the middle layer 25 in the circumferential direction during manufacture, thereby facilitating manufacture. Also, the strength of the tip tube 20 can be easily improved. The inner and outer diameters of the middle layer 25 may be uniform in the axial direction or may vary.

In addition, the middle layer 25 may have a C-shaped cross section perpendicular to the axial center of the distal tube 20 at all positions in the axial direction of the distal tube 20 .

Further, the middle layer 25 may be a cylindrical collar member made of a metal material or another bridge structure that relays the structure, and the middle layer 25 may be made of a resin material.

9, the distal end tube 20 of the guide extension catheter 10 includes a proximal end lumen 20A having a substantially uniform inner diameter, and a distal end disposed on the distal side of the proximal end lumen 20A. A distal lumen 20B may be provided having a laterally tapering, decreasing inner diameter. As a result, the distal end tube 20 accommodates a part of the distal tapered portion 61 of the dilator 50 in the distal lumen 20B, and the cylindrical portion 62 arranged on the proximal side of the distal tapered portion 61 is inserted into the proximal lumen 20A. can be accommodated in Since the distal end tube 20 can have the tubular portion 62 having a larger outer diameter than normal in the proximal end lumen 20A, the pushability and penetrating force of the dilator distal end tube 60 can be improved.

Further, as in the fourth modification shown in FIG. 10, the dilator distal tube 60 of the dilator 50 may have a proximal opening 64 that tapers toward the proximal side. As a result, the insertability of the guide wire into the dilator distal tube 60 can be improved. The dilator tip tube 60 may also have a large diameter portion 65 at its proximal end that has a larger outer diameter than the distal end. The dilator 50 can be prevented from protruding too much from the guide extension catheter 10 by abutting the large diameter portion 65 against the distal end tube 20 of the guide extension catheter 10 to interfere with it.

Further, as in the fifth modification shown in FIG. 11, the dilator tip tube 60 of the dilator 50 may have a plurality of X-ray contrast markers 66 arranged at predetermined intervals (for example, 5 mm intervals) in the axial direction. . Thereby, the length can be estimated based on the X-ray contrast marker 66 under X-ray fluoroscopy. Therefore, the operator can easily determine the size of the therapeutic catheter to be inserted later.

Also, the linear shaft 30 of the guide extension catheter 10 and the dilator linear shaft 70 of the dilator 50 may be partially or wholly different in color. As a result, it becomes easy to distinguish between the two, and the convenience of the procedure can be improved.

Also, the linear shaft 30 or the dilator linear shaft 70 may be coated with a lubricant such as silicon to prevent the shafts from entangling with each other.

This application is based on Japanese Patent Application No. 2021-7432 filed on January 20, 2021, and the disclosure contents thereof are incorporated by reference.

10 guide extension catheter (catheter)
20 distal tube 21 tubular portion 22 semi-tubular portion 23 inner layer 24 reinforcing layer 25 intermediate layer 26 outer layer 27 distal marker 28 proximal marker 29 protrusion 30 linear shaft 50 dilator (catheter)
60 dilator tip tube (tip tube)
70 dilator linear shaft (linear shaft)
100 Guiding Catheter 101 Tip Opening

Claims

A catheter having an intermediate opening with a distal tube and a linear shaft extending proximally from the distal tube,
The tip tube has an outer layer, a middle layer disposed radially inward of the outer layer at least partially in the axial direction, and a reinforcing layer disposed radially inward of the middle layer,
A catheter having an intermediate opening, wherein said linear shaft is disposed between said outer layer and said intermediate layer and is spaced radially outwardly from said reinforcing layer.
The catheter according to claim 1, wherein the intermediate layer is a tubular collar member formed of a metal material, a member of a bridge structure that relays structures, or a member formed of a resin material.
The catheter having an intermediate opening according to claim 1 or 2, wherein the intermediate layer is formed to include at least a range in which the linear shaft is arranged in the circumferential direction of the tip tube.
The catheter having an intermediate opening according to claim 1 or 2, wherein the intermediate layer is formed all around in the circumferential direction of the tip tube.
The catheter having an intermediate opening according to any one of claims 1 to 4, characterized in that the middle layer and the outer layer have different colors.
The intermediate opening according to any one of claims 1 to 5, wherein the reinforcing layer is formed of a coil wound with at least one wire or a braid of a plurality of wires. Catheter with.
The catheter having an intermediate opening according to any one of claims 1 to 6, further comprising an inner layer disposed radially inside the reinforcing layer and forming an inner peripheral surface.
The catheter having an intermediate opening according to any one of claims 1 to 7, characterized in that the outer layer and the middle layer are made of a resin material.
The intermediate opening according to any one of claims 1 to 8, wherein the distance between the linear shaft and the reinforcing layer is 0.01 to 0.03 mm in the thickness direction of the tip tube. a catheter having a
In order to guide the therapeutic catheter to be inserted into the guiding catheter, the distal end of the therapeutic catheter is protruded from the distal opening of the guiding catheter, and advanced through the coronary artery to the periphery along the therapeutic catheter. 10. The catheter having an intermediate opening according to any one of claims 1 to 9, which is a guide extension catheter for arranging a treatment portion provided on the catheter to treat a lesion.