Extension catheter

Abstract

Provided is an elongated catheter in which a curved portion inserted into a body is less likely to be deformed into a skew shape. The elongated 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 wire member whose distal end is fixed to the tubular member. The tubular member has a tubular portion and a tapered portion located on the proximal side of the tubular portion. The tubular member has a braided tube at least in the tubular portion. An opening of the proximal side of the braided tube has a surface inclined in the radial direction of the braided tube. The proximal end of the surface of the opening is closer to the wire member than the distal end of the surface of the opening.

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 extension catheters are known. For example, Patent Document 1 discloses an extension catheter comprising: a cylindrical portion; a first tapered portion located closer to the position than the cylindrical portion; and a second tapered portion located closer to the position than the first tapered portion. The first tapered portion has an outer surface and a first tapered surface, and the second tapered portion has an outer surface and a second tapered surface. The angle θ1 between the first tapered surface and the axial direction of the cylindrical portion is 90~145°, and the angle θ2 between the second tapered surface and the axial direction is 120~175°. Furthermore, Patent Document 1 also discloses that the cylindrical portion has a braided reinforcing layer.

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

[0004] In existing extension catheters such as Patent Document 1, which have a braided reinforcing layer in the cylindrical portion, the inventors have learned through their research that when the cylindrical portion is inserted into a curved portion such as an artery in the body, the portion near the proximal end of the reinforcing layer sometimes deforms into a skewed shape. The present invention was made with regard to the above-mentioned problem in mind, and its object is to provide an extension catheter in which the cylindrical portion is less likely to deform into a skewed shape even when inserted into a curved portion in the body.

[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 a cylindrical portion and a tapered portion located closer to the position side than the cylindrical portion.

[0010] The aforementioned cylindrical component has a braided tube at least in the aforementioned cylindrical portion.

[0011] The opening of the proximal side of the braided tube, including the aforementioned braided tube, has an inclined surface.

[0012] In the radial direction of the braided tube, the proximal end of the opening containing the surface is closer to the linear member than the distal end of the opening containing the surface.

[0013] As described above, by having an opening containing a surface that is inclined in the radial direction such that the proximal end is closer to the linear member than the distal end, the tubular portion is less likely to deform into a skewed shape when the tubular portion is inserted into the body with the distal end of the opening containing the surface becoming the curved inner side. The preferred embodiment of the extension catheter is any one of the following [2] to

[12] .

[0014] [2] According to the elongation catheter described in [1], wherein,

[0015] The aforementioned tapered portion has a first tapered surface and satisfies the following equations (1) and (2).

[0016] θ1≤45° …(1)

[0017] θ2<45° …(2)

[0018] [In the formula, θ1 represents the angle between the opening surface of the braided tube and the first conical surface. θ2 represents the angle between the first conical surface and the axial direction of the cylindrical portion.]

[0019] [3] According to the elongation catheter described in [2], wherein,

[0020] The aforementioned tapered portion has multiple tapered surfaces, and the aforementioned first tapered surface is the tapered surface with the largest area among the multiple tapered surfaces that are inclined at an angle of more than 5° and less than 89° relative to the axial direction of the aforementioned cylindrical portion.

[0021] [4] The elongation catheter described in any one of [1] to [3], wherein,

[0022] The braided tube described above has a first wire, and the first wire has a first inclined portion that is axially inclined relative to the cylindrical portion.

[0023] In the field of view where the cylindrical component is oriented toward the tapered surface of the tapered portion as a line, the following equation (3) is satisfied.

[0024] θ3>θ4 …(3)

[0025] [In the formula, θ3 represents the angle between the surface containing the opening of the braided tube and the axial direction of the cylindrical portion. θ4 represents the angle between the first inclined portion and the axial direction of the cylindrical portion.]

[0026] [5] The elongation catheter described in any one of [1] to [3], wherein,

[0027] The braided tube described above has a first wire, and the first wire has a first inclined portion that is axially inclined relative to the cylindrical portion.

[0028] In the field of view where the cylindrical component is oriented toward the tapered surface of the tapered portion as a line, the following equation (4) is satisfied.

[0029] θ3<θ4 …(4)

[0030] [In the formula, θ3 represents the angle between the surface containing the opening of the braided tube and the axial direction of the cylindrical portion. θ4 represents the angle between the first inclined portion and the axial direction of the cylindrical portion.]

[0031] [6] The elongation catheter described in any one of [1] to [5], wherein,

[0032] The distal end of the aforementioned linear component is located on the distal side compared to the proximal end of the aforementioned braided tube.

[0033] [7] The elongation catheter described in any one of [1] to [5], wherein,

[0034] 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.

[0035] [8] The elongation catheter described in any one of [2] to [7], wherein,

[0036] In a field of view where the cylindrical component is oriented in a linear direction toward the first conical surface, the shortest distance from the distal end of the opening of the braided tube to the first conical surface is at least 0.5 times the radial length of the braided tube at the distal end of the opening of the braided tube.

[0037] [9] The elongation catheter described in any one of [2] to [8], wherein,

[0038] The proximal end of the braided tube is located on the distal side compared to the distal end of the first conical surface.

[0039]

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

[0040] The aforementioned cylindrical component also has at least one X-ray impermeable ring configured as the proximal end, distal end, or both ends of the aforementioned braided tube located inside.

[0041]

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

[10] , wherein,

[0042] The aforementioned linear component is a solid linear component without an internal cavity.

[0043]

[12] The elongation catheter described in any one of [2] to

[11] , wherein,

[0044] In the radial direction of the braided tube, the proximal end of the first tapered surface is closer to the linear component than the distal end of the first tapered surface.

[0045] According to the present invention, it is possible to provide an extension catheter in which the cylindrical portion does not easily deform into a skewed shape even when inserted into a curved portion of the body. Attached Figure Description

[0046] Figure 1 This is a side view of the extension catheter involved in the implementation method.

[0047] 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.

[0048] Figure 3 It is inserted into the curved guide catheter. Figure 1 Side view of the extended catheter.

[0049] Figure 4 yes Figure 1 A side view of the conical portion of the extended catheter and its vicinity.

[0050] Figure 5 It is configured in Figure 1 Side view of the braided tube inside the tubular portion of the extended conduit.

[0051] Figure 6 It is configured in Figure 1 A side view of a modified example of a braided tube inside the tubular portion of an extended conduit.

[0052] Figure 7 yes Figure 1 A cross-sectional view of the tapered portion of the extended catheter and its vicinity along the axial direction.

[0053] Figure 8 yes Figure 1 Sectional view of VIII-VIII.

[0054] Figure 9 It has an X-ray impermeable ring. Figure 1 Side view of the extended catheter. Detailed Implementation

[0055] 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.

[0056] The extension catheter involved in 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, the distal end of which is fixed to the cylindrical member. The cylindrical member has a cylindrical portion and a tapered portion located closer to the distal side than the cylindrical portion. The cylindrical member has a braided tube at least in the cylindrical portion. The opening containing surface of the proximal side of the braided tube is inclined. In the radial direction of the braided tube, the proximal end of the opening containing surface is closer to the linear member than the distal end of the opening containing surface. As described above, by having an opening containing surface that is inclined in the radial direction such that the proximal end is closer to the linear member than the distal end, when the cylindrical member is inserted into the body with the distal end of the opening containing surface becoming the curved inner side, the portion near the proximal end of the braided tube is less likely to deform into a skewed shape.

[0057] The following is for reference Figures 1-9 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 implementation method. 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 It is inserted into the curved guide catheter. Figure 1 Side view of the extended catheter. Figure 4 yes Figure 1 A side view of the conical portion of the extended catheter and its vicinity. Figure 5 It is configured in Figure 1 Side view of the braided tube inside the tubular portion of the extended conduit. Figure 6 It is configured in Figure 1 A side view of a modified example of a braided tube inside the tubular portion of an extended conduit. Figure 7 yes Figure 1 A cross-sectional view of the tapered portion of the extended catheter and its vicinity along the axial direction. Figure 8 yes Figure 1 Sectional view of VIII-VIII. Figure 9 It has an X-ray impermeable ring. Figure 1 Side view of the extended catheter.

[0058] 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.

[0059] like Figure 2 As 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.

[0060] like Figure 1 As shown, the 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 outward in the radial direction 1D. The tapered portion 11 has at least one tapered surface that is inclined relative to the axial direction 10X of the cylindrical portion 10, and thus, for example, as... Figure 3 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.

[0061] like Figure 1As shown, the cylindrical member 1 has a braided tube 12 at least in the cylindrical portion 10. The braided tube 12 can reinforce the cylindrical portion 10, for example, making it less likely for the guide wire to penetrate the cylindrical portion 10 when inserted into its inner cavity. Furthermore, it is more preferable that the cylindrical member 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 easily. Additionally, it is preferable that the distal end 12b of the braided tube 12 is located 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 up to the vicinity of the distal end of the cylindrical portion 10.

[0062] like Figure 4 , Figure 5 As shown, the opening 12Q, including the proximal side of the braided tube 12, has an inclined surface 12S. Specifically, the opening has a surface 12S that is inclined relative to the axial direction 10X of the cylindrical portion 10. Figure 4 As shown, in the radial direction 12D of the braided tube 12, the proximal end 12Sa of the opening containing the surface 12S is closer to the wire member 2 than the distal end 12Sb of the opening containing the surface 12S. Thus, for example... Figure 3 As shown, when the cylindrical portion 10 is inserted into the curved portion of the body with the distal end 12Sb of the opening containing the surface 12S as the curved inner side, the portion of the cylindrical portion 10 near the proximal end 12a of the braided tube 12 is less likely to deform into a skewed shape. Furthermore, the proximal opening 12Q of the braided tube 12 is the portion surrounding the proximal opening 12P facing the braided tube 12. The inclined opening containing the surface 12S can be formed, for example, by a laser cutter.

[0063] like Figure 4 As shown, the preferred conical portion 11 has a first conical surface S1, and the extension conduit 91 satisfies the following formulas (1) and (2).

[0064] θ1≤45° …(1)

[0065] θ2<45°…(2)

[0066] [In the formula, θ1 represents the angle between the opening surface 12S of the braided tube 12 and the first conical surface S1. θ2 represents the angle between the first conical surface S1 and the axial direction 10X of the cylindrical portion 10.]

[0067] As in formula (1), by setting θ1 to 45° or less, the opening containing surface 12S is nearly parallel to the first conical surface S1, making it less prone to deformation into a skewed shape near the opening containing surface 12S when the cylindrical portion 10 is bent. θ1 is more preferably 40° or less. On the other hand, θ1 is preferably 10° or more, and more preferably 20° or more. This increases the distance between the opening containing surface 12S and the first conical surface S1, thereby improving the flexibility of the conical portion 11.

[0068] As shown in equation (2), by having θ2 less than 45°, the opening area of ​​the opening 11P, which is located at least inside the first conical surface S1, can be increased. θ2 is more preferably 40° or less. On the other hand, θ2 is preferably 10° or more, and more preferably 15° or more. As a result, the endovascular treatment device is less likely to shake when inserted into the opening 11P.

[0069] As described above, the extension catheter 91 preferably satisfies equations (1) and (2), but it may also satisfy equation (1) or (2).

[0070] like Figure 4 As shown, the tapered portion 11 of the preferred cylindrical component 1 preferably has multiple tapered surfaces. Preferably, the multiple tapered surfaces of the tapered portion 11 include a first tapered surface S1 and a second tapered surface S2 located distal to the first tapered surface S1. Preferably, the second tapered surface S2 includes the distal end 11b of the tapered portion 11, and the angle formed with the axial direction 10X of the cylindrical portion 10 is greater than the angle θ2 formed by the first tapered surface S1 and the axial direction 10X of the cylindrical portion 10. This reduces the thin-walled portion near the distal end 11b of the tapered portion 11, making it less likely for endovascular therapeutic instruments to snag near the distal end 11b of the tapered portion 11. The angle formed by the second tapered surface S2 and the axial direction 10X of the cylindrical portion 10 is preferably 45° or more and 89° or less, more preferably 50° or more and 85° or less. Alternatively, the tapered portion 11 of the cylindrical component 1 may have only one tapered surface.

[0071] like Figure 4 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 at a position further away from the first conical surface S1; and a third conical surface S3 located at a position closer to the first conical surface S1. 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 θ2 formed by the first conical surface S1 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 and the second conical surface S2 are preferably adjacent to each other. The first conical surface S1 and the third conical surface S3 are preferably adjacent to each other. 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.

[0072] like Figure 4 As 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 θ2 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.

[0073] Preferably, the first conical surface S1 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 4 In the first conical surface S1 and the second conical surface S2, 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, and the first conical surface S1 has the largest area. Therefore, it is easier to obtain the effect of the first conical surface S1 described above in equations (1) and (2).

[0074] Preferably, the first conical surface S1 is the longest conical surface in the radial direction 1D of the cylindrical component 1 among the multiple conical surfaces. Figure 4 Among the first conical surface S1, the second conical surface S2, and the third conical surface S3, the first conical surface S1 has the longest radial length 1D. Therefore, it is easier to obtain the effects of equations (1) and (2) for the first conical surface S1 mentioned above.

[0075] like Figure 4 As shown, preferably in the radial direction 12D of the braided tube 12, 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. Because the first conical surface S1 is inclined in this way, it is easy to insert an endovascular therapeutic device from the opening 11P located at least inside the first conical surface S1. Similarly, preferably in the radial direction 12D of the braided tube 12, 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.

[0076] like Figure 5 As shown, the preferred braided tube 12 has a first wire 12W, which has a first inclined portion 12W1 that is inclined relative to the axial direction 10X of the tubular portion 10. The tubular portion 10 can be reinforced by such a braided tube 12, for example, so that the guide wire is less likely to penetrate the tubular portion 10 when it is inserted into the inner cavity of the tubular portion 10.

[0077] like Figure 4 , Figure 5 As shown, preferably in a field of view in which the conical surface of the conical portion 11 of the cylindrical member 1 is linear, the extension conduit 91 satisfies the following formula (3). Furthermore, in the radial direction 12D of the braided tube 12 in this field of view, the proximal side of the first inclined portion 12W1 is close to the linear member 2, and the distal side is far from the linear member 2.

[0078] θ3>θ4 …(3)

[0079] [In the formula, θ3 represents the angle formed by the opening surface 12S of the braided tube 12 and the axial direction 10X of the cylindrical portion 10. θ4 represents the angle formed by the first inclined portion 12W1 and the axial direction 10X of the cylindrical portion 10.]

[0080] As shown in equation (3), θ3 is greater than θ4, thereby easily preventing deformation of the opening containing surface 12S during operation. Specifically, the value of θ3-θ4, that is, the difference between θ3 and θ4, is preferably 1° or more, more preferably 5° or more. On the other hand, the difference between θ3 and θ4 is preferably 70° or less, more preferably 60° or less. As a result, the portion of the opening containing surface 12S and its vicinity in the braided tube 12 is easily bent.

[0081] like Figure 4 , Figure 6 As shown, preferably in a field of view in which the conical surface of the conical portion 11 of the cylindrical member 1 is linear, the extension conduit 91 satisfies the following formula (4). Furthermore, in the radial direction 12D of the braided tube 12 in this field of view, the proximal side of the first inclined portion 12W1 is close to the linear member 2, and the distal side is far away from the linear member 2.

[0082] θ3<θ4 …(4)

[0083] [In the formula, θ3 represents the angle formed by the opening surface 12S of the braided tube 12 and the axial direction 10X of the cylindrical portion 10. θ4 represents the angle formed by the first inclined portion 12W1 and the axial direction 10X of the cylindrical portion 10.]

[0084] As shown in equation (4), θ3 is less than θ4, so the portion of the braided tube 12 containing the surface 12S and its vicinity can be smoothly bent, making it easier to insert the cylindrical component 1, especially into the curved portion with a large curvature within the tube. Specifically, the value of θ4-θ3, i.e., the difference between θ4 and θ3, is preferably 1° or more, more preferably 5° or more. On the other hand, the difference between θ4 and θ3 is preferably 70° or less, more preferably 60° or less. As a result, it is easy to prevent the braided portion containing the surface 12S from unraveling during operation.

[0085] In a field of view where the conical surface of the conical portion 11 of the cylindrical member 1 is linear, the angle θ3 between the opening portion containing the surface 12S of the braided tube 12 and the axial direction 10X of the cylindrical portion 10 is preferably 89° or less, more preferably 80° or less, and even more preferably 70° or less. This allows the opening portion containing the surface 12S and the portion near it in the braided tube 12 to be easily bent. On the other hand, θ3 is preferably 20° or more, more preferably 30° or more. This makes it easy to prevent the braided portion containing the surface 12S of the opening from unraveling during operation.

[0086] In a field of view where the conical surface of the conical portion 11 of the cylindrical member 1 is linear, the angle θ4 formed by the first inclined portion 12W1 and the axial direction 10X of the cylindrical portion 10 is preferably 20° or more and 80° or less, more preferably 30° or more and 70° or less. This strengthens the cylindrical portion 10 while maintaining its flexibility to bend along curves within the body.

[0087] like Figure 5 , Figure 6 As shown, 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.

[0088] like Figure 4 As shown, the distal end 2b of the preferred linear member 2 is located more distally than the proximal end 12a of the braided tube 12. Therefore, when the tubular member 1 is inserted into the curved portion of the body, it can be smoothly bent in the order of the braided tube 12 and the portion closer to the proximal end of the braided tube 12. In this case, the distal end 2b of the linear member 2 can be more distally than the distal end 12Sb containing the surface 12S in the opening, or it can be closer to the proximal end 12Sb containing the surface 12S in the opening.

[0089] 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.

[0090] like Figure 4 As shown, in a field of view where the cylindrical member 1 is oriented linearly toward the first conical surface S1, the shortest distance L1 from the distal end 12Sb of the opening portion containing the surface 12S of the braided tube 12 to the first conical surface S1 is preferably at least 0.5 times the radial length L2 of the braided tube 12 at the distal end 12Sb of the opening portion containing the surface 12S. This allows the flexible portion of the cylindrical part 10 closer to the position of the opening portion containing the surface 12S to become longer. This ratio is more preferably at least 0.8 times, and even more preferably at least 0.9 times. On the other hand, this ratio is preferably 3.0 times or less, more preferably 2.0 times or less, and even more preferably 1.5 times or less. This easily prevents deformation during bending caused by the flexible portion of the cylindrical part 10 becoming too long closer to the position of the opening portion containing the surface 12S.

[0091] like Figure 4 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.

[0092] like Figure 7 As shown, the preferred cylindrical component 1 has an inner layer 10L and an outer layer 10M located radially outward from the inner layer 10L. By having an inner layer 10L and an outer layer 10M, the cylindrical component 1 can perform different functions on its inner and outer sides.

[0093] The inner layer 10L preferably contains a fluoropolymer, more preferably is composed of a fluoropolymer. Fluoropolymers have excellent chemical resistance, non-stick properties, and low friction. Fluoropolymers preferably include polytetrafluoroethylene, ethylene tetrafluoroethylene, fluorinated ethylene propylene, or combinations thereof.

[0094] The outer layer 10M preferably comprises polyamide resin, polyester resin, polyurethane resin, polyolefin resin, vinyl chloride resin, silicone resin, natural rubber, or a combination thereof, and more preferably comprises polyamide resin, polyurethane resin, or a combination thereof.

[0095] 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.

[0096] 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.

[0097] Preferably, the braided tube 12 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 prevents the braided tube 12 from being exposed into the inner cavity of the cylindrical part 10.

[0098] Preferably, the distal end 2B of the linear component 2 is disposed radially 1D between the inner layer 10L and the outer layer 10M, or within the outer layer 10M. This allows the linear component 2 to be easily and securely fixed to the cylindrical component 1. Furthermore, an adhesive such as a hot-melt adhesive may be attached to the outer surface of the linear component 2.

[0099] Preferably, the inner layer 10L and the outer layer 10M extend axially 10X from the cylindrical portion 10 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.

[0100] 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 easily getting caught 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 coils in the cylindrical portion 10, the conical portion 11, or both. By having a braided tube 12 and coils in the cylindrical component 1, flexibility is maintained, and the cylindrical component 1 is less likely to be flattened radially 1D. On the other hand, by not having coils in the cylindrical component 1, the radial length 1D of the cylindrical component 1 can be reduced.

[0101] like Figure 8As 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 preferred cross-sectional shape of the linear component 2 in the thickness direction is 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 can have a portion that tapers towards the distal end.

[0102] 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.

[0103] like Figure 9 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 9 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 outer layer 10M. 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.

[0104] 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.

[0105] 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.

[0106] This application claims a priority interest based on Japanese Patent Application No. 2024-032455, filed March 4, 2024. The entire contents of the description of Japanese Patent Application No. 2024-032455, filed March 4, 2024, are incorporated herein by reference.

[0107] Explanation of reference numerals in the attached figures

[0108] 1…Cylindrical component; 1D…Radial; 2…Wire-like component; 2b…Distal end; 2B…Distal end; 3…Handle component; 10…Cylindrical portion; 10L…Inner layer; 10M…Outer layer; 10X…Axial; 11…Tapered portion; 11a…Proximal end; 11b…Distal end; 11P…Opening; 12…Braided tube; 12a…Proximal end; 12b…Distal end; 12D…Radial; 12P…Opening; 12Q…Opening Part; 12S…Opening containing a surface; 12Sa…Proximal end; 12Sb…Distal end; 12W…First wire; 12W1…First inclined part; 13…X-ray impermeable ring; 91…Extending guide tube; 99…Guide tube; 99Pa…Proximal opening; 99Pb…Distal opening; 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 a cylindrical portion and a tapered portion located closer to the side of the cylindrical portion. The cylindrical component has a braided tube at least in the cylindrical portion. The opening, including the proximal opening of the braided tube, has an inclined surface. In the radial direction of the braided tube, the proximal end of the opening containing the face is closer to the linear member than the distal end of the opening containing the face.

2. The extension catheter according to claim 1, characterized in that, The conical part has a first conical surface and satisfies the following equations (1) and (2). θ1≤45° …(1) θ2<45° …(2) In the formula, θ1 represents the angle between the opening of the braided tube and the first conical surface, and θ2 represents the angle between the first conical surface and the axial direction of the cylindrical portion.

3. The extension catheter according to claim 2, characterized in that, The tapered portion has multiple tapered surfaces, and the first tapered surface is the tapered surface with the largest area among the multiple tapered surfaces that are inclined at an angle of more than 5° and less than 89° relative to the axial direction of the cylindrical portion.

4. The extension catheter according to claim 1 or 2, characterized in that, The braided tube has a first wire, the first wire having a first inclined portion that is axially inclined relative to the cylindrical portion. In the field of view when the cylindrical component is oriented toward the tapered surface of the tapered portion as a line, the following equation (3) is satisfied. θ3>θ4 …(3) In the formula, θ3 represents the angle between the opening of the braided tube and the axial direction of the cylindrical portion, and θ4 represents the angle between the first inclined portion and the axial direction of the cylindrical portion.

5. The extension catheter according to claim 1 or 2, characterized in that, The braided tube has a first wire, the first wire having a first inclined portion that is axially inclined relative to the cylindrical portion. In the field of view when the cylindrical component is oriented toward the tapered surface of the tapered portion as a line, the following equation (4) is satisfied. θ3<θ4 …(4) In the formula, θ3 represents the angle between the opening of the braided tube and the axial direction of the cylindrical portion, and θ4 represents the angle between the first inclined portion and the axial direction of the cylindrical portion.

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

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

8. The extension catheter according to claim 2, characterized in that, In a field of view with the cylindrical component oriented in a linear direction toward the first conical surface, the shortest distance from the distal end of the opening containing the surface of the braided tube to the first conical surface is at least 0.5 times the radial length of the braided tube at the distal end of the opening containing the surface of the braided tube.

9. The extension catheter according to claim 2, characterized in that, The proximal end of the braided tube is located on the distal side compared to the distal end of the first conical surface.

10. The extension catheter according to claim 1 or 2, characterized in that, The cylindrical component also has at least one X-ray impermeable ring configured as the proximal end, distal end, or both ends of the braided tube located inside.

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

12. The extension catheter according to claim 2, characterized in that, In the radial direction of the braided tube, the proximal end of the first tapered surface is closer to the linear component than the distal end of the first tapered surface.

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