Electrode catheter

Abstract

To provide an electrode catheter capable of suppressing coming off of a conductor wire from a conductor wire hole, and capable of being easily produced.SOLUTION: There is provided an electrode catheter 1 comprising: a shaft 10 which extends in a longitudinal axis direction, has a lumen, and has a slit 40 in which the lumen communicates with an external surface; an electrode 20 arranged outside of the slit 40; and a conductor wire 30 which is connected to the electrode 20 and extends into the lumen of the shaft 10 through the slit 40, where in a cross section along the longitudinal axis direction of the shaft 10, the slit 40 has a part which is oblique with respect to a radial direction of the shaft 10.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] For example, Patent Document 1 describes a method for manufacturing an electrode catheter, which includes step A of preparing a cylindrical body having an opening on the side, step B of connecting a conductive member and a lead wire, step C of arranging the lead wire inside the cylindrical body and arranging the conductive member in the opening, step D of arranging a ring electrode outside the opening, and step E of crimping the ring electrode to block at least a portion of the opening with the conductive member.

[0004] Patent document 2 describes an electrode catheter having a cylindrical body, a conductor having a first section, a second section, and a third section in that order, and a ring electrode arranged on the outside of the cylindrical body, wherein the first and third sections of the conductor are arranged inside the cylindrical body, the second section of the conductor is exposed on the side of the cylindrical body, and at least a portion of the second section of the conductor is connected to the ring electrode.

[0005] Patent Document 3 describes a manufacturing method characterized by including the steps of: welding a lead wire to the inside of an electrode in advance, inserting the lead wire into the inner lumen of an outer tube through a hole, and attaching the electrode to the outer tube; inserting a mandrel into the inner lumen of the outer tube with the electrode attached; applying pressure to the outer tube in the central axis direction from the outer periphery to remove any steps between the electrode surface and the outer periphery of the catheter outer tube; removing the mandrel from the outer tube; inserting the lead wire into the inner lumen of the operating tube; welding the operating tube to a double tube consisting of the outer tube and an inner tube for inserting a guide wire to form a guide wire insertion port; and connecting a terminal for monitoring the electrode potential to each of the lead wires connected to the electrode. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-137019 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-137020 [Patent Document 3] JP 2017-176200 A Summary of the Invention [Problem to be solved by the invention]

[0007] In the electrode catheters of Patent Documents 1 to 3, when the lead wire connected to the electrode is inserted into the lead wire hole provided on the side of the shaft, the lead wire is prone to movement and may become dislodged from the lead wire hole. Therefore, after inserting the lead wire into the lead wire hole, it is necessary to immediately connect the lead wire to the electrode and position the electrode on the shaft, or to temporarily fasten the lead wire, leaving room for improvement in order to increase the manufacturing efficiency of electrode catheters.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an electrode catheter in which the lead wire is less likely to come out of the lead wire hole and which is easy to manufacture. [Means for solving the problem]

[0009] The first electrode catheter that was able to solve the above problem comprises a shaft that extends in the longitudinal direction, has an inner lumen, and has a slit that connects the inner lumen to the outer surface, an electrode that is positioned outside the slit, and a conducting wire that is connected to the electrode and extends into the inner lumen of the shaft through the slit, and in a cross section along the longitudinal direction of the shaft, the slit has a portion that is oblique to the radial direction of the shaft.

[0010] In the electrode catheter of the present invention, it is preferable that, in a cross section along the longitudinal axis of the shaft, the slit has a portion where the angle between the longitudinal axis of the shaft and the extending direction of the slit is 10 degrees or more and 80 degrees or less.

[0011] In the electrode catheter of the present invention, the slit preferably has a bent portion in a cross section along the longitudinal axis of the shaft.

[0012] The second electrode catheter that was able to solve the above problem comprises a shaft that extends in the longitudinal direction, has an inner lumen, and has a slit that connects the inner lumen to the outer surface, an electrode that is positioned outside the slit, and a conducting wire that is connected to the electrode and extends into the inner lumen of the shaft through the slit, and in a cross section perpendicular to the longitudinal direction of the shaft, the slit has a portion that is oblique to the radial direction of the shaft.

[0013] In the electrode catheter of the present invention, it is preferable that, in a cross section perpendicular to the longitudinal axis direction of the shaft, the slit has a portion where the angle between a perpendicular line passing through the center point of the shaft and the extension direction of the slit is 10 degrees or more and 80 degrees or less.

[0014] In the electrode catheter of the present invention, the slit preferably has a bent portion in a cross section perpendicular to the longitudinal axis direction of the shaft. [Effects of the Invention]

[0015] According to the electrode catheter of the present invention, the slit has a portion that is oblique to the radial direction of the shaft in a cross section along the longitudinal axis of the shaft or in a cross section perpendicular to the longitudinal axis, so that the conductor inserted in the slit is easily caught in the slit, making it difficult for the conductor to come out of the slit, and making the electrode catheter easy to manufacture. [Brief explanation of the drawings]

[0016] [Figure 1] 1 shows an overall view of an electrode catheter according to one embodiment of the present invention. [Figure 2] 1 illustrates a longitudinal cross-sectional view of an electrode catheter according to one embodiment of the present invention. [Figure 3] 10 shows a longitudinal cross-sectional view of an electrode catheter according to another embodiment of the present invention. [Figure 4] 1A-1C show cross-sectional views perpendicular to the longitudinal axis of electrode catheters according to different embodiments of the present invention. [Figure 5] 10 is a cross-sectional view perpendicular to the longitudinal axis of an electrode catheter according to yet another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] 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.

[0018] 1 is an overall view of an electrode catheter 1 according to one embodiment of the present invention. The electrode catheter 1 is used, for example, for testing, treating, and defibrillating cardiac arrhythmias by passing the distal end of the electrode catheter 1 through the patient's blood vessels to reach the heart.

[0019] 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. In addition, in Figure 1, the right side of the figure is the proximal side, and the left side of the figure is the distal side.

[0020] First, the first electrode catheter 1 will be described.

[0021] As shown in Figure 1, the electrode catheter 1 has a shaft 10 that extends in the longitudinal direction, has an inner lumen, and has a slit 40 that connects the inner lumen to the outer surface, an electrode 20 that is positioned outside the slit 40, and a conductive wire 30 that is connected to the electrode 20 and extends into the inner lumen of the shaft 10 through the slit 40.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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, different lengths of the electrodes 20 in the longitudinal axis direction of the shaft 10.

[0031] 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.

[0032] 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 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.

[0033] The coating of the lead wire 30 is preferably present in a portion other than both ends that are connected to other objects such as the electrode 20. Specifically, for example, the distal end of the lead wire 30 can be connected to the electrode 20 by removing a portion of the coating at the distal end of the lead wire 30 and welding this portion to the electrode 20, and the proximal end of the lead wire 30 that is connected to an external device of the electrode catheter 1 or a connector of the handle 50 can be removed a portion of the coating, thereby allowing the lead wire 30 to be configured to have a coating in a portion other than both ends.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 2 and 3 are cross-sectional views taken along the longitudinal axis of the electrode catheter 1. As shown in FIGS. 2 and 3, in a cross-section taken along the longitudinal axis of the shaft 10, the slit 40 has a portion that is oblique to the radial direction of the shaft 10. The slit 40 is for inserting the conducting wire 30 from the outside of the shaft 10 into the lumen of the shaft 10. Note that, hereinafter, the "portion that is oblique to the radial direction of the shaft 10" may be referred to as the "oblique portion."

[0038] The radial direction of the shaft 10 can also be said to be the thickness direction of the tube wall of the shaft 10. In addition, in Figures 2 and 3, the vertical direction of the drawings is the radial direction of the shaft 10.

[0039] In a cross section along the longitudinal axis of the shaft 10, the slit 40 has a portion that is oblique to the radial direction of the shaft 10, so that the conductor 30 is likely to get caught on the end of this oblique portion. Therefore, when a load in the longitudinal axis direction of the shaft 10 is unintentionally applied to the conductor 30 inserted through the slit 40, the conductor 30 is less likely to come out of the slit 40, making it easier to manufacture the electrode catheter 1 and improving manufacturing efficiency.

[0040] To make a shaft 10 having a slit 40 with an oblique portion in a cross section along the longitudinal axis of the shaft 10, for example, a cutting tool such as a knife or cutter, or a drill or punch can be used to make an incision in the tubular wall of the shaft 10 by inserting the tool at an angle to the thickness direction of the tubular wall of the shaft 10.

[0041] Specific shapes of the slit 40 having an oblique portion in a cross section along the longitudinal axis direction of the shaft 10 include, for example, a configuration in which the opening of the slit 40 on the outer surface side of the shaft 10 is located proximal to the opening of the slit 40 on the inner cavity side of the shaft 10 as shown in Fig. 2, a configuration in which the opening of the slit 40 on the outer surface side of the shaft 10 is located distal to the opening of the slit 40 on the inner cavity side of the shaft 10 (not shown), and a configuration in which the slit 40 has a bent portion as shown in Fig. 3. Details of the configuration in which the slit 40 has a bent portion will be described later.

[0042] In a cross section taken along the longitudinal axis of the shaft 10, the slit 40 may be oblique throughout the entire length from the opening on the outer surface side of the shaft 10 to the opening on the inner lumen side of the shaft 10, or may be partially oblique. A configuration in which the slit 40 is partially oblique from the opening on the outer surface side of the shaft 10 to the opening on the inner lumen side means that the slit 40 has an oblique portion and a portion that runs along the thickness direction of the tube wall of the shaft 10. In particular, it is preferable that the slit 40 be oblique throughout the entire length from the opening on the outer surface side of the shaft 10 to the opening on the inner lumen side. By making the slit 40 entirely oblique, the conducting wire 30 inserted through the slit 40 can easily come into contact with the slit 40, thereby enhancing the effect of preventing the conducting wire 30 from slipping out of the slit 40.

[0043] The number of slits 40 in the shaft 10 may be one, but preferably is multiple. By having multiple slits 40 in the shaft 10, the electrode catheter 1 can be made to have multiple electrodes 20.

[0044] The extending direction of the slits 40 as viewed from the top surface of the slits 40 may be curved, wavy, zigzag, or the like, but is preferably linear. The linear extending direction of the slits 40 makes it easier to form the slits 40 in the shaft 10.

[0045] 2 and 3, in a cross section taken along the longitudinal axis of the shaft 10, the slit 40 preferably has a portion where the angle θ1 between the longitudinal axis of the shaft 10 and the extension direction of the slit 40 is 10 degrees or more and 80 degrees or less. When the slit 40 has a portion where the angle θ1 between the longitudinal axis of the shaft 10 and the extension direction of the slit 40 is 10 degrees or more and 80 degrees or less, the conducting wire 30 inserted through the slit 40 and the slit 40 are more likely to come into contact with each other. As a result, during the manufacture of the electrode catheter 1, the conducting wire 30 inserted through the slit 40 is less likely to come out of the slit 40.

[0046] In a cross section taken along the longitudinal axis of the shaft 10, the angle θ1 between the longitudinal axis of the shaft 10 and the extension direction of the slit 40 is preferably 10 degrees or more, more preferably 15 degrees or more, and even more preferably 20 degrees or more for at least a portion of the slit 40. By setting the lower limit of the angle θ1 between the longitudinal axis of the shaft 10 and the extension direction of the slit 40 within the above range, the conductive wire 30 can be easily inserted into the slit 40, thereby improving the manufacturing efficiency of the electrode catheter 1. Furthermore, in a cross section taken along the longitudinal axis of the shaft 10, the angle θ1 between the longitudinal axis of the shaft 10 and the extension direction of the slit 40 is preferably 80 degrees or less, more preferably 75 degrees or less, and even more preferably 70 degrees or less for at least a portion of the slit 40. By setting the upper limit of the angle θ1 between the longitudinal axis of the shaft 10 and the extension direction of the slit 40 within the above range, the conductive wire 30 can be more easily caught in the slit 40 and less likely to come out.

[0047] As shown in Fig. 3, the slit 40 preferably has a bent portion in a cross section taken along the longitudinal axis of the shaft 10. The bent portion refers to a portion where the angle θ1 between the longitudinal axis of the shaft 10 and the extension direction of the slit 40 changes. When the slit 40 has a bent portion in a cross section taken along the longitudinal axis of the shaft 10, the conducting wire 30 inserted through the slit 40 gets caught on the bent portion, causing friction between the conducting wire 30 and the slit 40. As a result, the conducting wire 30 can be made less likely to come out of the slit 40.

[0048] Specific shapes of the slit 40 having a bent portion in a cross section along the longitudinal axis of the shaft 10 include, for example, a configuration as shown in Figure 3, in which the middle part of the slit 40 is located distal to the opening of the slit 40 on the outer surface side of the shaft 10 and the opening of the slit 40 on the inner cavity side of the shaft 10, forming a dogleg shape, and a configuration (not shown) in which the middle part of the slit 40 is located proximal to the opening of the slit 40 on the outer surface side of the shaft 10 and the opening of the slit 40 on the inner cavity side of the shaft 10, forming an inverted dogleg shape.

[0049] To create a slit 40 having a bent portion in a cross section along the longitudinal axis of shaft 10, for example, a cutting tool such as a knife or cutter can be used to make an incision in the tubular wall of shaft 10 from the outer surface of shaft 10, and then the cutting tool can be inserted into the inner cavity of shaft 10 and a further incision can be made in the tubular wall of shaft 10 from the inner surface of shaft 10 toward the incision made from the outer surface of shaft 10.

[0050] When the electrode 20 is a ring-shaped electrode, the inner diameter of the electrode 20 is preferably smaller than the outer diameter of the shaft 10. By making the inner diameter of the electrode 20 smaller than the outer diameter of the shaft 10, the end of the electrode 20 is less likely to get caught on other objects, and it is less likely to damage the inner walls of blood vessels or the heart. To make the inner diameter of the electrode 20 smaller than the outer diameter of the shaft 10, for example, there are methods such as forming the inner diameter of the electrode 20 larger than the outer diameter of the shaft 10, passing the electrode 20 through the shaft 10, and crimping the electrode 20 from the outside to reduce the inner diameter of the electrode 20, or forming the shaft 10 from a thermally expandable resin so that the outer diameter of the electrode 20 is smaller than the inner diameter of the electrode 20, passing the electrode 20 through the shaft 10, and heating the shaft 10 to increase the outer diameter of the shaft 10.

[0051] 1, the electrode catheter 1 may have a handle 50 on the proximal side. When the electrode catheter 1 has the handle 50, the electrode catheter 1 can be easily manipulated.

[0052] As shown in FIGS. 1 to 3, the electrode catheter 1 may have a distal tip 60 at the distal end of the shaft 10.

[0053] 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.

[0054] 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.

[0055] 2 and 3, 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.

[0056] 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 that the distal end of the shaft 10 is heat-sealed or the like to seal the opening at the distal end of the shaft 10.

[0057] As shown in FIGS. 2 and 3 , the distal end 32 of the conductor 30 is preferably located outside the shaft 10. The distal end 32 of the conductor 30 being located outside the shaft 10 can be said to be not located in the lumen of the shaft 10. Having the distal end 32 of the conductor 30 located outside the shaft 10 reduces the likelihood of a gap being formed between the conductor 30 passing through the slit 40 and the slit 40, thereby making it more difficult for liquids such as blood to penetrate into the lumen of the shaft 10. Furthermore, for example, if the connection between the conductor 30 and the electrode 20 is performed by welding and the welded portion between the conductor 30 and the electrode 20 is close to the distal end 32 of the conductor 30, having the distal end 32 of the conductor 30 located outside the shaft 10 can increase the distance between the welded portion between the conductor 30 and the electrode 20 and the slit 40, preventing the welded portion between the conductor 30 and the electrode 20 from widening the slit 40 and creating a gap.

[0058] Although not shown, the conductor 30 is preferably fixed to the slit 40 with an adhesive. By fixing the conductor 30 to the slit 40 with an adhesive, the conductor 30 is firmly fixed to the slit 40. Therefore, the electrode catheter 1 can be made such that the conductor 30 is less likely to come out of the slit 40.

[0059] The adhesive for adhering and fixing the conductive wire 30 to the slit 40 is preferably a polyurethane-based, epoxy-based, cyano-based, fluorine-based, or silicone-based adhesive.

[0060] Next, we will explain the second electrode catheter 1. In the following explanation, parts that overlap with the above explanation will be omitted.

[0061] 4 and 5 are cross-sectional views perpendicular to the longitudinal axis direction of the electrode catheter 1. As shown in Fig. 4 and Fig. 5, in the cross-section perpendicular to the longitudinal axis direction of the shaft 10, the slit 40 has a portion that is oblique to the radial direction of the shaft 10.

[0062] In a cross section perpendicular to the longitudinal axis of the shaft 10, the slit 40 has a portion that is oblique to the radial direction of the shaft 10, so that the conducting wire 30 inserted through the slit 40 is likely to get caught in the oblique portion, and friction occurs between the conducting wire 30 and the slit 40, making it difficult for the conducting wire 30 to come out of the slit 40. As a result, the manufacturing efficiency of the electrode catheter 1 can be improved.

[0063] To make a shaft 10 having a slit 40 with an oblique portion in a cross section perpendicular to the longitudinal axis direction of the shaft 10, similar to the example of the method for making a shaft 10 with a slit 40 with an oblique portion in a cross section along the longitudinal axis direction of the shaft 10 described above, an incision can be made in the tubular wall of the shaft 10 using a cutting tool such as a knife or cutter, or a drill or punch, and inserting the tool at an angle to the thickness direction of the tubular wall of the shaft 10.

[0064] Specific shapes of the slit 40 having an oblique portion in a cross section perpendicular to the longitudinal axis direction of the shaft 10 include, for example, a configuration in which the opening of the slit 40 on the outer surface side of the shaft 10 is on one side (the left side of the figure) of the opening of the slit 40 on the inner cavity side of the shaft 10, as shown in Fig. 4, a configuration in which the opening of the slit 40 on the outer surface side of the shaft 10 is on the other side (the right side of the figure) of the opening of the slit 40 on the inner cavity side of the shaft 10, although not shown, and a configuration in which the slit 40 has a bent portion as shown in Fig. 5. Details of the configuration in which the slit 40 has a bent portion will be described later.

[0065] In a cross section perpendicular to the longitudinal axis direction of shaft 10, slit 40 may be an oblique portion over the entire length from the opening on the outer surface side of shaft 10 to the opening on the inner cavity side of shaft 10, or may be an oblique portion only partially. In particular, slit 40 is preferably an oblique portion over the entire length from the opening on the outer surface side of shaft 10 to the opening on the inner cavity side. By making slit 40 an oblique portion over the entire length, the conducting wire 30 inserted through slit 40 can easily come into contact with slit 40, making it more difficult for conducting wire 30 to come out of slit 40.

[0066] 4 and 5, in a cross section perpendicular to the longitudinal axis direction of the shaft 10, the slit 40 preferably has a portion where the angle θ2 between the perpendicular line PL passing through the center point of the shaft 10 and the extension direction of the slit 40 is 10 degrees or more and 80 degrees or less. When the slit 40 has a portion where the angle θ2 between the perpendicular line PL passing through the center point of the shaft 10 and the extension direction of the slit 40 is 10 degrees or more and 80 degrees or less, the slit 40 and the conducting wire 30 inserted therein are more likely to come into contact with each other, and during the manufacture of the electrode catheter 1, the conducting wire 30 inserted therein is less likely to come out of the slit 40, thereby improving manufacturing efficiency.

[0067] In a cross section perpendicular to the longitudinal axis direction of the shaft 10, for at least a portion of the slit 40, the angle θ2 formed between the perpendicular line PL passing through the center point of the shaft 10 and the extension direction of the slit 40 is preferably 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 θ2 formed between the perpendicular line PL passing through the center point of the shaft 10 and the extension direction of the slit 40 within the above range, it is possible to easily insert the conducting wire 30 into the slit 40, thereby improving the manufacturing efficiency of the electrode catheter 1. Furthermore, in a cross section perpendicular to the longitudinal axis direction of the shaft 10, for at least a portion of the slit 40, the angle θ2 formed between the perpendicular line PL passing through the center point of the shaft 10 and the extension direction of the slit 40 is preferably 80 degrees or less, more preferably 75 degrees or less, and even more preferably 70 degrees or less. By setting the upper limit value of the angle θ2 between the perpendicular line PL passing through the center point of the shaft 10 and the extension direction of the slit 40 within the above range, the conductive wire 30 becomes more likely to be caught in the slit 40, thereby enhancing the effect of making it less likely for the conductive wire 30 to come out of the slit 40.

[0068] 5, the slit 40 preferably has a bent portion in a cross section perpendicular to the longitudinal axis direction of the shaft 10. The bent portion refers to a portion where the angle θ2 between a perpendicular line PL passing through the center point of the shaft 10 and the extension direction of the slit 40 changes. By having the slit 40 have a bent portion in a cross section perpendicular to the longitudinal axis direction of the shaft 10, the conducting wire 30 inserted through the slit 40 can be more easily caught in the bent portion, thereby improving the effect of making it less likely for the conducting wire 30 to come out of the slit 40.

[0069] Specific shapes of the slit 40 having a bent portion in a cross section perpendicular to the longitudinal axis direction of the shaft 10 include, for example, a configuration as shown in Figure 5, in which the middle part of the slit 40 is located on one side (left side of the figure) of the opening of the slit 40 on the outer surface side of the shaft 10 and the opening of the slit 40 on the inner cavity side of the shaft 10, forming a dogleg shape, and a configuration (not shown) in which the middle part of the slit 40 is located on the other side (right side of the figure) of the opening of the slit 40 on the outer surface side of the shaft 10 and the opening of the slit 40 on the inner cavity side of the shaft 10, forming an inverted dogleg shape.

[0070] To form a slit 40 having a bent portion in a cross section perpendicular to the longitudinal axis direction of shaft 10, similar to the example of a method for forming a slit 40 having a bent portion in a cross section along the longitudinal axis direction of shaft 10 described above, an incision can be made in the tubular wall of shaft 10 from the outer surface of shaft 10 using a blade such as a knife or cutter, and then the blade can be inserted into the inner cavity of shaft 10 and a further incision can be made in the tubular wall of shaft 10 from the inner surface of shaft 10 toward the incision made from the outer surface side of shaft 10.

[0071] As described above, the first electrode catheter of the present invention comprises a shaft extending in the longitudinal direction, having a lumen, and having a slit connecting the lumen to its outer surface, an electrode disposed outside the slit, and a conductor connected to the electrode and extending through the slit into the lumen of the shaft, wherein the slit has a portion oblique to the radial direction of the shaft in a cross section taken along the longitudinal direction of the shaft. The second electrode catheter of the present invention comprises a shaft extending in the longitudinal direction, having a lumen, and having a slit connecting the lumen to its outer surface, an electrode disposed outside the slit, and a conductor connected to the electrode and extending through the slit into the lumen of the shaft, wherein the slit has a portion oblique to the radial direction of the shaft in a cross section perpendicular to the longitudinal direction of the shaft. This configuration of the electrode catheter of the present invention makes it easier for the conductor inserted through the slit to get caught in the slit and less likely to slip out of the slit, resulting in an electrode catheter that is easy to manufacture. [Explanation of symbols]

[0072] 1: Electrode catheter 10: Shaft 20: Electrode 30: Conductor 32: Distal end 40: Slit 50: Handle 60: Tip 61: Tip tip connecting member PL: Perpendicular line passing through the center point of the shaft θ1: Angle between the extension direction of the slit and the longitudinal direction of the shaft θ2: The angle between the perpendicular line passing through the center point of the shaft and the extension direction of the slit

Claims

1. a shaft extending in a longitudinal direction, having an inner cavity, and having a slit communicating between the inner cavity and an outer surface; an electrode disposed outside the slit; a conductive wire connected to the electrode and extending through the slit into the lumen of the shaft; An electrode catheter in which, in a cross section along the longitudinal axis of the shaft, the slit has a portion that is oblique to the radial direction of the shaft, and the slit extends from the proximal side to the distal side as it progresses from the outer side to the inner side in the radial direction of the shaft.

2. 2. The electrode catheter according to claim 1, wherein in a cross section along the longitudinal axis of the shaft, the slit has a portion where the angle between the longitudinal axis of the shaft and the extending direction of the slit is 10 degrees or more and 80 degrees or less.

3. 3. The electrode catheter according to claim 1, wherein the slit has a bent portion in a cross section along the longitudinal axis of the shaft.

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