WO2016039394A1 - Ablation catheter - Google Patents

Abstract

　Provided is an ablation catheter that can simultaneously perform ablation in a plurality of treatment sites, that can prevent shifts in the position of heating elements that are positioned at treatment sites when performing ablation, and that can reduce surgery duration and efficiently perform thermal ablation while adequately preventing the occurrence of stenosis after surgery. This ablation catheter (100) has an elongate shaft (50), expanding deformation parts (10, 20, 30) that are provided to the tip side of the shaft and that can be expanded and contracted and deformed, and at least two heating elements (80) that are provided to a plurality of expanding deformation parts and that thermally affect living tissue. Each of the expanding deformation parts is provided at a different position in the longitudinal direction of the shaft, and is formed so as to be individually capable of expanding deformation in a different direction that intersects with the axial direction of the shaft.

Description

Ablation catheter

The present invention relates to an ablation catheter used as a medical device for ablating living tissue.

Conventionally, ablation treatment has been carried out as a method of locally treating a living organ affected by a predetermined disease and treating it. Ablation treatment is a treatment method for recovering symptoms such as dysfunction caused by a disease by applying thermal energy or the like to living tissue to cauterize or necrotize the diseased part. The ablation treatment has been tried to be applied to, for example, myocardial cautery for treating tachyarrhythmia and renal sympathetic nerve ablation (renal sympathetic nerve ablation) which has been attracting attention in recent years.

The ablation treatment is performed using a medical device called an ablation catheter. Ablation catheters generally include a thermal element for applying thermal energy or the like to living tissue, and a long shaft portion for delivering the thermal element to a desired position in the living body. . During the treatment, the surgeon refers to an image around the diseased site acquired in advance by X-ray imaging or the like, operates the ablation catheter at hand, and performs an operation of positioning the thermal element in the living tissue that becomes the treatment target site. And after positioning, thermal energy etc. are provided to a biological tissue from a thermal element, and the treatment is completed.

For example, when there are a plurality of treatment target sites, the thermal element must be positioned and arranged with respect to each treatment target site every time treatment is performed. The burden on the patient accompanying the prolonged time becomes a problem. In particular, when performing renal sympathetic nerve ablation, the thermal element is positioned with respect to the treatment target site in order to perform treatment on a plurality of renal sympathetic nerves that run irregularly on the outer surface of the renal artery. Work becomes even more complicated. If the treatment is performed multiple times with a narrower interval along the circumferential direction of the same inner peripheral surface of the renal artery (the direction of the inner peripheral surface located on the same orthogonal cross section), it is necessary to position the thermal element. Although it may be possible to efficiently treat the renal sympathetic nerve without saving time, when such a treatment is performed, the treated site is locally concentrated along the circumferential direction of the same inner peripheral surface. Therefore, there is concern about the formation of a stenosis due to the effects of tissue degeneration or necrosis due to ablation, swelling of the vascular wall of the renal artery, and the like.

In relation to the above problems, for example, in Patent Document 1 below, a plurality of thermal elements (electrodes) are arranged by shifting the position in the axial direction of the catheter tip formed in a spiral shape. There has been disclosed an ablation catheter capable of simultaneously performing treatment on a site and preventing the treated sites from overlapping each other in the extending direction of the renal artery and the direction of the inner peripheral surface.

Japanese Patent Application Laid-Open No. 2012-110738

The conventional ablation catheter is configured such that the distal end of the catheter formed in a spiral shape can be passively (flexibly) deformed in the extending direction in order to make the treatment range variable in the extending direction of the renal artery. . For this reason, the thermal element arranged at the distal end portion of the catheter is not held with a sufficient holding force with respect to the treatment target site, and positional displacement can easily occur with deformation of the distal end portion of the catheter. When the thermal element is displaced, ablation is performed on an unintended part and insufficient cauterization occurs, so that ablation must be performed again. However, it is not easy to accurately reposition each thermal element arranged at the distal end of the spiral catheter with respect to the target treatment target site while avoiding the already treated site. . For this reason, when the conventional ablation catheter is used, there is a problem that problems such as a prolonged treatment time and a half of the therapeutic effect and problems such as formation of a stenosis are likely to occur.

Therefore, the present invention has been made to solve the above-described problems, and enables ablation to be performed simultaneously on a plurality of treatment target sites, and further, positioning relative to the treatment target sites when performing ablation. It is possible to prevent the occurrence of misalignment in each thermal element, and it is preferable to prevent the formation of a constricted part with the treatment while shortening the treatment time and efficient thermal cauterization. An object of the present invention is to provide a possible ablation catheter.

An ablation catheter that achieves the above-described object is provided in a long shaft portion, a plurality of expansion deformation portions that are provided on the distal end side of the shaft portion and can be expanded and contracted, and a plurality of expansion deformation portions. Two or more thermal elements that have a thermal effect on the living tissue, and each of the plurality of expansion deformable portions is disposed at a different position in the axial direction of the shaft portion, and These are ablation catheters that can be individually expanded and deformed in different directions intersecting the axial direction of the shaft portion.

In the ablation catheter configured as described above, a plurality of expansion deformed portions where at least two or more thermal elements are disposed are disposed at different positions in the axial direction of the shaft portion, and each of the expansion deformable portions is a shaft. Because it can be expanded and deformed in different directions intersecting the axial direction of the part, when the expanded deformed part is expanded and deformed in the living organ, it is treated with an appropriate interval between the thermal elements. It can be placed at the target site. Further, since each of the expansion deforming portions is individually expanded and deformed and held in a state where each thermal element is positioned with respect to the treatment target site, it is preferable that the thermal element is displaced during the treatment. Can be prevented. Thus, treatment can be performed on a plurality of treatment target parts at the same time, and inadvertent displacement of the thermal element can be prevented, so that the treatment time can be shortened and efficient. It is possible to suitably prevent the formation of a stenosis part with the treatment while achieving proper thermal ablation.

If at least one thermal element is provided in each of the plurality of expansion deformation portions, it becomes possible to perform ablation using each thermal element provided in each expansion deformation portion. The procedure can be performed more efficiently.

If the shaft portion is configured by a tubular member in which a plurality of slits are formed, and the plurality of expansion deformable portions are configured by an easily deformable portion in which expansion deformation is induced by the slits in the tubular member, it is relatively simple. By processing a tubular member having such a structure, the expanded deformable portion can be easily manufactured, so that the manufacturing cost of the ablation catheter can be reduced and the manufacturing operation can be simplified.

If a plurality of sets of easily deformable portions formed in pairs at opposite positions in the circumferential direction of the tubular member are provided at different positions in the axial direction of the tubular member, each thermal element is applied to a plurality of treatment target sites. It is possible to easily form an expanded deformable portion having multi-directional deformability that can be suitably positioned and arranged in the tubular member.

The inner tube further includes an inner tube through which the tubular member is inserted. When the inner tube has a guide wire lumen through which the guide wire can be inserted, the inner tube is used when a plurality of expansion deformable portions are delivered to the treatment target site. It is possible to secure a guide wire lumen.

If the extended deformation part is made of a linear member that is pre-shaped so as to divide a plane intersecting the axial direction of the shaft part around the shaft part when the extended deformation part is expanded, the expansion deformation part Since it becomes possible to apply a pressing force along the surface direction in which the plane defined by the surface spreads, it becomes possible to stably hold the thermal element arranged in each expansion deformable portion with respect to the treatment target site. . Thereby, it can prevent more reliably that position shift generate | occur | produces in a thermal element.

If the first to third expansion / deformation parts that divide planes intersecting with each other at an angle of 60 ° with each other in the circumferential direction of the shaft part are provided, each of the thermal elements arranged in the first to third expansion / deformation parts is Since it is possible to dispose the treatment portion at an appropriate interval in the axial direction and the circumferential direction of the shaft portion, it is possible to further reduce the risk of forming a stenosis portion associated with the treatment.

At least one of the plurality of expansion / deformation portions is disposed so as to be movable in the axial direction of the shaft portion, and the shaft portion is provided with a stopper for limiting the amount of movement of the expansion / deformation portion. For example, when a medical device such as a guide sheath is used to deliver the expanded deformable portion to the treatment target site, the expansion and contraction deformation of the expanded deformable portion is assisted by transmitting a pushing / pulling force from the guide sheath or the like to the expanded deformable portion. This makes it possible to smoothly move the expansion deforming portion into and out of the guide sheath.

If a plurality of thermal elements are arranged at different positions in the circumferential direction of the shaft part for each expansion deformation part, with respect to the inner peripheral surface located on the same orthogonal cross section of the living organ including the treatment target site Because it is possible to place multiple thermal elements at appropriate intervals, it is possible to further reduce the risk of stenosis due to the treatment while further shortening the treatment time Become.

If each of the plurality of thermal elements arranged in the plurality of expansion deformable portions is arranged at different positions in the circumferential direction of the shaft portion, an appropriate interval is secured in the extending direction of the living organ including the treatment target site. However, since it becomes possible to arrange each thermal element with respect to the treatment target site by securing an appropriate interval on the inner peripheral surface located on the same orthogonal cross section of the living organ, The risk of formation can be greatly reduced.

If each of the plurality of thermal elements is arranged at an equal interval in the circumferential direction of the shaft portion, each thermal element is equally spaced on the inner peripheral surface located on the same orthogonal cross section of the living organ. Since it becomes possible to arrange | position, it becomes possible to further reduce the risk of formation of the stricture part accompanying a treatment.

A sheath in which a plurality of expansion deformable portions can be inserted, and by operating the sheath forward and backward in the axial direction, the insertion of the plurality of expansion deformable portions into the sheath and the projection of the plurality of expansion deformable portions from the distal end opening of the sheath are operated. Each of the plurality of expansion / deformation parts contracts and deforms as it is inserted into the sheath, and expands and deforms as it protrudes from the distal end opening of the sheath. By doing so, until the expansion deforming portion is delivered to the treatment target site, the expansion deformation portion can be contracted and held in the sheath, and the thermal element is arranged with respect to the treatment target region. At this time, since the expansion deformation can be performed by a simple operation by simply protruding the expansion deformation portion from the sheath, the ablation catheter can be configured as a user-friendly device.

1 is a perspective view schematically showing a treatment system including an ablation catheter according to a first embodiment of the present invention. It is a figure which shows the ablation catheter which concerns on 1st Embodiment. FIG. 3 is a sectional view taken along line 3A-3A shown in FIG. 4A and 4B are views showing a main part of the ablation catheter according to the first embodiment, wherein FIG. 4A is an overview perspective view showing a state in which an expansion deforming part included in the ablation catheter is expanded, and FIG. 4B is an expansion deformation. It is a general-view perspective view which shows the state which the part contracted. It is a general-view perspective view which expands and shows the front-end | tip part of the ablation catheter which concerns on 1st Embodiment. FIG. 6 is a view showing a cross section of each part of the ablation catheter according to the first embodiment, (A) is a cross sectional view taken along line 6A-6A shown in FIG. 5, and (B) is a 6B shown in FIG. FIG. 6C is a cross-sectional view taken along line 6C-6C shown in FIG. FIG. 7 is a view showing a cross section of each part of the ablation catheter according to the first embodiment, (A) is a cross sectional view taken along line 7A-7A shown in FIG. 5, and (B) is 7B shown in FIG. FIG. 7C is a cross-sectional view taken along line 7C-7C shown in FIG. FIGS. 8A and 8B are diagrams for explaining the configuration of the expanded deformable portion, where FIG. 8A is a plan view showing the expanded deformable portion in the contracted state, and FIG. 8B shows the expanded deformable portion in the expanded state. It is a top view. FIG. 9 is a diagram for explaining an example of use of the ablation catheter according to the first embodiment. FIG. 9A is a diagram illustrating a case where a guiding catheter for delivering an ablation catheter to a treatment target site is introduced into a renal artery. FIG. 5B is a cross-sectional view schematically showing a state when the ablation catheter is delivered to the treatment target site using the guiding catheter. FIG. 10 is a diagram for explaining an example of use of the ablation catheter according to the first embodiment, and FIG. 10A is a schematic view showing a state in which an expansion deforming portion included in the ablation catheter is expanded in the renal artery. Sectional drawing shown, (B) is a perspective sectional view schematically showing a state when the expansion deformation portion is expanded. 11A and 11B are diagrams illustrating the positional relationship between the treatment target region and each thermal element. FIG. 11A is a cross-sectional view taken along the line 11A-11A shown in FIG. 10A, and FIG. FIG. 10A is a cross-sectional view taken along line 11B-11B shown in FIG. 10A, and FIG. 10C is a cross-sectional view taken along line 11C-11C shown in FIG. It is a figure which shows the ablation catheter which concerns on the 1st modification of 1st Embodiment. FIG. 13 is a view for explaining the configuration of an ablation catheter according to a first modification of the first embodiment, and FIG. 13 (A) is a cross-sectional view taken along the line 13A-13A shown in FIG. FIG. 13B is a cross-sectional view taken along line 13B-13B shown in FIG. FIG. 14 is a view for explaining an ablation catheter according to a second modification of the first embodiment, and FIG. 14A is an overview perspective view showing a main part of the ablation catheter according to the second modification; B) is a plan view showing an extended deformation portion. FIG. 15 is a view for explaining an ablation catheter according to a third modification of the first embodiment, and FIG. 15A is an overview perspective view showing a main part of the ablation catheter according to the third modification; B) is a plan view showing an extended deformation portion. FIG. 16 is a view for explaining an ablation catheter according to a fourth modification of the first embodiment, another modification, and yet another modification. FIG. 16A is an ablation according to the fourth modification. An outline perspective view showing the principal part of a catheter, (B) is an outline perspective view showing the principal part of an ablation catheter concerning other modifications, and (C) shows the principal part of an ablation catheter concerning another modification. FIG. FIG. 17 is a view for explaining an ablation catheter according to a fifth modification of the first embodiment, and FIG. 17A is an overview perspective view showing a main part of the ablation catheter according to the fifth modification; B) and (C) are schematic perspective views showing a state when the expansion deforming portion is moved. It is a general-view perspective view which expands and shows the front-end | tip part of the ablation catheter which concerns on the 5th modification of 1st Embodiment. It is a figure which shows the cross section of each part of the ablation catheter which concerns on the 5th modification of 1st Embodiment. It is a figure which shows the ablation catheter which concerns on 2nd Embodiment of this invention. FIG. 21 is a cross-sectional view taken along line 21A-21A shown in FIG. FIG. 22 is a view showing the main part of the ablation catheter according to the second embodiment, (A) is an overview perspective view showing a state before the expansion deforming portion provided in the ablation catheter is expanded, (B) is It is a general-view perspective view which shows the state which the expansion deformation | transformation part expanded. FIG. 23 is a diagram illustrating the positional relationship between a treatment target site and each thermal element when using the ablation catheter according to the second embodiment, and FIG. 23 (A) is a line 23A-23A shown in FIG. 22 (B). (B) is a virtual cross-sectional view corresponding to the line 23B-23B shown in FIG. 22 (B). FIG. 24 is a diagram for explaining an ablation catheter according to a modification of the second embodiment, in which (A) is an overview perspective view showing a main part of the ablation catheter according to the modification, and (B) is It is a side view of the principal part of the ablation catheter of a modification.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, the following description does not limit the meaning of the technical scope and terms described in the claims. In addition, the dimensional ratios in the drawings are exaggerated for convenience of explanation, and may differ from actual ratios.

<First Embodiment>
As shown in FIG. 10 (A), the ablation catheter 100 according to this embodiment is for ablating (cauterizing) the renal sympathetic nerve RN that travels around the outer periphery of the renal artery RA that branches from the aorta and goes to the kidney R. It is configured as a medical device. In the illustrated example, the state when applied to the treatment for the right renal artery is shown, but it can also be applied to the treatment for the left renal artery in the same manner as the right renal artery.

As shown in FIGS. 1, 2, and 4, the ablation catheter 100 generally includes an elongated shaft portion 50 and a plurality of expansion deformable portions 10, 20, 30 disposed on the distal end side of the shaft portion 50. And a plurality of thermal elements 80a, 80b, 80c, 80d, 80e, 80f arranged in each of the expansion deformable portions 10, 20, 30 (for convenience of explanation, each of the thermal elements 80a to 80f needs to be individually described. Except for the case, it is simplified and described as “thermal element 80”).

In the description of the specification, the side of the ablation catheter 100 that is inserted into the living body is referred to as the distal end side, and the hand operating unit 90 side provided in the ablation catheter 100 is referred to as the proximal end side. The distal end means a predetermined range from the distal end to the proximal end, and does not mean only the distal end. Moreover, the X-axis attached | subjected in the figure shows the axial direction (extension direction) of the shaft part 50 of the ablation catheter 100, the Y-axis shows the depth direction, and the Z-axis shows the height direction. The axis orthogonal cross section in the specification means a YZ plane orthogonal to the shaft portion 50.

The configuration of each part of the ablation catheter 100 will be described.

The thermal element 80 included in the ablation catheter 100 receives electrical energy from the energy supply device 110 shown in FIG. 1 and generates heat to ablate the living tissue. Each of the expansion deformable portions 10, 20, and 30 has a function of holding the thermal element 80 firmly against the treatment target site when ablating the living tissue via the thermal element 80. As shown in FIG. 4, the expansion deformable portions 10, 20, and 30 are installed with their positions shifted in order from the distal end side of the shaft portion 50 so that they are arranged at different positions in the axial direction of the shaft portion 50. ing. Hereinafter, for convenience of explanation, the first expansion deformation unit 10, the second expansion deformation unit 20, and the third expansion deformation unit 30 are referred to in order from the expansion deformation unit arranged on the forefront side.

As shown in FIGS. 1 and 2, a hand operation unit 90 is provided on the proximal end side of the ablation catheter 100. A connector 96 is attached to the proximal end portion of the hand operation unit 90. The connector 96 is configured to be connectable to and disconnectable from the electrical connector 112 provided in the electrical cable 111 for supplying electrical energy to the thermal element 80. As shown in FIGS. 4A and 5, each of the thermal elements 80 is electrically connected to predetermined lead wires 70a to 70f (for convenience of explanation, the lead wires 70a to 70f are individually shown). In the drawings other than Fig. 5, the lead wires 70a to 70f, the tubes 40 covering the lead wires 70a to 70f, and the covering material are simplified. The detailed illustration of 41 is omitted). The lead wire 70 is attached to the connector 96 at its proximal end. When each of the thermal elements 80 is connected to the electrical cable 111 via the connector 96 and the electrical connector 112, the thermal element 80 becomes ready to be energized.

The energy supply device 110 supplies high-frequency electric energy for ablating the living tissue to the thermal element 80 via the electric cable 111. The energy supply device 110 incorporates a CPU having a function as a control unit, and can automatically control the heating temperature or the like by the heat element 80. The electric energy to be supplied is set to, for example, 0.1 W to 8.0 W, but is not limited to this value. Note that by providing the ablation catheter 100 with a temperature measuring unit made of a thermocouple or the like, the heating temperature by the thermal element 80 can be feedback controlled based on the temperature of the living tissue measured by the temperature measuring unit. It is.

As shown in FIG. 4 (A), two thermal elements 80 are arranged for each expansion deformation portion. Lead wires 70a and 70b are connected to the thermal elements 80a and 80b arranged in the first expansion deformable portion 10, respectively. Lead wires 70c and 70d are connected to the thermal elements 80c and 80d arranged in the second extended deformation portion 20, respectively. Lead wires 70e and 70f are connected to the thermal elements 80e and 80f arranged in the third expansion deformable portion 30, respectively. Accordingly, by individually supplying electric energy to the thermal elements 80a to 80e via the lead wires 70a to 70f, it is possible to individually control the ablation performed and stopped by the thermal elements 80a to 80e. . The operation control of each of the thermal elements 80a to 80e can be controlled by, for example, a CPU incorporated in the energy supply apparatus 110.

The thermal element 80 provided in the ablation catheter 100 is configured as a monopolar electrode. For this reason, as shown in FIG. 1, the counter electrode 120 is used when performing a treatment using the ablation catheter 100. The counter electrode plate 120 is electrically connected to the energy supply device 110. When performing treatment, the counter electrode plate 120 is attached to the body surface of a treatment subject (patient or the like), and a pseudo current circuit is formed between the thermal element 80, the treatment subject and the counter electrode plate 120. Thereby, it becomes possible to energize the living tissue of the treatment target site. The thermal element 80 can be configured by, for example, a known electrode tip for ablation configured to generate heat when energized. As shown in FIG. 1, the energy supply device 110, the counter electrode 120, and the ablation catheter 100 constitute a treatment system for performing an ablation treatment.

As shown in FIG. 2, the ablation catheter 100 is provided with a sheath 60 into which the respective expanded deformable portions 10, 20, and 30 can be inserted. When inserting the ablation catheter 100 into the living body, the sheath 60 prevents the expansion deforming portions 10, 20, and 30 from being inadvertently expanded and deformed so that the insertion operation can be performed smoothly. Provided.

As shown in FIG. 2, the sheath 60 is arranged such that the base end portion 63 is inserted into the hand operation unit 90. Further, the base end portion 63 is connected to a predetermined moving member 93. The sheath 60 is configured to be able to move forward and backward as the moving member 93 moves along the axial direction.

The moving member 93 is movably held inside the hand operation unit 90, and is moved forward and backward by a gear 92 used in combination with the moving member 93. The moving member 93 is formed with a tooth portion 93 a that meshes with the gear 92. The moving member 93 and the gear 92 constitute a rack and pinion mechanism. An operation member 91 for operating the rotation of the gear 92 is assembled to the gear 92. The upper end portion of the operation member 91 is disposed so as to be exposed from the opening portion 94 formed on the upper surface side of the hand operation portion 90. When the operation member 91 is operated with a finger or the like and the gear 92 is rotated, the moving member 93 moves forward and backward in conjunction with the rotation. When the moving member 93 moves forward and backward, the sheath 60 connected to the moving member 93 moves forward and backward according to the movement of the moving member 93. Specifically, when the operation member 91 is rotated in the direction of the arrow r1, the sheath 60 advances toward the distal end side as indicated by the arrow a1, and when the operation member 91 is rotated in the direction of the arrow r2, the sheath 60 is moved to the arrow direction. As shown by a2, it moves backward toward the base end side.

When the sheath 60 is advanced by a predetermined distance, each of the expanded deformable portions 10, 20, 30 is covered with the sheath 60 and accommodated inside the sheath 60. On the other hand, when the sheath 60 is retracted by a predetermined distance from the state where each of the expansion deformable portions 10, 20, 30 is accommodated in the sheath 60, each expansion deformation is caused from the distal end opening 61 a formed in the distal end portion 61 of the sheath 60. The parts 10, 20, and 30 protrude. As will be described later, each of the expansion deformable portions 10, 20, 30 is configured to be capable of self-expanding deformation with the protrusion from the sheath 60, so that the expansion deformation at the same time as the protrusion from the distal end opening 61 a of the sheath 60 is performed. To start. As shown in FIG. 2, the shaft portion 50 to which each of the expansion deformable portions 10, 20, and 30 is attached is fixed to a connector 96 whose base end portion 53 is disposed at the base end portion of the hand operating portion 90. Yes. For this reason, each expansion deformation part 10, 20, 30 does not move forward / backward in conjunction with the operation of the operation member 91.

The material of the material constituting the sheath 60 is not particularly limited, and for example, a resin material generally used for a guiding catheter or the like can be used. Examples include polyethylene, polypropylene, ethylene-propylene copolymers, polyolefins such as ethylene-vinyl acetate copolymers, thermoplastic resins such as soft polyvinyl chloride, various rubbers such as silicone rubber and latex rubber, polyurethane elastomers, Various elastomers such as polyamide elastomer and polyester elastomer, and crystalline plastics such as polyamide, crystalline polyethylene, and crystalline polypropylene can be used. Further, a mesh structure knitted from stainless steel or the like can be inserted into the sheath 60 as a reinforcing body.

3, the sheath 60 includes a guide wire lumen 66 through which the guide wire 130 is inserted, and a lumen 67 through which the shaft portion 50 is inserted. As shown in FIG. 2, a port 95 into which the guide wire 130 can be introduced is provided on the proximal end side of the hand operation unit 90. The guide wire 130 introduced from the port 95 is inserted through the guide wire lumen 66 of the sheath 60 along the axial direction. That is, the ablation catheter 100 is configured as a so-called over-wire type catheter device.

As shown in FIG. 3, each of the lead wires 70 is wired along the outer peripheral surface of the shaft 50 in the lumen 67 of the sheath 60. Moreover, the predetermined tube 40 is arrange | positioned so that the outer periphery of the lead wire 70 may be covered so that each lead wire 70 may not be scattered. As the tube 40, for example, a tube made of a heat-shrinkable resin material having electrical insulation can be used. In a state where the lead wire 70 is disposed in the tube 40, the lead wire 70 is prevented from being displaced from the outer peripheral surface of the shaft 50 by applying heat from the outer surface of the tube 40 to be contracted. In addition, when the shaft part 50 is a metal member, the shaft part 50 can be coat | covered with what was comprised with the heat-shrinkable resin material provided with electrical insulation, for example. As a result, each of the lead wires 70a to 70f is not directly in contact with the shaft portion 50 due to the resin material having electrical insulation, so that it is possible to more reliably prevent leakage from the lead wires 70a to 70f through the shaft portion 50. It is possible to prevent this, and the safety during use can be further enhanced.

As shown in FIGS. 4A and 5, each of the lead wires 70a to 70f led out from the distal end opening 61a of the sheath 60 has, for example, the expansion deformable portions 10, 20, 30 along the shaft portion 50. Each of the thermal elements 80a to 80f can be wired so as to be along the outer surface.

Further, as shown in FIGS. 4A and 4B, each of the first expansion deformation portion 10, the second expansion deformation portion 20, and the third expansion deformation portion 30 is provided for each of the expansion deformation portions 10, 20, 30. It is fixed to the shaft portion 50 at two locations, the distal end portion and the proximal end portion.

As shown in FIG. 5, each of the lead wires 70a to 70f is covered with a covering material 41 other than the end portions (tip portions) connected to the thermal elements 80a to 80f. Similarly, a covering material 41 is covered in the region where the third expansion deforming portion 30 and the region where the second expansion deforming portion 20 is arranged in the shaft portion 50. As the covering material 41, for example, a material made of a known resin material having electrical insulating properties similar to the tube 40 can be used.

As shown in FIG. 6A, the lead wires 70a to 70e are spaced apart from each other by a predetermined distance in the circumferential direction along the outer peripheral surface of the shaft portion 50 on the proximal end side with respect to the third expansion deformable portion 30. Arranged. Each lead wire 70 a to 70 f is covered with a tube 40.

As shown in FIG. 7A, when the lead wire 70e connected to the thermal element 80e is wired to the vicinity of the proximal end portion of the third expansion deformable portion 30, the lead wire 70e branches off from the shaft portion 50, 3 It is wired to the heat element 80e side along the outer peripheral surface of the extended deformation portion 30. Although not shown, when the lead wire 70f connected to the thermal element 80f is wired to the vicinity of the proximal end portion of the third expansion deformable portion 30, it branches from the shaft portion 50 so as to branch from the third expansion deformable portion 30. Are wired toward the heat element 80f side along the outer peripheral surface of the. As shown in FIG. 6B, the lead wires 70a, 70b, 70c, and 70d other than the lead wire 70e and the lead wire 70f are wired toward the distal end side along the outer peripheral surface of the shaft portion 50. The covering material 41 is provided between the covering material 41 and each of the expanded deformable portions 10, 20, 30, between the covering material 41 and the shaft portion 50, and between the tube 40 and the shaft portion 50. It arrange | positions so that the outer peripheral surface of each member may be covered so that the lumen | rumen 47b connected to the formed lumen | rumen 47a may be formed.

As shown in FIG. 7B, when the lead wire 70c connected to the thermal element 80c is wired to the vicinity of the proximal end portion of the second expansion deformable portion 20, the lead wire 70c is branched from the shaft portion 50, 2 Wired along the outer peripheral surface of the extended deformable portion 20 to the heat element 80c side. Although not shown in the drawings, the lead wire 70d connected to the thermal element 80d is branched from the shaft portion 50 so as to be branched from the shaft portion 50 when wired to the vicinity of the proximal end portion of the second expansion deformation portion 20. Are wired toward the heat element 80d side along the outer peripheral surface of the wire. As shown in FIG. 6C, each lead wire 70a, 70b connected to each of the thermal elements 80a, 80b provided in the first expansion deformable portion 10 has a distal end side along the outer peripheral surface of the shaft portion 50. Wired towards

As shown in FIG. 7C, when the lead wire 70a connected to the thermal element 80a is wired to the vicinity of the proximal end portion of the first expansion deformable portion 10, the lead wire 70a is branched from the shaft portion 50, 1 Wired along the outer peripheral surface of the extended deformable portion 10 to the heat element 80a side. Although not shown in the drawings, the lead wire 70b connected to the thermal element 80b is branched from the shaft portion 50 when wired to the vicinity of the proximal end portion of the first expansion deformation portion 10, so that the first expansion deformation portion 10 is branched. Is wired toward the heat element 80b side along the outer peripheral surface of the wire.

As described above, since each of the lead wires 70a to 70f is wired along the respective extended deformation portions 10, 20, and 30, it is possible to easily connect to the respective heat elements 80a to 80f. . In addition, since each lead wire 70a to 70f is covered with a member having electrical insulation, it is possible to more reliably prevent leakage from the lead wires 70a to 70f, and safety in use. Can be further increased. Note that the wiring (routing) of the lead wire 70 is not limited to that shown in FIGS. 5 to 7, and may be, for example, along the inner surface side of each of the expansion deformable portions 10, 20, and 30. Good.

The shaft portion 50 is constituted by a linear member that passes through the lumen 67 of the sheath 60. The shaft portion 50 is preferably made of a material having flexibility in consideration of, for example, introduction into a living body. For example, long elastic wires such as superelastic alloys such as nickel-titanium alloys and copper-zinc alloys, metal materials such as stainless steel, and resin materials with relatively high rigidity, such as polyvinyl chloride, polyethylene, polypropylene, and ethylene. The shaft portion 50 can be formed by coating a resin material such as a propylene copolymer.

Each of the first expansion deformation portion 10, the second expansion deformation portion 20, and the third expansion deformation portion 30 disposed on the distal end side of the shaft portion 50 is shaped in advance so as to expand and contract, and so-called It is configured to be self-expanding. Further, each of the expansion deformable portions 10, 20, 30 divides a plane that intersects the axial direction of the shaft portion 50 (a plane that passes through the axis of the shaft portion 50) around the shaft portion 50 when it is expanded and deformed. It is comprised by the linear member to do. Since each expansion deformation part 10, 20, 30 is comprised by another linear member, it expands and contracts individually. The “linear member” in the present specification means a member having a certain length that can be shaped so as to partition a predetermined plane when expanded and deformed. The shape, outer dimensions, etc. are not particularly limited, and for example, a flat plate shape or a belt shape may be included.

8A shows a state when the second expansion deforming portion 20 contracts, and FIG. 8B shows a state when the second expansion deforming portion 20 expands. Each drawing of FIG. 8 shows the second extended deformation portion 20 when the plane A indicated by a broken line in FIG. The plane A is a plane parallel to the Z-axis direction orthogonal to the axial direction of the shaft portion 50 (a plane viewed from the direction of the arrow 8A).

As shown in FIG. 8A, the second expanded deformable portion 20 is bent into a predetermined shape in a contracted state covered with the sheath 60 or the like to form a flat outer shape. On the other hand, as shown in FIG. 8B, when expanded, a substantially circular plane 21 is formed (expanded deformation is indicated by an arrow e). Similar to the second expansion deforming portion 20, each of the first expansion deforming portion 10 and the third expansion deforming portion 30 defines a substantially circular plane when fully expanded as shown in FIG. To do. Further, in the contracted state covered with the sheath 60 or the like, as shown by an arrow s in FIG. 4B, each is bent into a predetermined shape to form a flat outer shape. Each expansion deformation part 10, 20, 30 is shaped in advance so as to be able to form a circular plane as described above in a state in which no load is applied from the outside.

In order to enable the above-described expansion deformation, each expansion deformation portion 10, 20, 30 can be constituted by a linear member made of, for example, an alloy exhibiting superelasticity in a living body. An alloy exhibiting superelasticity in a living body is a property that at least at a living body temperature (around 37 ° C.), even if it is deformed (bent, pulled, compressed) to a region where normal metal undergoes compositional deformation, it is almost restored to its original shape. And is also referred to as a shape memory alloy, a superelastic alloy, or the like. The shape memory alloy and the superelastic alloy are not particularly limited, but for example, titanium-based (Ti—Ni, Ti—Pd, Ti—Nb—Sn, etc.) and copper-based alloys are preferable. However, it is not limited to alloys that exhibit superelasticity. For example, each expansion can be performed using an alloy having spring properties such as stainless steel (SUS304), β titanium steel, Co—Cr alloy, nickel titanium alloy, etc. It is also possible to configure the deformable portions 10, 20, and 30. In addition, when each expansion deformation part 10, 20, 30 is comprised with a shape memory alloy or a superelastic alloy, when each expansion deformation part 10, 20, 30 is extruded from the sheath 60, each expansion deformation part 10 is shown. , 20, 30 expanding force (repulsive force acting when the shape memory alloy or superelastic alloy is restored to its original shape) is directed toward the blood vessel wall, and the thermal element 80 can be tightly adhered to the blood vessel wall. Therefore, it is preferable that each of the expanded deformable portions 10, 20, and 30 is made of these materials. Thereby, since the thermal element 80 of each expansion deformation part 10,20,30 contacts a blood vessel wall reliably, it can perform efficient thermal cauterization.

As a method of attaching the linear members constituting each of the expanded deformable portions 10, 20, 30 to the shaft portion 50, for example, an excess portion of the linear member is formed at the end of each expanded deformable portion 10, 20, 30. In addition, as shown in FIG. 4A, a method of forming the fixing portion 56 by winding the surplus portion around the shaft portion 50 can be selected. In order to improve the fixing force with respect to the shaft portion 50, it is possible to use soldering, an adhesive material, welding, or the like in combination according to the type of the constituent material. Moreover, as shown to FIG. 4 (A), the front-end | tip part 51 of the shaft part 50 can be functioned as a guide wire by making it the state exposed without winding the linear member around the front-end | tip part 51 of the shaft part 50. FIG. it can. Thereby, since it becomes possible to comprise the ablation catheter 100 as an on-the-wire type catheter device, it becomes possible to further improve the deliverability in the living body.

It is possible to provide an X-ray contrast marker in each of the expansion deformable portions 10, 20, and 30. The X-ray contrast marker is, for example, an arbitrary position such as a place showing the position of the thermal element 80, a place showing the position in the axial direction of each of the expanded deformable portions 10, 20, 30 and a place showing the tip portion 51 of the shaft portion 50. Can be formed. The X-ray contrast marker can be formed using, for example, a metal such as platinum, gold, silver, titanium, tungsten, or an X-ray opaque material such as an alloy thereof.

11 (A) to 11 (C) show the positional relationship between the expanded deformable portions 10, 20, and 30 when the shaft portion 50 is viewed from the front end portion 51 side.

The angle difference θ21 between the first expansion deformation part 10 and the second expansion deformation part 20 is set to 60 °, and the angle difference θ22 between the first expansion deformation part 10 and the third expansion deformation part 30 is set. Is also set to 60 °. Thereby, each expansion deformation | transformation part 10,20,30 makes an angle difference of 60 degrees mutually equally along the circumferential direction (direction shown by the arrow b in FIG. 11 (A)) around the axis of the shaft part 50. It is provided and arranged. That is, since the planes formed when the respective extended deformable portions 10, 20, and 30 are expanded intersect with each other at an angle of 60 °, the planes formed by each do not overlap on the same plane.

11A, the heat element 80a and the heat element 80b arranged in the first expansion deformable portion 10 are arranged at different positions in the circumferential direction around the axis of the shaft portion 50. Specifically, an angular difference of 180 ° is provided in the circumferential direction so that the thermal element 80a and the thermal element 80b are arranged at opposing positions. Therefore, when the first dilation deformable portion 10 is expanded in the renal artery RA, the thermal element 80a and the thermal element 80b are arranged on the same orthogonal cross section of the inner wall W of the renal artery RA, but the inner wall In the circumferential direction of W, the positions are shifted. Similarly, as shown in FIG. 11B, an angular difference of 180 ° is formed between the thermal element 80c and the thermal element 80d arranged in the second expansion deformable portion 20 in the circumferential direction around the axis of the shaft portion 50. Provided (similar to the angle difference θ1 shown in FIG. 8B). Similarly, as shown in FIG. 11C, an angle of 180 ° between the thermal element 80e and the thermal element 80f arranged in the third expansion deformable portion 30 in the circumferential direction around the axis of the shaft portion 50. Make a difference.

As described above, in the ablation catheter 100, the expansion deforming portions 10, 20, and 30 are disposed at different positions in the axial direction of the shaft portion 50, so that each heat disposed in the first expansion deforming portion 10 is used. The elements 80a and 80b, the thermal elements 80c and 80d arranged in the second expansion deformation part 20, and the thermal elements 80e and 80f arranged in the third expansion deformation part 30 are respectively in different positions in the axial direction. Be placed. Furthermore, each expansion deformation part 10, 20, 30 expands in a different direction intersecting with the axial direction (axial core) of the shaft part 50, so that each thermal element 80 a disposed in the first expansion deformation part 10, 80b, the thermal elements 80c and 80d arranged in the second expansion deformation part 20, and the thermal elements 80e and 80f arranged in the third expansion deformation part 30 are at different positions in the circumferential direction of the shaft part 50. Be placed. That is, the thermal elements 80a to 80e are arranged at different positions (positions that do not overlap) with respect to the shaft portion 50 in both the axial direction and the circumferential direction. In addition, it is preferable to provide the space | interval of 5 mm or more in the axial direction between each thermal element 80, for example. This is because by providing an interval of 5 mm or more, it becomes possible to more reliably prevent the narrowed portion from being formed when ablation is performed.

Next, an example of use of the ablation catheter 100 according to the present embodiment will be described with reference to FIGS.

First, the ablation catheter 100 and the energy supply device 110 are connected via the electric cable 111. Then, the counter electrode plate 120 is attached to the body surface of the patient.

Next, the ablation catheter 100 is introduced into the living body. The ablation catheter 100 can be introduced into the living body by a well-known method. For example, a predetermined sheath (not shown) is attached to the radial artery or the brachial artery. Next, a guide wire (not shown) is introduced to the vicinity of the renal artery RA through the sheath. Thereafter, as shown in FIG. 9A, the guiding catheter 131 is inserted, and the distal end opening 131a of the guiding catheter 131 is placed in the renal artery RA. The guide wire is appropriately removed from the guiding catheter 131. Note that the guide wire and guiding catheter 131 may be introduced from a blood vessel such as a femoral artery or an axillary artery.

Next, as shown in FIG. 9B, the ablation catheter 100 is inserted through the guiding catheter 131, and the distal end portion of the ablation catheter 100 is introduced into the renal artery RA. At this time, each of the expanded deformable portions 10, 20, 30 is stored in the sheath 60 in a contracted state. When the ablation catheter 100 is introduced, the guide wire 130 is inserted through the guide wire lumen 66 of the sheath 60, whereby the introduction operation can be performed smoothly. After the introduction of the ablation catheter 100, the guiding catheter 131 may be removed as appropriate, or may be introduced into the living body until the procedure is completed.

When the distal end of the ablation catheter 100 reaches the renal artery RA, the distal end of the ablation catheter 100 is protruded from the guiding catheter 131. Then, as shown in FIG. 10A, the sheath 60 is retracted as indicated by an arrow a <b> 2, and the expansion deformable portions 10, 20, 30 are protruded from the sheath 60. Each expansion deformation part 10, 20, 30 projects from the sheath 60 and simultaneously starts expansion deformation. As shown in FIG. 10 (B), each of the expanded deformable portions 10, 20, and 30 is expanded and deformed in a state where the expanded deformable portions 10, 20, and 30 are arranged at different positions in the extending direction X ′ of the renal artery RA. Press against the inner wall W of the renal artery RA. Under X-ray imaging, the position where the thermal element 80 is disposed is determined in advance, and the expansion deformable portions 10, 20, and 30 are protruded from the sheath 60, and at the same time, the thermal element 80 is treated as a renal sympathetic nerve. You may make it locate and arrange | position in the position close | similar to RN.

As shown in FIG. 11 (A), each of the thermal elements 80a and 80b arranged in the first dilation deformable portion 10 is caused by the pressing force acting in the direction in which the first dilation deformable portion 10 expands, thereby causing the renal artery RA. Is firmly held in a state of being positioned with respect to the inner wall W. Further, as shown in FIG. 11 (B), each of the thermal elements 80c and 80d arranged in the second expansion deforming portion 20 is caused by the pressing force acting in the direction in which the second expansion deforming portion 20 expands. It is firmly held in a state of being positioned with respect to the inner wall W of the artery RA. Further, as shown in FIG. 11C, each of the thermal elements 80e and 80f arranged in the third expansion / deformation portion 30 is caused by the pressing force acting in the direction in which the third expansion / deformation portion 30 expands. It is firmly held in a state of being positioned with respect to the inner wall W of the artery RA.

Next, high-frequency electrical energy is supplied from the energy supply device 110 to the thermal element 80 to heat the living tissue (inner wall W) located in the vicinity of the thermal element 80, and renal sympathy located on the outer peripheral surface of the renal artery R. Ablate nerve RN. By causing renal sympathetic nerve RN to undergo necrosis, thermal alteration, exfoliation, and the like, the sympathetic nervous system can be suppressed, and the effect of lowering blood pressure in patients with treatment-resistant hypertension can be obtained. Since a total of six thermal elements 80 arranged in each of the expanded deformable portions 10, 20, and 30 can be ablated at the same time, the treatment time can be shortened. At this time, high-frequency electric energy may be selectively and sequentially supplied to each of the six thermal elements 80 to perform ablation six times for each location. Since each of the thermal elements 80 is arranged at an appropriate interval in the extending direction X ′ of the renal artery RA and the circumferential direction of the inner wall W, a stenosis is formed in the renal artery RA with ablation. Can be prevented.

When the treatment is continuously performed on other parts, the sheath 60 is operated to temporarily accommodate each of the expanded deformable portions 10, 20, 30 in the sheath 60. After the expansion deforming portions 10, 20, and 30 are moved again to predetermined positions, the expansion deforming portions 10, 20, and 30 are protruded from the sheath 60 to be expanded and deformed. Thereafter, the same procedure is repeated to advance the procedure. After completing the treatment for one of the right and left renal arteries RA, the other renal artery RA may be continuously treated. After all procedures are completed, the ablation catheter 100 is removed.

As described above, according to the ablation catheter 100 according to the present embodiment, the plurality of expansion deformable portions 10, 20, and 30 in which at least two or more thermal elements 80 are disposed are disposed at different positions in the axial direction of the shaft portion 50. In addition, since each of the expansion deformable portions 10, 20, and 30 is configured to be expandable and deformable in different directions intersecting the axial direction of the shaft portion 50, each of the expansion deformable portions 10, 20, and 30 is configured. When expanded and deformed in the renal artery RA, the thermal elements 80a to 80f can be arranged at a treatment target site with an appropriate interval. Furthermore, each expansion deformation part 10, 20, 30 is individually expanded and deformed, and the thermal element 80 is held in a state of being positioned with respect to the treatment target site, so that the thermal element 80 is displaced during treatment. Can be suitably prevented. Thus, treatment can be performed on a plurality of treatment target parts at the same time, and inadvertent displacement of the thermal element 80 can be prevented, so that the treatment time can be shortened and the efficiency can be reduced. It is possible to suitably prevent the formation of a stenosis part during treatment while aiming at a general thermal ablation.

Further, since at least one thermal element 80 is provided in each of the plurality of expansion deformable portions 10, 20, 30, each heat element 80 provided in each of the expansion deformable portions 10, 20, 30 is used. Thus, ablation can be performed, and the procedure can be performed more efficiently.

In addition, a linear member that is shaped in advance so as to divide a plane intersecting the axial direction of the shaft portion 50 around the shaft portion 50 when each of the expansion deformable portions 10, 20, 30 is expanded and deformed. Therefore, it is possible to apply a pressing force along the surface direction in which the plane defined by each of the expansion deformable portions 10, 20, and 30 is widened, and the expansion deformable portions 10, 20, and 30 are arranged on each of the expansion deformable portions 10, 20, and 30. It is possible to stably hold the thermal element 80 against the treatment target site. Thereby, it can prevent more reliably that position shift generate | occur | produces in a thermal element.

Further, since the first to third expansion / deformation parts 10, 20, and 30 divide planes intersecting each other at an angle of 60 ° in the circumferential direction of the shaft part 50, the first to third expansion / deformation parts 10 are provided. , 20, and 30, each of the thermal elements 80 can be arranged with respect to the treatment target site at appropriate intervals in the axial direction and the circumferential direction of the shaft portion 50, so that the stenosis accompanying the treatment It becomes possible to further reduce the risk of forming the part.

Further, since a plurality of thermal elements 80 are arranged at different positions in the circumferential direction of the shaft portion 50 for each of the expansion deformable portions 10, 20, and 30, the same orthogonality of the renal artery RA including the treatment target site A plurality of thermal elements 80 can be arranged at appropriate intervals with respect to the inner peripheral surface located on the cross section, so that the treatment time can be further shortened and the narrowing accompanying the treatment. It becomes possible to reduce the risk of forming the part.

Further, if each of the plurality of thermal elements 80a to 80f disposed in the plurality of expansion deformable portions 10, 20, and 30 is disposed at a different position in the circumferential direction of the shaft portion 50, the treatment target region is included. While securing an appropriate interval in the extending direction of the renal artery RA, ensuring an appropriate interval on the inner peripheral surface located on the same orthogonal cross section of the renal artery RA, the thermal elements 80a to 80f are placed on the treatment target site. Therefore, it is possible to greatly reduce the risk of forming a stenosis portion associated with the treatment.

In addition, if each of the plurality of thermal elements 80a to 80f is arranged at an equal interval in the circumferential direction of the shaft portion 50, the inner peripheral surface located on the same orthogonal cross section of the renal artery RA. Since it is possible to arrange the thermal elements 80a to 80f at equal intervals, it is possible to further reduce the risk of forming a constriction portion due to the treatment.

In addition, a sheath 60 into which a plurality of expansion deformable portions 10, 20, 30 can be inserted, and insertion of each expansion deformable portion 10, 20, 30 into the sheath 60 by moving the sheath 60 in the axial direction and the sheath 60. And a hand operating part 90 provided with an operating member 91 for operating the protrusions of the expansion deforming parts 10, 20, 30 from the tip opening 61 a of the plurality of expansion deforming parts 10, 20, When each of 30 is contracted and deformed as it is inserted into the sheath 60 and expanded and deformed as it protrudes from the distal end opening 61a of the sheath 60, a plurality of expanded deformable portions 10, 20, Until the 30 is delivered, each of the expansion deformable portions 10, 20, 30 can be contracted and held in the sheath 60, and when placing the thermal element 80 on the treatment target site, From sheath 60 It becomes possible to extend deformed by simple operation of projecting the extended deformation portion 10, 20, 30, it is possible to configure the ablation catheter 100 as user-friendly device.

Next, a modification of the ablation catheter 100 according to the first embodiment described above will be described. In the description of each modification, the same member numbers are assigned to components that can be configured in the same manner as the members already described, and the description thereof is omitted. In addition, configurations that are not particularly mentioned (for example, wiring of lead wires) can be configured in the same manner as the respective parts of the ablation catheter 100 according to the above-described embodiment.

<First Modification>
12 and 13 show an ablation catheter 200 according to a first modification. The ablation catheter 200 is configured as a so-called rapid exchange type catheter device. In this respect, it is different from the ablation catheter 100 described above which is configured as an overwire type catheter device.

As shown in FIG. 12, the distal end portion 61 of the sheath 60 is partially formed with a large outer diameter. As shown in FIG. 13B, a guide wire lumen 66 is formed at the distal end portion 61 of the sheath 60. As shown in FIGS. 12 and 13A, the guide wire lumen 66 is not formed in a portion other than the distal end portion 61 of the sheath 60.

Even when the ablation catheter 200 is configured as such a rapid exchange type catheter, the effects of shortening the treatment time and preventing the formation of a stenosis are not impaired. Further, by configuring as a rapid exchange type catheter, it becomes possible to improve the operability in the living body.

<Second Modification>
14 (A) and 14 (B) show an ablation catheter 300 according to a second modification. The ablation catheter 300 has a shape when the first expansion deforming portion 310, the second expansion deforming portion 320, and the third expansion deforming portion 330 are expanded, and the respective expansion deforming portions 10, 20, and 30 of the ablation catheter 100 described above. Is different.

Fig. 14 (B) is a diagram showing the second expansion deforming portion 320 when the plane A indicated by a broken line in Fig. 14 (A) is viewed from the direction of the arrow 14B. In addition, since the shape of each expansion deformation part 310,320,330 is formed substantially the same, the 2nd expansion deformation part 320 is demonstrated and description of the other expansion deformation parts 310,330 is abbreviate | omitted.

The second expanded deformable portion 320 includes a distal end portion 321 curved toward the distal end side, a proximal end portion 322 curved toward the proximal end side, and a pair of flat portions 323a and 323b extending between the distal end portion 321 and the proximal end portion 322. Are formed in a long and thin ring shape. Compared to the expansion deformed portions 10, 20, 30 etc. formed in a circle, it has a shape extending in the axial direction of the shaft portion 50, so the resistance generated when pushing and pulling the sheath 60 etc. is compared. Can be kept small. For this reason, it is possible to smoothly perform the operation of accommodating the second expansion / deformation section 320 in the sheath 60 and the operation of projecting the second expansion / deformation section 320 out of the sheath 60.

Further, since it is possible to arrange the thermal elements 80c and 80d on the flat portions 323a and 323b extending in the axial direction, the positions of the thermal elements 80c and 80d are relatively set within the range of the length of the flat portions 323a and 323b. It can be freely changed, and it becomes possible to cope with various product specifications. In particular, it is possible to easily cope with the case where it is desired to increase the distance between the thermal elements 80c and 80d.

Each thermal element 80c, 80d can be disposed on a diagonal line d connecting the front end side of the flat portion 323a and the rear end side of the flat portion 323b, for example. By arranging in this way, the distance between the two can be maximized. Therefore, it becomes possible to further reduce the risk that a narrowed portion is formed by ablation.

<Third Modification>
FIGS. 15A and 15B show an ablation catheter 400 according to a third modification. This ablation catheter 400 has a shape when the first expansion deforming portion 410, the second expansion deforming portion 420, and the third expansion deforming portion 430 are expanded, and the respective expansion deforming portions 10, 20, 30 of the ablation catheter 100 described above. Is different.

FIG. 15B is a diagram showing the second expansion deforming portion 420 when the plane A indicated by the broken line in FIG. 15A is viewed in a plan view from the direction of the arrow 15B. In addition, since the shape of each expansion deformation part 410,420,430 is formed substantially the same, the 2nd expansion deformation part 420 is demonstrated and description of the other expansion deformation part 410,430 is abbreviate | omitted.

The taper part 450 which becomes a taper shape toward each edge part is formed in the front-end | tip part and base end part of the 2nd expansion deformation part 420. As shown in FIG. By providing such a tapered portion 450, it is possible to keep the sliding resistance generated when pushing and pulling the sheath 60 and the like relatively small. For this reason, it is possible to smoothly perform the operation of accommodating the second expansion / deformation part 420 in the sheath 60 and the operation of projecting the second expansion / deformation part 420 outside the sheath 60.

<Fourth Modification>
FIG. 16A shows an ablation catheter 500 according to a fourth modification. The ablation catheter 500 has the ablation described above in that each of the first expansion deforming portion 510, the second expansion deforming portion 520, and the third expansion deforming portion 530 is disposed so as to partially overlap in the axial direction. It is different from each expansion deformation part 10, 20, 30 of the catheter 100.

The base end portion of the first expansion deforming portion 510 is disposed so as to intersect the distal end portion of the second expansion deformation portion 520, and the base end portion of the second expansion deformation portion 520 is the third expansion deformation portion 530. It is arranged so as to intersect the tip. With this arrangement, the rotation operation of the proximal end portion of the first expansion deforming portion 510 is regulated within a predetermined range by the distal end portion of the second expansion deforming portion 520, and the proximal end portion of the second expansion deforming portion 520 is restricted. The rotational operation is restricted within a predetermined range by the distal end portion of the third expansion deformation portion 530. Since it is possible to prevent an unnecessary rotational operation from occurring when the expansion deforming portions 510, 520, and 530 are moved in and out of the sheath 60, the operation of accommodating the expansion deforming portions 510, 520, and 530 and the protrusion are performed. The operation can be performed smoothly. Further, even in the case where it is unavoidable to use expansion deforming portions having a certain external dimension or more, by disposing the expansion deforming portions 510, 520, and 530 as shown in the drawing, the thermal elements 80a to 80a are arranged. It becomes possible to adjust the length of the interval between 80f relatively freely.

FIG. 16B shows an ablation catheter 500 'according to another modification. As shown in this modification, the first expansion deformation portion 510, the second expansion deformation portion 520, and the third expansion deformation portion 530 are fixed to the shaft portion 50 at one location of each expansion deformation portion 510, 520, 530. May be. Specifically, the first expansion deforming portion 510 is fixed to the shaft portion 50 at one location on the proximal end side (hand side), and can slide on the shaft portion 50 at one location on the distal end side. Is arranged. For example, the first expanded deformable portion 510 has a hollow ring member 550 in a part thereof, and is slidable with respect to the shaft portion 50. And the 2nd expansion deformation part 520 and the 3rd expansion deformation part 530 are being fixed to the shaft part 50 by one place of the base end side (hand side), and the front-end | tip part is not being fixed with respect to the shaft part 50. . With such a configuration, the first expansion deforming portion 510, the second expansion deforming portion 520, and the third expansion deforming portion 530 are fixed to the shaft portion 50 only at one place, and thus the sheath 60 When projecting from the distal end opening 61a of the sheath 60 or when being housed in the distal end opening 61a of the sheath 60, each of the expansion deforming portions 510, 520, and 530 can be easily expanded and contracted. In addition, the first expansion deformation portion 510, the second expansion deformation portion 520, and the third expansion deformation portion 530 are fixed to the shaft portion 50 at the base end side of each expansion deformation portion 510, 520, 530. It can be easily stored in the tip opening 61a. Note that the portions of the expansion deforming portions 510, 520, and 530 that are fixed to the shaft portion 50 are shafts when the expansion deforming portions 510, 520, and 530 are removed from the distal end opening 61a of the sheath 60 and expanded and deformed. It is preferable to fix the shaft 50 with a certain fixing force so as not to rotate inadvertently in the circumferential direction of the portion 50.

FIG. 16C shows an ablation catheter 100 'according to still another modification. In the ablation catheter 100 shown in FIG. 4 and FIG. 5, the first expansion deformable portion 10, the second expansion deformable portion 20, and the third expansion deformable portion 30 are two portions of the expansion deformable portions 10, 20, and 30. Although it is fixed to 50, it is not limited to this. Similarly to the modification shown in FIG. 16B, for example, the first expansion deformation unit 10, the second expansion deformation unit 20, and the third expansion deformation unit 30 are provided at one place of each expansion deformation unit 10, 20, 30. It may be fixed to the shaft portion 50. Specifically, the first expansion deformable portion 10 is fixed to the shaft portion 50 at one location on the proximal end side (hand side), and can slide on the shaft portion 50 at one location on the distal end side. Is arranged. For example, the first expansion deformable portion 10 has a hollow ring member 150 in a part thereof and is slidable with respect to the shaft portion 50. And the 2nd expansion deformation part 20 and the 3rd expansion deformation part 30 are being fixed to the shaft part 50 by one place of the base end side (hand side). With such a configuration, the first expansion deformable portion 10, the second expansion deformable portion 20, and the third expansion deformable portion 30 are fixed to the shaft portion 50 at only one location, and thus the sheath 60 When projecting from the distal end opening 61a of the sheath 60 or when being housed in the distal end opening 61a of the sheath 60, each of the expansion deformable portions 10, 20, and 30 can be easily expanded and contracted. Moreover, since the base end side of each expansion deformation part 10, 20, 30 is being fixed to the shaft part 50, the 1st expansion deformation part 10, the 2nd expansion deformation part 20, and the 3rd expansion deformation part 30 are the sheath 60's. It can be easily stored in the tip opening 61a. In addition, the site | part fixed to the shaft part 50 in each expansion deformation part 10,20,30 is a shaft when extracting each expansion deformation part 10,20,30 from the front-end | tip opening part 61a of the sheath 60, and carrying out expansion deformation. It is preferable to fix the shaft 50 with a certain fixing force so as not to rotate inadvertently in the circumferential direction of the portion 50.

<Fifth Modification>
FIG. 17 shows an ablation catheter 600 according to a fifth modification. The ablation catheter 600 is configured such that each of the first expanded deformable portion 610 and the second expanded deformable portion 620 is movable along the axial direction of the shaft portion 50, and each of the expanded deformable portions 610, 620 It differs from the ablation catheter 100 described above in that stoppers 652a and 652b for limiting the amount of movement are provided.

The ablation catheter 600 includes two expansion deformation portions, a first expansion deformation portion 610 and a second expansion deformation portion 620. The expansion deforming portions 610 and 620 are arranged so that planes formed when the expansion deformation is performed are orthogonal to each other.

The ablation catheter 600 is provided with a plurality of ring members 651a and 651b. The first ring member 651a is configured integrally with the distal end portion of the first expansion deformation portion 610. The second ring member 651 b is configured integrally with the proximal end portion of the first expansion deforming portion 610 and the distal end portion of the second expansion deforming portion 620.

The shaft portion 50 is inserted through the ring members 651a and 651b. Each of the ring members 651 a and 651 b is movable along the axial direction of the shaft portion 50 while being supported by the shaft portion 50. Similarly, the first expansion deformation portion 610 and the second expansion deformation portion 620 that are integrally formed with the ring members 651 a and 651 b are movable along the axial direction of the shaft portion 50. As will be described later, the base end portion of the second expansion deformable portion 620 is configured integrally with a hollow member 645 disposed in a predetermined tube 640, and along the axial direction together with the tube 640 and the hollow member 645. Can be moved.

As shown in FIG. 17B, when the sheath 60 is moved to the proximal end side from the state in which the expansion deforming portions 610 and 620 are accommodated in the sheath 60, the expansion deforming portions 610 and 620 are moved together with the sheath 60. Although it moves backward by a certain distance, when each ring member 651a, 651b hits each stopper 652a, 652b, the subsequent movement is restricted. While the movement of each expansion deformation part 610 and 620 is restricted by the stoppers 652a and 652b, the sheath 60 moves backward. By moving only the sheath 60 backward, each of the expanded deformable portions 610 and 620 can be reliably projected from the sheath 60.

Further, as shown in FIG. 17C, when the sheath 60 is moved to the distal end side in order to accommodate the expansion deforming portions 610 and 620 in the sheath 60, the movement of the expansion deforming portions 610 and 620 is performed. Since it is limited by the stoppers 652a and 652b, the expansion deformable portions 610 and 620 can be easily pushed into the sheath 60 by advancing the sheath 60.

In this way, each expansion deforming portion 610, 620 can be moved, and further, the sheath 60 can be operated by pushing and pulling alone while restricting the movement of each expansion deforming portion 610, 620 by each stopper 652a, 652b. The pushing and pulling force can be transmitted from the sheath 60 to each of the expansion deforming portions 610 and 620 to assist the expansion and contraction deformation of each of the expansion deforming portions 610 and 620. For this reason, each expansion deformation part 610, 620 can be smoothly moved into and out of the sheath 60. In the ablation catheter 600 according to the present modification, the push / pull force from the sheath 60 or the like is not transmitted in a state in which each of the expansion deformable portions 610 and 620 is temporarily deformed and pressed against the inner wall W. Nevertheless, the amount of expansion deformation of each expansion deformation portion 610, 620 so that the expansion deformation portions 610, 620 do not inadvertently move (in other words, a pressing force that acts on the living tissue when the expansion deformation occurs) ) Can be adjusted accordingly.

Next, the wiring of the lead wire 70 in the ablation catheter 600 according to this modification will be described with reference to FIGS. FIG. 18 is an enlarged perspective view showing the distal end portion of the ablation catheter 600, and FIG. 19 shows cross sections of the respective portions of the ablation catheter 600. (A) in FIG. 19 shows a cross section taken along line 19A-19A shown in FIG. 18, (B1) to (B3) in FIG. 19 show cross sections taken along line 19B-19B shown in FIG. (C1) to (C3) in FIG. 19 are cross sections taken along the line 19C-19C shown in FIG. 18, and (D1) to (D3) in FIG. 19 are taken along the line 19D-19D shown in FIG. A cross section is shown, and (E1) to (E3) in FIG. 19 are cross sections taken along line 19E-19E shown in FIG. An alternate long and short dash line C <b> 1 illustrated in FIG. 19 indicates a central axis passing through the axis of the shaft portion 50.

As shown in FIGS. 18 and 19A, a tube 640 that covers the shaft 50, the predetermined hollow member 645, and the lead wire 70 is disposed on the proximal end side of the second expansion deformable portion 620. As the tube 640, for example, a tube made of a resin material having heat shrinkability and electrical insulation can be used as in the tube 40 described above.

The shaft portion 50 is disposed in a lumen 647b included in the hollow member 645. The lead wire 70 is disposed in a lumen 647 a formed between the hollow member 645 and the tube 640. The hollow member 645 is configured integrally with the second expansion / deformation part 620 and forms a base (shaft part) of the second expansion / deformation part 620. The base end portion of the linear member constituting the second expanded deformable portion 620 is bifurcated so as to form a circular shape from the outer surface of the hollow member 645, and as shown in FIG. Extends through the position. The hollow member 645 can be made of the same material as that of the second expanded deformable portion 620, and can be made of, for example, a shape memory alloy or a superelastic alloy.

As shown in FIGS. 18 and 19A, each of the lead wires 70 is wired along the outer peripheral surface of the hollow member 645 up to the base end portion of the second expansion deformable portion 620.

As shown in FIGS. 19B1 to 19B3, the lead wire 70a connected to the thermal element 80a arranged in the first expansion deforming portion 610 and the heat element 80c arranged in the second expansion deforming portion 620 are connected. When the lead wire 70c is wired to the vicinity of the proximal end portion of the second expansion deformable portion 620, the lead wire 70c is wired along one side in the outer peripheral direction of the second expansion deformable portion 620 (the back side of the paper surface in FIG. 18). Is done. On the other hand, the lead wire 70b connected to the thermal element 80b arranged in the first expansion deforming portion 610 and the lead wire 70d connected to the heat element 80d arranged in the second expansion deforming portion 620 are the second expansion deforming portion. When wiring is performed up to the vicinity of the base end portion of 620, wiring is performed along the other side in the outer peripheral direction of the second expansion deformable portion 620 (the front side of the paper surface in FIG. 18).

The portion where the lead wire 70 is wired in the first expansion deformation portion 610 and the portion where the lead wire 70 is wired in the second expansion deformation portion 620 are covered with a covering material 641. The covering material 641 is each expanded and deformed so as to form a lumen 647c communicating with the lumen 647a formed between the hollow member 645 and the tube 640 between the covering material 641 and the expanded deformable portions 610 and 620. It arrange | positions so that the outer peripheral surface of the parts 610 and 620 may be covered. The lead wire 70 passes through the lumen 647c and is wired toward each thermal element 80. As the covering material 641, for example, a material made of a resin material having heat shrinkability and electrical insulation similar to the covering material 41 described above can be used.

As shown in FIG. 18, when the lead wire 70 c connected to the thermal element 80 c arranged in the second expansion deformable portion 620 is wired to the vicinity of the thermal element 80 c, the lead wire 70 c is led out from the covering material 641, and the distal end portion is Connected to the thermal element 80c. Similarly, when the lead wire 70d connected to the thermal element 80d arranged in the second expansion deformable portion 620 is wired up to the vicinity of the thermal element 80d, the lead wire 70d is led out from the covering material 641, and the leading end is the thermal element 80d. Connected to.

As shown in FIGS. 19C1 to 19C3, the lead wires 70a and 70b connected to the thermal elements 80a and 80b of the first expansion deformable portion 610 are provided on the distal end side of the second expansion deformable portion 620, respectively. Are wired along the outer peripheral surface of the second extended deformation portion 620.

As shown in FIGS. 18 and 19 (D1) to (D3), when the lead wire 70a is wired up to the base end portion of the first expanded deformable portion 610, one side of the first expanded deformable portion 610 in the outer circumferential direction. Wiring is performed along (upper side of the paper surface in FIG. 18). On the other hand, when the lead wire 70b is wired to the base end portion of the first expansion deforming portion 610, the lead wire 70b is wired along the other side in the outer peripheral direction of the first expansion deforming portion 610 (the lower side of the drawing in FIG. 18). The The portion of the ring member 651b where the lead wires 70a and 70b are wired is covered with a covering material 641.

As shown in FIG. 18, when the lead wire 70a connected to the thermal element 80a disposed in the first expansion deformable portion 610 is wired to the vicinity of the thermal element 80a, the lead wire 70a is led out from the covering material 641, and the tip portion is Connected to the thermal element 80a. Similarly, when the lead wire 70b connected to the thermal element 80b arranged in the first expansion deformed portion 610 is wired up to the vicinity of the thermal element 80b, the lead wire 70b is led out from the covering material 641, and the tip portion is the thermal element 80b. Connected to.

As shown in FIGS. 19 (E1) to (E3), the lead wire 70 is not wired on the distal end side of the first expanded deformable portion 610. For this reason, the coating material 641 is not covered at the tip of the first expansion deformable portion 610.

Thus, since each of the lead wires 70a to 70d is wired along the respective extended deformation portions 610 and 620, it is possible to easily connect to each of the thermal elements 80a to 80d. In addition, since the lead wires 70a to 70d are covered with a member having electrical insulation, it is possible to more reliably prevent leakage from the lead wires 70a to 70d, and safety during use. Can be further increased. Note that the wiring (handling) of the lead wire 70 is not limited to that shown in FIGS. 18 and 19, and for example, the inner surfaces of the respective extended deformation portions 610 and 620 may be provided.

The shape and the number of stoppers exemplified in the present modification are not particularly limited, and can be changed as long as the movement of the extended deformation portion can be limited. In addition, since the expansion deformable portion can exhibit the effect of being movable as long as at least one of the plurality is movable, the number of expansion deformable portions configured to be movable can be changed. is there.

The ablation catheter according to the first embodiment described above and the modifications thereof can be combined as appropriate. Further, the number of expansion deformation portions, the shape of a plane formed when the expansion deformation is performed, the number and arrangement of thermal elements disposed in the expansion deformation portion are not limited to the examples described in the embodiment, and are appropriately It is possible to change. For example, a configuration in which one or more thermal elements are provided in each of the expansion deformable portions provided in the ablation catheter is shown. However, the number of thermal elements installed may be at least two or more for one ablation catheter. What is necessary is just to add the expansion deformation part in which the thermal element is not provided. In addition, for example, the shape of the plane formed when the expansion deforming portion is expanded and deformed is not limited to a circle or the illustrated shapes, and may be formed in a rectangular shape, an ellipse shape, or other geometric shapes. The planar shape may be different for each expansion deformation part. Further, for example, when the expansion deforming portion is not a point-symmetric shape such as a circle, the thermal element can be arranged at a portion that expands and deforms outward most when the expansion deforming portion expands and deforms. By arranging in this way, it is possible to more reliably prevent the thermal element from being displaced when performing ablation.

Second Embodiment
Next, an ablation catheter 700 according to the second embodiment of the present invention will be described. In the description of the ablation catheter 100 described above, components that can be configured in the same manner as the members already described are denoted by the same member numbers and description thereof is omitted. In addition, configurations that are not particularly mentioned can be configured in the same manner as each part of the ablation catheter 100 according to the above-described embodiment.

As shown in FIGS. 20 to 22, the ablation catheter 700 according to the present embodiment has expansion deformable portions 710 and 720 formed on a predetermined tubular member 750 constituting the shaft portion. In such a point, it is different from the ablation catheter 100 described above including the expanded deformable portions 10, 20, and 30 configured by linear members.

As shown in FIG. 22A, the tubular member 750 has slits 712 and 722 formed at different positions in the axial direction of the tubular member 750. The tubular member 750 can be made of, for example, an alloy or the like that exhibits superelasticity in a living body, like the linear member that forms each of the expanded deformable portions 10, 20, and 30 of the ablation catheter 100 described above. In this embodiment, the tubular member 750 is constituted by a hollow member made of nickel titanium alloy.

The portion where the slit 712 is not formed, that is, the portion where the tube wall of the tubular member 750 is left is located at a position shifted in the circumferential direction from the portion where the slit 712 is formed. The easy portions 711a and 711b are configured. Similarly, the portion where the tube wall of the tubular member 750 that is present in the position shifted in the circumferential direction from the portion where the slit 722 is formed constitutes the easily deformable portions 721a and 721b that form the second expansion deformable portion 720. .

The slit 712 penetrates the tubular member 750 in the width direction (Y-axis direction), and the slit 722 penetrates the tubular member 750 in the height direction (Z-axis direction). That is, the slit 712 and the slit 722 are formed at positions shifted by 90 ° in the circumferential direction.

The slits 712 and 722 are not limited to the shape shown in FIG. 22A, and may be provided so as to intersect the axial direction of the tubular member 750. For example, the slits 712 and 722 are not limited to a rectangle in front view, and may be a parallelogram or the like. By deforming the shape of the slits 712 and 722, the shape and length of each of the easily deformable portions 711a, 711b, 721a, and 721b can be adjusted.

The easily deformable portions 711a and 711b forming the first expansion deformable portion 710 are formed in pairs so as to face each other. Each of the easily deformable portions 711a and 711b is shaped in advance so as to form an expanded shape shown in FIG. 22B in a natural state (a state where no external force is applied). Each of the easy-to-deform portions 711a and 711b is expanded and deformed into a gentle mountain shape in which the central portion expands most. Further, each of the easily deformable portions 711a and 711b is expanded and deformed into a symmetrical shape in the Z-axis direction. Each of the easily deformable portions 711a and 711b contracts to form a substantially linear shape as shown in FIG. 22A while being accommodated in the sheath 60.

The easily deformable portions 721a and 721b forming the second expansion deformable portion 720 are formed substantially the same as the easily deformable portions 711a and 711b forming the first expandable deformable portion 710, and are self-expanding into the shape shown in FIG. Is configured to do. Each of the easily deformable portions 721a and 721b contracts to form a substantially linear shape as shown in FIG. 22A while being accommodated in the sheath 60.

The distal end portion 751 and the intermediate portion 755 of the tubular member 750 are not restrained with respect to the predetermined inner tube 740. Therefore, when each of the easily deformable portions 711a, 711b, 721a, 721b is expanded and deformed, the distal end portion 751 of the tubular member 750 moves toward the proximal end along the outer surface of the inner tube 740, and the axial length is increased. Appears to be shorter.

23A, when the easily deformable portions 711a and 711b are expanded in the renal artery RA, the thermal elements 80a and 80b disposed in the easily deformable portions 711a and 711b are pressed against the inner wall W. As a result, it is possible to perform ablation while preventing the thermal elements 80a and 80b from being displaced. Since each of the easily deformable portions 711a and 711b has a flat plate-like cross-sectional shape, the heat elements 80a and 80b can be firmly pressed against the inner wall W by the surface, and it is more sure that the displacement occurs. Can be prevented. As shown in FIG. 23B, the easily deformable portions 721a and 721b similarly hold the thermal elements 80c and 80d against the inner wall W of the renal artery RA.

As shown in FIG. 22A, an inner tube 740 is inserted through the tubular member 750. In FIGS. 22A and 22B, in order to clearly show the positional relationship between the tubular member 750 and the inner tube 740, the inner tube 740 is illustrated by a two-dot chain line (virtual line). As shown in FIG. 21, a guide wire lumen 747 through which the guide wire 130 is inserted is formed in the inner tube 740.

As shown in FIG. 22 (A), the distal end portion 741 of the inner tube 740 is formed with a distal end opening portion 741a for allowing the guide wire 130 to protrude.

Since each of the expanded deformation portions 710 and 720 is constituted by a part of the tube wall of the tubular member 750, the inner tube 740 can be inserted into the lumen 757 of the tubular member 750. The lumen of the inner tube 740 is used as a guide wire lumen 747. Therefore, it is not necessary to separately provide a guide wire lumen 747 in the sheath 60. Therefore, in the ablation catheter 700, the diameter of the sheath 60 can be reduced as compared with the ablation catheter 100 according to the above-described embodiment.

The heat element 80a is arranged on the outer surface of the portion that deforms and expands most outward in the easily deformable portion 711b. The thermal element 80b is arranged on the outer surface of the portion that is most deformed outwardly in the easily deformable portion 711a. Lead wires 70a and 70b are connected to the thermal elements 80a and 80b, respectively. As shown in FIG. 21, the lead wires 70 a and 70 b are disposed so as to be inserted into a lumen 67 formed between the sheath 60 and the tubular member 750, for example. Further, the lead wire 70a connected to the thermal element 80a and the lead wire 70b connected to the thermal element 80b are wired so as to be guided to the distal end side along the outer side or the inner side of the expansion deformation part 710, for example.

The heat element 80c is disposed on the outer surface of the portion that is deformed to expand outward most in the easily deformable portion 721b. The thermal element 80d is disposed on the outer surface of the portion that expands and deforms most outward in the easily deformable portion 721a. Lead wires 70c and 70d are connected to the thermal elements 80c and 80d, respectively. As shown in FIG. 21, the lead wires 70 c and 70 d are disposed so as to be inserted into a lumen 67 formed between the sheath 60 and the tubular member 750, for example. Further, the lead wire 70c connected to the thermal element 80c and the lead wire 70d connected to the thermal element 80d are wired so as to be guided to the distal end side along the outer side or the inner side of the expansion deformable portion 720, for example.

As shown in FIG. 20, the tubular member 750 has a base end portion 753 fixed to the connector 96. The sheath 60 accommodates or protrudes each of the expanded deformation portions 710 and 720 formed at the distal end portion 751 of the tubular member 750 by moving forward and backward. Further, the hand operating section 90 is provided with a port 95 for introducing the guide wire 130 and a communication passage 95 a that communicates the port 95 with the guide wire lumen 747 of the inner tube 740.

According to the ablation catheter 700 according to the present embodiment, similarly to the ablation catheter 100 described above, it is possible to simultaneously perform treatment on a plurality of treatment target sites, and inadvertent displacement of the thermal element 80 occurs. Therefore, it is possible to suitably prevent the narrowed portion from being formed along with the treatment while shortening the treatment time.

Further, the shaft portion is configured by a tubular member 750 in which a plurality of slits 712 and 722 are formed, and the plurality of expansion deforming portions 210 and 220 are induced to expand and deform by the slits 712 and 722 in the tubular member 750. Since the deformable portions 711a, 711b, 721a, and 721b are configured, the expanded deformable portions 710 and 720 can be easily manufactured by processing the tubular member 750 having a relatively simple configuration. Manufacturing costs can be reduced and manufacturing operations can be simplified.

Further, a plurality of easy-to-deform portions 711a and 711b (721a and 721b) formed in pairs at opposite positions in the circumferential direction of the tubular member 750 are provided at different positions in the axial direction of the tubular member 750. It is possible to easily form the expansion deformable portions 710 and 720 having multi-directional deformability in the tubular member 750 so that the thermal elements 80a to 80d can be suitably positioned and arranged with respect to the treatment target site. it can.

The tube further includes an inner tube 740 through which the tubular member 750 is inserted, and the inner tube 740 has a guide wire lumen 747 through which the guide wire 130 can be inserted, so that a plurality of expansion deformable portions 710 and 720 are delivered to the treatment target site. It becomes possible to secure the guide wire lumen 747 used at the time.

Next, a modification of the ablation catheter 700 according to the second embodiment described above will be described. In the modifications described below, the same member numbers are assigned to components that can be configured in the same manner as the members already described, and the description thereof is omitted. Further, configurations that are not particularly mentioned can be configured in the same manner as the respective parts of the ablation catheter 700 according to the above-described embodiment.

<Modification>
The deformable portions 711a and 711b included in the ablation catheter 700 described above were shaped so as to expand at the same position in the axial direction. For example, as shown in FIGS. 24 (A) and 24 (B), The easily deformable portions 711a and 711b can be configured to expand at different positions in the axial direction. With this configuration, the axial distance between the thermal elements 80a and 80b disposed in the easily deformable portions 711a and 711b can be increased, thereby reducing the risk of forming the constricted portion. It becomes possible. Similarly, the easily deformable portions 721a and 721b can be configured to expand at different positions in the axial direction. In addition, each of the thermal elements 80a, 80b, 80c, and 80d can be disposed on the outer surface of the portion of each of the easily deformable portions 711a, 711b, 721a, and 721b that expands and deforms outward most. it can.

The above-described ablation catheter according to the second embodiment and the modifications thereof are not limited to the exemplified configurations. For example, the shape and number of slits, the shape and size of the easily deformable portion, the direction and number of deformation, the number of heat elements disposed in the easily deformable portion, and the like can be appropriately changed. It is also possible to configure the ablation catheters 700 and 800 as a rapid exchange type catheter device. In addition, for example, a configuration in which one or more thermal elements are provided in each of the easily deformable parts (expanded deformable parts) provided in the ablation catheter is shown. However, the number of thermal elements installed is at least 2 for one ablation catheter. It is possible to add an easily deformable portion that is not provided with a heat element, as long as it is provided with at least two.

As described above, the ablation catheter according to the present invention has been described through a plurality of embodiments and modifications. However, the present invention is not limited to the configuration described in the embodiments, and may be appropriately changed based on the description of the scope of claims. Is possible.

As a method of ablation, a method using high-frequency electric energy has been described. However, for example, microwave energy, ultrasonic energy, coherent light such as a laser, heated fluid, cooled fluid, or the like can be used. However, not only heating but also cooling can be performed.

In addition, although an example in which the heating element 80 is configured by a monopolar electrode has been described, a bipolar electrode may be configured by using a plurality of heating elements.

In addition, an example in which the ablation catheter is applied to a treatment method aimed at lowering blood pressure in patients with refractory hypertension has been described. For example, heart failure, renal disease, chronic renal failure, sympathetic hyperactivity, diabetes, metabolic abnormality, arrhythmia It can be applied to the treatment of acute myocardial infarction, cardiorenal syndrome and the like. Further, the disease site (treatment site) to be treated is not limited to the renal artery, and can be applied to, for example, myocardial ablation for treating tachyarrhythmia.

This application is based on Japanese Patent Application No. 2014-186727 filed on September 12, 2014, the disclosure of which is incorporated by reference in its entirety.

10, 310, 410, 510, 610, 710 first expansion deformation section (expansion deformation section),
20, 320, 420, 520, 620, 720 second expansion deformation section (expansion deformation section),
30, 330, 430, 530, third expansion deformation part (expansion deformation part),
50 shaft part,
60 sheath,
70, 70a, 70b, 70c, 70d, 70e, 70f Lead wire,
80, 80a, 80b, 80c, 80d, 80e, 80f heating elements,
90 Hand control unit,
91 operation members,
100, 100 ′, 200, 300, 400, 500, 500 ′, 600, 700, 800 Ablation catheter,
130 guide wire,
651a first ring member,
651b second ring member,
652a, 652b stopper,
711a, 711b, 721a, 721b easily deformable part,
712, 722 slit,
740 inner pipe,
747 Lumen for guide wire,
750 Tubular member.

Claims (12)

A long shaft,
A plurality of expansion deformable portions provided on the tip side of the shaft portion and capable of expanding and contracting;
Two or more thermal elements that are provided in the plurality of expansion deformable portions and have a thermal effect on the living tissue,
The plurality of expansion deforming portions are arranged at different positions in the axial direction of the shaft portion, and can be individually expanded and deformed in different directions intersecting the axial direction of the shaft portion. An ablation catheter made. The ablation catheter according to claim 1, wherein at least one thermal element is provided in each of the plurality of expansion deformable portions. The shaft portion is constituted by a tubular member in which a plurality of slits are formed,
3. The ablation catheter according to claim 1, wherein the plurality of expansion deformable portions are configured by easy deformation portions in which expansion deformation is induced by the slits in the tubular member. The ablation catheter according to claim 3, wherein a plurality of sets of the easily deformable portions formed in pairs at opposite positions in the circumferential direction of the tubular member are provided at different positions in the axial direction of the tubular member. An inner tube for inserting the tubular member;
The ablation catheter according to claim 3 or 4, wherein the inner tube has a guide wire lumen through which a guide wire can be inserted. The extension deformation portion is formed of a linear member that is shaped in advance so as to divide a plane that intersects the axial direction of the shaft portion around the shaft portion when the expansion deformation is performed. The ablation catheter according to claim 2. The ablation catheter according to claim 6, further comprising first to third expanded deformable portions that divide the plane intersecting with each other at an angle of 60 ° in the circumferential direction of the shaft portion. At least one of the plurality of the extended deformation portions is arranged to be movable in the axial direction of the shaft portion,
The ablation catheter according to claim 6 or 7, wherein the shaft portion is provided with a stopper that limits a movement amount of the expansion deformable portion. The ablation catheter according to any one of claims 1 to 8, wherein a plurality of the thermal elements are arranged at different positions in the circumferential direction of the shaft portion for each of the expanded deformable portions. The ablation catheter according to any one of claims 1 to 9, wherein each of the plurality of thermal elements arranged in the plurality of expansion deforming portions is arranged at a different position in the circumferential direction of the shaft portion. 11. The ablation catheter according to claim 10, wherein each of the plurality of thermal elements is arranged at an equal interval in a circumferential direction of the shaft portion. A sheath capable of inserting a plurality of the expanded deformable portions;
By inserting and moving the sheath in the axial direction relative to the plurality of expansion deformation portions, the plurality of expansion deformation portions are inserted into the sheath and the plurality of expansions from the distal end openings of the sheath. A hand operation part provided with an operation member for operating the protrusion of the deformation part,
12. Each of the plurality of expansion deforming portions contracts and deforms as it is inserted into the sheath, and expands and deforms as it protrudes from the distal end opening of the sheath. Ablation catheter.

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