Extension catheter

Abstract

Provided is an elongated catheter that is easy to insert into a body with a curved portion. 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 portion is fixed to the tubular member, the wire member having a first cutting surface on a side surface that faces outward in the radial direction of the tubular member.

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] As in Patent Document 1, in existing extension catheters, there are difficulties in inserting the cylindrical component, which is fixed to the distal end of the linear component, into a curved portion of the body such as an artery. The present invention addresses these issues, and its object is to provide an extension catheter that is easily inserted into a curved portion of 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 linear component has a first cutting surface on its side facing outward in the radial direction toward the aforementioned cylindrical component.

[0010] Through the inventors' research, it has been found that when manufacturing an extension catheter, if the cutting surface is fixed towards the cylindrical component after reducing the outer diameter by cutting the distal end of the linear component, the cutting surface of the linear component and its vicinity tend to bend away from the central axis of the cylindrical component due to residual cutting stress. On the other hand, as described above [1], it has been found that in a structure where the cutting surface of the linear component faces the side opposite to the cylindrical component, i.e., the radially outer side of the cylindrical component, the cutting surface and its vicinity tend to bend towards the central axis of the cylindrical component due to residual cutting stress. According to such a structure, when the cylindrical component is pushed into the curved portion of the body via the linear component, the linear component and the cylindrical component tend to bend along the shape of the curved portion of the body, thus making it easier to insert the extension catheter into the curved portion of the body. The extension catheter according to the preferred embodiment is any one of [2] to

[18] below.

[0011] [2] According to the elongation catheter described in [1], wherein,

[0012] At least a portion of the first cutting surface is located at the distal end.

[0013] [3] The elongation catheter as described in [1] or [2], wherein,

[0014] The aforementioned linear component has multiple cutting surfaces on the aforementioned side surface.

[0015] The first cutting surface mentioned above is the cutting surface with the largest area between the distal end of the aforementioned linear component and a position 20 cm away from the proximal side.

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

[0017] The aforementioned linear component, at least in the portion fixed to the aforementioned cylindrical component, does not have a cutting surface facing the inner side in the aforementioned radial direction.

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

[0019] The first cutting surface is inclined relative to the axial direction of the cylindrical component, and in the radial direction, the distal end of the first cutting surface is located inside the proximal end.

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

[0021] The first cutting surface does not have a portion that is parallel to the axial direction of the cylindrical component.

[0022] [7] The elongation catheter described in any one of [3] to [6], wherein,

[0023] The proximal end of the cutting surface that is closest to the cutting surface among the above-mentioned multiple cutting surfaces is located closer to the side than the proximal end of the above-mentioned cylindrical component.

[0024] [8] The elongation catheter described in any one of [1] to [7], wherein,

[0025] The aforementioned linear component has: a first portion including the aforementioned first cutting surface; and a second portion located closer to the side than the first portion and without a cutting surface on the aforementioned side surface.

[0026] In the cross-section of the linear component in the radial direction of the cylindrical component, the ratio of the major diameter to the minor diameter of the first component is larger than that of the second component.

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

[0028] The proximal end of the first part is located closer to the side than the proximal end of the cylindrical component.

[0029]

[10] The elongation catheter as described in [8] or [9], wherein,

[0030] The length of the first part is less than 10% of the length of the linear component.

[0031]

[11] The elongation catheter described in any one of [8] to

[10] , wherein,

[0032] The first part is located between the distal end of the cylindrical component and a distance of 20 cm or more and 40 cm or less from the distal end of the cylindrical component.

[0033]

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

[11] , wherein,

[0034] The aforementioned cylindrical component has a reinforcing layer.

[0035]

[13] According to the elongation catheter described in

[12] , wherein,

[0036] The distal end of the aforementioned linear component is located on the distal side compared to the proximal end of the aforementioned reinforcing layer.

[0037]

[14] According to the elongation catheter described in

[12] , wherein,

[0038] The distal end of the aforementioned linear component is located closer to the side of the position than the proximal end of the aforementioned reinforcing layer.

[0039]

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

[14] , wherein,

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

[0041]

[16] According to the elongation catheter described in

[15] , wherein,

[0042] The distal end of the first cutting surface is located at the distal end of the linear component.

[0043] The distal end of the tapered portion of the cylindrical component is located closer to the distal end of the first cutting surface and further to the distal end of the first cutting surface.

[0044]

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

[16] , wherein,

[0045] The aforementioned linear component is a solid linear component without an internal cavity.

[0046]

[18] The elongation catheter described in any one of

[15] to

[17] , wherein,

[0047] 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.

[0048] According to the present invention, it is possible to provide an extension catheter with a curved portion that is easy to insert into the body. Attached Figure Description

[0049] Figure 1 This is a side view of the extension catheter involved in the embodiment.

[0050] 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.

[0051] Figure 3 yes Figure 1 A cross-sectional view of the tapered portion of the extended catheter and its vicinity along the axial direction.

[0052] Figure 4 yes Figure 1 Sectional view of the extended catheter (IV-IV).

[0053] Figure 5 yes Figure 1 VV sectional view of the extended catheter.

[0054] Figure 6 It is inserted into the bent guiding catheter. Figure 1 Side view of the extended catheter.

[0055] Figure 7 yes Figure 1A side view of a modified example of the linear component of the extended conduit.

[0056] Figure 8 yes Figure 1 A side view of a modified example of the linear component of the extended conduit.

[0057] Figure 9 yes Figure 1 IX-IX sectional view of the extended catheter.

[0058] Figure 10 yes Figure 1 A side view of the conical portion of the extended catheter and its vicinity.

[0059] Figure 11 It has an X-ray impermeable ring. Figure 1 Side view of the extended catheter. Detailed Implementation

[0060] 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, component reference numerals 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.

[0061] 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, the distal end of which is fixed to the cylindrical member. The linear member has a first cutting surface on its side facing the radially outer side of the cylindrical member. Through the inventors' research, it has been found that when manufacturing the extension catheter, if the cutting surface is fixed towards the cylindrical member while reducing the outer diameter by cutting the distal end of the linear member, the cutting surface of the linear member and its vicinity tend to bend away from the central axis of the cylindrical member due to residual cutting stress. On the other hand, as described above, it has been found that in a structure where the cutting surface of the linear member faces the side opposite to the cylindrical member, i.e., the radially outer side of the cylindrical member, the cutting surface and its vicinity tend to bend towards the central axis of the cylindrical member due to residual cutting stress. According to this structure, when the cylindrical member is pushed into the curved portion of the body via the linear member, the linear member and the cylindrical member tend to bend along the shape of the curved portion within the body, thus facilitating the insertion of the extension catheter into the curved portion of the body.

[0062] The following is for reference Figures 1-11 The extension catheter involved in the implementation method will be described. Figure 1This 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 guiding catheter, with a portion 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 , Figure 5 , Figure 9 In order are Figure 1 Sectional views IV-IV, VV, and IX-IX of the extension catheter. Figure 6 It is inserted into the bent guiding catheter. Figure 1 Side view of the extended catheter. Figure 7 , Figure 8 They are Figure 1 A side view of a modified example of the linear component of the extended conduit. Figure 10 yes Figure 1 A side view of the conical portion of the extended catheter and its vicinity. Figure 11 It has an X-ray impermeable ring. Figure 1 Side view of the extended catheter.

[0063] 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.

[0064] 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.

[0065] like Figure 3 , Figure 4 , Figure 5 As shown, the linear component 2 has a first cutting surface 2S1 on its side, extending radially 1D toward the cylindrical component 1 from the outer side 1D1. Due to residual stress from the formation of the first cutting surface 2S1 on the linear component 2, the first cutting surface 2S1 and its vicinity tend to bend radially 1D toward the inner side 1D2 of the cylindrical component 1. As a result, as... Figure 6 As shown, when the cylindrical portion 10 is pushed into the curved portion of the body via the linear member 2, the cylindrical portion 10 and the linear member 2 easily bend along the shape of the curved portion, thus facilitating the insertion of the extension catheter 91 into the curved portion of the body. The outer side 1D1 of the first cutting surface 2S1 toward the radial direction 1D of the cylindrical member 1 refers to the direction of the first cutting surface 2S1 toward the direction opposite to the direction toward the central axis 1C of the cylindrical member 1 along the radial direction 1D of the cylindrical member 1. On the other hand, the inner side 1D2 of the first cutting surface 2S1 toward the radial direction 1D of the cylindrical member 1 refers to the direction of the first cutting surface 2S1 toward the direction toward the central axis 1C of the cylindrical member 1 along the radial direction 1D of the cylindrical member 1. Hereinafter, the radial direction 1D of the cylindrical member 1 will sometimes be simply referred to as radial 1D.

[0066] like Figure 3 As shown, preferably at least a portion of the first cutting surface 2S1 is located at the distal end 2B of the linear member 2. This allows the portion of the cylindrical member 1 to which the distal end 2B of the linear member 2 is fixed to bend easily toward the inner side 1D2 in the radial direction 1D of the cylindrical member 1.

[0067] Preferably, the distal end 2S1b of the first cutting surface 2S1 is located at the distal end 2b of the linear component 2. This allows the linear component 2 to be easily bent from the distal end 2b.

[0068] Preferably, the proximal end 2S1a of the first cutting surface 2S1 is located closer to the side than the proximal end 1a of the cylindrical member 1. As a result, the portion of the cylindrical member 1 to which the distal end 2B of the wire member 2 is fixed is more likely to bend toward the inner side 1D2 of the radial direction 1D of the cylindrical member 1.

[0069] Preferably, the first cutting surface 2S1 is inclined relative to the axial direction 1X of the cylindrical member 1, and in the radial direction 1D, the distal end 2S1b of the first cutting surface 2S1 is located more inward than the proximal end 2S1a. By inclining the first cutting surface 2S1 in this way, the first cutting surface 2S1 of the linear member 2 and its vicinity are more easily bent toward the inner side 1D2 in the radial direction 1D of the cylindrical member 1.

[0070] Preferably, the first cutting surface 2S1 does not have a portion parallel to the axial direction 1X of the cylindrical component 1. As a result, the first cutting surface 2S1 of the linear component 2 and its vicinity are more likely to bend toward the inner side 1D2 of the radial direction 1D of the cylindrical component 1.

[0071] like Figure 7 As shown, the linear component 2 may also have multiple cutting surfaces on its side. In this case, the multiple cutting surfaces preferably include a first cutting surface 2S1 located at the farthest side and a second cutting surface 2S2 located closer to the side than the first cutting surface 2S1. Preferably, the first cutting surface 2S1 and the second cutting surface 2S2 face outwards 1D1 in the radial direction 1D of the cylindrical component 1. The angles formed by the first cutting surface 2S1 and the second cutting surface 2S2 with the axial direction 2X of the linear component 2 are preferably 0.1° or more and 45° or less, more preferably 0.2° or more and 30° or less, and even more preferably 0.2° or more and 5° or less. Preferably, the angle formed by the first cutting surface 2S1 with the axial direction 2X of the linear component 2 is smaller than the angle formed by the second cutting surface 2S2 with the axial direction 2X of the linear component 2. In addition, preferably, the first cutting surface 2S1 is longer than the second cutting surface 2S2 in the axial direction 2X of the linear component 2. This increases the area of ​​the first cutting surface 2S1, making it easier for the curved portion of the linear component 2 to bend within the body. On the other hand, the angle between the first cutting surface 2S1 and the axial direction 2X of the linear member 2 can also be greater than the angle between the second cutting surface 2S2 and the axial direction 2X of the linear member 2. Furthermore, in the axial direction 2X of the linear member 2, the first cutting surface 2S1 can be shorter than the second cutting surface 2S2. This improves the strength near the distal end 2b of the linear member 2.

[0072] like Figure 7 As shown, preferably, multiple cutting surfaces are respectively oriented towards the outer side 1D1 of the cylindrical member 1 in the radial direction 1D and inclined relative to the axial direction 1X of the cylindrical member 1, with the distal end of each cutting surface in the radial direction 1D located further inward than the proximal end. Therefore, the multiple cutting surfaces of the linear member 2 and their vicinity are more easily bent towards the inner side 1D2 of the cylindrical member 1 in the radial direction 1D. Furthermore, the multiple cutting surfaces may also have cutting surfaces parallel to the axial direction 1X of the cylindrical member 1.

[0073] Preferably, the proximal end of the nearest cutting surface among multiple cutting surfaces is located closer to the position than the proximal end 1a of the cylindrical component 1. For example, Figure 7 As shown, when multiple cutting surfaces have a first cutting surface 2S1 and a second cutting surface 2S2 located closer to the position side than the first cutting surface 2S1, it is preferable that the proximal end 2S2a of the second cutting surface 2S2 is located closer to the position side than the proximal end 1a of the cylindrical member 1. Therefore, the portion of the cylindrical member 1 to which the distal end 2B of the wire-like member 2 is fixed is more likely to bend towards the inner side 1D2 in the radial direction 1D of the cylindrical member 1.

[0074] Preferably, the first cutting surface 2S1 is the cutting surface with the largest area between the distal end 2b of the linear component 2 and a position 20 cm away from the proximal side. As a result, the distal end 2B of the linear component 2 can easily bend toward the inner side 1D2 of the radial direction 1D of the cylindrical component 1.

[0075] like Figure 3 , Figure 4 , Figure 5 As shown, preferably, the linear member 2 does not have a cutting surface facing the inner side 1D2 in the radial direction 1D, at least in the portion fixed to the cylindrical member 1. This makes it easier for the distal end 2B of the linear member 2 to bend towards the inner side 1D2 in the radial direction 1D of the cylindrical member 1.

[0076] On the other hand, such as Figure 8 As shown, the linear component 2 may also have an inwardly facing cutting surface 2S3 toward the inner side 1D2 in the radial direction 1D. In this case, as... Figure 8 As shown, preferably, the length H1 of the first cutting surface 2S1 in the radial direction 1D is longer than the length H3 of the inward cutting surface 2S3 in the radial direction 1D. In such a structure, the residual stress in the direction toward the inner side 1D2 is greater than the residual stress in the direction toward the outer side 1D1 in the radial direction 1D of the cylindrical member 1, so the first cutting surface 2S1 and its vicinity are prone to bend toward the inner side 1D2 in the radial direction 1D of the cylindrical member 1. Preferably, at least a portion of the inward cutting surface 2S3 is located at the distal end 2B of the linear member 2. Furthermore, preferably, the distal end 2S3b of the inward cutting surface 2S3 is located at the distal end 2b of the linear member 2. This allows for a reduction in the outer diameter of the distal end 2b of the linear member 2 and its vicinity.

[0077] like Figure 1 , Figure 3 As shown, the preferred linear component 2 has: a first portion 2P1, including a first cutting surface 2S1; and a second portion 2P2, located closer to the first portion 2P1 than the first portion 2P1 and without a cutting surface on its side. Furthermore, as... Figure 4 , Figure 5 , Figure 9 As shown, preferably in the cross-section of the linear member 2 along the radial direction 1D of the cylindrical member 1, the ratio of the major axis to the minor axis of the first part 2P1 is larger than that of the second part 2P2. A larger major axis / minor axis ratio makes it easier to bend in one direction and exhibit anisotropy. Therefore, a larger major axis / minor axis ratio in the first part 2P1 facilitates easy insertion of the curved portion into the body from the distal side of the linear member 2. The minor axis refers to the length of the shortest line segment connecting two points on the outer edge of the linear member 2 and passing through the centroid of the linear member 2 in each cross-section. The major axis refers to the length of the longest line segment connecting two points on the outer edge of the linear member 2 and passing through the centroid of the linear member 2 in each cross-section. Furthermore, the first part 2P1 may also have multiple cutting surfaces.

[0078] like Figure 1 , Figure 3 As shown, preferably, the proximal end 2P1a of the first portion 2P1 is located closer to the side than the proximal end 1a of the cylindrical member 1. Therefore, the portion of the cylindrical member 1 to which the distal end 2B of the wire member 2 is fixed is more likely to bend towards the inner side 1D2 in the radial direction 1D of the cylindrical member 1.

[0079] The length of the first portion 2P1 is preferably 10% or less of the length of the linear member 2. This reduces the length of the anisotropic portion of the linear member 2, making it easier, for example, to insert the linear member 2 relative to the straight portion of a blood vessel. More preferably, the length of the first portion 2P1 is 9% or less of the length of the linear member 2. On the other hand, the length of the first portion 2P1 is preferably 1% or more of the length of the linear member 2, more preferably 2% or more. This allows the distal side of the linear member 2 to be easily inserted into the curved portion of the body.

[0080] Preferably, the first portion 2P1 is located between the distal end 1b of the cylindrical member 1 and a distance of 20 cm to 40 cm from the distal end 1b of the cylindrical member 1. By having at least a portion of the first portion 2P1 located within this range, the cylindrical member 1 can be easily inserted into the curved portion of the body.

[0081] like Figure 4 , Figure 5 , Figure 9 As 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 component 1 distally, and its material is not particularly limited. It preferably includes stainless steel, titanium, nickel-titanium alloy, cobalt-chromium alloy, tungsten alloy, or a combination thereof, and more preferably stainless steel.

[0082] The cutting surface of the side of the wire component 2 can be formed, for example, by grinding the side of a wire with a circular cross-sectional shape in the thickness direction using a grinding machine. The cross-sectional shape in the thickness direction of the wire is not limited to a circle; for example, it can also be a polygon, an ellipse, etc.

[0083] The linear component 2 preferably has a cross-sectional shape in the thickness direction that is a convex polygon, a concave polygon, a circle, a D-shape, or an ellipse. A convex polygon can be a square, rectangle, trapezoid, or hexagon. The linear component 2 at the first portion 2P1 preferably has a cross-sectional shape in the thickness direction that is D-shaped, rectangular, or elliptical. This makes it easier for the first portion 2P1 to exhibit anisotropy. On the other hand, the linear component 2 at the second portion 2P2 is preferably circular or a regular polygon. This makes it difficult for the second portion 2P2 to exhibit anisotropy.

[0084] like Figure 4and Figure 9 As shown, the cross-sectional shapes of the linear components 2 in the thickness direction at the first part 2P1 and the second part 2P2 are preferably different. This makes it easier to perform the respective functions of the first part 2P1 and the second part 2P2.

[0085] like Figure 4 and Figure 9 As shown, preferably, the cross-sectional area of ​​the linear component 2 in the thickness direction at the first part 2P1 is smaller than the cross-sectional area of ​​the linear component 2 in the thickness direction at the second part 2P2. This makes the first part 2P1 easier to bend.

[0086] 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.

[0087] like Figure 1 , Figure 10 As shown, the preferred cylindrical member 1 has a cylindrical portion 10 and a tapered portion 11 located closer to the side of the cylindrical portion 10. The tapered portion 11 is shorter than the cylindrical portion 10 in the radial direction 1D of the cylindrical member 1 and has an opening 11P communicating with the inner cavity of the cylindrical member 1 and facing radially 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 6 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.

[0088] like Figure 10 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 3 As 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.

[0089] like Figure 10As 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.

[0090] like Figure 10 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.

[0091] like Figure 10 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 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.

[0092] 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 10 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. Therefore, the aforementioned inclination effect of the second conical surface S2 is more easily achieved.

[0093] 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 10 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.

[0094] like Figure 10 As shown, preferably, in the radial direction 1D of the cylindrical member 1, the proximal end of the conical surface of the conical portion 11 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 an endovascular treatment device from 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.

[0095] like Figure 3 As shown, preferably, the distal end 2S1b of the first cutting surface 2S1 is located at the distal end 2b of the linear member 2, and the distal end 11b of the tapered portion 11 of the cylindrical member 1 is located closer to the distal end 2S1b of the first cutting surface 2S1 and further to the distal end 2S1a of the first cutting surface 2S1. Therefore, when the cylindrical member is pushed into the curved portion of the body via the linear member 2, it is easy to bend in the order of the cylindrical portion 10 and the tapered portion 11.

[0096] like Figure 3 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.

[0097] 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.

[0098] The outer layer 10M preferably comprises polyamide resin, polyester resin, polyurethane resin, polyolefin resin, vinyl chloride resin, silicone resin, natural rubber, or combinations thereof, and more preferably comprises polyamide resin, polyurethane resin, or combinations thereof. The resin may also include an elastomer with rubber-like elasticity. For example, polyamide resin may include a polyamide elastomer, and polyurethane resin may include a polyurethane elastomer.

[0099] 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.

[0100] 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.

[0101] 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.

[0102] 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.

[0103] 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 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.

[0104] Preferably, the cylindrical component 1 has a reinforcing layer 12. Specifically, the cylindrical component 1 preferably has a reinforcing layer 12 at least in the cylindrical portion 10. The reinforcing layer 12 can strengthen the cylindrical portion 10, for example, making it less likely for the guidewire to penetrate the cylindrical portion 10 when it is inserted into the inner cavity of the cylindrical portion 10.

[0105] The reinforcing layer 12 preferably includes a coil, a braided tube, or a combination thereof. By having a coil or a braided tube, or even both, in the reinforcing layer 12, flexibility is maintained and the cylindrical member 1 is less likely to be flattened in the radial direction 1D. On the other hand, by not having a coil or a braided tube in the reinforcing layer 12, the radial length 1D of the cylindrical member 1 can be reduced. Preferably, the braided tube has a mesh structure formed by braiding multiple wires in an interlaced manner. Each wire can be a single wire or a stranded wire.

[0106] As a wire, the reinforcing layer 12 preferably comprises a metal wire, fiber, or a combination thereof, more preferably a metal wire. The metal wire preferably comprises 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 comprises 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.

[0107] More preferably, the cylindrical member 1 has a reinforcing layer 12 in the cylindrical portion 10 but not in the tapered portion 11. This makes the tapered portion 11 easier to bend. Furthermore, it is preferable that the distal end 12b of the reinforcing layer 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 to be applied to the vicinity of the distal end of the cylindrical portion 10.

[0108] like Figure 10 As shown, preferably, the proximal end 12a of the reinforcing layer 12 is located on the distal side of the first conical surface S1 compared to the distal end S1b. This allows the first conical surface S1 and its vicinity to bend easily. More preferably, the proximal end 12a of the reinforcing layer 12 is located on the distal side of the conical portion 11 compared to the distal end 11b. This allows the conical portion 11 to bend easily.

[0109] Preferably, the reinforcing layer 12 is disposed in the radial direction 1D of the cylindrical member 1 between the inner layer 10L and the outer layer 10M, or within the outer layer 10M. This prevents the reinforcing layer 12 from being exposed into the inner cavity of the cylindrical portion 10.

[0110] like Figure 3 As shown, the distal end 2b of the preferred linear component 2 is located further distally than the proximal end 12a of the reinforcing layer 12. Therefore, through the first cutting surface 2S1 of the linear component 2, the cylindrical component 1 can be more easily bent toward the inner side 1D2 in the radial direction 1D.

[0111] 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 reinforcing layer 12. This reduces the outer diameter of the cylindrical portion 10 where the reinforcing layer 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 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 closer to the position side of the distal end 11b of the conical portion 11.

[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 reinforcing layer 12 with both ends located inside. Figure 11 In this configuration, the X-ray-impermeable ring 13 is disposed at the distal end 12b of the reinforcing layer 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 reinforcing layer 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 reinforcing layer 12 and the outer layer 10M. This suppresses the spreading of the ends of the reinforcing layer 12 and easily prevents the reinforcing layer 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 the benefit of priority based on Japanese Patent Application No. 2024-032460, filed on March 4, 2024. The entire contents of the description of Japanese Patent Application No. 2024-032460, filed on March 4, 2024, are incorporated herein by reference.

[0116] Explanation of reference numerals in the attached figures

[0117] 1…Cylindrical component; 1C…Central axis; 1D…Radial; 1D1…Outer side; 1D2…Inner side; 1X…Axial direction; 2…Linear component; 2b…Distal end; 2B…Distal end; 2P1…First part; 2P1a…Proximal end; 2P2…Second part; 2S1…First cutting surface; 2S1a…Proximal end; 2S1b…Distal end; 2S2…Second cutting surface; 2S2a…Proximal end; 2S3…Inward cutting surface; 2S3b…Distal end; 2X…Axial direction; 3…Handle component; 10…Cylindrical portion; 10 L…Inner layer; 10M…Outer layer; 10X…Axial direction; 11…Cone portion; 11a…Proximal end; 11b…Distal end; 11P…Opening; 12…Reinforcing layer; 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; H1, H3…Radial length; S1, S2, S3…First cone surface, second cone surface, third cone 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 linear component has a first cutting surface on its side that is radially outward toward the cylindrical component.

2. The extension catheter according to claim 1, characterized in that, At least a portion of the first cutting surface is located at the distal end.

3. The extension catheter according to claim 1 or 2, characterized in that, The linear component has multiple cut surfaces on its side. The first cutting surface is the cutting surface with the largest area between the distal end of the linear component and a position 20 cm away from the proximal side.

4. The extension catheter according to claim 1 or 2, characterized in that, The linear component does not have a cutting surface facing the inner side in the radial direction, at least in the portion fixed to the cylindrical component.

5. The extension catheter according to claim 1 or 2, characterized in that, The first cutting surface is inclined relative to the axial direction of the cylindrical component, and in the radial direction, the distal end of the first cutting surface is located inside the proximal end.

6. The extension catheter according to claim 1 or 2, characterized in that, The first cutting surface does not have a portion that is parallel to the axial direction of the cylindrical component.

7. The extension catheter according to claim 3, characterized in that, The proximal end of the nearest cutting surface among the plurality of cutting surfaces is located closer to the side than the proximal end of the cylindrical component.

8. The extension catheter according to claim 1 or 2, characterized in that, The linear component has: a first portion including the first cutting surface; and a second portion located closer to the side of the first portion and not having a cutting surface on that side. In the cross-section of the linear member in the radial direction of the cylindrical member, the ratio of the major diameter to the minor diameter of the first portion is larger than that of the second portion.

9. The extension catheter according to claim 8, characterized in that, The proximal end of the first portion is located closer to the side than the proximal end of the cylindrical component.

10. The extension catheter according to claim 8, characterized in that, The length of the first part is less than 10% of the length of the linear component.

11. The extension catheter according to claim 8, characterized in that, The first portion is located between the distal end of the cylindrical component and a distance of more than 20 cm and less than 40 cm from the distal end of the cylindrical component.

12. The extension catheter according to claim 1 or 2, characterized in that, The cylindrical component has a reinforcing layer.

13. The extension catheter according to claim 12, characterized in that, The distal end of the linear component is located on the distal side compared to the proximal end of the reinforcing layer.

14. The extension catheter according to claim 12, characterized in that, The distal end of the linear component is located closer to the position than the proximal end of the reinforcing layer.

15. 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 cylindrical portion than the cylindrical portion.

16. The extension catheter according to claim 15, characterized in that, The distal end of the first cutting surface is located at the distal end of the linear component. The distal end of the tapered portion of the cylindrical component is located closer to the distal end of the first cutting surface and further to the distal end of the first cutting surface.

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 15, 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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