JP2012170777A - Ablation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ablation device capable of cauterizing only a desired site surely for a cardiac tissue with a thickness.SOLUTION: The ablation device 1 to be inserted in a wall portion of the heart to cauterize a cardiac tissue includes: a long body 10; a needle-like electrode 20 mounted on the distal end side of the body 10 to expose the electroconductive electrode surface by a prescribed length D1; and a high-frequency power supply 30 connected with the electrode 20. The prescribed length is the size of only one part of tissue in the thickness direction that can be cauterized in the wall portion of the heart.

Description

  The present invention relates to an ablation device for use in cauterizing a portion of the heart.

Conventionally, as one method for treating arrhythmia such as atrial fibrillation, catheter ablation is performed by cauterizing and calming a part of abnormally excited tissue using a catheter delivered to the heart.
Usually, in catheter ablation, an electrode provided on a catheter is brought into contact with the surface of the myocardium, and a tissue is cauterized by applying a high-frequency current.

  In the ablation where the electrode is brought into contact with the surface of the myocardium, there is a limit to the depth at which ablation can be performed. Therefore, although a relatively thin atrial tissue can be cauterized in the thickness direction, there is a problem that sufficient cauterization is difficult with a relatively thick ventricular tissue.

In order to solve this, Patent Document 1 describes an ablation catheter including an electrode having a needle-like portion and a receiving surface portion.
This catheter can adjust the amount of protrusion of the needle-like part from the receiving surface part by adjusting the screwing length of the needle-like part with respect to the receiving surface part. By energizing, even a thick myocardial tissue can be sufficiently cauterized over the thickness direction.

Japanese Patent Laid-Open No. 5-42166

However, regarding the ablation catheter of Patent Document 1, the present inventor has found the following problems.
In the case of a thick myocardial tissue or the like, the site to be ablated does not always exist in the thickness direction, and often exists only within a certain range in the thickness direction. In such a case, in the ablation catheter of Patent Document 1, since the tissue in which the needle-like portion is inserted is all cauterized along the length direction of the needle-like portion, the tissue that should not be cauterized (particularly the base of the needle-like portion). There is a problem that there is a risk of cauterization up to the part where the end side is located.

  If a tissue that should not be cauterized is cauterized, the cardiac function after the procedure is excessively reduced, which may adversely affect the prognosis of the patient. For this reason, there is a need for a catheter that reliably cauterizes only the target tissue to be cauterized and that does not easily cauterize the normal tissue adjacent to the target tissue.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide an ablation device that can reliably cauterize only a desired site even for a thick heart tissue. To do.

  The present invention relates to an ablation device that is inserted into a heart wall and cauterizes heart tissue, and has a long main body and a conductive electrode surface having a predetermined length on the distal end side of the main body. And a high-frequency power source connected to the electrode portion, and the predetermined length is limited to a part of the tissue in the thickness direction in the heart wall portion. It is a value that can be cauterized.

In the ablation device of the present invention, the electrode part may have an array structure having a plurality of electrodes arranged in the longitudinal direction of the main body.
Moreover, you may further provide the bioelectric potential measurement part connected to the said electrode part so that switching with the said high frequency power supply is possible.

Another ablation device of the present invention is an ablation device that is inserted into a heart wall and cauterizes heart tissue, and exposes a conductive first electrode surface of a predetermined length on the distal end side. A first electrode having a needle-like electrode portion provided and a second electrode having a needle-like electrode portion provided on the distal end side by exposing a conductive second electrode surface by a predetermined length , A biopotential measurement unit connected to at least the first electrode, and a high-frequency power source connected to the second electrode.
In this ablation device, at least one of the first electrode and the second electrode may be formed in a tubular shape having a lumen, and the other may be inserted into the one.

  The second electrode is formed in a tubular shape having a lumen, a conductive surface is exposed a predetermined length from the distal end on the inner surface, and a base end side is insulation-coated, and the first electrode is the second electrode The bioelectric potential measurement unit is connectable to the first electrode and the second electrode, and the first electrode measured by the bioelectric potential measurement unit and the second electrode The relative position between the first electrode and the second electrode may be adjustable based on the impedance between the electrodes.

In the ablation device of the present invention, the electrode portion of the first electrode may include a main electrode having the first electrode surface and a reference electrode insulated from the main electrode.
Moreover, a reference electrode may be provided on the outer peripheral surface on the distal end side, and a guide sheath through which the first electrode and the second electrode are inserted so as to advance and retract may be further provided.
Furthermore, the guide sheath may have an ultrasonic probe at the tip.

  According to the ablation device of the present invention, only a desired site can be cauterized reliably even for a thick heart tissue.

It is a figure which shows schematic structure of the ablation device of 1st embodiment of this invention. It is the figure which has introduced the ablation device into the heart. It is a figure which shows the operation | movement at the time of use of the ablation device. It is an enlarged view which shows the front end side of the ablation device which concerns on 2nd embodiment of this invention. It is sectional drawing in the longitudinal direction of the ablation device. (A)-(d) is sectional drawing in the AA line | wire or DD line | wire of FIG. 5, respectively. It is a figure which shows the operation | movement at the time of use of the ablation device. It is a figure which shows the operation | movement at the time of use of the ablation device. It is a figure which shows the operation | movement which inserts the ablation device in the heart wall. It is an enlarged view which shows the front end side of the ablation device which concerns on 2nd embodiment of this invention. (A)-(c) is a figure which shows the example of the positional relationship of an outer needle electrode and an inner needle electrode all. It is a figure which shows the operation | movement which inserts the ablation device in the heart wall.

A first embodiment of the present invention will be described with reference to FIGS. 1 to 3.
FIG. 1 is a diagram showing a schematic configuration of an ablation catheter (ablation device) 1 of the present embodiment. The ablation catheter 1 is inserted into the heart wall and used for ablation of heart tissue. As shown in FIG. 1, the ablation catheter 1 has a long main body 10 and an electrode portion 20 provided at the distal end of the main body. And a high-frequency power source 30 and a bioamplifier (biological potential measuring unit) 40 that are electrically connected to the electrode unit 20.

  The main body 10 is flexible enough to follow the blood vessel running in the body, and the distal end portion 10A and the proximal end 10B side are electrically connected. As a method of conducting the distal end portion and the proximal end side, the main body 10 may be formed of a conductor, or a conductive layer is formed on a part of a non-conductor member, and the distal end portion and the proximal end are formed by the conductive layer. The side may be made conductive. The outer peripheral surface of the main body is covered with an insulating layer 11. As the insulating layer 11, a known insulating coating or the like can be used.

  The electrode portion 20 is formed in a needle shape with a sharp tip, and the conductive outer peripheral surface (electrode surface) is exposed by a predetermined length D1 in the longitudinal direction of the main body 10. The electrode part 20 is electrically connected to the tip part 10 </ b> A of the main body 10. The main body 10 and the electrode portion 20 may be separate or integrated, but when the tip of a long member made of a conductor is processed into a needle shape, the main body 10 and the electrode portion 20 are integrally formed. Can be simple. The predetermined length D1 described above is a value that can cauterize only a part of the tissue in the thickness direction when inserted into the heart wall in a cauterization treatment described later. In the present embodiment, the dimension D1 is set to 2 to 3 millimeters (mm) in consideration of local cauterization of the ventricular wall.

  The high-frequency power supply 30 has a known configuration for supplying a high-frequency current to the electrode unit 20 during tissue cauterization. The bioamplifier 40 is a known device capable of measuring the potential of a living body, and its output is displayed and stored on a monitor and a storage medium (not shown). The high frequency power supply 30 and the bioamplifier 40 are connected to the base end side of the main body 10 via the switching unit 2 including a switch or the like, and the surgeon operates the switching unit 2 to operate the high frequency power supply 30 and the bioamplifier 40. One of these is alternatively conducted to the main body 20.

Operation during use of the ablation catheter 1 configured as described above will be described.
First, the operator introduces the ablation catheter 1 into the patient's heart using a guiding catheter (not shown) or the like, as in the conventional catheter ablation procedure.

  The surgeon operates the switching unit 2 to connect the main body 10 and the bioamplifier 40 and starts acquiring the potential in the patient's body. Since the potential input to the bioamplifier 40 is mainly composed of the potential in a very narrow area around the electrode unit 20, the target part to be cauterized is identified while checking the output value of the bioamplifier with a monitor or the like. To do. The target region may be identified by combining known potential mapping of the heart surface.

  First, the electrode portion 20 is brought into contact with the surface of the heart 100 to measure the surface potential and roughly measure the target region. When the position of the target site can be roughly specified, the electrode portion 20 of the ablation catheter 1 is inserted into the wall of the heart 100 as shown in FIG. FIG. 2 shows a state where it is inserted into the wall of the right ventricle 111 as an example.

  When the electrode unit 20 is inserted, the surgeon advances and retracts the ablation catheter 1 in the heart wall while confirming the output value of the bioamplifier 40, and specifies the position of the target site in the thickness direction of the heart wall in more detail. At the time of advancing / retreating operation, the tip position of the electrode unit 20 is confirmed, and care is taken so that the ablation catheter 1 does not penetrate the heart wall. The tip position can be determined by X-ray fluoroscopy, but it is preferable to use an ultrasonic image from the viewpoint of resolution and X-ray exposure.

When the detailed specification of the target part is completed, the surgeon positions the electrode unit 20 at the target part. Then, the switching unit 2 is operated to connect the high frequency power supply 30 and the main body 10, and the electrode unit 20 is energized with high frequency. As shown in FIG. 3, the tissue T1 around the electrode portion 20 is denatured and cauterized by the heat accompanying high-frequency energization.
When there are a plurality of target parts, the above operation is repeated, and when the cauterization of all the target parts is completed, the surgeon connects the main body 10 and the bioamplifier 40 and confirms whether or not ablation has been sufficiently performed. After confirmation, the surgeon performs additional ablation as necessary, and when the ablation is sufficiently performed, the ablation catheter 1 is removed and the procedure is completed.

  According to the ablation catheter 1 of the present embodiment, the electrode surface of the electrode portion 20 is exposed for a predetermined length sufficiently small with respect to the thickness of the heart wall, so that the tissue is cauterized over the thickness direction of the heart wall. Instead, it is possible to cauterize only the target part existing in a part in the thickness direction. As a result, the amount of tissue ablation that does not contribute to the treatment can be reduced, and the treatment results, the quality of life (QOL) of the patient, the prognosis, etc. can be improved.

  Further, since the bioamplifier 40 is connected to the main body 10, local potential information inside the heart wall can be obtained from the electrode unit 20 by switching the connection by the switching unit 2. Such information has not been obtained by conventional catheter ablation that mainly identifies the target site by potential mapping of the heart surface. By using the potential information, the target site to be cauterized can be more accurately determined. Can be identified.

  Next, a second embodiment of the present invention will be described with reference to FIGS. The difference between the ablation catheter 51 of the present embodiment and the ablation catheter 1 described above is the mode of the electrode portion. In the following description, components that are the same as those already described are assigned the same reference numerals and redundant description is omitted.

  FIG. 4 is a view showing the electrode portion 52 of the ablation catheter 51, and FIG. 5 is a cross-sectional view of the electrode portion 52. As shown in FIGS. 4 and 5, the ablation catheter 51 is formed in a tubular shape having a lumen, and the electrode portion 52 formed in a needle shape is a first electrode divided in the longitudinal direction of the ablation catheter 51. The array structure includes four ring-shaped electrodes 53, a second electrode 54, a third electrode 55, and a fourth electrode 56. An insulating part 11 is provided between the electrodes 53 to 56.

  6A to 6D are cross-sectional views taken along lines AA, BB, CC, and DD, respectively, in FIG. As shown in FIGS. 5 to 6D, the electrodes 53 to 56 are connected to the conductive portions 53A, 54A, 55A, and 56A, respectively. Each of the conductive portions 53A to 56A extends to the base end side while being insulated from each other, and is connected to a switching portion (not shown). The switching unit of the present embodiment is configured to selectively energize one or more desired electrodes among the electrodes 53 to 56.

  The operation of the ablation catheter 51 configured as described above is substantially the same as that of the ablation catheter 1. When the electrode portion 52 is inserted into a tissue such as a heart wall, the potential between the electrodes can be measured by connecting two arbitrarily selected electrodes and the bioamplifier 40. Therefore, it is possible to adjust the range of the tissue where the potential measurement is performed. Note that at this time, the acquired potential information is an average potential of the tissue located between the electrodes.

Also when cauterizing the target part, the cautery range can be adjusted within a certain range by appropriately selecting the electrode to be energized. For example, as shown in FIG. 7, when only one electrode (FIG. 7 shows the second electrode 54 as an example) is energized, a narrow range of tissue around the electrode can be cauterized.
On the other hand, when all of the electrodes 53 to 56 are energized as shown in FIG. 8, a wider region can be cauterized. Therefore, depending on the thickness dimension of the symmetric portion, the through wall cauterizes the tissue over the thickness direction. It is also possible to perform sex ablation. Furthermore, although not shown in the figure, it is possible to perform ablation with a plurality of ranges separated in the thickness direction as a target part by a single operation by energizing a plurality of spaced apart electrodes.

  Also in the ablation catheter 51 of the present embodiment, by energizing one of the plurality of electrodes of the electrode unit 52, the amount of tissue ablation that does not contribute to the treatment is reduced, as in the ablation catheter 1, and the treatment results and Prognosis and the like can be improved.

  Moreover, since the electrode part 52 is an array structure provided with the some electrodes 53-56 insulated from each other, the ablation range can be adjusted within a fixed range by appropriately selecting electrodes to be energized. Therefore, the ablation range can be adjusted according to the size of the target region, and the time required for the procedure can be shortened.

For introducing the ablation catheter 51 into the heart, as shown in FIG. 9, a guiding catheter 120 having a known ultrasonic probe 121 attached to the distal end may be used. In this way, since the ultrasonic probe 121 for confirming the tip position of the electrode part 52 can be arranged closer to the electrode part 52, a clearer ultrasonic image can be obtained, and the tip position of the electrode part 52 can be further increased. I can capture it reliably. Moreover, when inserting the electrode part 52, the insertion position of the electrode part 52 and the installation position of the ultrasonic probe 121 can be stabilized by fixing the distal end of the guiding catheter 120 to the heart wall. There is also an advantage.
The guiding catheter 120 described above may be used for introducing the ablation catheter 1.

  Next, a third embodiment of the present invention will be described with reference to FIGS. The difference between the ablation catheter 61 of the present embodiment and the ablation catheter 1 described above is that an electrode unit for measuring potential is provided separately from the electrode unit for tissue ablation.

  FIG. 10 is a cross-sectional view showing the distal end side of the ablation catheter 61. The ablation catheter 61 is formed in a tubular shape having a guide sheath 62 and a lumen, and an outer needle electrode (second electrode) 70 inserted into the guide sheath 62 so that the distal end can project and retract, and the distal end can project and retract. And an inner needle electrode (first electrode) 80 inserted through the outer needle electrode 70.

The guide sheath 62 is formed in a tubular shape with an insulator, and has flexibility enough to follow blood vessel travel. The inner diameter of the guide sheath 62 is small at a part on the distal end side, and a stepped portion 63 is formed in the lumen.
A ring-shaped reference electrode 64 is attached to the outer peripheral surface on the distal end side of the guide sheath 62. The reference electrode 64 is connected to the bioamplifier 40 by a wiring 65 disposed within the wall surface of the guide sheath 62 and extending to the proximal end side.

The outer needle electrode 70 is an electrode for performing tissue ablation, has flexibility, a main body 71 inserted through the guide sheath 62, and a needle tube formed of a conductor and attached to the distal end portion of the main body 71. The electrode part 72 is provided. A region having a predetermined length from the tip of the electrode portion 72 is an exposed electrode 73 in which the conductive electrode surface (second electrode surface) is exposed, and the outer peripheral surface on the base end side from the exposed electrode 73 is a conductor. Is covered with an insulating layer 11 so as not to be exposed. Furthermore, the inner surface of the electrode portion 72 is also covered with the insulating layer 11 leaving a region having a predetermined length from the tip. The length of the exposed electrode 73 in the axial direction is set to be approximately the same as the dimension D1 described above.
The electrode part 72 is connected to the high frequency power supply 30 and the bioamplifier 40 via a switching part (not shown) by a wiring 74 extending to the base end side.

  The main body 71 extends to the proximal end side through the guide sheath 62, and the electrode portion 72 can protrude and retract from the distal end of the guide sheath 62 by moving the main body 71 forward and backward. A stopper 75 protruding in the radial direction is provided at a connection portion between the main body 71 and the electrode portion 72. The dimension of the stopper 75 is set such that it cannot enter the lumen on the distal end side of the stepped portion 63 of the guide sheath 62. Therefore, when the outer needle electrode 70 inserted through the guide sheath 62 is advanced with respect to the guide sheath 62, the stopper 75 comes into contact with the stepped portion 63 and cannot move further. That is, the maximum protrusion amount of the outer needle electrode 70 from the guide sheath 62 is defined by the stopper 75.

  The inner needle electrode 80 is an electrode for measuring a tissue potential, has flexibility, is formed of a body 81 inserted through the outer needle electrode 70, and a conductor, and is attached to a distal end portion of the body 81. Needle-shaped electrode portion 82. Like the main body 71 of the outer needle electrode 70, the main body 81 extends to the proximal end side, and the main body 71 can be advanced and retracted to project and retract the electrode portion 72 from the distal end of the guide sheath 62 or the outer needle electrode 70.

  The electrode portion 82 is formed of stainless steel, tungsten, or the like, and the conductive electrode surface (first electrode surface) is exposed by a predetermined length from the tip. The exposed portion has a bipolar (bipolar) structure including a first electrode (main electrode) 83 located on the distal end side and a second electrode (reference electrode) 84 located on the proximal end side of the first electrode 83. I'm taking it. The second electrode 84 is insulated from the first electrode 83 by the insulating layer 85 and extends to the proximal end side, and is covered with the insulating layer 86 except for a part on the distal end side and the proximal end side. The first electrode 83 and the second electrode 84 are connected to the bioamplifier 40 via the switching unit by wires 87 and 88 that are insulated from each other and extend to the proximal end side.

Operation during use of the ablation catheter 61 configured as described above will be described.
The surgeon introduces the ablation catheter 61 to the vicinity of the target site in the heart with the distal ends of the outer needle electrode 70 and the inner needle electrode 80 accommodated in the guide sheath 62.

Subsequently, the surgeon protrudes only the inner needle electrode 80 from the guide sheath 62 and measures the potential between the first electrode 83 and the second electrode 84 while inserting into the heart wall based on the position of the target site. The position is determined and the electrode part 82 is inserted. Since the inner needle electrode 80 is inserted while being supported laterally by the outer needle electrode 70 and the guide sheath 62, the inner needle electrode 80 can be smoothly inserted into the heart wall without causing buckling or the like.
If the inner needle electrode 80 is not rigid enough to be inserted, the inner needle electrode 80 is inserted in the outer needle electrode 70 and inserted into the heart wall, and then the outer needle electrode 70 is retracted. The inner needle electrode 80 may be introduced into the heart wall by removing it from the heart wall.

  The operator specifies the position of the target site in the thickness direction of the heart wall in more detail while measuring the potential in the heart wall with the inner needle electrode 80. Also at this time, since the potential measurement is performed using the first electrode 83 and the second electrode 84 provided close to each other, detailed local potential information can be acquired.

After specifying the target region, the surgeon operates the switching unit to connect the outer needle electrode 70 and the second electrode 84 to the bioamplifier 40 and insert the outer needle electrode 70 into the heart wall. Then, the outer needle electrode 70 is gradually advanced along the inner needle electrode 80.
The impedance between the outer needle electrode 70 and the second electrode 84 varies depending on the shortest distance between them. Therefore, as shown in FIG. 11B and FIG. 11C, when the inner needle electrode 80 protrudes or retreats greatly with respect to the outer needle electrode 70, the impedance increases, and FIG. As shown in a), the impedance becomes the smallest in the state where the portion where the conductive surface of the inner surface of the electrode portion 72 is exposed and the second electrode 84 face each other. The operator carefully advances and retracts the outer needle electrode 70 while fixing the inner needle electrode 80, specifies the position where the impedance is the smallest, and fixes the outer needle electrode 70 at the position.

  Thereafter, in the same manner as when the ablation catheter 1 is used, the outer needle electrode 70 is connected to the high frequency power source 30 and a high frequency current is applied to cauterize the target site. At the time of cauterization, in order to protect the bioamplifier 40, the connection between the inner needle electrode 80 and the bioamplifier 40 is cut and switched to a floating state.

Also in the ablation catheter 61 of this embodiment, only a desired site can be surely cauterized even for a thick heart tissue, as in the ablation catheters of the embodiments described above.
Further, since the inner needle electrode 80 is provided separately from the outer needle electrode 70 for tissue ablation for potential measurement, the potential information in the thickness direction of the heart wall is acquired in more detail, and the position of the target site is determined. It can be specified with high accuracy. Further, since the inner needle electrode has a bipolar structure, the local potential can be measured in detail.

  In addition, since the bioamplifier 40 can be connected to the outer needle electrode 70 and the inner needle electrode 80, the outer needle electrode 70 is advanced and retracted while referring to the impedance between the two, so that the outer needle electrode can be easily and reliably moved. Can be introduced up to the tissue to be ablated.

  In the present embodiment, an example in which the potential measurement is performed between two electrodes of the inner needle electrode and between the inner needle electrode and the outer needle electrode has been described. However, if necessary, the reference electrode 64 provided on the guide sheath 62 and the inner electrode Potential measurement may be performed between the needle electrode 80 and the needle electrode 80.

  Further, instead of the guide sheath 62, a guide sheath 130 including an ultrasonic probe 131 may be used like the above-described guiding catheter 120. At this time, as shown in FIG. 12, if the ultrasonic wave emission surface 131A of the ultrasonic probe 131 is directed in front of the opening 132A of the channel 132 through which the outer needle electrode 70 and the inner needle electrode 80 are inserted, the channel 132 The tips of the inner needle electrode 80 and the outer needle electrode 70 that are projected and inserted into the heart wall can be captured more clearly. The direction of the exit surface 131A may be switchable between the front of the opening 132A and the front of the guide sheath 130.

Furthermore, in this embodiment, the example in which the inner needle electrode is used for potential measurement and the outer needle electrode is used for tissue ablation has been described, but these relationships are reversed, the inner needle electrode is used for tissue ablation, and the outer needle electrode is used for tissue ablation. Each may be used for potential measurement. In this case, after the inner needle electrode is moved to the target tissue, the outer needle electrode may be sufficiently retracted and then the high frequency current may be applied to the inner needle electrode.
Furthermore, instead of the positional relationship in which one of the inner needle electrode and the outer needle electrode is inserted into the other, the inner needle electrode and the outer needle electrode may be configured to run side by side so as to be relatively movable in the axial direction. In this case, the inner needle electrode and the outer needle electrode may not be tubular but may be formed in a needle shape.

  The embodiments of the present invention have been described above. However, the technical scope of the present invention is not limited to the above-described embodiments, and the combinations of the components or the components may be changed without departing from the spirit of the present invention. It is possible to make various changes to or delete them.

  For example, in each of the above-described embodiments, an example in which the ablation catheter is introduced from the inside of the heart has been described. However, by transthoracic access or the like, the ablation catheter approaches the heart from outside the heart through the pericardial sac, It may be inserted into the heart wall.

  Further, a temperature measurement sensor such as a thermocouple or a thermistor may be provided on the electrode to which high-frequency current is applied, and feedback control of the high-frequency current to be supplied may be performed.

  Further, in the electrode part for tissue ablation, a flow path for sending physiological saline for cooling or the like may be formed, and a plurality of communication ports communicating with the flow path may be formed on the outer peripheral surface of the electrode part. In this way, like conventional ablation devices, physiological saline can be supplied to the flow path before and during energization to cool the heat of the electrode section itself, and the impedance of the tissue in contact with the electrode section can also be reduced. It can be lowered and efficient ablation is possible.

In addition, the present invention includes the following technical ideas.
(Additional item 1)
An ablation method using the ablation device according to claim 6 at the beginning of the present application,
Inserting the first electrode into the heart wall in a state of being accommodated in the second electrode, and retracting only the second electrode to remove it from the heart wall, Introducing into the heart wall;
Is provided.
(Appendix 2)
An ablation method using the ablation device according to claim 6 at the beginning of the present application,
Inserting the first electrode into the heart wall and measuring tissue potential;
Identifying a target site for ablation based on the measurement result of the tissue potential, and positioning the first electrode at the target site;
Piercing the second electrode into the heart wall;
Measuring the impedance between the first electrode and the second electrode, and positioning the second electrode at a position where the impedance is minimized;
Is provided.

1, 51, 61 Ablation catheter (ablation device)
DESCRIPTION OF SYMBOLS 10 Main body 20, 52 Electrode part 30 High frequency power supply 40 Bioamplifier (Bioelectric potential measurement part)
53, 54, 55, 56 Electrode 62 Guide sheath 64 Reference electrode 70 Outer needle electrode (second electrode)
72 Electrode unit 80 Inner needle electrode (first electrode)
82 Electrode unit 83 First electrode (main electrode)
84 Second electrode (reference electrode)
100 Heart 130 Guide sheath 131 Ultrasonic probe

Claims (9)

An ablation device inserted into the heart wall to cauterize heart tissue,
A long body,
A needle-like electrode portion provided on the front end side of the main body by exposing a conductive electrode surface by a predetermined length;
A high-frequency power source connected to the electrode part;
With
The ablation device is characterized in that the predetermined length is a value capable of cauterizing only a part of the tissue in the thickness direction in the wall of the heart.   The ablation device according to claim 1, wherein the electrode section has an array structure having a plurality of electrodes arranged in the longitudinal direction of the main body.   The ablation device according to claim 1, further comprising a biopotential measurement unit connected to the electrode unit so as to be switchable with the high-frequency power source. An ablation device inserted into the heart wall to cauterize heart tissue,
A first electrode having a needle-like electrode portion provided on the distal end side by exposing the conductive first electrode surface by a predetermined length;
A second electrode having a needle-like electrode portion provided on the distal end side by exposing the conductive second electrode surface by a predetermined length;
A biopotential measurement unit connected to at least the first electrode;
A high frequency power source connected to the second electrode;
An ablation device comprising:   The ablation device according to claim 4, wherein at least one of the first electrode and the second electrode is formed in a tubular shape having a lumen, and the other is inserted into the one. The second electrode is formed in a tubular shape having a lumen, the conductive surface is exposed for a predetermined length from the tip on the inner surface, and the base end side is insulated and coated,
The first electrode is inserted through the second electrode;
The bioelectric potential measurement unit is connectable to the first electrode and the second electrode, and the impedance between the first electrode and the second electrode measured by the bioelectric potential measurement unit is 6. The ablation device according to claim 4, wherein a relative position between the first electrode and the second electrode is adjustable based on the ablation device.   The ablation device according to claim 6, wherein the electrode portion of the first electrode includes a main electrode having the first electrode surface and a reference electrode insulated from the main electrode.   The ablation device according to claim 6, further comprising a guide sheath having a reference electrode on an outer peripheral surface on a distal end side, through which the first electrode and the second electrode are inserted so as to be able to advance and retreat.   The ablation device according to claim 6, further comprising a guide sheath having an ultrasonic probe at a distal end portion, through which the first electrode and the second electrode are inserted so as to advance and retreat.

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