JP6456315B2 - Electrode catheter - Google Patents

Description

  The present invention relates to an electrode catheter capable of tip deflection operation.

  Conventionally, a tip electrode (chip electrode) that constitutes an electrode catheter such as an ablation catheter is formed by integrally forming an electrode portion and a cylindrical small-diameter portion, and is cylindrical in the lumen of the tip flexible portion of the catheter shaft. Is inserted and fixed with an adhesive or the like, thereby being connected to the distal side of the catheter shaft (see, for example, Patent Document 1 and Patent Document 2 below).

JP-A-6-165824 JP-A-9-140803

  However, because the bending rigidity is greatly different between the shaft portion in which the small-diameter portion of the tip electrode is inserted and the shaft portion in which the thin-diameter portion proximal to the proximal end of the thin-diameter portion is not inserted. When the tip electrode receives an external force, for example, when the electrode portion of the tip electrode is pressed against the body tissue, stress concentrates on the shaft portion slightly proximal to the proximal end of the small-diameter portion, An irreversible deformation (bending wrinkle) may occur in the shaft portion, or the tip electrode attached to the catheter shaft may fall off.

  Such a problem is more likely to occur as the electrode portion of the tip electrode is longer.

  For such a problem, it is conceivable to lengthen the small-diameter portion of the tip electrode inserted into the catheter shaft.

However, a plurality of ring-shaped electrodes are usually mounted on the outer peripheral surface of the distal end flexible portion of the catheter shaft.
In addition, since a medical act (procedure) using an electrode catheter is performed while confirming the position and shape of the electrode by an X-ray image, the tip electrode and the ring electrode are both highly radiopaque. It is made of metal.

  For this reason, if the said small diameter part is lengthened so that the proximal end of the small diameter part of a tip electrode may reach the inner side of the ring-shaped electrode located on the most distal side, the thin diameter part of the tip electrode, the ring electrode, Overlap each other on the X-ray image, so that the tip electrode and the ring-shaped electrode cannot be identified, and as a result, the position and shape of the tip electrode cannot be accurately grasped.

The present invention has been made based on the above situation.
An object of the present invention is to prevent irreversible deformation of the distal end flexible portion of the catheter shaft when the distal end electrode receives an external force, or to drop the distal end electrode from the catheter shaft. An object of the present invention is to provide an electrode catheter capable of accurately grasping the position and shape of a tip electrode on an image.

(1) The electrode catheter of the present invention comprises a catheter shaft having a distal end flexible portion, a tubular relay member connected to the distal side of the catheter shaft, and a radiopaque metal. A tip electrode that is a first pole connected to the distal side, and at least one ring-shaped electrode made of a radiopaque metal and attached to the outer peripheral surface of the tip flexible portion of the catheter shaft,
An internal space is formed in the tip electrode,
The relay member is connected to the catheter shaft by inserting a proximal portion thereof into the lumen of the catheter shaft, and connected to the tip electrode by inserting a distal portion thereof into the inner space. Has been
The proximal end of the proximal portion of the relay member is located more proximal than the distal end of the ring-shaped electrode that becomes the second pole,
The relay member has a Rockwell hardness of M50 or more and is made of a material having a higher X-ray transmittance than the X-ray opaque metal constituting the tip electrode and the ring electrode.

  According to the electrode catheter having such a configuration, the catheter shaft and the tip electrode are fixed via a rigid relay member, and the distal end of the proximal portion of the relay member is the second pole of the ring electrode. Since the proximal end of the relay member is located on the proximal side of the distal end (that is, the proximal portion of the relay member extends to the inside of the ring-shaped electrode), the bending rigidity of the shaft portion into which the proximal portion of the relay member is inserted Is held high by the proximal portion, and the bending rigidity of the shaft portion proximal to the proximal end of the proximal portion of the relay member is held high by the ring-shaped electrode serving as the second pole. . As a result, the bending rigidity between the shaft portion in which the proximal portion of the relay member is inserted and the shaft portion in which the proximal portion is not inserted closer to the proximal end of the proximal portion of the relay member is larger. There is no difference, and when the tip electrode receives an external force, stress concentrates on the shaft portion slightly proximal to the proximal end of the proximal portion of the relay member, causing irreversible deformation (bending) in the shaft portion.癖) does not occur and the tip electrode does not fall off the catheter shaft.

  In addition, a relay member is interposed between the catheter shaft and the tip electrode, and this relay member has a higher X-ray transmittance than an X-ray impermeable metal constituting the electrode (contrast properties by X-rays). Since it is made of a low material, the tip electrode and the ring-like electrode (second pole) can be distinguished on the X-ray image, and the position and shape of the tip electrode can be accurately grasped.

(2) In the electrode catheter of the present invention, the radiopaque metal constituting the tip electrode and the ring electrode is platinum, gold, silver, or an alloy containing these as a main component,
The material constituting the relay member is preferably a resin material made of liquid crystal polymer, nylon, polycarbonate or PEEK, or a metal material made of stainless steel or brass (brass).

(3) In the electrode catheter of the present invention, the catheter shaft has a multi-lumen structure on the proximal side of the proximal portion of the relay member, and an inner recess is formed in the proximal portion of the relay member. It is preferable.

  According to the electrode catheter having such a configuration, the distal electrode that extends in the proximal direction from the relay member (the opening formed in the bottom surface of the inner recess) is formed by forming the inner recess in the proximal portion of the relay member. The operation wire for changing the direction of the lead wire and the distal end of the electrode catheter can be reliably sorted into the lumens of the catheter shaft.

(4) In the electrode catheter of the present invention, the tip electrode is integrally formed of a radiopaque metal,
Three or more spherical surfaces or substantially spherical surfaces, each center being on the same straight line;
A curved surface having one reduced diameter portion connected to the spherical surface or substantially spherical surface between adjacent spherical surfaces or substantially spherical surfaces;
The curved surface preferably forms a constriction in the tip electrode between the adjacent spherical surfaces or substantially spherical surfaces.

(5) In the electrode catheter of the present invention, an operation wire which is disposed so as to extend inside the catheter shaft and can be operated by pulling on the proximal side thereof, and a distal end of the operation wire are fixed to the tip electrode. And an anchor member fitted in the inner space of the tip electrode spaced distally from the position where the distal portion of the relay member is inserted,
It is preferable that a through hole for inserting the lead wire of the tip electrode and a through hole for inserting the operation wire are formed in the relay member.

  According to the electrode catheter having such a configuration, by providing the anchor member, the distal end of the operation wire can be arranged and fixed at an appropriate position in the internal space of the tip electrode.

(6) In the electrode catheter of the above (5), it is preferable that an inner recess is formed in a distal portion of the relay member.

  According to the electrode catheter having such a configuration, the inner concave portion is formed in the distal portion of the relay member, so that a part of the solder used when fixing the anchor member can be accommodated in the inner concave portion. it can.

(7) In the electrode catheter of (6) above, it is preferable that the proximal end of the tip electrode is located on the proximal side of the bottom surface of the inner recess formed in the distal portion of the relay member. .

  The metal wall forming (surrounding) the inner space of the tip electrode is usually thin in the vicinity of the proximal end of the tip electrode. According to the electrode catheter having such a configuration, the proximal end of the tip electrode is thinned. Is positioned proximal to the bottom surface of the inner recess formed in the distal portion of the relay member, so that the tip electrode is located outside the thin portion (side wall surrounding the inner recess) in the distal portion of the relay member. It is possible to avoid positioning of the thin-walled portion (metal wall in the vicinity of the proximal end of the tip electrode). As a result, it is possible to prevent a decrease in strength due to the stacking of the thin portions.

(8) In the electrode catheter of (7) above, the distance (axial distance d) between the proximal end of the tip electrode and the bottom surface of the inner recess formed in the distal portion of the relay member is 0. It is preferably 3 to 1 mm.

(9) In the electrode catheter of the present invention, the electrode catheter is disposed so as to extend inside the catheter shaft, and the proximal side thereof includes an operation wire that can be pulled.
The distal portion of the relay member has a function as an anchor member for fixing the distal end of the operation wire to the tip electrode,
Two through holes or through grooves extending in the axial direction are formed in the distal portion of the relay member so as to face each other across the central axis,
The operation wire has a proximal end at one end and the other end, extends in the distal direction from one end side (proximal end side) to the inside of the catheter shaft, and is inserted into the relay member. It extends in the distal direction through one formed through-hole or through-groove, folds at the distal end of the relay member, and proximally through the other through-hole or through-groove formed in the distal portion It is preferable that the wire comprises a single wire extending from the relay member and extending in the proximal direction inside the catheter shaft to the other end (proximal end).

  According to the electrode catheter having such a configuration, the distal portion of the relay member has a function as an anchor member, so that the distal end of the operation wire is disposed at an appropriate position in the inner space of the tip electrode. And can be fixed.

(10) In the electrode catheter of (9), an inner hole or a through hole that extends in the axial direction and opens at least on the proximal side is formed in a distal portion of the relay member. The lead wire of the tip electrode is preferably inserted.

  According to the electrode catheter of the present invention, when the distal electrode receives an external force, the distal flexible portion of the catheter shaft is not irreversibly deformed, and the distal electrode is not dropped from the catheter shaft. The position and shape of the tip electrode can be accurately grasped on the X-ray image.

1 is a side view of an electrode catheter according to a first embodiment of the present invention. It is a longitudinal cross-sectional view which shows the front-end | tip part of the electrode catheter shown in FIG. It is a longitudinal cross-sectional view (III-III sectional drawing of FIG. 2) which shows the front-end | tip part of the electrode catheter shown in FIG. FIG. 4 is a transverse cross-sectional view (IV-IV cross-sectional view of FIG. 2) showing a distal end portion of the electrode catheter shown in FIG. 1. It is a cross-sectional view (VV cross-sectional view of FIG. 2) which shows the front-end | tip part of the electrode catheter shown in FIG. It is a side view which shows the relay member which comprises the electrode catheter shown in FIG. It is a front view which shows the relay member which comprises the electrode catheter shown in FIG. It is a rear view which shows the relay member which comprises the electrode catheter shown in FIG. It is a longitudinal cross-sectional view which shows the relay member which comprises the electrode catheter shown in FIG. It is a longitudinal cross-sectional view which shows the relay member which comprises the electrode catheter shown in FIG. It is a longitudinal cross-sectional view which shows the front-end | tip part of the electrode catheter which concerns on 2nd Embodiment of this invention. It is a side view which shows the relay member which comprises the electrode catheter shown in FIG. It is a front view which shows the relay member which comprises the electrode catheter shown in FIG. It is a rear view which shows the relay member which comprises the electrode catheter shown in FIG. It is a longitudinal cross-sectional view which shows the relay member which comprises the electrode catheter shown in FIG. It is a longitudinal cross-sectional view which shows the relay member which comprises the electrode catheter shown in FIG.

<First Embodiment>
The first embodiment of the present invention will be described below. The electrode catheter 100 of this embodiment shown in FIGS. 1 to 5 is used, for example, for diagnosis or treatment of arrhythmia in the heart.

  The electrode catheter 100 of this embodiment includes a catheter shaft 10 having a distal end flexible portion 15, a tubular relay member 20 connected to the distal side of the catheter shaft 10, and a relay member 20 made of a radiopaque metal. A tip electrode 30 which is a first pole connected to the distal side of the catheter, ring-shaped electrodes 41 to 43 made of radiopaque metal and attached to the outer peripheral surface of the tip flexible portion of the catheter shaft 10, and a catheter An operation wire 50 that is disposed so as to extend along the axial direction inside the shaft 10 and that can be operated by pulling on the proximal side thereof, a thermocouple 55 for measuring the internal temperature of the tip electrode 30, and an operation In order to fix the distal end of the wire 50 to the tip electrode 30, a cylindrical anchor member 70 fitted in the inner space 35 of the tip electrode 30 and a proximal end of the catheter shaft 10 are attached. The relay member 20 is connected to the catheter shaft 10 by inserting the proximal portion 21 into the lumen of the catheter shaft 10 and the distal portion 22 of the relay member 20 is a tip. The proximal end 211 of the proximal portion 21 of the relay member 20 is connected to the tip electrode 30 by being inserted into the internal space 35 of the electrode 30, and the distal end 412 of the ring-shaped electrode 41 serving as the second pole. The relay member 20 has a Rockwell hardness of M50 or more, and has a higher X-ray transmittance than the X-ray opaque metal constituting the tip electrode 30 and the ring electrodes 41 to 43. Constructed from high material.

The electrode catheter 100 of the present embodiment includes a catheter shaft 10, a relay member 20, a tip electrode 30, ring electrodes 41 to 43, an operation wire 50, a thermocouple 55, an anchor member 70, and a connector 80. And.
In FIG. 1, reference numeral 85 denotes a knob for performing a swinging operation (catheter tip deflection operation) of the catheter shaft 10.
In FIG. 2 to FIG. 5, 53 is a conductor of the tip electrode 30, and 54 is a conductor of the ring electrode 41.

The catheter shaft 10 is a multi-lumen tube having a distal end flexible portion 15 and having eight lumens 101 to 108 as shown in FIG.
However, the distal end region of the catheter shaft 10 into which the proximal portion 21 of the relay member 20 is inserted has a single lumen structure.
Here, the “tip flexible portion” refers to the tip portion of the catheter shaft that can be bent (bent) by pulling the operation wire.

  The catheter shaft 10 may be composed of a tube having the same characteristics along the axial direction, but is formed integrally with the distal end flexible portion having relatively high flexibility and the distal end flexible portion in the axial direction. It is preferable that the rear end portion is relatively stiffer than the distal end flexible portion. Examples of the constituent material of the catheter shaft 10 include synthetic resins such as polyolefin, polyamide, polyether block polyamide, and polyurethane.

  The outer diameter of the catheter shaft 10 is usually 2 Fr (0.65 mm) to 8 Fr (2.7 mm).

A distal electrode 30 as a first pole is connected to the distal side of the catheter shaft 10 via a relay member 20 described in detail later.
The tip electrode 30 is integrally formed of a radiopaque metal, and a single contraction connected to these spherical surfaces between three spherical surfaces 30A whose centers are on the same straight line and adjacent spherical surfaces. A curved surface provided with a diameter portion 30B, and the distal electrode 30 is constricted between adjacent spherical surfaces 30A by the curved surface.

The outer diameter of the tip electrode 30 (the maximum diameter in the spherical surface 30 </ b> A) is preferably about the same as the outer diameter of the catheter shaft 10.
A cylindrical internal space 35 is formed in the tip electrode 30. The inner diameter of the tip electrode 30 (the diameter of the internal space 35) is 1.3 to 1.8 mm.

  The X-ray impermeable metal constituting the tip electrode 30 is not particularly limited as long as it is a metal having a good contrast property with respect to X-rays. Preferred examples include platinum, gold, silver, and the like. An alloy having a main component can be used.

Ring-shaped electrodes 41 to 43 made of a radiopaque metal are mounted on the outer peripheral surface of the distal end flexible portion 15 of the catheter shaft 10. Of course, the number of ring-shaped electrodes is not limited to three.
The width of the ring-shaped electrodes 41 to 43 (length in the axial direction of the catheter shaft 10) is, for example, 1.2 to 5.0 mm.

  Examples of the radiopaque metal constituting the ring electrodes 41 to 43 include the same metals as those constituting the tip electrode 30.

  In the relay member 20 that is interposed between the catheter shaft 10 and the tip electrode 30 and constitutes the electrode catheter 100, a proximal portion 21, an intermediate portion 23, and a distal portion 22 are integrally formed.

  In FIG. 6 (FIGS. 6A to 6E) showing the relay member 20, 24 is a through hole for inserting the operation wire 50, 25 is a through hole for inserting the conductive wire 53 of the tip electrode 30 and the thermocouple 55. , 26 is an inner recess formed in the proximal portion 21, 27 is an inner recess formed in the distal portion 22, and 28 is a retaining prevention portion formed on the outer periphery of the proximal portion 21.

  As shown in FIGS. 2 and 3, the proximal portion 21 of the relay member 20 constituting the electrode catheter 100 is inserted into the lumen of the catheter shaft 10 (single lumen in the distal end region of the distal end flexible portion 15) and adhesive. It is fixed by etc. Thereby, the relay member 20 is connected to the catheter shaft 10.

  Here, the proximal end 211 of the proximal portion 21 of the relay member 20 is closer to the proximal side (substantially the middle in the width direction of the ring electrode 41) than the distal end 412 of the ring electrode 41 serving as the second pole. positioned. That is, the proximal portion 21 of the relay member 20 extends to the inside of the ring electrode 41.

  On the other hand, the distal portion 22 of the relay member 20 is inserted into the internal space 35 of the tip electrode 30 and fixed by an adhesive or the like. Thereby, the relay member 20 is connected to the tip electrode 30.

  Thus, the electrode catheter 100 of the present embodiment is characterized in that the relay member 20 is interposed between the catheter shaft 10 and the distal electrode 30.

The constituent material of the relay member 20 is required to have a Rockwell hardness of M50 or more, and preferably M90 or more.
According to the relay member 20 made of a material having a Rockwell hardness of M50 or more, the bending rigidity of the shaft portion into which the proximal portion 21 is inserted can be kept sufficiently high.

  Further, the constituent material of the relay member 20 has a higher X-ray transmittance than that of the X-ray impermeable metal constituting the tip electrode 30 and the ring-shaped electrodes 41 to 43, that is, has a low contrast property by X-rays. is necessary.

  As a result, the proximal end 301 of the tip electrode 30 and the distal end 412 of the ring electrode 41 become clear on the X-ray image, and the tip electrode 30 and the ring electrode 41 can be distinguished. As a result, the position and shape of the tip electrode 30 can be accurately grasped.

  If the relay member is formed of the same X-ray impermeable metal as the tip electrode or the ring electrode, the tip electrode, the relay member, and the ring electrode appear as one electrode on the X-ray image. It is impossible to accurately grasp the position and shape of the tip electrode.

  Examples of the material having both hardness and X-ray transparency as described above include resin materials such as liquid crystal polymer (LCP), nylon, polycarbonate resin, and PEEK resin, and metal materials such as stainless steel and brass (brass). Of these, liquid crystal polymers are preferred.

The operation wire 50 constituting the electrode catheter 100 extends along the axial direction inside the catheter shaft 10 (lumen 101 and lumen 108).
Here, in the operation wire 50, an outward path portion 50 </ b> A extending in the distal direction from one end side extends to the lumen 101, and a return path portion 50 </ b> B that is folded and extends in the proximal direction extends to the lumen 108.

One end and the other end, which are proximal ends of the operation wire 50, are connected to a knob 85 for performing a deflection operation of the catheter shaft 10, thereby enabling a pulling operation.
On the other hand, the distal end of the operation wire 50 is fixed to the tip electrode 30 by a columnar anchor member 70 fitted in the internal space 35 of the tip electrode 30.

  As shown in FIGS. 2 and 3, the anchor member 70 includes two through-holes (through-hole 71 and through-hole 72) extending in the axial direction so as to face each other across the central axis, and the center of the anchor member 70. An inner hole 73 extending on the shaft and opening on the proximal end side is formed.

  The outer diameter of the anchor member 70 is slightly smaller than the diameter of the inner space 35 of the tip electrode 30, and the anchor member 70 is inserted into the inner space 35 of the tip electrode 30 (the distal portion 22 of the relay member 20 is inserted). The inner space of the tip electrode 30 and the outer peripheral surface of the anchor member 70 are filled with solder. In this way, the anchor member 70 is fixed in the internal space 35 of the tip electrode 30 (thereby, the central axes of both of them match), and electrical conductivity and good thermal conductivity are ensured between them. Yes.

  The constituent material of the anchor member 70 is preferably a metal material having good wettability with respect to solder. From this point of view, copper or a copper alloy can be cited as a suitable constituent material for the anchor member 70, and brass (brass) having good thermal conductivity and good wettability with respect to solder is particularly preferable.

  The solder filled in the internal space 35 (the gap with the anchor member 70) of the tip electrode 30 is not particularly limited, and examples thereof include Sn-Pb, Sn-Pb-Ag, and Sn-Pb-Cu. Moreover, Sn-Ag-Cu, Sn-Cu, Sn-Ag, Sn-Ag-Cu-Bi, etc. which are Pb free solders can also be used.

Part of the solder used to fix the anchor member 70 to the inner space 35 of the tip electrode 30 was formed in the inner space 35 on the proximal side of the anchor member 70 and the distal portion 22 of the relay member 20. It can be accommodated in the inner recess 27.
Thus, since the solder can be accommodated also in the distal portion 22 of the relay member 20, the assembly accuracy can be improved.

2 and 3, the spherical surface 30A of the tip electrode 30 has a thick metal wall surrounding the internal space 35, and the reduced diameter portion 30B has a thin metal wall surrounding the internal space 35. ing.
In addition, the metal wall in the vicinity of the proximal end 301 of the tip electrode 30 is also formed to be thin (a thin portion) in the same manner as the metal wall in the reduced diameter portion 30B.

  Further, the side wall surrounding the inner recess 27 formed in the distal portion 22 of the relay member 20 is a thin portion.

  If the thin portion (metal wall near the proximal end 301) of the tip electrode 30 is located outside the thin portion (side wall surrounding the inner recess 27) in the distal portion 22 of the relay member 20, the thin portions are arranged. When are stacked, the strength of the part becomes extremely low.

  Therefore, in the electrode catheter 100 of the present embodiment, the proximal end 301 of the tip electrode 30 is positioned closer to the proximal side than the bottom surface 272 of the inner recess 27 formed in the distal portion 22 of the relay member 20. The thin portion (side wall surrounding the inner recess 27) in the distal portion 22 of the relay member 20 and the thin portion (metal wall in the vicinity of the proximal end 301) of the tip electrode 30 are avoided from being stacked. Yes. As a result, it is possible to prevent a decrease in strength due to the stacking of the thin portions.

Here, the distance (d shown in FIG. 3) between the proximal end 301 of the tip electrode 30 and the bottom surface 272 of the inner recess 27 formed in the distal portion 22 of the relay member 20 is 0.3 to 1 mm. It is preferable.
Further, the thickness of the metal wall constituting the tip electrode 30 at the position where the bottom surface 272 of the inner recess 27 is formed is preferably 25% or more of the thickness (maximum thickness) of the spherical surface 30A.

The operation wire 50 is composed of one wire whose one end and the other end are proximal ends and whose folded portion is a distal end.
The operation wire 50 extends distally from one end side (proximal end side) of the lumen 101 of the catheter shaft 10, extends from the lumen 101 and is inserted into the relay member 20, and passes through the inner recess 26 of the relay member 20. One of the holes 24 extends in the distal direction through the inner recess 27, extends distally from the relay member 20, extends in the distal direction through the inner space 35 of the tip electrode 30, and is inserted into the anchor member 70. 70 extends through the through hole 71 in the distal direction, turns back at the distal end surface 70D of the anchor member 70, extends through the through hole 72 of the anchor member 70 in the proximal direction, and extends proximally from the anchor member 70. The inner space 35 of the tip electrode 30 extends in the proximal direction and is inserted into the relay member 20, and the inner recess 27 of the relay member 20, the other of the through holes 24 and the inner recess 26 extend in the proximal direction. Inserted emanate from joint member 20 into the lumen 108 of the catheter shaft 10, leading to the other end (proximal end) extends proximally in lumen 108.

  As described above, the operation wire 50 extending inside the catheter shaft 10 (lumen 101) passes through the through hole 71 of the anchor member 70 and is folded back at the distal end surface 70D. The distal end of the manipulation wire 50 is firmly fixed to the anchor member 70 (and thus the tip electrode 30) by extending the inside (lumen 108) of the catheter shaft 10 through 72 again. Even if the proximal end of the operation wire 50 is pulled, the distal end of the operation wire 50 does not come out of the inner space 35 of the tip electrode 30.

  Further, since the through hole 71 and the through hole 72 are arranged so as to face each other with the central axis of the anchor member 70 (the central axis of the tip electrode 30) interposed therebetween, the operation wire 50 passed through these through holes is arranged in the vicinity. By pulling the distal end (one end and the other end), the direction of the distal end of the electrode catheter 100 can be changed in both directions, and the flatness of the shape change of the tip flexible portion of the electrode catheter 100 can be improved. Is also excellent.

The constituent material of the operation wire 50 is not particularly limited, and all of the same constituent materials as those of the conventionally known operation wires of the catheter capable of tip deflection operation can be used.
In particular, since the distal end of the operation wire 50 is not directly fixed to the tip electrode by the solder filled in the internal space 35 of the tip electrode 30, a metal material (for example, stainless steel) having low wettability with respect to the solder is used. ) Can be suitably used as a constituent material of the operation wire 50, and even a non-metallic material can be used.

The diameter of the operation wire 50 is, for example, 0.05 to 0.5 mm, preferably 0.1 to 0.3 mm.
The inner diameters of the through hole 71 and the through hole 72 of the anchor member 70 are slightly larger than the diameter of the operation wire 50, and the inner peripheral surface of the through holes 71 and 72 and the outer peripheral surface of the operation wire 50 are formed. A small gap between them is filled with solder.

  The lead wire 53 of the tip electrode 30 passes through the inner space 35 of the tip electrode 30, the inside of the relay member 20 (inner recess 27, through hole 25, inner recess 26), the inside of the catheter shaft 10 (lumen 106), and the inside of the connector 80. It is extended.

The proximal portion of the conducting wire 53 is pulled out from the connector 80 and connected to, for example, a high frequency generator.
The distal portion of the conducting wire 53 is inserted into an inner hole 73 formed in the anchor member 70, and is fixed to the anchor member 70 by solder entering the inner hole 73. Thereby, the conducting wire 53 is electrically connected to the anchor member 70 (and thus the tip electrode 30).
A normal resin-coated conductive wire can be used as the conductive wire 53.
The diameter of the conducting wire 53 is, for example, 0.04 to 0.3 mm, and preferably 0.06 to 0.12 mm.

The thermocouple 55 constituting the electrode catheter 100 is a sensor for measuring the temperature inside the tip electrode 30.
The thermocouple 55 extends through the inner space 35 of the tip electrode 30, the interior of the relay member 20 (inner recess 27, through hole 25, inner recess 26), the catheter shaft 10 (lumen 105), and the connector 80. ing.

  The distal portion (temperature measuring portion) of the thermocouple 55 is fixed to the anchor member 70 by being inserted into the inner hole 73 formed in the anchor member 70 together with the distal portion of the conducting wire 53.

  As shown in FIGS. 2 to 4, the lumen 101 of the catheter shaft 10 through which the forward path portion 50 </ b> A of the operation wire 50 is inserted and one of the through holes 24 of the relay member 20 are not located on the same straight line, The lumen 108 of the catheter shaft 10 through which the return path portion 50B of the operation wire 50 is inserted and the other of the through holes 24 of the relay member 20 are not located on the same straight line.

  Further, the lumen 106 of the catheter shaft 10 through which the conducting wire 53 of the tip electrode 30 is inserted and the through hole 25 of the relay member 20 are not located on the same straight line, and the lumen of the catheter shaft 10 through which the thermocouple 55 is inserted. 105 and the through hole 25 of the relay member 20 are not located on the same straight line.

  Therefore, in the electrode catheter 100 of the present embodiment, an inner recess 26 is formed in the proximal portion 21 of the relay member 20. Thereby, at the time of manufacture of the electrode catheter 100, the operation wire 50 (50A, 50B) extended in the proximal direction from the through holes 24, 24, 25 of the relay member 20, the conducting wire 53 of the tip electrode 30, the thermocouple. 55 becomes movable in the cross-sectional direction, and these can be easily sorted into the lumens 101, 108, 106, 105 of the catheter shaft 10, respectively.

  In the electrode catheter 100 of the present embodiment, by operating the knob 85 of the connector 80, one end or the other end of the operation wire 50 is pulled in the proximal direction, and the distal end flexible portion 15 of the electrode catheter 100 is bent. The distal end of the electrode catheter 100 can be deflected in the direction indicated by the arrow A or B.

  For example, by rotating the knob 85 shown in FIG. 1 in the A1 direction, one end of the operation wire 50 is pulled in the proximal direction, and the distal end of the electrode catheter 100 is deflected in the direction indicated by the arrow A. Further, by rotating the knob 85 in the B1 direction, the other end of the operation wire 50 is pulled in the proximal direction, and the distal end of the electrode catheter 100 is deflected in the direction indicated by the arrow B. If the connector 80 is rotated around the axis, the direction in the A or B direction with respect to the electrode catheter 100 can be freely set while being inserted into the body cavity.

According to the electrode catheter 100 of the present embodiment, the catheter shaft 10 and the tip electrode 30 are fixed via a hard relay member 20 made of a material having a Rockwell hardness of M50 or more. Since the proximal end 211 of the proximal portion 21 is located more proximally than the distal end 412 of the ring electrode 41, the proximal portion 21 of the relay member 20 is formed at the distal end flexible portion 15 of the catheter shaft 10. The bending rigidity of the shaft portion into which the shaft is inserted is held high by the proximal portion 21, and the bending rigidity of the shaft portion proximal to the proximal end 211 of the proximal portion 21 is increased by the ring-shaped electrode 41. Will be held high.
As a result, the bending rigidity of the catheter shaft 10 is increased between the shaft portion in which the proximal portion 21 is inserted and the shaft portion that is located proximal to the proximal end 211 (the proximal portion 21 is not inserted). There is no significant difference, and when the tip electrode 30 receives an external force, stress concentrates on the shaft portion slightly closer to the proximal end 211 than the proximal end 211, causing irreversible deformation (bending wrinkles) in the shaft portion. It is possible to prevent the tip electrode 30 from dropping together with the relay member 20 from the catheter shaft 10.

  Further, according to the electrode catheter 100, the relay member 20 is interposed between the catheter shaft 10 and the tip electrode 30, and the relay member 20 constitutes the tip electrode 30 and the ring-shaped electrodes 41 to 43. Since it is made of a material having a higher X-ray transmittance than the X-ray opaque metal, the tip electrode 30 and the ring electrode 41 can be distinguished on the X-ray image. As a result, the position and shape of the tip electrode 30 Can be grasped accurately.

  Moreover, according to this electrode catheter 100, since the inner recessed part 26 is formed in the proximal part 21 of the relay member 20, it was made to extend in the proximal direction from the through-hole of the relay member 20 at the time of the manufacture. The operation wire 50 (50A, 50B), the conducting wire 53 of the tip electrode 30, and the thermocouple 55 can be easily sorted into the lumens 101, 108, 106, 105 of the catheter shaft 10, respectively.

  Moreover, according to this electrode catheter 100, the anchor member 70 fitted to the internal space 35 of the tip electrode 30 spaced away from the position where the distal portion 22 of the relay member 20 is inserted is provided. Accordingly, the distal end of the operation wire 50 can be arranged and fixed at an appropriate position in the internal space 35 of the tip electrode 30.

  Moreover, according to this electrode catheter 100, since the inner recessed part 27 is formed in the distal part 22 of the relay member 20, a part of solder used when fixing the anchor member 70 is accommodated in the inner recessed part. can do.

  In addition, according to the electrode catheter 100, the proximal end 301 of the tip electrode 30 is located closer to the proximal side than the bottom surface 272 of the inner recess 27 formed in the distal portion 22 of the relay member 20. In addition, it is possible to avoid that the thin portion (metal wall in the vicinity of the proximal end 301) of the tip electrode 30 is located outside the thin portion (side wall surrounding the inner recess 27) of the distal portion 22 of the relay member 20. Further, it is possible to prevent a decrease in strength due to the stacking of the thin wall portions.

Second Embodiment
FIG. 7 is a longitudinal sectional view showing the distal end portion of the electrode catheter according to the second embodiment of the present invention, in which the same reference numerals as those in FIG. 2 denote the electrode catheter 100 of the first embodiment. It is the same configuration.

  The electrode catheter 200 of this embodiment includes a catheter shaft 10 having a distal end flexible portion 15, a tubular relay member 60 connected to the distal side of the catheter shaft 10, and a relay member 60 made of a radiopaque metal. The tip electrode 30 which is the first pole connected to the distal side of the electrode, and three ring-shaped electrodes (see FIG. 5) made of a radiopaque metal and attached to the outer peripheral surface of the tip flexible portion 15 of the catheter shaft 10 7, only the ring-shaped electrodes 41 and 42 are illustrated), and an operation wire 50 that is disposed so as to extend along the axial direction inside the catheter shaft 10, and whose proximal side can be pulled, The relay member 60 includes a lead wire 53 of the tip electrode 30, a thermocouple 55 for measuring the internal temperature of the tip electrode 30, and a connector attached to the proximal end of the catheter shaft 10. The proximal portion 61 is connected to the catheter shaft 10 by being inserted into the lumen of the catheter shaft 10, and the distal portion 62 is inserted into the inner space of the tip electrode 30 to be attached to the tip electrode 30. The proximal end 611 of the proximal portion 61 of the relay member 60 is connected to the proximal side of the distal end 412 of the ring electrode 41 serving as the second pole. The distal end portion 62 of the relay member 60 is made of a material having a hardness of M50 or higher and having a higher X-ray transmittance than the X-ray opaque metal constituting the tip electrode 30 and the ring electrode. It functions as an anchor member for fixing the distal end of the relay member 60 to the tip electrode 30, and extends in the axial direction so as to face the distal portion 62 of the relay member 60 across the central axis thereof. Two through grooves 641 and 642 are formed, and one end and the other end of the operation wire 50 become proximal ends, and the inside (lumen 101) of the catheter shaft 10 extends distally from one end side to the relay member 60. Inserted and extends distally through a through groove 641 formed in the distal portion 62, folded back at the distal end surface 60D of the relay member 60, and proximally through the through groove 642 formed in the distal portion 62 It consists of a single wire extending in the direction, extending from the relay member 60, extending proximally in the catheter shaft 10 (lumen 108) to the other end.

  The electrode catheter 200 of this embodiment includes a catheter shaft 10, a relay member 60, a tip electrode 30, a ring electrode, an operation wire 50, a lead wire 53 of the tip electrode 30, a thermocouple 55, a connector, and the like. It has.

  The catheter shaft 10, the tip electrode 30, the ring electrode 41, the operation wire 50, the lead wire 53 of the tip electrode 30, the thermocouple 55, and the connector constituting the electrode catheter 200 constitute the electrode catheter 100 of the first embodiment. Is the same.

A distal electrode 30 is connected to the distal side of the catheter shaft 10 via a relay member 60.
In the relay member 60 constituting the electrode catheter 200 interposed between the catheter shaft 10 and the tip electrode 30, a proximal portion 61 and a distal portion 62 are integrally formed. In addition, this relay member 60 does not have an intermediate part between the proximal part 61 and the distal part 62, and the relay member 60 does not contact blood directly.

  In the electrode catheter 200 of the present embodiment, the distal portion 62 of the relay member 60 has a function as an anchor member for fixing the distal end of the operation wire 50 to the tip electrode 30.

  In FIG. 8 (FIGS. 8A to 8E) showing the relay member 60, 641 and 642 are formed in the distal portion 62 in order to insert the operation wire 50 (the forward path portion 50A and the return path portion 50B). The through grooves 641 and 642 extend in the axial direction so as to face each other with the central axis of the relay member 60 interposed therebetween.

Reference numeral 65 denotes a through-hole through which the conducting wire 53 and the thermocouple 55 of the tip electrode 30 are inserted, and reference numeral 66 denotes an inner recess formed in the proximal portion 61.
Reference numeral 68 denotes a retaining prevention portion formed on the outer periphery of the proximal portion 61, and reference numeral 63 denotes a screw portion formed on the outer periphery of the distal portion 62. A threaded portion that is screwed into the threaded portion 63 is formed on the inner periphery of the tip electrode 30.

  As shown in FIG. 7, the proximal portion 61 of the relay member 60 is inserted into the lumen of the catheter shaft 10 (single lumen in the distal end region of the distal end flexible portion 15) and fixed by an adhesive or the like. Thereby, the relay member 60 is connected to the catheter shaft 10. Here, the proximal end 611 of the proximal portion 61 of the relay member 60 is located closer to the proximal side than the distal end 412 of the ring-shaped electrode 41. That is, the proximal portion 61 of the relay member 60 extends to the inside of the ring electrode 41.

On the other hand, the distal portion 62 of the relay member 60 is inserted into the internal space of the tip electrode 30 and fixed by an adhesive or the like. Thereby, the relay member 60 is connected to the tip electrode 30.
Thus, in the electrode catheter 200 of the present embodiment, the relay member 60 is interposed between the catheter shaft 10 and the distal electrode 30.

The constituent material of the relay member 60 is required to have a Rockwell hardness of M50 or more, and preferably M90 or more.
According to the relay member 60 made of a material having a Rockwell hardness of M50 or more, the bending rigidity of the shaft portion into which the proximal portion 61 is inserted can be kept sufficiently high.

  Further, the constituent material of the relay member 60 needs to have a higher X-ray transmittance than that of the X-ray impermeable metal constituting the tip electrode 30 and the ring electrode 41, that is, low contrast by X-rays. is there.

  As a result, the proximal end 301 of the tip electrode 30 and the distal end 412 of the ring electrode 41 become clear on the X-ray image, and the tip electrode 30 and the ring electrode 41 can be distinguished. As a result, the position and shape of the tip electrode 30 can be accurately grasped.

  Examples of the material having both hardness and X-ray transparency as described above include resin materials such as liquid crystal polymer (LCP), nylon, polycarbonate resin, and PEEK resin, and metal materials such as stainless steel and brass (brass). be able to.

The operation wire 50 constituting the electrode catheter 200 extends along the axial direction inside the catheter shaft 10 (lumen 101 and lumen 108).
Here, in the operation wire 50, an outward path portion 50 </ b> A extending in the distal direction from one end side extends to the lumen 101, and a return path portion 50 </ b> B that is folded and extends in the proximal direction extends to the lumen 108.

One end and the other end, which are proximal ends of the operation wire 50, are connected to a knob for performing a deflection operation of the catheter shaft 10, thereby enabling a tension operation.
On the other hand, the distal end of the operation wire 50 is fixed to the tip electrode 30 by the distal portion 62 of the relay member 60.

  The operation wire 50 extends distally from one end side (proximal end side) of the lumen 101 of the catheter shaft 10, extends from the lumen 101, and is inserted into the relay member 60. The distal portion 62 extends in the distal direction through the through-groove 641 formed in the distal portion 62 and is folded back at the distal end surface 60D of the relay member 60. The through-groove 642 formed in the distal portion 62 and the inner recess 66 of the relay member 60 are It extends proximally through, extends out of the relay member 60 and is inserted into the lumen 108 of the catheter shaft 10 and extends proximally at the lumen 108 to the other end (proximal end).

  As described above, the operation wire 50 extending inside the catheter shaft 10 (the lumen 101) passes through the through groove 641 formed in the distal portion 62 of the relay member 60 and is distant from the relay member 60. The distal end of the manipulating wire 50 is folded back at the distal end surface 60D and extends again through the through groove 642 formed in the distal portion 62 of the relay member 60 to the inside of the catheter shaft 10 (lumen 108). Can be firmly fixed to the distal portion 62 (and hence the tip electrode 30) of the relay member 60, and even if the proximal end of the operation wire 50 is pulled, the operation wire 50 The distal end of the tip electrode 30 does not escape from the internal space of the tip electrode 30.

  Further, since the through grooves 641 and 642 are arranged so as to face each other with the central axis of the relay member 60 (the central axis of the tip electrode 30) interposed therebetween, the proximal portion of the operation wire 50 passed through these through grooves. By pulling the ends (one end and the other end), the direction of the distal end of the electrode catheter 200 can be changed in both directions, and the flatness of the shape change of the distal end flexible portion of the electrode catheter 200 is also improved. Are better.

  The lead wire 53 of the tip electrode 30 extends through a through hole 65 formed in the distal portion 62 of the relay member 60, an inner recess 66 of the relay member 60, the inside of the catheter shaft 10 (lumen 106), and the inside of the connector. Yes.

The proximal part of the conducting wire 53 is pulled out from the connector and connected to, for example, a high frequency generator.
The distal portion of the conducting wire 53 is inserted into the through hole 65, and is fixed to the distal portion 62 of the relay member 60 by solder penetrating the through hole 65. Thereby, the conducting wire 53 is electrically connected to the relay member 60 (and thus the tip electrode 30).

The thermocouple 55 constituting the electrode catheter 200 extends through a through hole 65 formed in the distal portion 62 of the relay member 60, an inner recess 66 of the relay member 60, the inside of the catheter shaft 10 (lumen 105), and the inside of the connector. Exist.
The distal portion (temperature measuring portion) of the thermocouple 55 is fixed to the distal portion 62 of the relay member 60 by being inserted into the through hole 65 together with the distal portion of the conducting wire 53.

According to the electrode catheter 200 of the present embodiment, the shaft portion into which the proximal portion 61 of the relay member 60 is inserted and the proximal portion from the proximal end 611 (the proximal portion 61 is not inserted). The bending rigidity of the catheter shaft 10 is not significantly different from that of the shaft portion, and when the tip electrode 30 receives an external force, stress is concentrated on the shaft portion slightly proximal to the proximal end 611 and the shaft portion. It is possible to prevent an irreversible deformation (curvature wrinkle) in the portion, or the tip electrode 30 from dropping together with the relay member 60 from the catheter shaft 10.
Further, according to the electrode catheter 200, the tip electrode 30 and the ring-shaped electrode 41 can be identified on the X-ray image, and as a result, the position and shape of the tip electrode 30 can be accurately grasped.
In addition, according to the electrode catheter 200, the distal portion 62 of the relay member 60 has a function as an anchor member, so that the distal end of the operation wire 50 can be properly connected to the internal space of the tip electrode 30. It can be fixed in place.
Further, by reducing the number of parts (anchor members), manufacturing can be facilitated and costs can be reduced.

DESCRIPTION OF SYMBOLS 100 Electrode catheter 10 Catheter shaft 101-108 Lumen 15 Tip flexible part 20 Relay member 21 Proximal part 211 Proximal end of proximal part 22 Distal part 23 Intermediate part 24, 25 Through-hole 26, 27 Inner recessed part 272 Inner recessed part The bottom end 28 of the electrode 30 The tip electrode 301 The proximal end of the tip electrode 30A The spherical surface 30B The reduced diameter portion 35 The internal space 41-43 The ring-shaped electrode 412 The distal end of the ring-shaped electrode 50 The operation wire 50A The forward path portion 50B The return path portion 53 Lead electrode lead wire 54 Ring electrode lead wire 55 Thermocouple 70 Anchor member 70D Anchor member distal end face 71, 72 Through hole 73 Inner hole 80 Connector 85 Knob 200 Electrode catheter 60 Relay member 61 Proximal portion 62 Distal portion 611 Proximal end of proximal portion 641,642 penetration The distal end surface 65 through hole 66 inside recess 68 retaining preventing portion 63 threaded portion of the 60D intermediate member

Claims (10)

A catheter shaft having a flexible tip, a tubular relay member connected to the distal side of the catheter shaft, and a first pole made of a radiopaque metal and connected to the distal side of the relay member A tip electrode and at least one ring electrode made of a radiopaque metal and attached to the outer peripheral surface of the tip flexible portion of the catheter shaft,
An internal space is formed in the tip electrode,
The relay member is connected to the catheter shaft by inserting a proximal portion thereof into the lumen of the catheter shaft, and connected to the tip electrode by inserting a distal portion thereof into the inner space. Has been
The proximal end of the proximal portion of the relay member is located more proximal than the distal end of the ring-shaped electrode that becomes the second pole,
The relay member has a Rockwell hardness of M50 or more, and is made of a material having a higher X-ray transmittance than an X-ray impermeable metal constituting the tip electrode and the ring electrode. . The radiopaque metal constituting the tip electrode and the ring electrode is platinum, gold, silver, or an alloy containing these as a main component,
2. The electrode catheter according to claim 1, wherein the material constituting the relay member is a resin material made of liquid crystal polymer, nylon, polycarbonate or PEEK, or a metal material made of stainless steel or brass (brass). The catheter shaft has a multi-lumen structure proximal to the proximal portion of the relay member;
The electrode catheter according to claim 1 or 2, wherein an inner recess is formed in a proximal portion of the relay member. The tip electrode is integrally formed of a radiopaque metal,
Three or more spherical surfaces or substantially spherical surfaces, each center being on the same straight line;
A curved surface having one reduced diameter portion connected to the spherical surface or substantially spherical surface between adjacent spherical surfaces or substantially spherical surfaces;
The electrode catheter according to any one of claims 1 to 3, wherein the tip electrode is constricted between the adjacent spherical surfaces or substantially spherical surfaces by the curved surface. An operation wire arranged to extend inside the catheter shaft, the proximal side of which is capable of being pulled, and a distal portion of the relay member for fixing the distal end of the operation wire to the tip electrode And an anchor member fitted in the internal space of the tip electrode spaced distally from the position where is inserted,
The through-hole for inserting the conducting wire of the tip electrode and the through-hole for inserting the operation wire are formed in the relay member. The electrode catheter according to 1.   The electrode catheter according to claim 5, wherein an inner recess is formed in a distal portion of the relay member.   The electrode catheter according to claim 6, wherein a proximal end of the tip electrode is located proximal to a bottom surface of the inner recess formed in a distal portion of the relay member.   The distance (d) between the proximal end of the tip electrode and the bottom surface of the inner recess formed in the distal portion of the relay member is 0.3 to 1 mm. Electrode catheter. It is arranged to extend inside the catheter shaft, and the proximal side thereof is provided with an operation wire that can be pulled and operated.
The distal portion of the relay member has a function as an anchor member for fixing the distal end of the operation wire to the tip electrode,
Two through holes or through grooves extending in the axial direction are formed in the distal portion of the relay member so as to face each other across the central axis,
One end and the other end of the operation wire are proximal ends, and the catheter wire extends in the distal direction from one end side and is inserted into the relay member. One penetration formed in the distal portion Extending in a distal direction through a hole or through groove, folded back at a distal end of the relay member, and extending in a proximal direction through the other through hole or through groove formed in the distal portion; The electrode catheter according to any one of claims 1 to 4, wherein the electrode catheter is composed of one wire extending from the inside of the catheter shaft in a proximal direction and reaching the other end.   An inner hole or a through hole extending in the axial direction and opening at least on the proximal side is formed in the distal portion of the relay member, and the lead wire of the tip electrode is inserted into the inner hole or the through hole The electrode catheter according to claim 9.