Method for manufacturing an electrode catheter

Abstract

To provide an electrode catheter in which a gap is hardly generated between a conductor wire hole formed on a shaft, and a conductor wire, and which can be produced easily, and a production method of the electrode catheter.SOLUTION: There is provided a production method of an electrode catheter 1 comprising: a preparing step for preparing a shaft 10 which extends in a longitudinal axis direction and has a lumen, an electrode 20, and a conductor wire 30; a sharpening step for sharpening a first end of the conductor wire 30; a hole formation step for piercing the first end of the conductor wire 30 to the shaft 10, for forming a hole 13 in which the lumen communicates with the outside on the shaft 10; a conductor wire connecting step for connecting a second end 32 of the conductor wire 30 to the electrode 20; and an electrode arranging step for arranging the electrode 20 on the outside of the hole 13.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an electrode catheter used for measuring electrical potentials of internal organs, mainly the heart, and for cauterizing internal tissue. [Background technology]

[0002] Electrode catheters are primarily used as medical devices to diagnose arrhythmias by measuring cardiac potentials and to treat arrhythmias by applying high-frequency current to cauterize internal tissue. Typically, electrode catheters have multiple ring-shaped electrodes attached to the exterior of a hollow cylindrical shaft. Conductors connected to the inside of the ring electrodes extend from a conductor hole in the shaft through the shaft's inner cavity to an electrocardiogram monitor. A connector is used to connect the conductors to the electrocardiogram monitor. For example, by inserting an electrode catheter into a patient's heart and connecting the connector to an electrocardiogram monitor, it is possible to measure the electrocardiogram near the ring electrodes and accurately determine the condition of the myocardium that may be causing the arrhythmia.

[0003] If a liquid such as blood enters the gap between the electrode and the shaft and flows into the lumen of the shaft through the lead hole, it can cause short circuits between multiple leads and corrosion of the leads and the internal structure of the electrode catheter, resulting in failure of the electrode catheter. Furthermore, if liquid enters the lumen of the shaft, the baseline potential of the electrocardiogram measured by the electrode catheter becomes unstable, a phenomenon known as drift, making it difficult to perform accurate potential measurement and ablation. To prevent electrode catheter failure and to perform accurate potential measurement and ablation using the electrode catheter, it is necessary to prevent liquid from entering the lumen of the shaft.

[0004] As an example of an electrode catheter that prevents liquid from seeping into the lumen of the shaft, Patent Document 1 describes an electrode catheter that comprises a catheter body, a control handle, a catheter tip, multiple ring-shaped electrodes, and multiple lead wires, and that has side holes formed in the tubular wall of the catheter tip that run from the outer surface to the lumen, corresponding to the fixed positions of the ring electrodes, and that each of the multiple lead wires is joined to the inner surface of the ring electrode at its tip, thereby connecting to the ring electrode, and that enter the lumen of the catheter tip from the side holes and extend into the lumen of the catheter tip, the lumen of the catheter body, and the inner hole of the control handle, and that has an insulating resin thin film formed on the surface of at least the metal core wire at the tip of the lead wire and on the surface of the joint where it joins the inner surface of the ring electrode.

[0005] Patent Document 2 describes a catheter including a resin tube and a ring-shaped electrode arranged on the outside of the resin tube, in which the outer surface of the ring-shaped electrode is located more inward than the outer surface of the resin tube in a portion where the ring-shaped electrode is not arranged, and a conductor wire electrically connected to an external power source is attached to the ring-shaped electrode, and the conductor wire passes through a hole that penetrates radially through the resin tube and is in close contact with the inner surface of the hole, and the catheter has a shape in which the long axis of the opening surface of the hole is oriented parallel to the longitudinal direction of the resin tube, for example, in an elliptical shape.

[0006] Patent Document 3 describes an electrode catheter having a cylindrical body with an opening formed on the side, a ring electrode that covers the opening of the cylindrical body from the outside, a conductive member connected to the ring electrode and blocking at least a part of the opening, and a lead wire connected to the conductive member and arranged inside the cylindrical body, wherein the opening area of ​​the opening becomes smaller toward the axis of the cylindrical body and the conductive member has a cone-shaped portion that tapers toward the axis of the cylindrical body.

[0007] Patent Document 4 describes a guidewire-type electrode catheter having a tube body, a connector, and an electrode group consisting of multiple electrodes, in which the tube body has an electrode group formed by connecting and fixing the tips of lead wires to the side of the tip side, and a side hole corresponding to the fixed position of the electrode group, the lead wires extending from the side hole through the inside of the tube body to the connector, the metal core wire part of the electrode having its tip resin coating stripped off is welded to the inside by resistance welding or the like, and the rear end of the lead wire welded to the electrode is connected from the side hole through the inside of the tube body to the connector, and a sealant is provided on both side surfaces of the tip and rear end of the electrode, in the gap between the electrode and the outer surface of the first tube body, and in the gap between the inside of the electrode and the lead wire in the side hole of the first tube body, and the metal core wire of the lead wire is adhesively bonded within the sealant, including the resin coating, so that it does not become exposed from the sealant. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-268696 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-116309 [Patent Document 3] Japanese Patent Application Laid-Open No. 2016-137019 [Patent Document 4] Patent Publication No. 2021-27974 Summary of the Invention [Problem to be solved by the invention]

[0009] In the electrode catheter of Patent Document 1, an insulating resin thin film is formed on the surface of the metal core wire at the tip of the lead wire and on the surface of the joint where the lead wire and the inner surface of the ring-shaped electrode are joined. However, it is very difficult to form the insulating resin thin film so that no gaps are formed between the ring-shaped electrode and the lead wire and the catheter wall, making it difficult to improve manufacturing efficiency.

[0010] In the catheter of Patent Document 2, the ring-shaped electrode and lead wire are attached to the resin tube by thermally expanding the resin tube, but it can be difficult to precisely adjust the expansion of the resin tube, and there is room for improvement in terms of making manufacturing easier.

[0011] In the electrode catheter of Patent Document 3, when manufacturing the electrode catheter, it can be difficult to form an opening in the cylindrical body whose opening area decreases toward the axis of the cylindrical body, or to manufacture a conductive member having a cone-shaped portion that tapers toward the axis of the cylindrical body.

[0012] The electrode catheter of Patent Document 4 is provided with sealant on both the front and rear side surfaces of the electrode, in the gap between the electrode and the outer surface of the first tube body, and in the gap between the inside of the electrode and the lead wire in the side hole of the first tube body, but it is difficult to provide sealant without leaving any gaps, making it difficult to manufacture.

[0013] The present invention has been made in consideration of the above circumstances, and its object is to provide a method for manufacturing an electrode catheter that is easy to manufacture and in which gaps are less likely to occur between the conductor hole formed in the shaft and the conductor. [Means for solving the problem]

[0014] The first method for manufacturing an electrode catheter that can solve the above problem includes a preparation step of preparing a shaft extending in the longitudinal direction and having an inner lumen, an electrode, and a conductor; a sharpening step of sharpening the first end of the conductor; a hole forming step of inserting the first end of the conductor into the shaft to form a hole in the shaft that connects the inner lumen to the outside; a conductor connecting step of connecting the second end of the conductor to the electrode; and an electrode placement step of placing the electrode outside the hole.

[0015] In the method for producing an electrode catheter of the present invention, the sharpening step preferably includes cutting the first end of the conductor wire so that the first end of the conductor wire has an acute angle.

[0016] In the method for producing an electrode catheter of the present invention, it is preferable to have a conductor heating step of heating the first end of the conductor before the hole forming step.

[0017] A second method for manufacturing an electrode catheter that can solve the above problem includes a preparation step of preparing a shaft extending in the longitudinal direction and having an inner lumen, an electrode, and a conductor; a conductor heating step of heating a first end of the conductor; a hole forming step of inserting the first end of the conductor into the shaft to form a hole in the shaft that connects the inner lumen to the outside; a conductor connecting step of connecting the second end of the conductor to the electrode; and an electrode placement step of placing the electrode outside the hole.

[0018] In the method for producing an electrode catheter of the present invention, it is preferable to have a sharpening step of sharpening the first end of the lead wire before the hole forming step.

[0019] In the method for producing an electrode catheter of the present invention, it is preferable to have a conductor cutting step of cutting the first end of the conductor after the hole forming step.

[0020] In the method for manufacturing an electrode catheter of the present invention, it is preferable that the second end of the conductive wire is located outside the shaft after the electrode placement step. [Effects of the Invention]

[0021] According to the first electrode catheter manufacturing method of the present invention, the method includes a sharpening step of sharpening the first end of the conductor wire and a hole forming step of piercing the first end of the conductor wire into the shaft to form a hole in the shaft that connects the inner cavity to the outside.This makes it possible to easily form a hole in the shaft that is less likely to create a gap between the conductor wire and the shaft, thereby improving the manufacturing efficiency of electrode catheters that make it less likely for liquids such as blood to penetrate into the inner cavity of the shaft.

[0022] In addition, according to the second electrode catheter manufacturing method of the present invention, the method includes a conductor heating step of heating the first end of the conductor, and a hole forming step of inserting the first end of the conductor into the shaft to form a hole in the shaft that connects the inner cavity with the outside. This makes it easy to form a hole in the shaft, and makes it difficult for gaps to form between the conductor and the hole, making it possible to easily manufacture an electrode catheter that is less likely to allow liquid to penetrate into the inner cavity of the shaft. [Brief explanation of the drawings]

[0023] [Figure 1] 1 shows an overall view of an electrode catheter according to one embodiment of the present invention. [Figure 2] 2 shows a cross-sectional view along the longitudinal axis of the electrode catheter shown in FIG. 1. [Figure 3] 4 shows an enlarged view of a first end of a conductor wire during a sharpening process in one embodiment of the present invention. [Figure 4] 10A and 10B are cross-sectional views taken along the longitudinal axis direction of a shaft during a hole forming step in one embodiment of the present invention. [Figure 5] 10A and 10B are cross-sectional views taken along the longitudinal axis direction of a shaft in a lead wire connecting step according to an embodiment of the present invention. [Figure 6] 10A and 10B are cross-sectional views taken along the longitudinal axis direction of a shaft in an electrode placement step according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] The present invention will be described in more detail below based on the following embodiments. However, the present invention is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the above and below-described purposes, and all such modifications are included within the technical scope of the present invention. For convenience, hatching and component symbols may be omitted in the drawings. In such cases, reference should be made to the specification or other drawings. The dimensions of various components in the drawings may differ from actual dimensions, as priority is given to helping understand the features of the present invention.

[0025] Fig. 1 is an overall view of an electrode catheter 1 in one embodiment of the present invention, and Fig. 2 is a cross-sectional view taken along the longitudinal axis of the distal end of the electrode catheter 1. As shown in Figs. 1 and 2, the electrode catheter 1 includes a shaft 10 extending in the longitudinal axis direction and having a lumen, an electrode 20, and a lead wire 30.

[0026] In the present invention, the proximal side refers to the side closer to the user in the direction of extension of the shaft 10, and the distal side refers to the side opposite the proximal side, i.e., the side to be treated. The extension direction of the shaft 10 is also referred to as the longitudinal axis direction. The longitudinal axis direction can also be referred to as the near-far direction. The radial direction refers to the radial direction of the shaft 10, and inward in the radial direction refers to the direction toward the center of the longitudinal axis of the shaft 10, and outward in the radial direction refers to the direction opposite to the inward. Note that in Figures 1 and 2, the right side of the figure is the proximal side, and the left side of the figure is the distal side.

[0027] First, a method for manufacturing the first electrode catheter 1 will be described.

[0028] The electrode catheter 1 is used, for example, for testing, treating, defibrillating, etc. for cardiac arrhythmia by passing the distal end of the electrode catheter 1 through the patient's blood vessels and reaching the heart.

[0029] The manufacturing method of the first electrode catheter 1 includes a preparation step of preparing a shaft 10 extending in the longitudinal direction and having an inner lumen, an electrode 20, and a conductor 30; a sharpening step of sharpening a first end 31 of the conductor 30; a hole forming step of inserting the first end 31 of the conductor 30 into the shaft 10 to form a hole 13 in the shaft 10 that connects the inner lumen to the outside; a conductor connection step of connecting the second end 32 of the conductor 30 to the electrode 20; and an electrode placement step of placing the electrode 20 outside the hole 13.

[0030] In the preparation step, a shaft 10 extending in the longitudinal direction and having a lumen, an electrode 20, and a lead wire 30 are prepared.

[0031] The shaft 10 may have a single lumen structure having one lumen, or a multi-lumen structure having multiple lumen. If the shaft 10 has one lumen, there are no partitions or the like inside the shaft 10 that separate the lumen, so the flexibility of the shaft 10 can be increased and the insertability of the electrode catheter 1 can be improved. If the shaft 10 has multiple lumens, multiple conductors 30, etc., to be placed in the lumens can be placed in different lumens, thereby preventing the conductors 30 from coming into contact with each other and preventing damage such as breakage of the conductors 30.

[0032] Examples of materials for the shaft 10 include synthetic resins such as polyolefin resins (e.g., polyethylene, polypropylene, etc.), polyamide resins (e.g., nylon, etc.), polyester resins (e.g., PET, etc.), aromatic polyetherketone resins (e.g., PEEK, etc.), polyetherpolyamide resins, polyurethane resins, polyimide resins, fluorine-containing resins (e.g., PTFE, PFA, ETFE, etc.), and polyvinyl chloride resins. The shaft 10 may have a single-layer structure or a multi-layer structure. For example, the shaft 10 may have a resin tube constituting the shaft 10, and the intermediate layer may be a metal braid (e.g., stainless steel, carbon steel, nickel-titanium alloy, etc.). The material for the shaft 10 is preferably a polyamide resin, and more preferably a polyamide elastomer. Using a polyamide elastomer for the shaft 10 provides a smooth outer surface and appropriate rigidity, resulting in an electrode catheter 1 that is easily insertable into a blood vessel.

[0033] A length appropriate for treatment can be selected as the length of the shaft 10 in the longitudinal direction. For example, the length of the shaft 10 in the longitudinal direction can be 500 mm or more and 1500 mm or less.

[0034] The outer diameter of the shaft 10 is preferably 0.5 mm or more, more preferably 0.7 mm or more, and even more preferably 1 mm or more. By setting the lower limit of the outer diameter of the shaft 10 within the above range, it is possible to impart appropriate rigidity to the shaft 10, resulting in an electrode catheter 1 that is easy to insert into blood vessels. Furthermore, the outer diameter of the shaft 10 is preferably 3 mm or less, more preferably 2.8 mm or less, and even more preferably 2.5 mm or less. By setting the upper limit of the outer diameter of the shaft 10 within the above range, it is possible to prevent the outer diameter of the electrode catheter 1 from becoming too large, thereby improving minimal invasiveness.

[0035] The thickness of the shaft 10 is preferably 50 μm or more, more preferably 100 μm or more, and even more preferably 150 μm or more. By setting the lower limit of the thickness of the shaft 10 within the above range, the rigidity of the shaft 10 can be increased, and the electrode catheter 1 can be made easy to insert into blood vessels. Furthermore, the thickness of the shaft 10 is preferably 350 μm or less, more preferably 300 μm or less, and even more preferably 250 μm or less. By setting the upper limit of the thickness of the shaft 10 within the above range, the lumen of the shaft 10 can be widened, and the electrodes 20 of the electrode catheter 1 can be made multipolar.

[0036] The electrode 20 may be a ring-shaped electrode or a flat electrode having a rectangular or square shape, for example. When the electrode 20 is a flat electrode, at least one of the back surface (inner surface) and the front surface (outer surface) of the flat electrode may be curved so as to easily fit along the curved surface of the shaft 10. In particular, the electrode 20 is preferably ring-shaped. When the electrode 20 is a ring-shaped electrode, the area of ​​the electrode 20 on the circumference of the shaft 10 can be increased, making it easier to bring the electrode 20 into contact with the target site, such as the inner wall of the heart.

[0037] Examples of materials constituting the electrode 20 include metal materials such as copper, gold, platinum, aluminum, iron, and alloys thereof. Among these, the material constituting the electrode 20 is preferably platinum or an alloy thereof. By configuring the electrode 20 in this manner, the contrast of the electrode 20 to X-rays can be improved, and the position of the electrode 20 can be confirmed by using X-rays when the electrode catheter 1 is in use.

[0038] It is preferable that there are multiple electrodes 20. When there are multiple electrodes 20, the electrodes 20 may be the same or different in size. The different sizes of the electrodes 20 refer to, for example, that the lengths of the electrodes 20 in the longitudinal axis direction of the shaft 10 are different.

[0039] The conductor 30 electrically connects the electrode 20 to an external device (not shown) such as a power supply for the electrode catheter 1, and is disposed in the lumen of the shaft 10. By connecting the conductor 30 to the external device of the electrode catheter 1, the electrode 20 and the external device of the electrode catheter 1 are electrically connected. Although not shown, the electrode catheter 1 may have a connector on the proximal side, and the conductor 30 may be connected to the connector, and the electrode 20 may be connected to the external device by connecting the connector to the external device of the electrode catheter 1.

[0040] Although not shown, the conductor 30 has a core and a coating. The material constituting the core of the conductor 30 may be any conductive material, such as iron, copper, silver, stainless steel, tungsten, nickel, titanium, or alloys thereof. Among these, stainless steel is preferably used as the material constituting the core of the conductor 30. Because stainless steel has straightness and rigidity, using stainless steel as the material constituting the core of the conductor 30 makes it easier to pass the conductor 30 through the lumen of the catheter shaft 10 during the manufacture of the electrode catheter 1, and also makes the conductor 30 less likely to break at the connection portion of the electrode 20, etc.

[0041] The coating of the conductor 30 is preferably present in portions other than the ends connected to other objects such as the electrode 20. Specifically, for example, the coating at the second end 32 of the conductor 30 can be partially removed and this portion can be welded to the electrode 20 to connect the second end 32 of the conductor 30 to the electrode 20, and the coating at the first end 31 of the conductor 30, which is connected to an external device of the electrode catheter 1 or a connector of the handle 50, can be partially removed, thereby allowing the conductor 30 to have a coating in portions other than the ends.

[0042] The coating of the conductor 30 may be made of any insulating material, such as polyolefin resins (e.g., polyethylene, polypropylene, etc.), polyamide resins (e.g., nylon, etc.), polyester resins (e.g., PET, etc.), aromatic polyetherketone resins (e.g., PEEK, etc.), polyetherpolyamide resins, polyurethane resins, polyimide resins, fluorine-based resins (e.g., PTFE, PFA, ETFE, etc.), and synthetic resins (e.g., polyvinyl chloride resins). The material constituting the coating of the conductor 30 is preferably a fluorine-based resin, and more preferably PFA. The fluorine-based resin coating of the conductor 30 enhances the insulation of the conductor 30 and improves the sliding properties of the conductor 30 relative to other objects, such as the conductor 30 connected to another electrode 20, in the lumen of the shaft 10, thereby preventing damage to the coating due to contact with other objects.

[0043] Figure 3 is an enlarged view of the first end 31 of the conductor 30 after sharpening. As shown in Figure 3, the sharpening step sharpens the first end 31 of the conductor 30. By sharpening the first end 31 of the conductor 30, it becomes easier for the first end 31 of the conductor 30 to pierce the shaft 10 in the hole forming step, and the hole 13 can be easily formed.

[0044] The sharpening of the first end 31 of the conductor 30 is a process for sharpening the first end 31 of the conductor 30. Specific examples of sharpening include cutting the first end 31 of the conductor 30 at an angle, polishing the first end 31 of the conductor 30 to sharpen it, applying pressure to the first end 31 of the conductor 30 to flatten it, and twisting and stranding multiple metal wires that form the core of the first end 31 of the conductor 30. Among these, the sharpening of the first end 31 of the conductor 30 is preferably performed by cutting the first end 31 of the conductor 30 at an angle. By performing sharpening by cutting the first end 31 of the conductor 30 at an angle, it is possible to easily sharpen the first end 31 of the conductor 30.

[0045] Figure 4 is a cross-sectional view taken along the longitudinal axis of the shaft 10 during the hole forming step. As shown in Figure 4, in the hole forming step, a first end 31 of a conducting wire 30 is pierced into the shaft 10 to form a hole 13 in the shaft 10 that connects the inner cavity with the outside. The hole forming step is performed after the sharpening step. In the hole forming step, the conducting wire 30 is pierced into the shaft 10 to form a hole 13 in the shaft 10, and the conducting wire 30 is passed through the inner cavity of the shaft 10.

[0046] By piercing the first end 31 of the sharpened conductor 30 into the shaft 10 to form the hole 13, the size of the hole 13 becomes close to the outer diameter of the conductor 30. As a result, it is possible to easily manufacture an electrode catheter 1 that is less likely to have a gap between the conductor 30 and the hole 13, and that is less likely to allow blood or other liquids to penetrate into the lumen of the shaft 10 through this gap. Note that the first end 31 of the conductor 30 is preferably the proximal end of the conductor 30.

[0047] The extending direction of the holes 13 may be perpendicular to the longitudinal axis direction as shown in FIG. 4, or may be oblique to the longitudinal axis direction, although not shown.

[0048] 5 is a cross-sectional view taken along the longitudinal axis of the shaft 10 during the conductor connecting step. As shown in FIG. 5, the conductor connecting step involves connecting the second end 32 of the conductor 30 to the electrode 20. Note that the second end 32 of the conductor 30 is preferably the distal end of the conductor 30.

[0049] The conductive wire 30 can be connected to the electrode 20 by, for example, welding, brazing such as soldering, or crimping. Among these, welding is preferred as the method for connecting the conductive wire 30 to the electrode 20. Connecting the conductive wire 30 to the electrode 20 by welding can increase the connection strength between the conductive wire 30 and the electrode 20. Although not shown, the conductive wire 30 and the electrode 20 may be connected via a conductive member having conductivity between them.

[0050] The connection between the conducting wire 30 and the electrode 20 may be coated with a resin or the like to prevent oxidation degradation due to moisture contained in the atmosphere, etc. Examples of resins used for this coating include polyurethane-based resins and epoxy-based resins.

[0051] The conductor wire connecting step may be performed before or after the hole forming step. Performing the conductor wire connecting step before the hole forming step makes it easier to connect the conductor wire 30 to the electrode 20 by welding or the like. Performing the conductor wire connecting step after the hole forming step makes it easier to handle the conductor wire 30 and to form the hole 13 by piercing the conductor wire 30 into the shaft 10.

[0052] Fig. 6 is a cross-sectional view taken along the longitudinal axis of the shaft 10 during the electrode placement step. As shown in Fig. 6, in the electrode placement step, the electrode 20 is placed outside the hole 13. The electrode placement step is preferably performed after the conductor connection step.

[0053] The electrode 20 is preferably disposed on the outer surface of the shaft 10. By disposing the electrode 20 on the shaft 10, it becomes possible to measure the intracardiac potential by bringing the electrode 20 close to or in contact with the inner wall of the heart, thereby identifying an abnormal part of the heart that is causing arrhythmia, and performing defibrillation within the cardiac chamber.

[0054] 1 and 2, the electrode catheter 1 may have a distal tip 60 at the distal end of the shaft 10. When the electrode catheter 1 has the distal tip 60 at the distal end of the shaft 10, a distal tip positioning step of positioning the distal tip 60 at the distal end of the shaft 10 may be included.

[0055] Examples of the distal tip 60 include a hemispherical electrode and a lid-like member that prevents the opening of the distal end of the shaft 10. Having the distal tip 60 at the distal end of the shaft 10 makes it possible to prevent liquids such as blood from entering the lumen of the shaft 10 from the distal end of the shaft 10 when the electrode catheter 1 is in use. In addition, the distal tip 60 acts as a guide for the tip of the electrode catheter 1, making it possible to improve the insertability of the electrode catheter 1.

[0056] The material constituting the distal tip 60 may be, for example, the material constituting the shaft 10 or the material constituting the electrode 20. Note that the distal tip 60 may also serve as the electrode 20 by forming the distal tip 60 from a conductive material such as the material constituting the electrode 20 and connecting the distal tip 60 to the conductor 30.

[0057] 2, when the electrode catheter 1 has a distal tip 60 at the distal end of the shaft 10, the distal tip 60 has a distal tip connecting member 61 connected to it, and the distal tip connecting member 61 is preferably disposed in the lumen of the shaft 10. Examples of the distal tip connecting member 61 include a pull wire for bending the distal side of the shaft 10 and a lead wire 30 for allowing the distal tip 60 to function as the electrode 20.

[0058] When the distal tip 60 has a distal tip connecting member 61, the connecting member connecting step of connecting the distal tip connecting member 61 to the distal tip 60 may be performed after the distal tip positioning step, but is preferably performed before the distal tip positioning step. By performing the connecting member connecting step before the distal tip positioning step, it becomes easier to connect the distal tip connecting member 61 to the distal tip 60, and it becomes easier to reliably fix the distal tip connecting member 61 to the distal tip 60.

[0059] Although not shown, the electrode catheter 1 does not have to have a distal tip 60 at the distal end of the shaft 10. If the electrode catheter 1 does not have a distal tip 60, it is preferable to include a step of sealing the opening at the distal end of the shaft 10 by heat sealing the distal end of the shaft 10 or the like.

[0060] As shown in Fig. 3, the sharpening step preferably involves cutting first end 31 of conductor 30 so that first end 31 of conductor 30 has an acute angle. Sharing first end 31 of conductor 30 with an acute angle means that first end 31 of conductor 30 has a portion where angle θ is greater than 0 degrees and less than 90 degrees, as shown in Fig. 3. By cutting first end 31 of conductor 30 with an acute angle in the sharpening step, first end 31 of conductor 30 can be made to be easier to pierce into shaft 10, making the hole forming step easier.

[0061] After sharpening, the first end 31 of the conductor 30 preferably has a portion where the angle θ is 80 degrees or less, more preferably 70 degrees or less, and even more preferably 60 degrees or less. By setting the upper limit of the angle θ of the first end 31 of the conductor 30 after sharpening within the above range, it becomes easier to pierce the first end 31 of the conductor 30 into the shaft 10 and form the hole 13. Furthermore, after sharpening, the first end 31 of the conductor 30 preferably has a portion where the angle θ is 10 degrees or more, more preferably 15 degrees or more, and even more preferably 20 degrees or more. By setting the lower limit of the angle θ of the first end 31 of the conductor 30 after sharpening within the above range, it becomes possible to impart appropriate rigidity to the first end 31 of the conductor 30, making it easier to pierce the first end 31 of the conductor 30 into the shaft 10.

[0062] It is preferable to have a conductor heating step of heating first end 31 of conductor 30 before the hole forming step. By heating first end 31 of conductor 30 and then piercing first end 31 of conductor 30 into shaft 10 to form hole 13, the heat from first end 31 of conductor 30 is transferred to the tube wall of shaft 10, softening the resin that makes up shaft 10. As a result, it becomes easier for first end 31 of conductor 30 to pierce the tube wall of shaft 10, making it easier to form hole 13 in shaft 10.

[0063] In the conductor heating step, the heating temperature of first end 31 of conductor 30 is preferably higher than the melting point of the resin that constitutes shaft 10. By heating first end 31 of conductor 30 to a temperature higher than the melting point of the resin that constitutes shaft 10, first end 31 of conductor 30 can be easily pierced into the tube wall of shaft 10 in the hole forming step, making it easier to form hole 13 in shaft 10.

[0064] Next, we will explain the method for manufacturing the second electrode catheter 1. In the following explanation, parts that overlap with the above explanation will be omitted.

[0065] The manufacturing method of the second electrode catheter 1 includes a preparation step of preparing a shaft 10 extending in the longitudinal direction and having an inner lumen, an electrode 20, and a conductor 30; a conductor heating step of heating a first end 31 of the conductor 30; a hole forming step of inserting the first end 31 of the conductor 30 into the shaft 10 to form a hole 13 in the shaft 10 that connects the inner lumen to the outside; a conductor connecting step of connecting the second end 32 of the conductor 30 to the electrode 20; and an electrode placement step of placing the electrode 20 outside the hole 13.

[0066] By including the conductor heating step and the hole forming step, it becomes easier to pierce the first end 31 of the conductor 30 into the shaft 10, and to drill the hole 13 in the shaft 10. Therefore, it is possible to improve the manufacturing efficiency of the electrode catheter 1.

[0067] It is preferable to have a sharpening step of sharpening the first end 31 of the conductor 30 before the hole forming step. By sharpening the first end 31 of the conductor 30, the first end 31 of the conductor 30 becomes easier to pierce into the shaft 10, and it becomes possible to easily form the hole 13 in the hole forming step.

[0068] In the manufacturing method of the electrode catheter 1 of the present invention, it is preferable to include a step of exposing the first end 31 of the conductor 30 from the proximal end of the shaft 10 after the hole forming step. By exposing the first end 31 of the conductor 30 from the proximal end of the shaft 10, it becomes easier to attach a member to the conductor 30 for electrically connecting the electrode catheter 1 to an external device such as a power supply unit.

[0069] Although not shown, it is preferable to include a wire cutting step of cutting the first end 31 of the conductor 30 after the hole forming step. By including at least one of the sharpening step and the conductor heating step, the surface condition, thickness, etc. of the first end 31 of the conductor 30 may vary along the length or circumference of the conductor 30. Furthermore, because the first end 31 of the conductor 30 is pierced into the shaft 10 to form the hole 13, the first end 31 of the conductor 30 may be bent or broken. By including a wire cutting step of cutting the first end 31 of the conductor 30 after the hole forming step, it is possible to remove any altered first end 31 of the conductor 30, which makes it easier to perform, for example, a step of connecting the end of the conductor 30 on the side of the first end 31 to an external device.

[0070] The conductor cutting step is preferably performed after the step of exposing first end 31 of conductor 30 from the proximal end of shaft 10. By cutting first end 31 of conductor 30 after exposing first end 31 of conductor 30 from the proximal end of shaft 10, the conductor cutting step becomes easier to perform, and the amount of conductor 30 to be cut can be more easily adjusted.

[0071] 6, after the electrode placement step, the second end 32 of the conductor 30 is preferably located outside the shaft 10. "The second end 32 of the conductor 30 being located outside the shaft 10" can be said to mean that the second end 32 of the conductor 30 is not located in the lumen of the shaft 10. By having the second end 32 of the conductor 30 located outside the shaft 10, the surface area of ​​the conductor 30 that is inserted through the vascular wall of the shaft 10 can be reduced. As a result, the number of holes 13 for inserting the conductor 30 into the lumen of the shaft 10 can be reduced, and the size of the holes 13 can be made smaller, thereby reducing the number of paths for fluids such as blood to enter the lumen of the shaft 10. Furthermore, for example, if the connection between the conductor 30 and the electrode 20 is made by welding and the distance between the welded point between the conductor 30 and the electrode 20 and the second end 32 of the conductor 30 is short, since the second end 32 of the conductor 30 is located outside the shaft 10, the distance between the welded point between the conductor 30 and the electrode 20 and the hole 13 can be increased, preventing the welded point between the conductor 30 and the electrode 20 from pushing open the hole 13 and creating a gap.

[0072] Although not shown, it is preferable to have a wire bonding step of fixing the wire 30 to the hole 13 with an adhesive after the hole forming step. By fixing the wire 30 to the hole 13 with an adhesive, the adhesive is present between the hole 13 and the wire 30, making it even less likely that a gap will form between the hole 13 and the wire 30. Furthermore, by firmly fixing the wire 30 to the hole 13 with an adhesive, when a load is applied to the wire 30, for example, when the shaft 10 of the electrode catheter 1 is bent and the wire 30 is pulled, the wire 30 is prevented from being applied to the hole 13 by the wire 30 and causing the hole 13 to tear.

[0073] The adhesive for adhesively fixing the conductive wire 30 in the hole 13 is preferably a polyurethane-based, epoxy-based, cyano-based, fluorine-based, or silicone-based adhesive.

[0074] As described above, the first method for manufacturing an electrode catheter of the present invention includes the following steps: a preparation step of preparing a shaft extending in the longitudinal direction and having a lumen, an electrode, and a lead wire; a sharpening step of sharpening the first end of the lead wire; a hole forming step of inserting the first end of the lead wire into the shaft to form a hole in the shaft that connects the lumen to the outside; a lead wire connecting step of connecting the second end of the lead wire to the electrode; and an electrode positioning step of positioning the electrode outside the hole. Also, the second method for manufacturing an electrode catheter of the present invention includes the following steps: a preparation step of preparing a shaft extending in the longitudinal direction and having a lumen, an electrode, and a lead wire; a lead wire heating step of heating the first end of the lead wire; a hole forming step of inserting the first end of the lead wire into the shaft to form a hole in the shaft that connects the lumen to the outside; a lead wire connecting step of connecting the second end of the lead wire to the electrode; and an electrode positioning step of positioning the electrode outside the hole. By including these steps in the manufacturing method of the electrode catheter of the present invention, holes that are less likely to create gaps between the shaft and the conductor can be easily formed in the shaft, thereby improving the manufacturing efficiency of electrode catheters that are less likely to allow liquids such as blood to penetrate into the inner cavity of the shaft. [Explanation of symbols]

[0075] 1: Electrode catheter 10: Shaft 13: Hole 20: Electrode 30: Conductor 31: 1st end 32: 2nd end 50: Handle 60: Tip 61: Tip tip connecting member

Claims

1. a preparing step of providing a shaft extending in a longitudinal direction and having a lumen, an electrode, and a lead; a sharpening step of sharpening a first end of the conductive wire; a hole forming step of inserting the first end of the conductive wire into the shaft to form a hole in the shaft that connects the inner cavity to the outside; a wire connecting step of connecting a second end of the wire to the electrode; and an electrode placement step of placing the electrode outside the hole.

2. The sharpening step is performed by cutting the conductive wire, The method for manufacturing an electrode catheter according to claim 1, wherein the first end of the conductive wire is formed into an acute angle after the sharpening step.

3. 3. The method for manufacturing an electrode catheter according to claim 1, further comprising a conductor heating step of heating the first end of the conductor before the hole forming step.

4. a preparing step of providing a shaft extending in a longitudinal direction and having a lumen, an electrode, and a lead; a conductor heating step of heating a first end of the conductor; a hole forming step of inserting the first end of the conductive wire into the shaft to form a hole in the shaft that connects the inner cavity to the outside; a wire connecting step of connecting a second end of the wire to the electrode; and an electrode placement step of placing the electrode outside the hole.

5. 5. The method for manufacturing an electrode catheter according to claim 4, further comprising a sharpening step of sharpening the first end of the conductor wire before the hole forming step.

6. A method for manufacturing an electrode catheter according to any one of claims 1 to 5, further comprising a wire cutting step of cutting the wire so as to remove any altered portion of the wire after the hole forming step.

7. 7. The method for manufacturing an electrode catheter according to claim 1, wherein after the electrode placement step, the second end of the conductive wire is located outside the shaft.

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