JP5258005B1 - Electrode catheter - Google Patents

Abstract

The present invention provides an electrode catheter that has excellent tip deflection operability and flatness in the bending direction of a tip flexible portion and can irrigate a surface of a tip electrode with a sufficient amount of liquid.
In a catheter shaft, a distal flexible portion of the shaft, a leaf spring disposed along the central axis of the shaft, an irrigation member connected to the distal end side of the shaft, and a distal end. In the shaft 10, the distal-end-side flow passage forming lumens 11, 11 are formed eccentrically from the central axis in the distal end flexible portion 10 </ b> A, and in the non-flexible portion 10 </ b> A of the shaft 10. A central lumen 16 serving as a liquid flow path is formed along the central axis, and a flow path branching member 70 that communicates the central lumen 16 with each of the front end side flow path forming lumens 11 and 11 is disposed on the shaft 10. Has been.
[Selection] Figure 7

Description

  The present invention relates to an electrode catheter, and more particularly to an electrode catheter having an electrode attached to the tip of the catheter and a mechanism for irrigating a liquid such as physiological saline to the electrode.

  In an ablation catheter that is an electrode catheter, an ablation catheter having an irrigation mechanism for cooling a tip electrode that has become hot during cauterization is used.

  As a conventional catheter equipped with an irrigation mechanism, a catheter that injects physiological saline supplied into the tip electrode through a catheter shaft from a plurality of openings formed on the surface of the tip electrode has been introduced. (For example, refer to Patent Document 1 and Patent Document 2).

  However, conventionally known catheters in which an irrigation opening is formed on the surface of the tip electrode have the following problems (1) to (4).

(1) When an opening is provided on the surface of the tip electrode, an edge is inevitably formed at the opening edge or the like. When cauterization is performed with the tip electrode having such an edge, the current density in the edge portion becomes extremely high, and an abnormal temperature rise occurs in this portion, so that a thrombus may be rapidly formed. .
(2) Even if physiological saline is injected from the opening formed on the surface of the tip electrode, sufficient irrigation cannot be performed on the surface of the tip electrode (the surface cannot be covered with a liquid). In particular, in the catheters described in Patent Document 1 and Patent Document 2 that inject physiological saline in a direction perpendicular to the axis of the tip electrode, the saline cannot be sufficiently brought into contact with the surface of the tip electrode. .
(3) By forming a plurality of openings on the electrode surface, it is impossible to ensure a sufficient surface area of the tip electrode, and efficient cauterization treatment cannot be performed.
(4) The tip electrode constituting the ablation catheter is usually provided with a temperature sensor, and ablation treatment is performed while monitoring and controlling the temperature of the tip electrode and surrounding tissue. However, in the catheters described in Patent Document 1 and Patent Document 2 described above, the tip electrode is cooled more than necessary by the physiological saline supplied to the inside (flow path) of the tip electrode, and the inside of the tip electrode is placed inside the tip electrode. There is a problem that the temperature sensor provided cannot accurately monitor and control the temperature during ablation treatment. In order to solve such a problem, an irrigation member made of a heat insulating material is provided between the tip electrode on which the temperature sensor is arranged and the catheter shaft, and the tip electrode is cooled more than necessary by physiological saline. A technique for preventing this is introduced (see Patent Document 3).

A leaf spring is frequently used as a deflection mechanism for performing a catheter tip deflection operation.
Such a leaf spring is disposed along the central axis of the catheter shaft at the distal flexible portion of the catheter shaft. By adopting a leaf spring as the deflection mechanism, a sufficient torsional rigidity is imparted to the tip flexible portion, and the operability as a catheter capable of tip deflection operation and the flatness in the bending direction of the tip portion of the shaft are improved. The following Patent Document 4 introduces a catheter equipped with an irrigation mechanism that employs a leaf spring (center strut) as a deflection mechanism.

Japanese Patent No. 2562681 JP 2006-239414 A Special table 2009-537243 JP 2010-63886 A

  However, in the electrode catheter equipped with the irrigation mechanism, when a leaf spring is adopted as the deflection mechanism, a lumen that becomes a flow path of a liquid such as physiological saline cannot be formed along the central axis of the catheter shaft. , Must be formed eccentric from the central axis.

  However, when the lumen serving as the liquid flow path is formed eccentrically from the central axis of the catheter shaft, the diameter of the lumen cannot be sufficiently increased. Can not be secured. In addition, the flow path formed eccentrically from the central axis increases the risk of liquid leakage. Furthermore, when the catheter shaft is bent, the flow path that is eccentric from the central axis is more likely to be crushed.

The present invention has been made based on the above situation.
The object of the present invention is good operability as a catheter capable of tip deflection operation, flatness in the bending direction of the tip flexible portion, and can irrigate a sufficient amount of liquid on the surface of the tip electrode, An object of the present invention is to provide an electrode catheter equipped with an irrigation mechanism that has a low risk of liquid leakage and blockage of a flow path.
Another object of the present invention is to provide an electrode catheter capable of uniformly irrigating a liquid from a lumen formed eccentrically at a distal end flexible portion of a catheter shaft in a circumferential direction with respect to the surface of the distal electrode. It is in.

(1) An electrode catheter of the present invention has a distal end flexible portion, a catheter shaft in which a lumen serving as a liquid flow path is formed, and a distal end flexible portion of the catheter shaft at a central axis of the catheter shaft. A leaf spring disposed along, an insulating irrigation member connected to the distal end side of the catheter shaft, and a distal electrode connected to the distal end side of the insulating irrigation member,
In the insulating irrigation member, a plurality of irrigation openings for irrigating the surface of the tip electrode with liquid supplied from the catheter shaft are arranged at equiangular intervals along the outer periphery of the insulating irrigation member. ,
The catheter shaft has at least two lumens (hereinafter, also referred to as “tip-side channel forming lumens”) serving as liquid channels formed eccentrically with respect to the central axis at the distal end flexible portion. In the non-flexible portion of the catheter shaft located on the proximal end side of the distal flexible portion, a single central lumen serving as a liquid flow path is formed along the central axis,
The catheter shaft is provided with a flow path branching member that communicates a central lumen serving as a liquid flow path in the non-flexible portion and each of the distal end side flow path forming lumens in the distal flexible portion. Features.

(2) In the electrode catheter of the present invention, it is preferable that the two distal-end flow passage forming lumens in the distal flexible portion of the catheter shaft are formed so as to face each other with the central axis interposed therebetween.

  According to the electrode catheter having the above-described configuration, each of the central lumen serving as the liquid flow path in the non-flexible portion and (at least) two distal-side flow path forming lumens serving as the liquid flow paths in the distal flexible portion. Is disposed, the liquid flowing through the central lumen can be divided into each of the distal-end-side flow path forming lumens by the flow path branch member and supplied to the irrigation member.

In the electrode catheter of the present invention, the distal-side flow path forming lumen in the distal flexible portion is formed eccentrically from the central axis of the catheter shaft, and a leaf spring is attached to the distal flexible portion along the central axis. It becomes possible to arrange.
In the electrode catheter of the present invention in which a leaf spring is disposed as a deflection mechanism, a sufficient torsional rigidity is imparted to the distal end flexible portion of the catheter shaft, so that a conventional catheter in which the leaf spring cannot be disposed (for example, a catheter shaft) Compared with the electrode catheter described in Patent Document 3 in which a lumen serving as a liquid flow path is formed along the central axis of the shaft over the entire area, the operability as a tip deflection operable catheter, the tip flexible portion It becomes excellent in flatness in the bending direction.

  In addition, since the central lumen serving as the liquid flow path is formed along the central axis in the non-flexible portion of the catheter shaft, the lumen serving as the liquid flow path is formed eccentrically over the entire area of the catheter shaft. Compared with a catheter (for example, the electrode catheter described in Patent Document 2 or Patent Document 4), a larger flow rate (irrigation liquid amount) can be ensured. Therefore, according to the electrode catheter having the above-described configuration, it is possible to irrigate the surface of the tip electrode with a sufficient amount of liquid necessary for cooling or the like.

  Further, by forming the liquid flow path with the central lumen in the non-flexible portion of the catheter shaft, the liquid leakage or bending may occur as compared with the conventional catheter in which the lumen serving as the liquid flow path is formed eccentrically over the entire area of the catheter shaft. In such a case, the risk of blockage of the flow path can be reduced.

(3) In the electrode catheter of the above (2), the distal end flexible portion has the leaf spring disposed therein and a distal end multi-lumen tube in which a plurality of lumens including two lumens serving as liquid flow paths are formed. Composed of
The non-flexible portion includes a rear end side multi-lumen tube on which the central lumen and a plurality of sub-lumens formed around the central lumen are formed inside a coil tube that makes the non-flexible portion inflexible. Composed by being inserted,
The flow path branch member is disposed between the front end side multi-lumen tube and the rear end side multi-lumen tube,
An opening corresponding to the opening of the lumen of the front end multi-lumen tube is formed on the front end surface of the flow path branch member, and the rear end side multi-lumen tube is formed on the rear end surface of the flow path branch member. It is preferable that an opening corresponding to the opening of the lumen is formed.

Here, the “opening corresponding to the opening of the lumen” includes an opening of the same shape as the opening of the lumen arranged opposite to the opening of the lumen, and an inner hole (flow) of the passage branching member. The opening of the inner hole arranged and formed so as to communicate with the passage or the insertion passage) is included.
According to the electrode catheter having such a configuration, each of the plurality of lumens formed in the distal end side multi-lumen tube constituting the distal end flexible portion and the rear end side multi lumen tube constituting the non-flexible portion are formed. In addition, each of the plurality of lumens (the central lumen and the sub-lumen) can be communicated with each other via the flow path branching member.

(4) In the electrode catheter of (3), it is preferable that the flow path branching member is formed with a rear-end-side reduced diameter portion that is inserted into the coil tube.

  According to the electrode catheter having such a configuration, the flow path branching member can act as a stopper for the coil tube.

(5) In the electrode catheter of the present invention described in (3) or (4) above, the flow path branching member, the distal end side multi-lumen tube and the rear end side multi-lumen tube are connected via a joint tube. It is preferable.

  According to the electrode catheter having such a configuration, the connection between the flow branch member and the front-end multi-lumen tube and the connection between the flow branch member and the rear-end multi-lumen tube can be ensured. In addition, leakage of liquid at the contact point between the rear end surface of the front end side multi-lumen tube (the opening surface of the front end side flow passage forming lumen) and the front end surface of the flow passage branch member, the rear end surface and the rear end side of the flow passage branch member It is possible to prevent liquid leakage at the contact point with the tip surface of the multi-lumen tube (opening surface of the central lumen) (according to this, intrusion of liquid into another lumen formed in the shaft).

(6) In the electrode catheter of the present invention, inside the insulating irrigation member, at least two eccentric flow paths communicating with each of the lumens serving as liquid flow paths in the distal flexible portion of the catheter shaft,
A space communicating with the eccentric flow path, and a liquid storage space having no partition wall in the circumferential direction so that the liquid from the eccentric flow path is uniformly distributed in the circumferential direction of the insulating irrigation member; ,
It is preferable that a plurality of branch channels are formed that communicate with the storage space and extend in the distal direction while inclining outward to reach each of the plurality of irrigation openings.

  According to the electrode catheter having such a configuration, since the irrigation opening is formed in the insulating irrigation member, it is not necessary to form an opening in the tip electrode, and there is no edge associated with the formation of the opening. In this case, an abnormal temperature rise does not occur in a part of the tip electrode, thereby suppressing the formation of a thrombus. Moreover, since it is not necessary to form an opening in the tip electrode, a sufficient surface area can be ensured, and efficient ablation treatment can be performed.

  In addition, since liquid is irrigated from the insulating irrigation member to the surface of the tip electrode, a sufficient amount of liquid can be brought into contact with the surface of the tip electrode. Since it flows along the surface of the tip electrode from the base end portion of the tip electrode to the tip portion, it has excellent cooling effect on the surface of the tip electrode, and the blood near the tip electrode surface is sufficiently stirred and diluted. Even in this case, an excellent thrombus formation inhibitory effect is exhibited.

  Moreover, since the several irrigation opening arrange | positioned at equal angle intervals along the outer periphery of an insulating irrigation member is formed, it can irrigate over the whole area of the circumferential direction with respect to the surface of a tip electrode.

  Furthermore, since the eccentric flow path is formed inside the insulating irrigation member, the liquid from the lumen of the catheter shaft (liquid flow path formed eccentrically) can be circulated toward the storage space.

  Furthermore, the insulating irrigation member has a liquid storage space that does not have a partition wall in the circumferential direction thereof, communicates with the storage space, and extends in the distal direction while inclining outward to reach each of the plurality of irrigation openings. By forming a plurality of branch flow paths, the liquid that has reached the storage space through the eccentric flow path is arranged so that the liquid is uniformly distributed in the circumferential direction in the storage space, and then the tip direction Since the irrigation openings are sprayed (irrigated) through each of the plurality of branch channels extending in the same direction, there is no variation in the amount of liquid ejected between the irrigation openings arranged at equiangular intervals, and insulation is achieved. It becomes possible to perform uniform injection (irrigation) in the circumferential direction of the sexual irrigation member, and the surface of the tip electrode can be uniformly irrigated over the entire circumferential direction.

  Furthermore, the branch flow path formed inside the insulating irrigation member is formed so as to be inclined outward (outside in the radial direction of the insulating irrigation member). Can be placed on the outside, so that it is possible to irrigate the surface of a tip electrode having a certain size (for example, a tip electrode having a diameter equal to or larger than the tube diameter of the catheter shaft).

According to the electrode catheter of the present invention, the operability as a catheter capable of tip deflection operation, the flatness of the bending direction of the tip flexible portion are good, and a sufficient amount of liquid is irrigated on the surface of the tip electrode. The risk of liquid leakage and blockage of the flow path is low.
According to the electrode catheter of the present invention, it is possible to uniformly irrigate the liquid from the lumen formed eccentrically at the distal flexible portion of the catheter shaft in the circumferential direction with respect to the surface of the distal electrode.

It is a front view of the ablation catheter which concerns on one Embodiment of the electrode catheter of this invention. It is a longitudinal cross-sectional view in the principal part (essential part including the boundary of a front-end | tip flexible part and a non-flexible part) of the ablation catheter shown in FIG. It is a cross-sectional view (III-III cross-sectional view of FIG. 2 (FIG. 7)) in the main part of the ablation catheter shown in FIG. FIG. 4 is a transverse sectional view (FIG. 2 (FIG. 7) IV-IV sectional view) of the main part of the ablation catheter shown in FIG. It is a cross-sectional view (VV cross-sectional view of FIG. 2 (FIG. 7)) in the main part of the ablation catheter shown in FIG. It is a cross-sectional view (VI-VI cross-sectional view of FIG. 2 (FIG. 7)) in the main part of the ablation catheter shown in FIG. It is a longitudinal cross-sectional view (VII-VII sectional drawing of FIG. 6) in the principal part of the ablation catheter shown in FIG. It is a perspective view which shows the flow-path branch member which comprises the ablation catheter shown in FIG. It is a perspective view which shows the flow-path branch member which comprises the ablation catheter shown in FIG. It is a perspective view in the principal part of the ablation catheter shown in FIG. It is a perspective view in the principal part of the ablation catheter shown in FIG. It is a perspective view in the principal part of the ablation catheter shown in FIG. It is a perspective view in the principal part of the ablation catheter shown in FIG. It is a longitudinal cross-sectional view in the front-end | tip part of the ablation catheter shown in FIG. It is a cross-sectional view (CC cross-sectional view of FIG. 14 (FIG. 19)) at the distal end portion of the ablation catheter shown in FIG. It is a cross-sectional view (FIG. 14 (FIG. 19) BB cross-sectional view) at the distal end portion of the ablation catheter shown in FIG. It is a cross-sectional view (DD sectional view of FIG. 14 (FIG. 19)) at the distal end portion of the ablation catheter shown in FIG. It is a cross-sectional view (AA sectional view of FIG. 14 (FIG. 19)) at the distal end portion of the ablation catheter shown in FIG. It is a longitudinal cross-sectional view (FF sectional drawing of FIG. 15) in the front-end | tip part of the ablation catheter shown in FIG. It is a perspective view which shows the irrigation member which comprises the ablation catheter shown in FIG. It is a perspective view which shows the irrigation member which comprises the ablation catheter shown in FIG. It is a longitudinal cross-sectional view (GG sectional drawing of FIG. 16) in the front-end | tip part of the ablation catheter shown in FIG. It is a cross-sectional view (HH cross-sectional view of FIG. 22) at the distal end portion of the ablation catheter shown in FIG. FIG. 23 is a transverse cross-sectional view (II cross-sectional view of FIG. 22) at the distal end portion of the ablation catheter shown in FIG. 1. FIG. 23 is a transverse cross-sectional view (a cross-sectional view taken along the line JJ in FIG. 22) at the distal end portion of the ablation catheter shown in FIG. 1.

Hereinafter, an embodiment of an electrode catheter of the present invention will be described with reference to the drawings.
The electrode catheter shown in FIGS. 1 to 25 is an ablation catheter of the present invention used for treatment of arrhythmia in the heart.

In this embodiment, the ablation catheter 100 has a distal end flexible portion 10A, a catheter shaft 10 having a lumen serving as a liquid flow path, and an insulating irrigation member 20 connected to the distal end side of the catheter shaft 10. A distal electrode 30 connected to the distal end side of the irrigation member 20, a ring electrode 40 mounted on the outer peripheral surface of the distal flexible portion 10A of the catheter shaft 10, and a distal flexible portion 10A of the catheter shaft 10. The tension wires 61 and 62 constituting the deflection mechanism for bending, the leaf spring 65 disposed along the central axis of the catheter shaft 10 and constituting the deflection mechanism together with the tension wires 61 and 62, and the catheter shaft 10 A control handle 700 connected proximally and a liquid injection tube 800;
The irrigation member 20 has eight irrigation openings 25A for ejecting (irrigating) the liquid supplied from the catheter shaft 10 onto the surface of the tip electrode 30 along the outer periphery of the irrigation member 20 at an equiangular interval (45 °). Spaced);
In the distal flexible portion 10A (the distal multi-lumen tube 101), the catheter shaft 10 has two distal flow path forming lumens 11 and 11 that serve as liquid flow paths facing each other across the central axis (see FIG. That is, each is formed eccentrically from the central axis), and the two lumens 12 and 12 that serve as insertion passages for the pulling wires 61 and 62 and the two passages that serve as lead passages for the ring electrode 40 Lumens 13 and 13 are formed, and in the non-flexible portion (rear end side multi-lumen tube 102) of the catheter shaft 10 located on the proximal end side of the distal end flexible portion 10A, the central lumen 16 serving as a liquid flow path is the center. 8 sub-lumens 171 to 178 are formed along the axis;
The catheter shaft 10 has a flow passage branch that communicates the central lumen 16 that is a liquid flow path in the non-flexible portion and the distal-end flow passage forming lumens 11 and 11 that are liquid flow paths in the distal flexible portion 10A. A member 70 is disposed;
In the irrigation member 20, there are two eccentric channels 23, 23 communicating with the distal-side channel forming lumens 11, 11 serving as a liquid channel in the distal flexible portion 10 A of the catheter shaft 10, and the eccentric channel 23. , 23, and a liquid storage space 24 having no partition walls in the circumferential direction so that the liquid from the eccentric flow paths 23, 23 is uniformly distributed in the circumferential direction of the irrigation member 20, Eight branch channels 25 are formed which communicate with the storage space 24 and extend in the distal direction while inclining outward to reach each of the eight irrigation openings 25A. A liquid guide groove 26 extending in the distal direction from each of the irrigation openings 25A is formed continuously to each of the branch flow paths 25;
A liquid guide groove 36 is formed on the surface of the proximal end portion of the tip electrode 30 so as to be continuous with each of the guide grooves 26 of the irrigation member 20;
The irrigation member 20 has a front-side recess 21A that can be fitted to the cylindrical portion 33 of the front-end electrode 30, and a recess 21B that is also formed on the rear-end side. And a first small diameter portion 221 that can be fitted in the rear end concave portion 21B of the first component 21, and two eccentric flow paths 23, 23 are formed inside. Constituted by fitting the second part 22 being made;
The depth (d ₂₁ ) of the rear end side recess 21B of the first component 21 is formed deeper than the length (d ₂₂ ) of the distal end side small diameter portion 221 of the second component 22, thereby The storage space 24 (the bottom surface (rear end surface) 21b and the inner peripheral surface of the rear end recess 21B of the first component 21) and the front end surface of the front end side small diameter portion 221 of the second component 22 at the fitting part with the second component 22 22a) is formed.

  As shown in FIG. 1, the ablation catheter 100 includes a catheter shaft 10 having a flexible tip portion 10A, an irrigation member 20, a tip electrode 30, a ring electrode 40, a control handle 700, and a liquid injection tube 800. And comprising.

The infusion tube 800 shown in FIG. 1 is connected to the catheter shaft 10 through the inside of the control handle 700, and through the infusion tube 800, the lumen of the catheter shaft 10 (the central lumen 16 and the distal side flow path formation). The liquid is supplied to the lumens 11, 11).
Here, as the “liquid”, physiological saline can be exemplified.

  A control handle 700 shown in FIG. 1 is connected to the proximal end side of the catheter shaft 10 and includes a rotating plate 705 for performing a distal end deflection operation of the catheter.

The catheter shaft 10 constituting the ablation catheter 100 has a flexible distal end portion 10A.
Here, the “tip flexible portion” refers to the tip portion of the catheter shaft that can be bent (bent) by pulling the wire for pulling the tip (the pulling wires 61 and 62).

  As shown in FIGS. 2, 6, and 7, the distal end flexible portion 10 </ b> A of the catheter shaft 10 includes a leaf spring 65 and a plurality of lumens including distal end side flow path forming lumens 11 and 11. The distal end side multi-lumen tube 101 and the outer skin member 103 covering the same are constituted.

  As shown in FIGS. 6 and 7, the distal end side passage forming lumens 11, 11 serving as liquid passages are opposed to the distal end flexible portion 10 </ b> A of the catheter shaft 10 across the central axis of the catheter shaft 10. Is formed.

  Further, as shown in FIG. 6, the distal end flexible portion 10 </ b> A serves as an insertion passage for the two lumens 12, 12 serving as insertion passages for the pulling wires 61, 62 and the lead wire 40 </ b> L of the ring-shaped electrode 40. Lumens 13 and 13, a lumen 14 serving as an insertion path for the lead wire 30 </ b> L of the tip electrode 30, and a lumen 15 serving as an insertion path for the lead wire 35 </ b> L of the temperature sensor (thermocouple) are formed. As shown in FIG. 6, in the present embodiment, three lead wires 40 </ b> L are inserted through one of the lumens 13 and 13.

The catheter shaft 10 constituting the ablation catheter 100 has a non-flexible portion on the proximal end side of the distal flexible portion 10A.
Here, the “non-flexible portion” refers to a portion that cannot be bent (bent) even by pulling a wire for tip deflection operation.

  As shown in FIGS. 2, 4, and 7, the non-flexible portion of the catheter shaft 10 has a rear end multi-lumen in which a central lumen 16 and eight sub-lumens 171 to 178 formed around the central lumen 16 are formed. The tube 102, a coil tube 80 into which the rear end side multi-lumen tube 102 is inserted, and an outer skin member 103 that covers the coil tube 80 are configured.

  The coil tube 80 mounted inside the catheter shaft 10 is formed by winding a wire with a rectangular cross section or a circular shape into a coil shape, and a reaction force of a tensile force acting on the tension wire 61 or the tension wire 62 is generated. To receive. Thereby, when a tensile force is applied to the pulling wire 61 or the pulling wire 62, it is possible to prevent the portion (non-flexible portion) of the catheter shaft 10 to which the coil tube 80 is attached from bending. .

  As shown in FIGS. 4 and 7, a non-flexible portion of the catheter shaft 10 is formed with a central lumen 16 serving as a liquid channel along the central axis.

  Further, as shown in FIG. 4, the non-flexible portion includes sub-lumens 171 and 175 serving as insertion paths for the pulling wires 61 and 62, sub-lumens 176 serving as insertion paths for the lead wire 40L of the ring electrode 40, and Eight sub-lumens 171 to 178 including a sub-lumen 172 serving as an insertion path for the lead wire 30L of the tip electrode 30 and a sub-lumen 173 serving as an insertion path for the lead wire 35L of the temperature sensor (thermocouple) are formed. .

As shown in FIGS. 2 and 4 to 6, the catheter shaft 10 (lumens 12 and 12 in the distal end flexible portion 10 </ b> A, insertion passages 71 and 72 in a flow path branching member 70 described later, sublumen 171 in an inflexible portion, and FIG. , 175) are provided with tension wires 61, 62 for bending the tip flexible portion 10A (tip deflection operation). The rear ends of the tension wires 61 and 62 are connected to a rotating plate 705 (see FIG. 1) of the control handle 700, respectively. On the other hand, the front ends of the tension wires 61 and 62 are fixed on the outer peripheral surface (the storage groove 226) of the irrigation member 20 (second component 22).
For example, when the rotating plate 705 is rotated in the A1 direction shown in FIG. 1, the pulling wire 61 is pulled, and the distal end flexible portion 10A of the catheter shaft 10 is deflected in the arrow A direction and rotated in the B1 direction shown in FIG. When the plate 705 is rotated, the pulling wire 62 is pulled, and the distal end flexible portion 10A of the catheter shaft 10 is deflected in the arrow B direction.

As shown in FIG. 6, the distal end flexible portion 10A of the catheter shaft 10 has the catheter shaft 10 on a plane perpendicular to the arrangement direction of the pulling wires 61 and 62 (the bending direction of the distal end flexible portion 10A). A leaf spring 65 is disposed along the central axis.
By disposing the leaf spring 65 on the distal end flexible portion 10A, anisotropy (flatness) in the bending direction of the distal end flexible portion 10A is ensured and sufficient torsional rigidity is imparted to the distal end flexible portion 10A. Therefore, the operability during the tip deflection operation can be improved.

The outer diameter of the catheter shaft 10 is preferably 1.0 to 3.0 mm, more preferably 1.6 to 2.7 mm, and 2.36 mm as a suitable example.
The length of the catheter shaft 10 is preferably 600 to 1500 mm, and more preferably 900 to 1200 mm.

The catheter shaft 10 includes a central lumen 16 serving as a liquid flow path in the non-flexible portion (rear end side multi-lumen tube 102) and a distal end serving as a liquid flow path in the distal end flexible portion 10A (front end side multi-lumen tube 101). A channel branching member 70 that communicates with each of the side channel forming lumens 11 and 11 is disposed.
The channel branching member 70 is preferably made of, for example, a molded body of an insulating resin or an insulating ceramic, and is preferably formed of a molded body obtained by a ceramic injection molding method (CIM).

As shown in FIGS. 2, 7, and 10, the flow path branching member 70 is disposed between the front end side multi-lumen tube 101 and the rear end side multi-lumen tube 102.
A front end surface 70 </ b> A of the flow path branching member 70 is in contact with a rear end surface of the front end side multi-lumen tube 101. The flow path branching member 70 has a rear end side reduced diameter portion 76 inserted into the coil tube 80, and a rear end surface 70 </ b> B of the flow path branching member 70 is in contact with the front end surface of the rear end side multi-lumen tube 102. ing. By inserting the rear end side reduced diameter portion 76 of the flow path branching member 70 into the coil tube 80, the flow path branching member 70 functions as a stopper of the coil tube 80 (the coil tube 80 is caused by the flow path branching member 70). Is prevented from moving to the tip side.)

  As shown in FIGS. 2, 3, 5, and 7 to 9, the passage branch member 70 has an insertion passage 71 for the tension wire 61, an insertion passage 72 for the tension wire 62, and a liquid branch. A forming flow path 73, an insertion path 74 for the lead wire 30L of the tip electrode 30 and the temperature sensor lead line 35L, and an insertion path 75 for the lead wire 40L of the ring electrode 40 are formed. Here, the “branch forming channel” refers to a channel that branches one channel into a plurality (two) of branch channels (that is, a channel including a branched portion).

  Further, the rear end surface 70B of the flow path branching member 70 shown in FIGS. 3 and 8 is formed with an opening 73B of the branch forming flow path 73 (opening before branching), and an opening 71B of the insertion passage 71, An opening 72B of the insertion path 72, an opening 74B of the insertion path 74, and an opening 75B of the insertion path 75 are formed. These openings formed in the rear end face 70B of the flow path branching member 70 correspond to the lumen openings formed in the front end face of the rear end side multi-lumen tube 102 shown in FIG.

  That is, the opening 73B of the branch forming flow path 73 formed in the rear end face 70B corresponds to the opening of the central lumen 16 (liquid flow path) formed in the front end face of the rear end side multi-lumen tube 102, and the insertion passage 71 , 72 correspond to the openings of the sub-lumens 171, 175 (insertion passages of the pulling wires 61, 62), and the openings 74B of the insertion passage 74 correspond to the sub-lumens 172-174 (the lead wire 30L of the tip electrode 30). And the opening 75B of the insertion passage 75 corresponds to the opening of the sub-lumen 176 (insertion passage of the lead wire 40L of the ring electrode 40). .

  On the other hand, openings (opening after branching) 731A and 732A of the branch forming flow path 73 are formed on the distal end surface 70A of the flow path branching member 70 shown in FIGS. 71A, the opening 72A of the insertion path 72, the opening 74A of the insertion path 74, and the opening 75A of the insertion path 75 are formed. These openings formed in the distal end surface 70A of the flow path branching member 70 correspond to the lumen openings formed in the rear end surface of the distal end side multi-lumen tube 101 shown in FIG.

  That is, the openings 731A and 732A of the branch forming flow path 73 formed on the front end surface 70A correspond to the openings of the front end side flow path forming lumens 11 and 11 formed on the rear end face of the front end side multi-lumen tube 101, and are inserted. The openings 71A and 72A of the passages 71 and 72 correspond to the openings of the lumens 12 and 12 (insertion passages of the pulling wires 61 and 62), and the opening 74A of the insertion passage 74 is the lumen 14 (of the lead wire 30L of the tip electrode 30). The opening 75A of the insertion passage 75 corresponds to the opening of the lumen 13 (insertion passage of the lead wire 40L of the ring-shaped electrode 40) corresponding to the opening of the lumen 15 and the lumen 15 (insertion passage of the temperature sensor lead wire 35L). doing.

  According to such a configuration, the lumens (tip-side channel forming lumens 11, 11, lumen 12, 12, etc.) formed in the tip-side multi-lumen tube 101 constituting the tip flexible portion 10A via the channel branching member 70. 12, lumen 13, lumen 14, lumen 15) and a plurality of lumens (central lumen 16 and sub-lumens 171 to 178) formed in the rear end side multi-lumen tube constituting the non-flexible portion. Can communicate.

As shown in FIGS. 3, 4, 7, 10, and 11, the branch forming flow path 73 (rear end portion where the opening 73 </ b> B is located) of the flow path branching member 70 and the rear end side multi-lumen tube 102 are The central lumen 16 communicates with the joint tube 52.
Thereby, the connection between the flow path branching member 70 and the rear end side multi-lumen tube 102 can be ensured, and the rear end face 70B (formation surface of the opening 73B) of the flow path branching member 70 and the rear end Liquid leakage at the contact point with the tip surface of the side multi-lumen tube 102 (opening surface of the central lumen 16) can be prevented.

Further, as shown in FIGS. 5, 6, 7, 12, and 13, the branch forming flow path 73 (the front end portion where the openings 731A and 732A are located) of the flow path branching member 70 and the front end side multi-lumen tube are provided. The distal end side flow path forming lumens 11 and 11 of the 101 communicate with each other through joint tubes 51 and 51.
Thereby, the connection between the flow path branching member 70 and the front end side multi-lumen tube 101 can be ensured, and the front end face 70A (formation surface of the opening 731A and the opening 732A) of the flow path branching member 70, Liquid leakage at the contact point with the rear end surface of the distal end side multi-lumen tube 101 (the opening surface of the distal end side flow path forming lumens 11, 11) can be prevented.

As described above, the front end side flow passage forming lumens 11 and 11 formed in the front end side multi-lumen tube 101 and the central lumen 16 formed in the rear end side multi lumen tube 102 via the flow passage branching member 70. , The liquid flow path in the distal flexible portion 10A can be formed eccentrically from the central axis of the catheter shaft 10, and the liquid flow path in the non-flexible portion is formed along the central axis of the catheter shaft 10. can do.
As described above, the central branch 16 (liquid channel in the non-flexible portion) formed in the rear end side multi-lumen tube 102 and the front end side formed in the front end side multi-lumen tube 101 by the flow path branching member 70. By connecting the flow path forming lumens 11 and 11 (liquid flow paths in the distal end flexible portion 10A), the liquid flowing through the central lumen 16 is caused to flow into the front end side flow path forming lumens 11 and 11 by the flow path branching member 70, respectively. The irrigation member 20 can be divided and supplied. Further, the liquid flow path in the distal flexible portion 10A can be formed eccentrically from the central axis of the catheter shaft 10, and the liquid flow path in the non-flexible portion can be formed along the central axis of the catheter shaft 10. .
As a result, the leaf spring 65 can be disposed along the central axis in the distal flexible portion 10A, and sufficient flexible rigidity is imparted to the distal flexible portion 10A of the catheter shaft 10 so that the leaf spring is disposed. Compared to conventional catheters that cannot be used, excellent operability and flatness in the bending direction can be exhibited, and a sufficient flow rate (irrigation fluid volume) can be obtained by the central lumen 16 serving as a liquid flow path in the non-flexible portion. ) Can be secured.

In the ablation catheter 100, the ejection (irrigation) of the liquid onto the surface of the distal electrode 30 is performed by the irrigation member 20 located on the rear end side of the distal electrode 30.
20 and 21 are perspective views showing the shape of the irrigation member 20 constituting the ablation catheter 100. FIG.

  As shown in FIGS. 14 and 19 to 22, the irrigation member 20 is configured by fitting a first part 21 and a second part 22 together.

The second component 22 constituting the irrigation member 20 is formed of a molded body in which a straight body portion 223 and a distal end side small diameter portion 221 having an outer diameter smaller than that of the straight body portion 223 are integrally formed.
20 and 21, the front end side small-diameter portion 221 of the second component 22 does not appear on the drawings because it is fitted inside the first component 21 (rear end side recess 21 </ b> B).

The outer diameter of the straight body portion 223 of the second component 22 is preferably 0.80 to 2.80 mm, more preferably 1.80 to 2.12 mm, and 1.96 mm if a suitable example is shown. .
The outer diameter of the small-diameter portion 221 on the distal end side of the second component 22 is preferably 0.60 to 2.60 mm, more preferably 0.40 to 1.70 mm, and 1.45 mm if a suitable example is shown. .

  As shown in FIGS. 16, 17, 19, and 21, the second component 22 has a central through hole 224 formed along the central axis thereof, and the central axis is located on both sides of the central through hole 224. Eccentric flow paths 23, 23 extending in parallel with each other are formed. The central through-hole 224 and the eccentric flow paths 23 and 23 are through-holes extending from the front end surface 22a of the second component 22 (front end side small diameter portion 221) to the rear end surface 22b of the second component 22 (straight barrel portion 223).

As shown in FIG. 19, each of the openings of the eccentric flow paths 23, 23 in the rear end surface 22 b of the second component 22 (BB cross section in FIG. 14 shown in FIG. 16) is the distal end surface (FIG. 15) of the catheter shaft 10. 14 facing each of the openings of the front end side flow path forming lumens 11, 11.
The distal end side flow path forming lumens 11 and 11 of the catheter shaft 10 and the eccentric flow paths 23 and 23 of the irrigation member 20 (second component 22) communicate with each other via joint tubes 51 and 51. As a result, the connection between the catheter shaft 10 and the irrigation member 20 can be ensured, and the distal end surface of the catheter shaft 10 (opening surfaces of the distal-side flow path forming lumens 11, 11) and the irrigation member 20 It is possible to prevent leakage of liquid at a contact point with the rear end surface 22b (opening surfaces of the eccentric flow paths 23, 23) of the rear end surface, and further, infiltration of liquid into the shaft accompanying this.

As shown in FIG. 19, the cross-sectional shape of the eccentric flow passages 23, 23 penetrating through the second part 22 (the straight body 223 and the distal side small diameter part 221) is from the inside of the straight body 223 to the distal side small diameter part 221. Immediately before reaching the inside (step portion indicated by 231 in FIG. 19), the shape changes from a circular shape to a substantially semicircular shape. Therefore, although the opening shape of the eccentric flow paths 23 and 23 in the rear end surface 22b (BB cross section of FIG. 14 shown in FIG. 16) is circular, the front end surface 22a (FIG. 17) of the second component 22 is circular. The opening shape of the eccentric flow paths 23 and 23 in the DD cross section in FIG. 14 is substantially semicircular.
In this way, by changing the cross-sectional shape of the eccentric flow paths 23, 23, the thickness (for example, a thickness of 60 μm or more) of the molding material that defines the eccentric flow paths 23, 23 at the distal end side small diameter portion 221 is ensured. be able to.

  In addition, as shown in FIGS. 14, 20 and 21, storage grooves 226 and 226 for storing and fixing the distal ends of the tension wires 61 and 62 on the outer peripheral surface of the second component 22 (straight barrel portion 223). Is formed.

Further, as shown in FIGS. 20 to 22 and FIG. 25, a ring-shaped electrode 40 (first and second ring electrodes from the tip) is formed on the outer peripheral surface of the second component 22 (straight barrel portion 223). A storage groove 225 is formed to store the lead wire 40L.
As shown in FIG. 22, the storage groove 225 includes a shallow groove portion 225a, an inclined portion 225b, and a deep groove portion 225c from the front end toward the rear end.
Here, the width of the storage groove 225 is preferably 0.15 to 0.35 mm, and 0.26 mm if a suitable example is shown.
The depth of the shallow groove portion 225a of the storage groove 225 is preferably 0.10 to 0.20 mm, and 0.12 mm if a suitable example is shown.
Moreover, it is preferable that the depth of the deep groove part 225c of the storage groove 225 is 0.15-0.65 mm, and it will be 0.50 mm if a suitable example is shown.

  The first part 21 constituting the irrigation member 20 includes a straight body part 213, a large diameter part 212 having a larger outer diameter than the straight body part 213, and a reduced diameter part 211 that is reduced in diameter toward the distal end. It consists of a molded body formed in

  The outer diameter of the straight body portion 213 of the first component 21 is substantially the same as the outer diameter of the straight body portion 223 of the second component 22, and the outer diameter of the large diameter portion 212 is the same as the outer diameter of the catheter shaft 10. Substantially the same. The minimum outer diameter of the reduced diameter portion 211 of the first component 21 is substantially the same as the outer diameter of the neck portion 32 of the tip electrode 30.

As shown in FIGS. 14, 19, and 22, a front end side recess 21 </ b> A that can be fitted to the rear end portion (cylindrical portion 33) of the front end electrode 30 is formed on the front end side of the first component 21. . Further, a rear end side recess 21 </ b> B that can be fitted to the front end side small diameter portion 221 of the second component 22 is formed on the rear end side of the first component 21.
Here, the depth (represented by d ₂₁ in FIG. 19) of the rear end side recess 21B of the first component 21 is greater than the length (represented by d ₂₂ in FIG. 19) of the distal end side small diameter portion 221 of the second component 22. Deeply formed.

  As shown in FIGS. 19 and 20, eight irrigation openings for injecting (irrigating) the liquid supplied from the catheter shaft 10 onto the surface of the tip electrode 30 are provided in the first component 21 (the reduced diameter portion 211). 25A is arranged along the outer periphery of the irrigation member 20 at equiangular intervals (45 ° intervals).

Further, in the first component 21, eight branch flow paths 25 (in the irrigation openings 25A) extending in the distal direction while being inclined outward from the bottom surface (rear end surface) 21b of the rear end side recess 21B ( A through hole) is formed.
As shown in FIG. 18, the openings of the branch flow passages 25 on the bottom surface (rear end surface) 21 b of the rear end side recess 21 </ b> B are also arranged at equal angular intervals (45 ° intervals) along the circumferential direction of the irrigation member 20. ing.

Each of the eight branch flow paths 25 is formed so as to be inclined outward (outside in the radial direction of the irrigation member 20) with respect to the axial direction of the irrigation member 20.
Thereby, it is possible to sufficiently irrigate the surface of the tip electrode having a certain size.
Here, the inclination angle of the branch channel 25 is preferably 3 to 45 °, more preferably 5 to 13 °, and 7 ° if a suitable example is shown.

  In addition, a liquid guide groove 26 is formed in the distal end portion (the reduced diameter portion 211) of the first component 21 so as to be continuous with each of the eight branch flow paths 25 and extend in the distal direction from each of the irrigation openings 25A. ing.

  The irrigation member 20 (first component 21) is provided with eight branch channels 25, irrigation openings 25A, and eight liquid guide grooves 26 along the outer periphery of the irrigation member 20 at intervals of 45 °. However, in FIG. 19, which shows a longitudinal section, only a part of it can be seen.

  As shown in FIGS. 14, 18, 19 and 22, the first component 21 extends from the bottom surface (rear end surface) 21b of the rear end side recess 21B to the bottom surface (front end surface 21a) of the front end side recess 21A. As described above, the central through hole 214 is formed along the central axis of the first component 21.

The central through hole 214 of the first component 21 and the central through hole 224 of the second component 22 constitute a central through hole of the irrigation member 20.
As shown in FIGS. 14, 16 to 19, and 22 to 25, the central tube 54 is inserted into the central through hole (214, 224) of the irrigation member 20. Inside the central tube 54, the lead wire 30L of the tip electrode 30 and the lead wire 35L of the temperature sensor are inserted.

  As shown in FIGS. 20 to 24, the outer peripheral surface of the first component 21 (straight barrel portion 213) can accommodate the lead wire 40L of the ring electrode 40 (first ring electrode from the tip) 4. The two storage grooves 215 are arranged and formed at equal angular intervals (90 ° intervals) along the outer periphery of the straight body portion 213.

Here, the width of the storage groove 215 is preferably 0.12 to 0.50 mm, and is 0.34 mm if a suitable example is shown.
Moreover, it is preferable that the depth of the storage groove 215 is 0.10-0.20 mm, and if it shows a suitable example, it will be 0.12 mm.

One of the four storage grooves 215 formed on the outer peripheral surface of the first component 21 (straight barrel portion 213) is a storage groove 225 formed on the outer peripheral surface of the second component 22 (straight barrel portion 223). Arranged on the same straight line, the lead wire 40L of the ring-shaped electrode 40 is housed in the housing groove 215 and the housing groove 225 of the second component 22.
As shown in FIG. 22, the lead wire 40L of the first ring electrode 40 from the tip passes through the storage groove 215 and the storage groove 225 (the shallow groove portion 225a, the inclined portion 225b, the deep groove portion 225c), and the catheter shaft 10 A connector (illustrated) is guided through the opening of the lumen 13 and enters the lumen 13 through the opening, passes through the lumen 13 of the catheter shaft 10 and the inside of the control handle 70, and is connected to the inside of the control handle 70 or the proximal end thereof. Is omitted). The lead wire 40L of the second ring-shaped electrode 40 from the tip is guided to the opening of the lumen 13 of the catheter shaft 10 through the storage groove 225 (shallow groove deep groove portion 225c).

The catheter shaft in which the irrigation member is located is not formed until the storage groove (the storage groove 215 in the first component 21 and the storage groove 225 in the second component 22) of the lead wire 40L is formed on the outer peripheral surface of the irrigation member 20. It is possible to mount the ring-shaped electrode 40 on the outer peripheral surface (region) of 10.
As a result, the distance between the tip electrode 30 and the first ring electrode 40 from the tip can be narrowed (for example, about 2 mm), and a desirable potential measurement can be performed between these electrodes. .

The first component 21 and the second component 22 constituting the irrigation member 20 are made of a molded body of an insulating resin or an insulating ceramic.
The first component 21 and the second component 22 are preferably made of a molded body obtained by a ceramic injection molding method (CIM).
According to the ceramic injection molding method, even a fine shape (for example, a fine shape having a thickness of about 60 μm) that cannot be formed by resin injection molding can be formed. The irrigation member 20 can be reliably molded.
Moreover, the ceramic molding obtained by the ceramic injection molding method has low thermal conductivity suitable as a constituent material of the irrigation member.
Further, the ceramic molded body by the ceramic injection molding method is excellent in insulation, and even when the irrigation member 20 made of this molded body has an edge, current is concentrated on the edge portion when the ablation catheter 100 is used (cauterization). And does not become hot.
As a suitable ceramic material constituting the irrigation member 20, it is preferable to use zirconia from the viewpoint of excellent molding processability and excellent biocompatibility.

The irrigation member 20 is configured by fitting a rear end side concave portion 21 </ b> B formed in the first component 21 and a front end side small diameter portion 221 of the second component 22.
In the fitting portion of the irrigation member 20, the bottom surface (rear end surface) 21b of the rear end side recess 21B of the first component 21 and the front end surface 22a of the second component 22 are separated by a distance of d ₂₁ -d _22. In the meantime, a jacket space partitioned by the inner peripheral surface of the rear end side recess 21B and the outer peripheral surface of the central tube 54 is defined, and this jacket space serves as a liquid storage space 24.

The storage space 24 formed in this way is a space for allowing the liquids from the eccentric flow paths 23, 23 to merge and uniformly distributing in the circumferential direction of the irrigation member 20. Since the storage space 24 has no circumferential partition, the liquid flowing into the storage space 24 can freely flow in the circumferential direction.
Here, the length (d ₂₁ -d ₂₂ ) of the storage space 24 is preferably 0.15 to 0.65 mm, and is 0.30 mm if a suitable example is shown.

  The irrigation member 20 configured as described above has two eccentrics formed inside the second component 21 so as to communicate with the distal-end-side passage forming lumens 11 of the catheter shaft 10 serving as a liquid passage. The first part 21 is a space communicating with the flow paths 23, 23 and the eccentric flow paths 23, 23 so that the liquid from the eccentric flow paths 23, 23 is uniformly distributed in the circumferential direction of the irrigation member 20. A liquid storage space 24 that does not have a partition wall in the circumferential direction formed at a fitting portion with the second component 22, communicates with the storage space 24, extends in the distal direction while inclining outward, and the irrigation opening 25 </ b> A. The eight branch channels 25 formed inside the first part so as to reach each of the eight parts, and the tip of the eight branch channels 25 continuously extending from each of the irrigation openings 25A in the tip direction. Formed in the portion (the reduced diameter portion 211 of the first part) It comes to have a guide groove 26 of the.

As shown in FIG. 19, the straight body 213 and the second part 22 (the distal-side small-diameter portion 221 and the straight-body portion 223) of the first component 21 constituting the irrigation member 20 are inserted into the distal-side recess of the catheter shaft 10 ( The eccentric flow paths 23 and 23 of the irrigation member 20 are communicated with the distal end flow path forming lumens 11 and 11 of the catheter shaft via the joint tubes 51 and 51, respectively. An irrigation member 20 is connected to the distal end side of the shaft 10.
Thereby, only the reduced diameter portion 211 and the large diameter portion 212 of the first component 21 appear as the external shape of the irrigation member 20.

  On the other hand, the tip electrode 30 is connected to the tip side of the irrigation member 20 by fitting the cylindrical portion 33 of the tip electrode 30 into the tip side recess 21A of the irrigation member 20 (first component 21).

  The tip electrode 30 connected to the tip side of the irrigation member 20 and constituting the ablation catheter 100 has a hemispherical tip bulging portion 31, a neck portion 32, and a cylindrical portion 33.

  The diameter of the tip bulging portion 31 of the tip electrode 30 is preferably 1.0 to 3.3 mm, more preferably 2.2 to 2.6 mm, particularly preferably 2.3 to 2.5 mm. An example is 2.36 mm.

Further, when the diameter of the tip bulging portion 31 (the maximum diameter of the tip electrode 30) is D1 and the tube diameter of the catheter shaft 10 is D2, the value of D1 / D2 is preferably 1.0 or more, and more preferably. Is 1.0 to 1.5, and 1.0 (D1 / D2 = 2.36 mm / 2.36 mm) is shown as a preferable example.
When the value of D1 / D2 is too small, it is difficult to perform efficient cauterization treatment with a catheter provided with such a tip electrode.
On the other hand, when the value of D1 / D2 is excessive, it becomes difficult to irrigate a sufficient amount of liquid onto the surface of such a tip electrode.

  Note that a sufficient amount of liquid can be irrigated with respect to the surface of the tip electrode 30 having a value of D1 / D2 of 1.0 or more because the branch flow path 25 of the irrigation member 20 is inclined outward. This is because the irrigation opening 25 </ b> A is positioned on the outer side as compared with the case where it is not inclined. Also in this point, it is meaningful to interpose the irrigation member 20.

In addition, a liquid guide groove 36 that is continuous with each of the guide grooves 26 of the irrigation member 20 is formed at the proximal end portion (neck portion 32) of the distal electrode 30.
By forming the guide groove 36, the liquid that has reached the proximal end portion of the distal electrode 30 through the guide groove 26 formed in the irrigation member 20 is guided (guided) to the distal end portion of the distal electrode 30. Accordingly, the liquid can be supplied to the entire surface of the tip electrode 30 including the tip bulge portion 31.
Since the guide groove 36 formed in the tip electrode 30 has a gentle R shape, an abnormal temperature rise does not occur in this portion even during cauterization.

  As described above, according to the ablation catheter 100 of the present embodiment, the central lumen 16 serving as the liquid channel in the non-flexible portion and the distal-side flow path forming lumen 11 serving as the liquid channel in the distal flexible portion 10A. , 11 is arranged so as to communicate with each of the fluids 11, 11, the liquid flowing through the central lumen 16 is divided into the two distal-end-side channel forming lumens 11, 11 and supplied to the irrigation member 20. be able to.

In the ablation catheter 100 of the present invention, the distal-side flow path forming lumens 11 and 11 (the liquid flow path in the distal flexible part 10A) in the distal flexible part 10A are formed eccentrically from the central axis of the catheter shaft 10. Therefore, the leaf spring 65 can be disposed on the distal end flexible portion 10A along this central axis.
Since the ablation catheter 100 in which a leaf spring is disposed as a deflection mechanism is provided with sufficient torsional rigidity to the distal end flexible portion 10A of the catheter shaft 10, a conventional catheter in which the leaf spring cannot be disposed (the entire area of the catheter shaft). Compared with a catheter in which a lumen serving as a liquid flow path is formed along the central axis of the shaft, the operability as a tip deflectable catheter and the flatness in the bending direction of the tip flexible portion are excellent. Become.

  Further, since the central lumen 16 serving as the liquid flow path is formed along the central axis in the non-flexible portion of the catheter shaft 10, the lumen serving as the liquid flow path is formed eccentrically over the entire area of the catheter shaft. A larger flow rate (amount of irrigation solution) than that of a conventional catheter can be secured, and a sufficient amount of liquid necessary for cooling or the like can be irrigated on the surface of the tip electrode 30.

  In addition, since the liquid flow path by the central lumen 16 is formed in the non-flexible portion of the catheter shaft 10, the lumen that becomes the liquid flow path is formed eccentrically from the central axis over the entire area of the catheter shaft. In addition, it is possible to reduce the risk of liquid leakage or blockage of the flow path when bent.

  Further, since the irrigation opening 25A is formed in the insulating irrigation member 20, and there is no edge in the conductive tip electrode 30, a part of the tip electrode 30 is used when the ablation catheter 100 is used (cauterization). An abnormal temperature rise (high temperature part) does not occur, and it is possible to prevent blood from coming into contact with such a high temperature part and forming a thrombus. In addition, since there is no need to form an opening in the tip electrode 30, a sufficient surface area for cauterization can be ensured, and efficient cauterization treatment can be performed.

Furthermore, according to the ablation catheter 100 of this embodiment, the liquid is ejected (irrigated) from the eight irrigation openings 25A arranged at the distal end portion of the irrigation member 20 onto the surface of the distal electrode 30. A sufficient amount of liquid can be brought into contact with the surface of the electrode 30. Moreover, the liquid sprayed onto the surface of the tip electrode 30 flows along the surface of the tip electrode 30 from the base end portion (neck portion 32) of the tip electrode 30 toward the tip portion (tip bulge portion 31). .
Therefore, the ablation catheter 100 has an excellent cooling effect on the surface of the tip electrode 30 and sufficient blood around the tip electrode 30 as compared with a conventionally known catheter in which an irrigation opening is formed in the tip electrode. By further stirring and diluting, a more excellent thrombus formation inhibitory effect is exhibited.
In addition, since the eight irrigation openings 25A are arranged at equiangular (45 °) intervals along the outer periphery of the irrigation member 20, it is possible to irrigate the surface of the tip electrode 30 over the entire region in the circumferential direction (360 °). it can.

Further, in the distal end flexible portion 10A of the catheter shaft 10, two distal end side passage forming lumens 11 and 11 serving as liquid passages, two lumens 12 and 12 serving as insertion passages for the pulling wires 61 and 62, and a ring Since the two lumens 13 and 13 serving as insertion paths for the lead wires of the electrode 40 are formed at eccentric positions, a leaf spring that could not be arranged by a conventional irrigation catheter having an irrigation member 65 can be disposed along the central axis in the distal flexible portion 10A of the catheter shaft 10.
The ablation catheter 100 in which the leaf spring 65 is disposed is excellent in operability by providing sufficient torsional rigidity to the distal end flexible portion 10A of the catheter shaft 10.

  Furthermore, inside the irrigation member 20, there are eight liquid storage spaces 24 that do not have partition walls in the circumferential direction, and eight channels that communicate with the storage space and extend in the distal direction while inclining outward to reach each of the irrigation openings 25A. Since the branch flow path 25 is formed, the liquid that has reached the storage space 24 through the eccentric flow paths 23, 23 is arranged to be uniformly distributed in the circumferential direction in the storage space 24. Since each of the eight branch channels 25 is ejected (irrigated) from the irrigation opening 25A, the amount of liquid supplied from the catheter shaft 10 to the irrigation member 20 varies in the circumferential direction (flexible tip portion). Although there is a variation in the circumferential direction due to the eccentricity of the two distal-end-side passage forming lumens 11 and 11 serving as liquid passages due to the leaf spring 65 disposed at 10A. Equiangular ( There is no variation in the amount of liquid ejected between the eight irrigation openings 25A arranged at 5 ° intervals, and it becomes possible to perform uniform ejection (irrigation) in the circumferential direction of the irrigation member 20, and the tip electrode 30 surfaces can be uniformly irrigated over the entire circumferential area (360 °).

Further, the rear end side recess 21B (the rear end shape of the first part) formed in the first part 21 and the front end side small diameter portion 221 (the front end shape of the second part) of the second part 22 are fitted. Thus, the irrigation member 20 is configured, and the cylindrical portion 33 of the tip electrode 30 (the rear end shape of the tip electrode) and the tip side recess 21A of the first component 21 (the tip shape of the first component) are fitted. Thus, the tip electrode 30 can be connected to the tip side of the irrigation member 20.
Thus, by comprising the irrigation member 20 by two parts, the problem of the undercut resulting from the shape of the storage space 24 can be avoided, the eccentric flow paths 23 and 23, the storage space 24, and 8 It becomes possible to obtain the irrigation member 20 in which the branch channel 25 of the book is formed by molding.

  Furthermore, since each of the branch channels 25 formed inside the irrigation member 20 (first component 21) is formed so as to be inclined outward, the tip electrode (D1 / D2 having a value of 1 / D2 having a certain size is 1). The surface of the tip electrode 30) which is 0.0 can be sufficiently irrigated.

Furthermore, a liquid guide groove 26 extending in the distal direction continuously to each of the branch flow paths 25 is formed at the distal end portion of the irrigation member 20 (first component 21), so that it is ejected from the irrigation opening 25A. The liquid to be guided can be reliably guided (guided) toward the tip electrode 30.
Further, a liquid guide groove 36 that is continuous with each of the guide grooves 26 of the irrigation member 20 is formed on the surface of the proximal end portion of the tip electrode 30, so that it passes through the guide groove 26 formed in the irrigation member 20. The liquid that has reached the proximal end portion of the tip electrode 30 can be guided to the tip portion of the tip electrode 30, whereby the liquid can be supplied to the entire surface of the tip electrode 30.

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to these, A various change is possible.
For example, the number of branch channels (irrigation openings) in the irrigation member does not have to be 8, and can be appropriately selected within a range of 4 to 12, for example.
Further, the number of lumens (the number of eccentric flow paths in the irrigation member) serving as the liquid flow path of the catheter shaft may not be 2, but may be 1 or 3 or more. However, the present invention is effective when a catheter shaft having a small number of lumens serving as liquid channels is used.
Also, the internal structure of the catheter shaft is not particularly limited as long as the lumen serving as the liquid flow path is formed eccentrically at the distal end flexible portion.
The shape of the tip electrode is not particularly limited, and may be a shell shape.

DESCRIPTION OF SYMBOLS 100 Ablation catheter 10 Catheter shaft 101 Front end side multi-lumen tube 102 Rear end side multi-lumen tube 103 Outer skin member 10A Front end flexible part 11 Front end side flow path forming lumen 12 Lumen (insertion passage of tension wire)
13 Lumen (Ring electrode lead wire insertion path)
14 lumens (lead electrode lead-in passage)
15 lumen (temperature sensor lead wire insertion path)
16 Central lumen 171 to 178 Sub-lumen 21 First part 211 Reduced diameter part 212 Large diameter part 213 Straight body part 214 Central through hole 215 Lead wire storage groove 21A Tip side recess 21a Bottom face (tip face) of tip side recess 21A
21B Rear end side recess 21b Bottom surface of rear end side recess 21B (rear end surface)
22 Second part 221 Tip side small diameter part 223 Straight body part 224 Central through hole 225 Lead wire receiving groove 226 Pulling wire tip groove receiving groove 22a Tip side small diameter part tip surface 23 Eccentric flow path 231 Stepped part 24 Liquid flow Storage space 25 Branch channel 25A Irrigation opening 26 Liquid guide groove 30 Lead electrode 30L Lead electrode lead wire 31 Tip bulge portion 32 Neck portion 33 Cylindrical portion 35L Temperature sensor lead wire 36 Liquid guide groove 40 Ring shape Electrode 40L Ring-shaped electrode lead wire 51 Joint tube 54 Central tube 61 Tensile wire 62 Tensile wire 65 Leaf spring 70 Channel branch member 71 Tensile wire insertion path 72 Tensile wire insertion path 73 Liquid branch channel 74 Tip electrode Lead wire and temperature sensor lead wire passage 75 Ring electrode lead wire passage 7 Rear end reduced diameter portion 70A Front end surface 71A Insertion passage opening 72A Insertion passage opening 731A Branch passage opening 732A Branch passage opening 74A Insertion passage opening 75A Insertion passage opening 70B Rear end surface 71B Insertion passage opening 72B Insertion passage opening 73B Branch passage opening 74B Insertion passage opening 75B Insertion passage opening 80 Coil tube 700 Control handle 705 Rotating plate 800 Liquid injection tube

Claims (6)

A catheter shaft having a distal end flexible portion and having a lumen serving as a liquid flow path; a leaf spring disposed along a central axis of the catheter shaft at the distal end flexible portion of the catheter shaft; An insulating irrigation member connected to the distal end side of the catheter shaft, and a distal electrode connected to the distal end side of the insulating irrigation member,
In the insulating irrigation member, a plurality of irrigation openings for irrigating the surface of the tip electrode with liquid supplied from the catheter shaft are arranged at equiangular intervals along the outer periphery of the insulating irrigation member. ,
In the catheter shaft, at least two lumens serving as liquid flow paths are formed eccentrically with respect to the central axis at the distal end flexible portion, and the catheter is located on the proximal end side of the distal end flexible portion. In the non-flexible portion of the shaft, a single central lumen serving as a liquid flow path is formed along the central axis,
The catheter shaft is provided with a flow path branching member that communicates a central lumen that becomes a liquid flow path in the non-flexible portion and each lumen that becomes a liquid flow path in the distal flexible portion. A featured electrode catheter.   2. The electrode catheter according to claim 1, wherein two lumens serving as liquid flow paths at the distal end flexible portion of the catheter shaft are formed so as to face each other with the central axis interposed therebetween. The tip flexible portion is configured by a tip-side multi-lumen tube in which a plurality of lumens including two lumens serving as a liquid flow path are formed while the leaf spring is disposed.
The non-flexible portion includes a rear end side multi-lumen tube on which the central lumen and a plurality of sub-lumens formed around the central lumen are formed inside a coil tube that makes the non-flexible portion inflexible. Composed by being inserted,
The flow path branch member is disposed between the front end side multi-lumen tube and the rear end side multi-lumen tube,
An opening corresponding to the opening of the lumen of the front end multi-lumen tube is formed on the front end surface of the flow path branch member, and the rear end side multi-lumen tube is formed on the rear end surface of the flow path branch member. The electrode catheter according to claim 2, wherein an opening corresponding to the opening of the lumen is formed.   The electrode catheter according to claim 3, wherein the flow path branching member is formed with a rear-end-side reduced diameter portion that is inserted into the coil tube.   The electrode catheter according to claim 3 or 4, wherein the flow path branching member, the front end side multi-lumen tube, and the rear end side multi-lumen tube are connected via a joint tube. . Inside the insulating irrigation member, at least two eccentric flow paths communicating with each of the lumens serving as liquid flow paths in the distal flexible portion of the catheter shaft,
A space communicating with the eccentric flow path, and a liquid storage space having no partition wall in the circumferential direction so that the liquid from the eccentric flow path is uniformly distributed in the circumferential direction of the insulating irrigation member; ,
6. A plurality of branch passages communicating with the storage space and extending in a distal direction while being inclined outward to reach each of the plurality of irrigation openings are formed. The electrode catheter according to any one of the above.

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