Extension catheter

Abstract

Provided is an extension catheter having excellent fixation strength of a linear member to a tubular member. The extension catheter is inserted into a catheter and can protrude from an opening on the distal side of the catheter, and has: a tubular member; and a linear member, the distal end of which is fixed to the tubular member, the tubular member having: an inner layer containing a fluororesin; and a proximal end portion located at a position closer to the proximal side than the proximal end of the inner layer, the linear member being fixed to the tubular member at least inside the proximal end portion.

Description

Technical Field

[0001] This invention relates to lengthening catheters. Background Technology

[0002] To date, percutaneous coronary intervention (PCI) has been used to treat ischemic heart diseases such as angina and myocardial infarction, employing endovascular devices such as stents and balloons to dilate narrowed sections of the coronary arteries and increase blood flow. In this procedure, sometimes after inserting and leaving the guide catheter at the entrance of the coronary artery, an extension catheter is inserted through the proximal opening of the guide catheter, with a portion of the extension catheter protruding from the distal opening into the coronary artery. Using such an extension catheter facilitates the delivery of endovascular devices to the affected area within the coronary artery. Various types of such extension catheters are known. For example, Patent Document 1 discloses an extension catheter comprising: a cylindrical portion; a first conical portion located closer to the position than the cylindrical portion; and a second conical portion located closer to the position than the first conical portion. The first conical portion has an outer surface and a first conical surface, and the second conical portion has an outer surface and a second conical surface. The angle θ1 formed by the first conical surface and the axial direction of the cylindrical portion is 90 to 145°, and the angle θ2 formed by the second conical surface and the axial direction is 120 to 175°.

[0003] Patent Document 1: International Publication No. 2020 / 162286 Summary of the Invention

[0004] In existing extension catheters such as those in Patent Document 1, the cylindrical component fixed to the distal end of the linear component can be moved by pushing or pulling the linear component in; however, depending on the method, this pushing and pulling is sometimes repeated within the body. The present invention addresses these issues and aims to provide an extension catheter with excellent fixation strength between the linear component and the cylindrical component.

[0005] The extension catheter involved in the implementation method that can solve the above-mentioned problems is as follows.

[0006] [1] An extension catheter, inserted into a catheter and capable of protruding from an opening on the distal side of the catheter, wherein it has:

[0007] Cylindrical components; and

[0008] The linear component, with its distal end fixed to the aforementioned cylindrical component,

[0009] The aforementioned cylindrical component has: an inner layer containing fluororesin; and a proximal end located closer to the position side than the proximal end of the inner layer.

[0010] The aforementioned linear component is fixed to the aforementioned cylindrical component at least inside the aforementioned proximal end.

[0011] Through the inventors' research, it has been found that if fluororesin is present in the portion near the linear component within the cylindrical component, the fixation strength of the linear component to the cylindrical component sometimes weakens. On the other hand, with the structure described above [1], fluororesin is less likely to be present in the portion near the linear component within the cylindrical component at the proximal end of the cylindrical component, which is located closer to the inner layer containing fluororesin than the inner layer, thereby increasing the fixation strength of the linear component to the cylindrical component. The extension catheter according to the embodiment is preferably any one of the following [2] to

[18] .

[0012] [2] According to the elongation catheter described in [1], wherein,

[0013] The aforementioned linear component has a portion inside the aforementioned proximal end that does not come into contact with fluoropolymer throughout its circumference.

[0014] [3] The elongation catheter as described in [1] or [2], wherein,

[0015] In the cross-section of the proximal end of the aforementioned cylindrical member in the radial direction, the region of the linear member located on the side closer to the central axis of the aforementioned cylindrical member and the region on the side farther from the central axis of the aforementioned cylindrical member are both regions.

[0016] [4] The elongation catheter described in any one of [1] to [3], wherein,

[0017] In the cross-section of the proximal end of the aforementioned cylindrical member in the radial direction, the proximal end has a portion extending radially along the aforementioned cylindrical member.

[0018] [5] The elongation catheter described in any one of [1] to [4], wherein,

[0019] In the cross-section of the proximal end of the aforementioned cylindrical component in the radial direction, the outer edge of the proximal end is elliptical, oblong, oval, or a combination thereof.

[0020] [6] The elongation catheter described in any one of [1] to [5], wherein,

[0021] The aforementioned cylindrical component has an outer layer located radially outward from the inner layer.

[0022] The proximal end of the outer layer is located at the proximal end of the cylindrical component, and the distal end of the outer layer is located at a position more distal than the proximal end of the inner layer.

[0023] [7] The elongation catheter described in any one of [1] to [6], wherein,

[0024] The cylindrical component has a first resin attached to the linear component, the first resin extending at least between the proximal end and the distal end of the linear component.

[0025] [8] The elongation catheter described in any one of [1] to [7], wherein,

[0026] The aforementioned linear component has a tapered portion.

[0027] [9] According to the elongation catheter described in [8], wherein,

[0028] The proximal end of the tapered portion of the linear component is located closer to the proximal end of the cylindrical component, and the distal end of the tapered portion of the linear component is located further to the distal end of the proximal end of the inner layer.

[0029]

[10] The elongation catheter described in any one of [1] to [9], wherein,

[0030] The distal end of the aforementioned linear component is located on the distal side compared to the proximal end of the aforementioned inner layer.

[0031]

[11] The elongation catheter described in any one of [1] to [6], [8], wherein,

[0032] The distal end of the aforementioned linear component is located closer to the position than the proximal end of the aforementioned inner layer.

[0033]

[12] The elongation catheter described in any one of [1] to

[11] , wherein,

[0034] The aforementioned cylindrical component has a braided tube.

[0035] The distal end of the aforementioned linear component is located on the distal side compared to the proximal end of the aforementioned braided tube.

[0036]

[13] The elongation catheter described in any one of [1] to

[11] , wherein,

[0037] The aforementioned cylindrical component has a braided tube.

[0038] The distal end of the aforementioned linear component is located closer to the side of the braid than the proximal end of the aforementioned braided tube.

[0039]

[14] The elongation catheter described in any one of [1] to

[13] , wherein,

[0040] The aforementioned cylindrical component has: a cylindrical portion; and a tapered portion located closer to the side than the aforementioned cylindrical portion.

[0041]

[15] The elongation catheter described in any one of [7]~

[10] ,

[12] ~

[14] , wherein,

[0042] The first resin mentioned above is a thermoplastic resin.

[0043]

[16] The elongation catheter described in any one of [1] to

[15] , wherein,

[0044] The aforementioned cylindrical component also has:

[0045] Braided tubing; and

[0046] At least one X-ray impermeable ring is configured such that the proximal end, distal end, or both ends of the braided tube are located inside.

[0047]

[17] The elongation catheter described in any one of [1] to

[16] , wherein,

[0048] The aforementioned linear component is a solid linear component without an internal cavity.

[0049]

[18] The elongation catheter described in any one of

[14] to

[17] , wherein,

[0050] In the radial direction of the cylindrical component, the proximal end of the tapered surface of the tapered portion is closer to the linear component than the distal end of the tapered surface.

[0051] According to the present invention, it is possible to provide an extension conduit with excellent fixing strength from a linear component to a cylindrical component. Attached Figure Description

[0052] Figure 1 This is a side view of the extension catheter involved in the embodiment.

[0053] Figure 2 It is Figure 1 A side view of the extension catheter being inserted into the guide catheter and a portion of it protruding from the distal opening.

[0054] Figure 3 yes Figure 1 A cross-sectional view of the tapered portion of the extended catheter and its vicinity along the axial direction.

[0055] Figure 4 yes Figure 1 IV-IV sectional view of the proximal end of the tubular component of the extended catheter.

[0056] Figure 5 yes Figure 1 A cross-sectional view of the proximal end of a modified example of the tubular component of an extended conduit, taken at section IV-IV.

[0057] Figure 6 yes Figure 1 Sectional view VI-VI of the tubular component of the extended conduit.

[0058] Figure 7 It means in Figure 1 A cross-sectional view VI-VI shows an example of fluoropolymer present near the linear component in the tubular part of an extended conduit.

[0059] Figure 8 It is inserted into the bent guiding catheter. Figure 1 Side view of the extended catheter.

[0060] Figure 9 yes Figure 1 A side view of the conical portion of the extended catheter and its vicinity.

[0061] Figure 10 yes Figure 1 A side view of a modified example of the linear component of the extended conduit.

[0062] Figure 11 It has an X-ray impermeable ring. Figure 1 Side view of the extended catheter. Detailed Implementation

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

[0064] The extension catheter according to the embodiment is inserted into a catheter and can protrude from an opening on the distal side of the catheter. It includes a cylindrical member and a linear member, with the distal end fixed to the cylindrical member. The cylindrical member has an inner layer containing fluororesin and a proximal end located closer to the distal end of the inner layer. The linear member is fixed to the cylindrical member at least inside the proximal end. Through the inventors' research, it has been found that if fluororesin is present in the portion near the linear member within the cylindrical member, the fixation strength of the linear member to the cylindrical member may sometimes be weakened. On the other hand, with the above structure, fluororesin is less likely to be present in the portion near the linear member within the cylindrical member at the proximal end of the cylindrical member located closer to the distal end than the inner layer containing fluororesin, thus improving the fixation strength of the linear member to the cylindrical member.

[0065] The following is for reference Figures 1-11 The extension catheter involved in the implementation method will be described. Figure 1 This is a side view of the extension catheter involved in the embodiment. Figure 2 It is Figure 1 A side view of the extension catheter being inserted into the guide catheter and a portion of it protruding from the distal opening. Figure 3 yes Figure 1 A cross-sectional view of the tapered portion of the extended catheter and its vicinity along the axial direction. Figure 4 yes Figure 1 IV-IV sectional view of the proximal end of the tubular component of the extended catheter. Figure 5 yes Figure 1 A cross-sectional view of the proximal end of a modified example of the tubular component of an extended conduit, taken at section IV-IV. Figure 6 yes Figure 1 Sectional view VI-VI of the tubular component of the extended conduit. Figure 7 It means in Figure 1 A cross-sectional view VI-VI shows an example of fluoropolymer present near the linear component in the tubular part of an extended conduit. Figure 8 It is inserted into the bent guiding catheter. Figure 1 Side view of the extended catheter. Figure 9 yes Figure 1 A side view of the conical portion of the extended catheter and its vicinity. Figure 10 yes Figure 1 A side view of a modified example of the linear component of the extended conduit. Figure 11 It has an X-ray impermeable ring. Figure 1 Side view of the extended catheter.

[0066] like Figure 1 As shown, the extension catheter 91 according to the embodiment has: a cylindrical component 1; and a linear component 2, with the distal end 2B fixed to the cylindrical component 1. Thus, the operator can push the cylindrical component 1 distally or pull it proximally via the linear component 2.

[0067] like Figure 2As shown, an extension catheter 91 is inserted into catheter 99 and can protrude from the distal opening 99Pb of catheter 99. For example, after inserting the distal end of catheter 99 into the entrance of the coronary artery and leaving it in place, extension catheter 91 is inserted into catheter 99 from the proximal opening 99Pa, and a portion of extension catheter 91 protrudes from the distal opening 99Pb of catheter 99 to be inserted into the coronary artery. This allows endovascular therapeutic devices to be delivered to the affected area within the coronary artery via catheter 99 and extension catheter 91. Examples of endovascular therapeutic devices include balloons and stents. Preferably, catheter 99 is a so-called guiding catheter. A therapeutic catheter, such as a balloon catheter or stent delivery catheter, is inserted into the lumen of the guiding catheter. The therapeutic catheter is preferably inserted into the coronary artery, but it can also be inserted into other arteries, veins, pancreatic ducts, bile ducts, urethra, bronchi, etc. Preferably, catheter 99 does not have through holes or grooves penetrating the outer and inner surfaces. Therefore, it is easy to insert the extension catheter 91 from the proximal opening 99Pa of the catheter 99 and allow a portion to protrude from the distal opening 99Pb.

[0068] like Figure 3 As shown, the cylindrical member 1 has: an inner layer 10L containing fluororesin; and a proximal end 1A located closer to the position than the proximal end 10La of the inner layer 10L. The linear member 2 is fixed to the cylindrical member 1 at least inside the proximal end 1A. In the proximal end 1A of the cylindrical member 1, located closer to the position than the fluororesin-containing inner layer 10L, fluororesin is less likely to be present in the portion near the linear member 2, thus increasing the fixation strength of the linear member 2 to the cylindrical member 1.

[0069] By containing a fluoropolymer in the inner layer 10L, the chemical resistance, non-stickiness, and low friction of the inner surface of the cylindrical component 1 are improved. The fluoropolymer preferably includes polytetrafluoroethylene, ethylene tetrafluoroethylene, fluorinated ethylene propylene, or combinations thereof.

[0070] Preferably, the linear component 2 has a portion inside the proximal end 1A that does not come into contact with the fluororesin throughout its circumference. Figure 4 In this process, a first resin R1 that does not contain fluorinated resin is attached to the entire circumference of the linear component 2. This improves the fixing strength of the linear component 2 at the proximal end 1A. Furthermore, it is preferable that the proximal end 1A does not contain fluorinated resin, but for example, a portion of the fluorinated resin dissolved from the portion other than the proximal end 1A may be slightly present within the proximal end 1A.

[0071] like Figure 4As shown, preferably in the cross-section of the proximal end 1A on the radial direction 1D of the cylindrical member 1, the region 1Af of the linear member 2 located on the side closer to the central axis 1C of the cylindrical member 1 is the region 1Af farther from the central axis 1C of the cylindrical member 1. Therefore, when operating the linear member 2, the portion of the linear member 2 located within the proximal end 1A is less likely to be exposed from the region 1A closer to the central axis 1C.

[0072] like Figure 4 As shown, preferably in the cross-section of the proximal end 1A in the radial direction 1D of the cylindrical member 1, the proximal end 1A has a portion extending along the radial direction 1D of the cylindrical member 1. Thus, when operating the linear member 2, the portion of the linear member 2 located within the proximal end 1A is less likely to be exposed from the proximal end 1A.

[0073] Preferably, in the cross-section of the proximal end 1A on the radial 1D of the cylindrical member 1, the outer edge of the proximal end 1A is elliptical, oblong, oval, or a combination thereof. Figure 4 The outer edge of the proximal end 1A has a combined shape of two ellipses, but it can also be like... Figure 5 The shape shown is an ellipse. As an oblong shape, it can be exemplified by a shape that extends from a portion of a circle, such as a pair of arcs with opposite spacing connected by a pair of parallel lines.

[0074] like Figure 3 , Figure 4 As shown, the preferred cylindrical component 1 has a first resin R1 attached to the linear component 2. The first resin R1 can easily bond with other resins, thereby improving the fixing strength of the linear component 2.

[0075] The first resin R1 is preferably a thermoplastic resin, more preferably a thermoplastic elastomer. This allows the first resin R1 to easily adhere to the linear component 2 and other resins during heating in the manufacturing process. The first resin R1 preferably comprises a polyamide resin, a polyurethane resin, a modified polyolefin resin, or a combination thereof, more preferably a polyamide resin, a polyurethane resin, or a combination thereof. The resin may also include an elastomer with rubber-like elasticity. For example, a polyamide resin may include a polyamide elastomer, and a polyurethane resin may include a polyurethane elastomer. Preferably, the first resin R1 does not contain a fluoropolymer.

[0076] like Figure 3As shown, preferably, the first resin R1 extends at least between the proximal end 1A and the distal end 2b of the linear member 2. This increases the fixing strength of the linear member 2 to the cylindrical member 1 via the first resin R1. Preferably, the distal end of the first resin R1 is located distally from the distal end 2b of the linear member 2. More preferably, the distal end of the first resin R1 is located in the axial direction 1X of the cylindrical member 1 closer to the distal end than a point 50 mm further distally separated from the distal end 2b of the linear member 2. This reduces the outer diameter of the cylindrical portion 10.

[0077] like Figure 3 As shown, the preferred cylindrical component 1 has an outer layer 10M located radially 1D outward from the inner layer 10L. Because the cylindrical component 1 has an outer layer 10M, the guidewire is less likely to penetrate the cylindrical component 1, for example, when inserted into the inner cavity of the cylindrical component 1.

[0078] The outer layer 10M preferably comprises polyamide resin, polyester resin, polyurethane resin, polyolefin resin, vinyl chloride resin, silicone resin, natural rubber, or combinations thereof, more preferably polyamide resin, polyurethane resin, or combinations thereof. The resin may also include an elastomer with rubber-like elasticity. The polyamide resin preferably comprises nylon 12, polyether block amide copolymer, or combinations thereof. Preferably, the outer layer 10M does not contain fluoropolymers.

[0079] The outer 10M layer may also have multiple layers stacked radially. Radially adjacent layers may contain different types of resin or the same type of resin.

[0080] Preferably, the outer layer 10M has a hydrophilic polymer on its outer surface. This facilitates insertion of the tubular component 1 into the guiding catheter or blood vessel. The hydrophilic polymer preferably includes poly(2-hydroxyethyl methacrylate), polyacrylamide, polyvinylpyrrolidone, maleic anhydride copolymer, or combinations thereof. The maleic anhydride copolymer is preferably a methyl vinyl ether maleic anhydride copolymer.

[0081] like Figure 1 , Figure 3 As shown, preferably, the proximal end 10Ma of the outer layer 10M is located at the proximal end 1A of the cylindrical member 1, and the distal end 10Mb of the outer layer 10M is located at a position more distal than the proximal end 10La of the inner layer 10L. This allows the first resin R1 to be applied to the outer layer 10M throughout the proximal end 1A and at a position more distal than the proximal end 1A, thereby increasing the fixation strength of the linear member 2 to the cylindrical member 1 via the first resin R1. Preferably, the distal end 10Mb of the outer layer 10M is located at a position more distal than the distal end 2b of the linear member 2. This also increases the fixation strength of the linear member 2 to the cylindrical member 1.

[0082] like Figure 3As shown, the cylindrical component 1 may also have an intermediate layer 10N, which is located radially 1D further outward than the inner layer 10L and further inward than the outer layer 10M. Alternatively, although not shown, the cylindrical component 1 may also have an intermediate layer 10N located further outward than the inner layer 10L without an outer layer 10M. The intermediate layer 10N preferably comprises a polyamide resin, polyester resin, polyurethane resin, polyolefin resin, vinyl chloride resin, silicone resin, natural rubber, or a combination thereof, more preferably a polyamide resin, polyurethane resin, or a combination thereof. The resin may also comprise an elastomer with rubber elasticity. The polyamide resin preferably comprises nylon 12, polyether block amide copolymer, or a combination thereof. Preferably, the intermediate layer 10N does not contain a fluoropolymer. Preferably, the intermediate layer 10N comprises a resin different from the resin contained in the outer layer 10M. When the intermediate layer 10N has an exposed portion on its outer side, it is preferable that the exposed portion of the intermediate layer 10N on its outer side has a hydrophilic polymer. For information on hydrophilic polymers, please refer to the description of the hydrophilic polymer on the outer surface of the outer 10M layer.

[0083] like Figure 3 As shown, preferably, the proximal end 10Na of the intermediate layer 10N is located at the same position as the proximal end 10La of the inner layer 10L in the axial direction 1X of the cylindrical member 1, or at a position closer to the proximal end 10La of the inner layer 10L. Furthermore, as... Figure 1 , Figure 3 As shown, preferably, the distal end 10Nb of the intermediate layer 10N is located more distally than the proximal end 10La of the inner layer 10L. Therefore, the portion near the linear component 2 in the cylindrical component 1 is less likely to contain fluoropolymer. For example... Figure 1 As shown, the distal end 10Mb of the outer layer 10M is preferably located closer to the distal end 10Nb of the intermediate layer 10N. This reduces the outer diameter of the portion of the cylindrical component 1 that is further distal than the outer layer 10M.

[0084] like Figure 6 As shown, preferably, in the portion distal to the proximal end 1A, the first resin R1 attached to the linear member 2 does not contact the inner layer 10L containing fluorinated resin. This increases the fixing strength of the linear member 2 to the cylindrical member 1 via the first resin R1. However, for example, when using a heat-shrink tube to heat and bury the linear member 2 with the first resin R1 within the intermediate layer 10N to fix the linear member 2 to the cylindrical member 1, such as... Figure 7 As shown, there is sometimes a portion where the first resin R1 contacts the inner layer 10L. At this contact portion, the fixing strength of the linear component 2 via the first resin R1 weakens, but fluoropolymer is not readily present near the linear component 2 in the proximal end 1A of the extension conduit 91, thus the linear component 2 can be firmly fixed in the proximal end 1A.

[0085] like Figure 3 As shown, the distal end 2b of the preferred linear member 2 is located more distally than the proximal end 10La of the inner layer 10L. This elongates the linear member 2 towards the fixed portion of the cylindrical member 1, thereby increasing the fixing strength of the linear member 2 towards the cylindrical member 1.

[0086] Although not shown in the figure, the distal end 2b of the linear member 2 can also be located closer to the side than the proximal end 10La of the inner layer 10L. This can improve the flexibility of the cylindrical member 1.

[0087] like Figure 6 As shown, preferably in the portion distal to the proximal end 1A, the linear member 2 is disposed radially 1D in the cylindrical member 1 between the inner layer 10L and the outer layer 10M, or within the outer layer 10M. This allows the linear member 2 to be easily and securely fixed to the cylindrical member 1. Furthermore, it is preferable that the first resin R1 is attached to the outer surface of the linear member 2 in the portion where the linear member 2 is fixed to the cylindrical member 1.

[0088] Preferably, the inner layer 10L, the middle layer 10N, and the outer layer 10M extend from the cylindrical portion 10 (described later) along the axial direction 10X to the tapered portion 11. This allows for easy and smooth bending in the order from the cylindrical portion 10 to the tapered portion 11.

[0089] like Figure 1 As shown, the preferred cylindrical member 1 has a cylindrical portion 10 and a tapered portion 11 located closer to the cylindrical portion 10 than the cylindrical portion 10. The tapered portion 11 is shorter in length in the radial direction 1D than the cylindrical portion 10 and has an opening 11P communicating with the inner cavity of the cylindrical member 1 and facing radial direction 1D. The tapered portion 11 has at least one tapered surface inclined relative to the axial direction 10X of the cylindrical portion 10, thus, for example, as Figure 8 As shown, an intravascular treatment device can be easily inserted into the lumen of the cylindrical component 1 through the opening 11P of the conical portion 11 of the curved portion 1 that is inserted into the body. When inserting the intravascular treatment device into the opening 11P, a treatment catheter such as a balloon catheter or a stent delivery catheter can be used.

[0090] like Figure 9 As shown, the tapered portion 11 of the preferred cylindrical component 1 has a plurality of tapered surfaces. Preferably, the plurality of tapered surfaces includes a first tapered surface S1 located on the farthest side. The angle θ1 formed by the first tapered surface S1 and the axial direction 10X of the cylindrical portion 10 is preferably 20° or more, more preferably 30° or more. Thus, as... Figure 3As shown, the thin-walled portion near the distal end 11b of the conical portion 11 can be reduced, making it less likely for endovascular therapeutic instruments to snag near the distal end 11b of the conical portion 11. On the other hand, the angle θ1 is preferably 89° or less, more preferably 85° or less. This increases the opening area of ​​the opening 11P, which is located at least inside the first conical surface S1. Furthermore, the conical portion 11 of the cylindrical member 1 may have only one conical surface.

[0091] like Figure 9 As shown, the preferred conical portion 11 preferably includes a first conical surface S1 and a second conical surface S2 located closer to the first conical surface S1. Preferably, the angle formed by the second conical surface S2 and the axial direction 10X of the cylindrical portion 10 is smaller than the angle θ1 formed by the first conical surface S1 and the axial direction 10X of the cylindrical portion 10. This increases the opening area of ​​the opening 11P. The angle formed by the second conical surface S2 and the axial direction 10X of the cylindrical portion 10 is preferably less than 85°, more preferably less than 80°. This further increases the opening area of ​​the opening 11P. On the other hand, this angle is preferably 10° or more, more preferably 20° or more. This prevents the endovascular treatment device from easily wobbling when inserted into the opening 11P.

[0092] like Figure 9 As shown, the preferred conical portion 11 preferably includes a plurality of conical surfaces: a first conical surface S1; a second conical surface S2 located closer to the position than the first conical surface S1; and a third conical surface S3 located closer to the position than the second conical surface S2. Preferably, the angle formed by the third conical surface S3 and the axial direction 10X of the cylindrical portion 10 is smaller than the angle formed by the second conical surface S2 and the axial direction 10X of the cylindrical portion 10. This increases the area of ​​the opening 11P. The angle formed by the third conical surface S3 and the axial direction 10X of the cylindrical portion 10 is preferably 5° or less, more preferably 2° or less, and most preferably 0°. Furthermore, the third conical surface S3 preferably includes the proximal end 11a of the conical portion 11. Additionally, the first conical surface S1 is preferably adjacent to the second conical surface S2. Preferably, the second conical surface S2 is adjacent to the third conical surface S3. The tapered surfaces of the tapered portion 11 can be formed by a first tapered surface S1 and a second tapered surface S2, or by a first tapered surface S1 and a third tapered surface S3, or by a second tapered surface S2 and a third tapered surface S3. The tapered surfaces of the tapered portion 11 of the cylindrical member 1 can be formed, for example, by cutting off a portion of the proximal end of the cylindrical body using a cutting tool such as a knife to create a slit at the proximal end.

[0093] like Figure 9As shown, in a field of view where the cylindrical component 1 is oriented towards the conical surface of the conical portion 11 in a linear direction, the first conical surface S1, the second conical surface S2, and the third conical surface S3 are preferably straight or curved, more preferably straight. By making the conical surfaces straight, manufacturing efficiency is improved. Furthermore, when the first conical surface S1 is curved in this field of view, the angle θ1 formed by the first conical surface S1 and the axial direction 10X of the cylindrical portion 10 is the angle formed by the line connecting the proximal end S1a and the distal end S1b of the first conical surface S1 and the axial direction 10X. Similarly, when the second conical surface S2 and the third conical surface S3 are curved in this field of view, the angle formed by each surface and the axial direction 10X of the cylindrical portion 10 is the angle formed by the line connecting the proximal end and the distal end of each surface and the axial direction 10X.

[0094] Preferably, the second conical surface S2 is the conical surface with the largest area among a plurality of conical surfaces that are inclined at an angle greater than 5° and less than 89° relative to the axial direction 10X of the cylindrical portion 10. Figure 9 In this configuration, the first conical surface S1 and the second conical surface S2 are inclined at an angle greater than 5° and less than 89° relative to the axial direction 10X of the cylindrical portion 10, with the second conical surface S2 having the largest area. This makes it easier to achieve the aforementioned effect of the inclination of the second conical surface S2.

[0095] Preferably, the second conical surface S2 is the longest conical surface in the radial direction 1D of the cylindrical component 1 among the multiple conical surfaces. Figure 9 Among the first conical surface S1, the second conical surface S2, and the third conical surface S3, the second conical surface S2 has the longest radial length 1D. Therefore, it is easier to obtain the tilting effect of the second conical surface S2 mentioned above.

[0096] like Figure 9 As shown, preferably, in the radial direction 1D of the cylindrical member 1, the proximal end of the conical surface is closer to the linear member 2 than the distal end of the conical surface. Specifically, preferably, the proximal end S1a of the first conical surface S1 is closer to the linear member 2 than the distal end S1b of the first conical surface S1. By tilting the first conical surface S1 in this way, it is easy to insert the endovascular treatment device through the opening 11P located at least inside the first conical surface S1. Furthermore, preferably, in the radial direction 1D of the cylindrical member 1, the proximal end of the second conical surface S2 is closer to the linear member 2 than the distal end of the second conical surface S2. The proximal end of the third conical surface S3 may also be closer to the linear member 2 than the distal end of the third conical surface S3, but preferably the third conical surface S3 is parallel to the linear member 2.

[0097] like Figure 9As shown, in a view where the conical surface of the cylindrical member 1 facing the conical portion 11 is linear, the proximal end 1A of the cylindrical member 1 may also have an inwardly protruding portion in the radial direction 1D of the cylindrical member 1. Preferably, this protruding portion contains the first resin R1. Thus, during operation of the linear member 2, the linear member 2 is less likely to detach from the cylindrical member 1. Furthermore, although not shown, in this view, the proximal end 1A of the cylindrical member 1 may not have an inwardly protruding portion in the radial direction 1D of the cylindrical member 1.

[0098] Preferably, the cylindrical component 1 does not have through holes, grooves, or the like penetrating the outer and inner surfaces of the cylindrical portion 10, the conical portion 11, or both. This prevents the endovascular treatment device from being snagged inside the cylindrical component 1 during delivery. Furthermore, it is preferable that the cylindrical component 1 does not have non-penetrating grooves on the outer surfaces of the cylindrical portion 10, the conical portion 11, or both. This reduces the likelihood of damage to the cylindrical component 1 during the insertion of guidewires, endovascular treatment devices, etc. Alternatively, the cylindrical component 1 may have a coil in the cylindrical portion 10, the conical portion 11, or both. By having a coil or a braided tube 12 (described later), or even both a coil and a braided tube 12, flexibility is maintained and the cylindrical component 1 is less likely to be flattened radially 1D. On the other hand, by not having a coil or a braided tube 12, the radial length 1D of the cylindrical component 1 can be reduced.

[0099] Preferably, the cylindrical component 1 has a braided tube 12. Specifically, it is preferable that the cylindrical component 1 has a braided tube 12 at least in the cylindrical portion 10. The braided tube 12 can strengthen the cylindrical portion 10, for example, making it less likely for the guide wire to penetrate the cylindrical portion 10 when it is inserted into the inner cavity of the cylindrical portion 10. Furthermore, it is more preferable that the cylindrical component 1 has a braided tube 12 in the cylindrical portion 10 but not in the tapered portion 11. This allows the tapered portion 11 to bend more easily. Additionally, it is preferable that the distal end 12b of the braided tube 12 is located in a region closer to the distal end of the cylindrical portion 10 and within 5 mm of the distal end of the cylindrical portion 10. This allows reinforcement to be provided near the distal end of the cylindrical portion 10.

[0100] like Figure 9 As shown, preferably, the proximal end 12a of the braided tube 12 is located further distally than the distal end S1b of the first conical surface S1. This allows the first conical surface S1 and its vicinity to bend easily. More preferably, the proximal end 12a of the braided tube 12 is located further distally than the distal end 11b of the conical portion 11. This allows the conical portion 11 to bend easily.

[0101] The braided tube 12 preferably has a mesh structure formed by interlacing multiple wires. Each wire can be a single wire or a stranded wire. As the wire, the braided tube 12 preferably has metal wire, fiber, or a combination thereof, more preferably metal wire. The metal wire preferably includes stainless steel, titanium, nickel-titanium alloy, nickel-chromium alloy, cobalt-chromium alloy, tungsten alloy, or a combination thereof, more preferably stainless steel. The metal wire may also contain X-ray impermeable materials described later. The fiber preferably includes polyaramid fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, PBO fiber, carbon fiber, or a combination thereof. The fiber can be a monofilament or a multifilament.

[0102] Preferably, the braided tube 12 is disposed radially 1D in the cylindrical member 1 between the inner layer 10L and the intermediate layer 10N, or within the intermediate layer 10N. This prevents the braided tube 12 from being exposed into the inner cavity of the cylindrical portion 10.

[0103] like Figure 3 As shown, the distal end 2b of the preferred linear member 2 is located further distally than the proximal end 12a of the braided tube 12. This elongates the linear member 2 towards the fixing portion of the tubular member 1, thereby increasing the fixing strength of the linear member 2 towards the tubular member 1. Furthermore, when the tubular member 1 is inserted into the curved portion of the body, it can be easily and smoothly bent in the order of the braided tube 12 and the portion closer to the fixing portion of the braided tube 12.

[0104] Although not shown in the figure, the distal end 2b of the linear member 2 can also be located closer to the position side than the proximal end 12a of the braided tube 12. This allows for a reduction in the outer diameter of the cylindrical portion 10 where the braided tube 12 is located. In this case, the distal end 2b of the linear member 2 can be located distally to the position side of the distal end S1b of the first conical surface S1, or it can be closer to the position side of the distal end S1b of the first conical surface S1. Similarly, the distal end 2b of the linear member 2 can be located distally to the position side of the distal end 11b of the conical portion 11, or it can be closer to the position side of the distal end 11b of the conical portion 11.

[0105] like Figure 3 As shown, the preferred linear component 2 has a tapered portion 2T. By having a tapered portion 2T that tapers towards the distal end 2b, the outer diameter of the distal end 2b of the linear component 2 and the adjacent cylindrical component 1 can be easily reduced. Consequently, this portion can bend smoothly when inserted into a curved portion within the body. Preferably, the tapered portion 2T includes or is adjacent to the distal end 2b of the linear component 2.

[0106] like Figure 3As shown, the tapered portion 2T of the preferred linear member 2 preferably has a tapered surface 2S. The tapered surface 2S preferably includes or is adjacent to the distal end 2b of the linear member 2. The angle between the tapered surface 2S and the axial direction 2X of the linear member 2 is preferably 1° or more and 45° or less, more preferably 2° or more and 30° or less. Figure 3 As shown, the tapered surface 2S of the tapered portion 2T of the linear member 2 can face outward in the radial direction 1D of the cylindrical member 1, although not shown, it can also face inward in the radial direction 1D. The outward side in the radial direction 1D of the cylindrical member 1 refers to the side in the radial direction 1D furthest from the central axis 1C of the cylindrical member 1, and the inward side in the radial direction 1D of the cylindrical member 1 refers to the side in the radial direction 1D closest to the central axis 1C of the cylindrical member 1. Furthermore, the tapered portion 2T of the linear member 2 can also have: a tapered surface facing outward in the radial direction 1D of the cylindrical member 1; and a tapered surface facing inward in the radial direction 1D of the cylindrical member 1.

[0107] like Figure 10 As shown, the tapered portion 2T of the linear member 2 may also have multiple tapered surfaces. In this case, it is preferable that the multiple tapered surfaces include a distal tapered surface 2S1 located at the farthest position and a proximal tapered surface 2S2 located closer to the position than the distal tapered surface 2S1. The angles formed by the distal tapered surface 2S1 and the proximal tapered surface 2S2 with the axial direction 2X of the linear member 2 are preferably 1° or more and 45° or less, more preferably 2° or more and 30° or less. The angle formed by the distal tapered surface 2S1 with the axial direction 2X of the linear member 2 can be greater than the angle formed by the proximal tapered surface 2S2 with the axial direction 2X of the linear member 2, or it can be smaller than the angle formed by the proximal tapered surface 2S2 with the axial direction 2X of the linear member 2. In the axial direction 2X, the distal tapered surface 2S1 can be longer or shorter than the proximal tapered surface 2S2.

[0108] like Figure 3 As shown, the proximal end 2Ta of the tapered portion 2T of the preferred linear member 2 is located closer to the position than the proximal end 1a of the cylindrical member 1. This improves the flexibility of the portion of the cylindrical member 1 in which the linear member 2 is disposed.

[0109] Although not shown in the figure, it is preferable that the distal end 2Tb of the tapered portion 2T of the linear member 2 is located more distally than the proximal end 10La of the inner layer 10L. As a result, the flexibility of the portion of the cylindrical member 1 in which the linear member 2 is disposed is improved.

[0110] like Figure 3 , Figure 6As shown, the preferred linear component 2 is a solid linear component without an internal cavity. This reduces the thickness of the linear component 2. The linear component 2 only needs to be able to push the cylindrical portion 10 distally; its material is not particularly limited, but preferably includes stainless steel, titanium, nickel-titanium alloy, cobalt-chromium alloy, tungsten alloy, or combinations thereof, and more preferably stainless steel. The cross-sectional shape of the linear component 2 in the thickness direction is preferably square, rectangular, trapezoidal, circular, D-shaped, or elliptical, and more preferably rectangular. The cross-sectional shape of the linear component 2 in the thickness direction can vary depending on its axial position, and its size can also vary. For example, the linear component 2 may also have a portion that tapers towards the distal end, i.e., a tapered portion 2T.

[0111] like Figure 1 As shown, the preferred extension catheter 91 also has a handle component 3, which is fixed to the proximal end of the linear component 2. The operator can hold the handle component 3 to move the linear component 2 distally or proximally. The handle component 3 preferably comprises resin. The resin is preferably a polyolefin resin. Polyolefin resins preferably include polyethylene, polypropylene, or combinations thereof.

[0112] like Figure 11 As shown, the cylindrical component 1 may also further have a proximal end 12a, a distal end 12b, or at least one X-ray impermeable ring 13 configured as a braided tube 12 with both ends located inside. Figure 11 In this configuration, an X-ray impermeable ring 13 is disposed at the distal end 12b of the braided tube 12, serving as a marker near the distal end of the cylindrical portion 10 under X-ray fluoroscopy. Although not shown, if the X-ray impermeable ring 13 is disposed at the proximal end 12a of the braided tube 12, the X-ray impermeable ring 13 can serve as a marker near the distal end 11b of the conical portion 11 under X-ray fluoroscopy. Preferably, the X-ray impermeable ring 13 is disposed radially 1D in the cylindrical member 1 between the braided tube 12 and the intermediate layer 10N. This suppresses the unraveling of the end of the braided tube 12 and easily prevents the braided tube 12 from being exposed on the outer surface of the cylindrical member 1.

[0113] X-ray impermeable ring 13 is a ring containing an X-ray impermeable material, preferably composed of an X-ray impermeable material. The X-ray impermeable material preferably includes lead, barium, iodine, tungsten, gold, platinum, iridium, platinum-iridium alloy, stainless steel, titanium, cobalt-chromium alloy, palladium, tantalum, or combinations thereof.

[0114] Along the axial direction 10X of the cylindrical portion 10, the length from the proximal end of the cylindrical member 1 to the proximal end of the linear member 2 is preferably at least twice the length of the cylindrical member 1. This reduces friction when inserted into the catheter 99. This multiple can also be 10 times or less. The length of the extension catheter 91 is preferably 1000 mm or more and 2000 mm or less. The length of the cylindrical member 1 is preferably 150 mm or more and 500 mm or less. The outer diameter of the cylindrical member 1 is preferably 1.2 mm or more and 3 mm or less. The inner diameter of the cylindrical member 1 is preferably 1.0 mm or more and 2.2 mm or less.

[0115] This application claims a priority interest based on Japanese Patent Application No. 2024-032457, filed March 4, 2024. The entire contents of the description of Japanese Patent Application No. 2024-032457, filed March 4, 2024, are incorporated herein by reference.

[0116] Explanation of reference numerals in the attached figures

[0117] 1…Cylindrical component; 1A…Proximal end; 1An…Region on the side closest to the central axis; 1Af…Region on the side furthest from the central axis; 1C…Central axis; 1D…Radial; 1X…Axial; 2…Linear component; 2b…Distal end; 2B…Distal end; 2T…Conical portion; 2Ta…Proximal end; 2Tb…Distal end; 2S…Conical surface; 2S1…Distal conical surface; 2S2…Proximal conical surface; 2X…Axial; 3…Handle component; 10…Cylindrical portion; 10L…Inner layer; 10La…Proximal end; 10N…Intermediate layer; 10Na…Proximal end; 1 0Nb…distal end; 10M…outer layer; 10Ma…proximal end; 10Mb…distal end; 10X…axial direction; 11…conical portion; 11a…proximal end; 11b…distal end; 11P…opening; 12…braided tube; 12a…proximal end; 12b…distal end; 13…X-ray impermeable ring; 91…extending conduit; 99…conduit; 99Pa…opening on the proximal side; 99Pb…opening on the distal side; R1…first resin; S1, S2, S3…first conical surface, second conical surface, third conical surface; S1a…proximal end; S1b…distal end.

Claims

1. An extension catheter, inserted into a conduit and capable of protruding from an opening on the distal side of said conduit, characterized in that, have: Cylindrical components; and The linear component has its distal end fixed to the cylindrical component. The cylindrical component has: an inner layer containing fluororesin; and a proximal end located closer to the position side than the proximal end of the inner layer. The linear component is fixed to the cylindrical component at least inside the proximal end.

2. The extension catheter according to claim 1, characterized in that, The linear component has a portion inside the proximal end that does not come into contact with the fluoropolymer throughout its circumference.

3. The extension catheter according to claim 1 or 2, characterized in that, In the cross-section of the proximal end of the cylindrical member in the radial direction, the linear member is located in the region on the side closer to the central axis of the cylindrical member and the region on the side farther from the central axis of the cylindrical member, respectively.

4. The extension catheter according to claim 1 or 2, characterized in that, In a cross-section of the proximal end of the cylindrical member in the radial direction, the proximal end has a portion extending radially along the cylindrical member.

5. The extension catheter according to claim 1 or 2, characterized in that, In a cross-section of the proximal end in the radial direction of the cylindrical component, the outer edge of the proximal end is elliptical, oblong, oval, or a combination thereof.

6. The extension catheter according to claim 1 or 2, characterized in that, The cylindrical component has an outer layer located radially outward from the inner layer. The proximal end of the outer layer is located at the proximal end of the cylindrical component, and the distal end of the outer layer is located at a position more distal than the proximal end of the inner layer.

7. The extension catheter according to claim 1 or 2, characterized in that, The cylindrical component has a first resin attached to the linear component, the first resin extending at least between the proximal end and the distal end of the linear component.

8. The extension catheter according to claim 1 or 2, characterized in that, The linear component has a tapered portion.

9. The extension catheter according to claim 8, characterized in that, The proximal end of the tapered portion of the linear component is located closer to the proximal end of the cylindrical component, and the distal end of the tapered portion of the linear component is located further to the distal end of the proximal end of the inner layer.

10. The extension catheter according to claim 1 or 2, characterized in that, The distal end of the linear component is located on the distal side compared to the proximal end of the inner layer.

11. The extension catheter according to claim 1 or 2, characterized in that, The distal end of the linear component is located closer to the position than the proximal end of the inner layer.

12. The extension catheter according to claim 1 or 2, characterized in that, The cylindrical component has a braided tube. The distal end of the linear component is located further distally than the proximal end of the braided tube.

13. The extension catheter according to claim 1 or 2, characterized in that, The cylindrical component has a braided tube. The distal end of the linear component is located closer to the side of the braid than the proximal end of the braided tube.

14. The extension catheter according to claim 1 or 2, characterized in that, The cylindrical component has: a cylindrical portion; and a tapered portion located closer to the side than the cylindrical portion.

15. The extension catheter according to claim 7, characterized in that, The first resin is a thermoplastic resin.

16. The extension catheter according to claim 1 or 2, characterized in that, The cylindrical component also has: Braided tubing; and At least one X-ray-impermeable ring is configured such that the proximal end, distal end, or both ends of the braided tube are located inside.

17. The extension catheter according to claim 1 or 2, characterized in that, The linear component is a solid linear component without an internal cavity.

18. The extension catheter according to claim 14, characterized in that, In the radial direction of the cylindrical component, the proximal end of the tapered surface of the tapered portion is closer to the linear component than the distal end of the tapered surface.

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