JP2016007334A - Electrode member for ablation and catheter for ablation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode member for ablation having a novel structure which facilitates connection of a lead wire while avoiding protrusion of a connecting part of the lead wire to a peripheral surface in connecting the lead wire, and a catheter for ablation having a novel structure using the electrode member for ablation.SOLUTION: In an electrode member 12 for ablation for performing a cauterization treatment on an inner surface of a lumen of a human body, a connection piece 63 protruding from an end part on a proximal side in an electrode part 46 extending in a lengthwise direction of the lumen is provided, and a lead wire 44 for power feeding is connected to an inner peripheral surface side of the connection piece 63. In addition, in a catheter 10 for ablation that is inserted in the lumen of the human body, the electrode member 12 for ablation is attached to a distal side.

Description

  The present invention relates to an ablation electrode member for performing an ablation treatment on the inner surface of a lumen such as a blood vessel and an ablation catheter using the ablation electrode member.

  2. Description of the Related Art Conventionally, a treatment is known in which an ablation catheter is inserted into a lumen such as a blood vessel, and an inner surface of the lumen is cauterized. For example, renal denervation catheterization is one of them, focusing on the fact that the sympathetic nerve passing through the surface of the renal artery carries the function of transmitting a signal that regulates blood pressure, and cauterizing the sympathetic nerve by heating Therefore, it is known to treat anti-hypertensive hypertension as antihypertensive treatment.

  In the renal denervation catheterization, an ablation catheter described in JP 2010-509032 (Patent Document 1), JP 2013-510589 (Patent Document 2), or the like is used. Such an ablation catheter is inserted into the renal artery from the femoral artery of the human body through the aorta, and a sympathetic nerve located outside the vascular wall of the renal artery is generated by generating a high-frequency voltage from an ablation electrode member provided on the distal side of the catheter. It is made to cauterize by heating.

  By the way, in the catheter for ablation, the lead wire for supplying electric power from the outside to the electrode member for ablation is required. Such a lead wire is wired along the catheter and connected to the ablation electrode member by welding or soldering.

  However, in order to simultaneously ablate a plurality of lumens with a single ablation catheter, a plurality of ablation electrodes and lead wires must be housed in the catheter, and it is difficult to reduce the outer diameter. There was a risk of burdening patients and practitioners.

Special table 2010-509032 gazette Special table 2013-51089 gazette

  The present invention has been made in the background as described above, and the problem to be solved is to facilitate the lead wire while avoiding the protrusion to the outer peripheral surface when the lead wire is connected. It is an object to provide an ablation electrode member having a novel structure that can be connected to a catheter, and to provide an ablation catheter having a novel structure using the ablation electrode member.

  Hereinafter, the aspect of this invention made | formed in order to solve such a subject is described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible. Further, aspects or technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or an invention that can be understood by those skilled in the art from those descriptions. It should be understood that it is recognized based on thought.

  A first aspect of the present invention relating to an ablation electrode member is an ablation electrode member for performing an ablation treatment on the inner surface of a lumen of a human body, the proximal side of an electrode portion extending in the length direction of the lumen. A connection piece protruding from the end is provided, and a lead wire for power feeding is connected to the inner peripheral surface side of the connection piece.

  In the electrode member for ablation having a structure according to this aspect, since the lead wire is connected to the inner peripheral surface side of the connecting piece protruding from the end portion on the proxy side, the connecting portion of the lead wire is the outer peripheral surface. It does not protrude to the side, and problems such as an increase in diameter of the catheter are avoided. In addition, the connection of the lead wire to the inner peripheral surface side of the connection piece can be easily performed as compared to the case of connecting to the annular inner peripheral surface.

  In addition, it is desirable for the connecting piece to have a width dimension of not more than a half circumference in the circumferential direction, and preferably a width dimension of about 0.1 to 1.0 mm. By making the width dimension 0.1 mm or more, it becomes easy to secure the connecting surface of the lead wire, while by making the width dimension 1.0 mm or less, the connection piece is prevented from being unnecessarily enlarged. .

  According to a second aspect of the present invention relating to the ablation electrode member, in the ablation electrode member according to the first aspect, a fixing annular portion is provided on the proxy side of the electrode portion. While being fixed to a catheter, the said connection piece protrudes from the edge part by the side of the proxy of this cyclic | annular part, and is provided.

  In the ablation electrode member structured according to this aspect, the annular portion can be more easily and stably fixed to the catheter. The annular portion can be fixed to the catheter by, for example, fitting the annular portion by extrapolating the catheter to the catheter, welding, bonding, or the like.

  A third aspect of the present invention relating to an ablation electrode member is the ablation electrode member according to the second aspect, wherein a spiral shape extending between the electrode part and the annular part extends to the outer peripheral surface of the catheter. The part is provided.

  In the electrode member for ablation having the structure according to this aspect, the end of the electrode portion on the proxy side is allowed to be displaced in the approach and separation directions relative to the annular portion based on the deformation of the spiral portion. . Therefore, the change in the axial length due to the displacement of the electrode portion in the direction perpendicular to the axis of the catheter can be absorbed by the deformation of the spiral portion, for example, the operation of pressing the electrode portion against the inner surface of the blood vessel more smoothly It becomes feasible.

  According to a fourth aspect of the present invention relating to the ablation electrode member, in the ablation electrode member according to any one of the first to third aspects, a width dimension of an end portion on a distal side in the electrode portion is reduced. The width dimension of the recording electrode portion changes in the length direction.

  In the ablation electrode member structured according to this aspect, the problem of the increase in diameter caused by fixing the ablation electrode member on the distal side of a catheter or the like that needs to be reduced in diameter when inserted into the lumen. Can be suppressed. On the other hand, by providing the electrode surface in a portion where the width dimension is larger than the end on the distal side in the electrode portion, it is possible to sufficiently secure the area of the electrode surface that is in contact with the inner surface of the lumen. .

  A fifth aspect of the present invention relating to an ablation electrode member is the ablation electrode member according to the fourth aspect, wherein an electrode surface exposed to the outer peripheral surface of the electrode portion without being covered with an insulating layer is provided. In addition, it is provided in a portion having a larger width dimension than the end portion on the distal side.

  In the ablation electrode member structured according to this aspect, the electrode surface is provided on the electrode portion by covering the surface of the electrode portion with an insulating layer and partially removing the insulating layer to expose the electrode portion to the outer peripheral surface. The degree of freedom in design of the position and size of can be ensured.

  According to a sixth aspect of the present invention relating to the ablation electrode member, in the ablation electrode member according to any one of the first to fifth aspects, a plurality of the electrode portions are provided at a predetermined distance in the circumferential direction of the catheter. It is what has been.

  With the ablation electrode member structured according to this aspect, the position and number of electrode surfaces can be set with a greater degree of freedom in the circumferential direction of the catheter.

  On the other hand, a first aspect of the present invention relating to an ablation catheter is an ablation catheter that is inserted into a lumen of a human body, wherein the ablation electrode member according to any one of the first to sixth aspects is a disc. It is attached to the tar side.

  In the ablation catheter having the structure according to the present aspect, by using the ablation electrode member according to the present invention having the specific structure as described above, it is possible to avoid the protrusion of the connecting portion of the lead wire to the outer peripheral surface. Since it can be done, the procedure is facilitated during insertion into the lumen, and the burden on the patient is reduced.

  Also, in this aspect, when the ablation electrode member is provided with a plurality of electrode portions and an annular portion is provided on the proximal side of each electrode portion, the plurality of electrode portions are the same annular portion on the proximal side. By adopting a structure in which the lead wire is extended from the connecting piece provided in the annular portion, it is not necessary to extend the lead wire from each of the plurality of electrode portions. Therefore, the number of wires in the ablation catheter can be reduced, and the diameter can be reduced.

  A second aspect of the present invention relating to an ablation catheter is the ablation catheter according to the first aspect, wherein a distal side end of the electrode part of the ablation electrode member is mounted in an extrapolated state. It is held between the electrode and the cover tube, and is fixed with a lower strength than the end portion of the electrode portion on the proxy side.

  In the ablation catheter structured according to this embodiment, for example, when the electrode part is pressed against the inner surface of the lumen and cauterization is performed and then the catheter is removed from the lumen, even if the electrode part is caught in the lumen, etc. The distal side is preferentially detached from the catheter. As a result, the problem that the electrode part pierces the inner surface of the lumen due to the proximity of the proxy part of the electrode part from the catheter is avoided, and the distal side of the electrode part is detached from the catheter. It is possible to eliminate the hooking of the part to the lumen and to safely remove the portion from the lumen.

  According to a third aspect of the present invention relating to an ablation catheter, in the ablation catheter according to the first or second aspect, a balloon is provided on the distal side, and an ablation electrode member is disposed on the outer periphery of the balloon. The electrode part is arranged.

  In the ablation catheter structured according to this embodiment, the balloon is inflated in the lumen, so that the electrode portion arranged on the outer peripheral side is displaced to the outer peripheral side and is pressed against the inner surface of the lumen, so that the contact state is stable. And can be held. Therefore, the intended cauterization treatment by the electrode portion can be performed more stably.

  In the electrode member for ablation having a structure according to the present invention, a connecting piece protrudes from the end on the proxy side, and a lead wire is connected to the inner peripheral surface side thereof, thereby avoiding protrusion to the outer peripheral surface side. However, it is possible to easily connect the lead wires.

  Further, in the ablation catheter employing the ablation electrode member having such a specific structure, since the protrusion or enlargement of the diameter of the lead wire connection portion is avoided, the procedure is easy when inserting into the lumen. In addition, the burden on the patient can be reduced.

The front view which shows the whole structure of the catheter for ablation as one Embodiment of this invention. The front enlarged view which shows the distal side of the catheter for ablation shown by FIG. 1 in the expansion state of a balloon. It is an enlarged view of the front-end | tip part in FIG. 1, Comprising: III-III sectional drawing in FIG. IV-IV sectional drawing in FIG. VV sectional drawing in FIG. VI-VI sectional drawing in FIG. The enlarged view in the VII-VII cross section of FIG. The enlarged view in the VIII-VIII cross section of FIG. The enlarged view in the IX-IX cross section of FIG. The front view of the electrode member for ablation which comprises the catheter for ablation shown by FIG. The left side enlarged view of the electrode member for ablation shown by FIG. The top view which shows the edge part by the side of the proxy of the catheter for ablation shown by FIG. XIII-XIII sectional drawing in FIG. XIV-XIV sectional drawing in FIG. Explanatory drawing which shows in parallel the electrode part in order to demonstrate the position of the electrode surface in the electrode member for ablation shown by FIG.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings. First, FIGS. 1 to 9 show an ablation catheter 10 as one embodiment of the present invention. The ablation catheter 10 of the present embodiment is inserted into a renal artery as a lumen of a human body, for example, and used to perform cauterization on the renal sympathetic nerve by renal denervation catheterization. The ablation catheter 10 has a structure in which an ablation electrode member 12 for performing cauterization treatment is attached to the inner surface of a renal artery or the like on the distal side of the catheter body 11. In FIG. 1, the distal side of a catheter having a distal end portion inserted into a blood vessel is shown on the left side, and the proxy side having an operation part outside the body is shown on the right side.

  More specifically, the catheter main body 11 has a structure in which a luer hub 16 is provided on the proximal side of the catheter shaft 14. In addition, the luer hub 16 is provided with a wiring connector 18 that branches into a Y shape.

  The catheter shaft 14 has a triple tube structure, and has a cover shaft 20 on the outermost peripheral side. The diameter of the proximal side of the cover shaft 20 is expanded and connected to the luer hub 16. An outer shaft 22 is inserted through the cover shaft 20, and the outer shaft 22 extends outward from an opening on the distal side of the cover shaft 20. Furthermore, an inner shaft 24 is inserted into the outer shaft 22, and the inner shaft 24 extends outward from an opening on the distal side of the outer shaft 22.

  A central lumen 26 is formed on the inner shaft 24, and an inflation lumen 28 for expanding and contracting a balloon 36 described later is formed between the inner shaft 24 and the outer shaft 22. In addition, a wiring lumen 30 for wiring a lead wire 44 and a temperature sensor 42 described later is formed between the outer shaft 22 and the cover shaft 20.

  Each of the shafts 20, 22, and 24 constituting the catheter shaft 14 is formed of a soft material that can be elastically bent and deformed so that it can be easily inserted into a blood vessel. The resin material constituting the cover shaft 20, the outer shaft 22, and the inner shaft 24 is not particularly limited, but is harmless to the human body and has corrosion resistance, moderate elasticity and strength, and easy processing. In consideration of the above, for example, urethane resin, polyolefin, fluororesin, polyamide and the like are preferably used.

  Further, the length and thickness of the catheter shaft 14 are set so that the distal end on the distal side reaches the renal artery via the aorta and is positioned in consideration of conditions such as the insertion position from outside the body into the blood vessel. Is set. For example, when inserted from the brachial artery, radial artery, or femoral artery, the catheter shaft 14 generally has a length of about 400 to 1800 mm. In general, the inner shaft 24 has an inner diameter of 0.3 to 3 mm, while the cover shaft 20 has an outer diameter of about 0.5 to 5 mm.

  Further, the proxy lumen side of the central lumen 26 is communicated with the inner hole of the luer hub 16. On the other hand, a distal tip 32 is fixed to the distal end of the inner shaft 24, and a cover tube 34 is externally fixed to the distal tip 32. The cover tube 34 is preferably made of, for example, Pebax (registered trademark), which is a polyamide elastomer, a urethane resin, a polyester resin, or the like, and can be elastically deformed.

  Furthermore, in this embodiment, a balloon 36 is provided on the distal side of the ablation catheter 10. The balloon 36 has a proximal end opening fixed to the outer peripheral surface of the outer shaft 22 and a distal end side fixed to the outer peripheral surface of the inner shaft 24 on the distal side of the cover shaft 20.

  Further, the distal end side of the inflation lumen 28 opens into the balloon 36, and the proximal end side of the inflation lumen 28 is connected to an inflation port 38 that is branched from the luer hub 16 to the side. By connecting an external pressure fluid conduit to the opening end of the inflation port 38, the pressure fluid is supplied and discharged from the outside through the inflation lumen 28, and the balloon 36 is in an expanded state and a deflated state. It can be controlled.

  The structure of the balloon 36 itself is the same as that employed in various conventionally known catheters for treatment, and is a hollow expansion / contraction structure that can selectively take a small diameter contracted state and a large diameter expanded state. Thus, for example, a non-compliant balloon that contracts and expands by folding and stretching, and a compliant balloon that expands elastically from a contracted state and expands can be appropriately employed.

  Further, inside the balloon 36, a pair of radiopaque markers 40, 40 are attached to the inner shaft 24 by extrapolation. These radiopaque markers 40, 40 are formed of a Pt—Ir alloy or the like, and are, for example, annular or C-shaped. Thereby, the position of the balloon 36 in the blood vessel can be confirmed using X-rays during the treatment.

  Further, a temperature sensor 42 is attached to the balloon 36. As the temperature sensor 42, a platinum resistance thermometer, a thermistor, or the like is suitably employed in addition to a thermocouple. In addition, the detection signal of the temperature sensor is connected to the wiring connector 18 through, for example, the wiring lumen 30. Then, the temperature around the tissue on which the cauterization treatment is performed can be confirmed by an external device connected to the wiring connector 18.

  An ablation electrode member 12 as shown in FIGS. 10 to 12 is attached to the distal side of the catheter body 11 having such a structure. The ablation electrode member 12 has a long shape extending in the length direction of the catheter body 11, and an electrode portion 46, a spiral portion 47, and an annular portion 48 are provided side by side in the length direction.

  The ablation electrode member 12 including the electrode portion 46, the spiral portion 47, and the annular portion 48 can be formed, for example, by subjecting a raw pipe made of a metal pipe to laser processing and cutting it into a predetermined shape. Thereby, the electrode part 46, the helical part 47, and the annular part 48 can be integrally formed. The ablation electrode member 12 is formed of a conductive material, and in particular, by adopting a Ni—Ti alloy, the ablation electrode is made flexible so that the ablation catheter 10 described later can be expanded. It is possible to obtain high followability.

  The electrode portion 46 has a structure in which a plurality of electrode portions 50 linearly extend in the axial direction from an annular base end side connecting portion 49. Each electrode portion 50 has an arcuate curved cross-sectional shape with a center of curvature on the side of the catheter body 11 and extends in a length straddling the balloon 36 in the axial direction. In particular, in this embodiment, as shown in FIGS. 13 and 14, three electrode portions 50 a, 50 b, 50 c are provided, and these electrode portions 50 a, 50 b, 50 c are arranged in the circumferential direction of the catheter body 11. It is arranged at equal intervals.

  Further, each of these three electrode portions 50a, 50b, 50c is provided with a stepped portion at an intermediate portion in the longitudinal direction, and the distal end side of the proximal end side (proximal side) across the stepped portion. The width dimension in the circumferential direction is reduced on the (distal side) side. That is, the distal sides of the electrode portions 50a, 50b, and 50c are narrow tip side electrode portions 52a, 52b, and 52c, respectively, while the proxy side is respectively a wide base end side electrode portion 54a, 54b, and 54c. ing.

  Specifically, the circumferential width dimensions of the base end side electrode portions 54a, 54b, and 54c of the electrode portions 50a, 50b, and 50c are preferably set within a range of 1/16 to 4/16. . On the other hand, the circumferential width dimension of the distal electrode portions 52a, 52b, 52c may be set within a range of 1/5 to 4/5 of the circumferential width dimension of the proximal electrode portions 54a, 54b, 54c. preferable. As a result, it is possible to more advantageously set the electrode surface, which will be described later, the strength and durability of the electrode unit 50, and the deformation characteristics of the electrode unit 50.

  Furthermore, the surface of each electrode portion 50a, 50b, 50c of the electrode portion 46 is covered with the insulating layer 60 over substantially the entire surface. The insulating layer 60 is attached to the electrode portion 46 by, for example, an insulating resin coating or a polymer jacket, and specific materials include fluorinated resin (PFA, FEP), polyimide, polyetheretherketone (PEEK), and the like. Is preferably employed. In the drawing, the gray colored portion is the portion covered with the insulating layer 60. That is, in the present embodiment, the base end side connecting portion 49, the spiral portion 47, and the annular portion 48 are covered with the insulating layer 60 over the entire surface in addition to the electrode portions 50a, 50b, and 50c.

  And in each electrode part 50a, 50b, 50c, the several electrode surface 62 is formed by providing the area | region which does not have the insulating layer 60 partially. In particular, in the present embodiment, a plurality of rectangular window-like openings are formed in the insulating layer 60 in the base end side electrode portions 54a, 54b, 54c of the electrode portions 50a, 50b, 50c. Through the opening, the electrode surface 62 of the electrode portion 46 is provided exposed to the outer peripheral surface.

  The aspect of the electrode surface 62 such as position, number, shape and size is not limited in any way, but a preferred specific example is shown in FIG. In this specific example, no electrode surfaces 62 are overlapped on the same circumference, and only a single electrode face 62 is set substantially on the same circumference. In other words, the plurality of electrode surfaces 62 formed on the electrode portion 46 constituted by the electrode portions 50a, 50b, and 50c are preferably formed so as to be shifted from each other in the length direction and the circumferential direction of the ablation catheter 10. . As a result, the risk of vascular stenosis or the like accompanying the cauterization treatment over the entire circumference of the renal artery can be effectively reduced.

  Furthermore, a spiral portion 47 is provided on the proximal end side of the electrode portion 46 so as to extend spirally in the axial direction from the proximal end side connection portion 49, and on the proximal end side of the spiral portion 47. Is provided with an annular portion 48. The electrode portion 46, the spiral portion 47, and the annular portion 48 are disposed on the same central axis with substantially the same inner and outer diameter dimensions.

  The spiral portion 47 has a substantially coil spring shape in which a plurality of windings are wound with a predetermined axial pitch and lead angle so that elastic deformation is allowed in the axial compression, tension, and bending directions. It has become.

  On the other hand, the annular portion 48 has a cylindrical or annular shape, and extends outward in the axial direction at a part of the circumference (the lower part in FIG. 10) on the axial base end side. The connection piece 63 is integrally formed. The connection piece 63 has a structure in which a part of the peripheral wall of the annular portion 48 extends with an arcuate cross-sectional shape that curves inwardly as it is.

  At least the inner peripheral surface of the connection piece 63 is an exposed surface without the insulating layer 60, and the leading end portion of the lead wire 44 is overlapped with the exposed surface so as to be conductive by welding or brazing. The connection is fixed in a state. In addition, it is desirable that the tip end portion of the lead wire 44 is fixed along the inner peripheral surface of the connection piece 63 while ensuring a large connection area.

  The ablation electrode member 12 having the above-described structure is inserted into the catheter body 11 so that the annular portion 48 on the proximal end side is inserted into the wiring lumen 30 on the distal side of the cover shaft 20. On the other hand, the spiral portion 47 is disposed on the outer shaft 22 protruding from the cover shaft 20, and the electrode portion 46 is disposed on the outer peripheral side of the balloon 36.

  The annular portion 48 is fitted and fixed to the outer peripheral surface of the outer shaft 22 and is positioned in the axial direction. Further, under such a mounted state, the spiral portion 47 and the electrode portion 46 are arranged on the outer peripheral surface of the outer shaft 22 so as to be deformable and displaceable in a non-fixed state.

  Furthermore, the end on the distal side of the electrode portion 46, that is, the tip of each electrode portion 50a, 50b, 50c is inserted into the rear opening of the cover tube 34, and the diameter of the cover tube 34 and the tip tip 32 is Holds between directions. In particular, in the present embodiment, the tip of the electrode portion 46 is inserted between the cover tube 34 and the tip tip 32 and sandwiched in the thickness direction, or the tip of the electrode portion 46 has a diameter due to its own elasticity. The electrode portion is pressed by a predetermined external force by being pressed against the inner peripheral surface of the opening of the cover tube 34 based on the restoring force outward in the direction, or simply fixed by adhesion or welding as necessary. The tip of 46 is detached from the cover tube 34.

  Thereby, each electrode part 50a, 50b, 50c has a small adhesive force at the distal end side compared to each proximal end side integrally formed with the proximal end side connecting part 49 extrapolated to the outer shaft 22. It is fixed to the catheter body 11 by the above. The electrode portions 50 a, 50 b, and 50 c are broken preferentially on the distal end side rather than the proximal end side and are detached from the catheter body 11 by the external force action.

  The lead wire 44 connected to the connection piece 63 extends to the proximal end side in the wiring lumen 30 and is connected to the wiring connector 18. Then, power is supplied from the external device connected to the wiring connector 18 to the electrode portion 46 of the ablation electrode member 12 through the lead wire 44.

  Therefore, the ablation catheter 10 of the present embodiment having the above-described structure is inserted into a predetermined position of the renal artery from the distal side, and power is supplied to the electrode portion 46 of the ablation electrode member 12 through the lead wire 44. Thus, cauterization can be performed on the renal sympathetic nerve in the renal artery. Note that the electrode which is paired with the electrode portion 46 of the ablation electrode member 12 and is given a potential difference is mounted on the surface of the patient's body skin, for example.

  Here, the lead wire 44 for supplying power to the electrode portion 46 is overlapped and fixed to the inner peripheral surface of the connection piece 63 partially protruding on the circumference of the annular portion 48. 44 does not protrude from the outer peripheral surface of the electrode portion 46. In particular, since the electrode member for ablation is thin and it is difficult to connect the lead wire to the end face in the length direction, for example, it is considered that the lead wire is overlapped on the outer peripheral surface of the electrode member for ablation and connected by welding or the like. However, compared to such a case, the outer diameter of the ablation catheter 10 is increased and the local protrusion on the outer peripheral surface is avoided, and the small diameter and smooth insertion into a blood vessel or the like is smooth. A simple outer peripheral surface can be realized.

  Moreover, if the end of the ablation electrode member on the proxy side is a small-diameter cylindrical shape, it is difficult to insert a lead wire into its inner peripheral surface and perform welding or the like, but the connection piece 63 Since it has a substantially tongue-like shape, the lead wire 44 can be easily connected and fixed as compared to inserting and fixing the lead wire 44 to the annular portion 48. In particular, the connecting piece 63 of the present embodiment has a curved cross-sectional shape in which the inner peripheral surface side where the lead wires 44 are superimposed is curved in a concave shape in the circumferential direction. Positioning and holding can be performed stably, and the connection fixing work is further facilitated.

  In addition, since the lead wire 44 connected to the electrode portion 46 extends in the wiring lumen 30 of the catheter shaft 14 and is not located in the central lumen 26, the lead wire 44 is not a guide wire. And a problem that the central lumen 26 is reduced in diameter can be avoided.

  In particular, in the present embodiment, each of the plurality of electrode portions 50 a, 50 b, 50 c arranged on the balloon 36 is connected to the same base end side connecting portion 49, and the base end of the base end side connecting portion 49 is Since the connecting piece 63 and the lead wire 44 are provided in the annular portion 48 on the side, for example, the number of wires in the ablation catheter 10 can be reduced as compared with the case where the lead wire is connected to each of the electrode portions 50a, 50b, 50c. The diameter of the ablation catheter 10 can be reduced.

  Moreover, in this embodiment, since the adhesion strength of the electrode portion 46 to the catheter body 11 is smaller on the distal side than on the proxy side, for example, when the ablation catheter 10 is extracted from the blood vessel after the operation. Even if a large external force is applied to the electrode portion 46 due to catching or the like, the workability of extracting the ablation electrode member 12 from the blood vessel can be satisfactorily maintained by preferentially removing the distal end side.

  Furthermore, in the ablation catheter 10 of the present embodiment, as shown in FIG. 2, the electrode surface 62 of the electrode portion 46 extrapolated to the balloon 36 is formed on the inner surface of the blood vessel using the expansion force of the balloon 36. Can be pressed stably. Therefore, the intended cauterization treatment can be performed more stably.

  Furthermore, the electrode member 12 for ablation according to the present embodiment is provided with a spiral portion 47 that is easily allowed to be elastically deformed between the electrode portion 46 to be cauterized and the annular portion 48 to be fixed. Therefore, in the ablation electrode member 12, bending and expansion / contraction deformation at the spiral portion 47 is facilitated. Therefore, even when the lumen is greatly refracted like the aorta and the renal artery in renal denervation catheterization, the electrode portion 46 can be easily located at a desired location in the lumen. Further, when the balloon 36 expands in the length direction along with the expansion of the balloon 36, the spiral portion 47 follows and expands, so that the electrode portion 46 is stable without causing local distortion or the like. This deformation is realized.

  Further, the electrode portion 46 of the present embodiment has a narrower tip side electrode portion 52a, 52b, 52c than the base end side electrode portions 54a, 54b, 54c. The side electrode portions 52a, 52b, and 52c are easily deformed so that the proximal end side electrode portions 54a, 54b, and 54c are stably pressed against the blood vessel wall.

  In addition, since the distal end electrode portions 52a, 52b, 52c having a narrow width can be compactly bundled at the distal end portion of the ablation catheter 10, they are provided on the wide proximal end electrode portions 54a, 54b, 54c. While sufficiently securing the area of the electrode surface 62, the diameter of the distal end side of the catheter can be substantially reduced, and insertion into a blood vessel or the like can be easily performed.

  As mentioned above, although embodiment of this invention has been explained in full detail, this invention is not limitedly interpreted by description of the above-mentioned embodiment. For example, in the above-described embodiment, in the ablation electrode member 12, the annular portion 48, the spiral portion 47, and the electrode portion 46 are integrally formed. May be formed. In the case of forming separate bodies, it is possible to make the materials of the respective parts different. In the present invention, the spiral portion is not essential, and for example, the annular portion and the electrode portion may be formed directly and continuously. In addition, the connection piece 63 formed separately from the annular portion 48 can be fixed later.

  Moreover, in the said embodiment, although the annular part 48 of the electrode member 12 for ablation was fitted and fixed to the catheter main body 11, you may adhere by adhesion | attachment, welding, etc. FIG.

  Furthermore, in the said embodiment, although the electrode part 46 of the electrode member 12 for ablation was comprised by the three electrode parts 50a, 50b, 50c which had the predetermined separation distance in the circumferential direction, it is not limited to this aspect. . That is, the width dimension (circumferential dimension) of the electrode part, the number of electrode parts, the arrangement interval, and the like are not limited at all. For example, only one electrode part may be formed, or a plurality of electrode parts may be formed. However, it is also possible to arrange them at irregular intervals in the circumferential direction, or to employ a combination of electrode portions having different shapes and sizes.

  Furthermore, in the above-described embodiment, the width dimensions of the electrode portions 50a, 50b, 50c are changed in the length direction to form the distal end side electrode portions 52a, 52b, 52c and the proximal end side electrode portions 54a, 54b, 54c. However, for example, the width may be constant over the entire length of the electrode portion, or the width may be changed in three or more steps. Furthermore, the width dimension may be gradually changed in the length direction to be tapered.

  In the above-described embodiment, each of the electrode portions 50a, 50b, and 50c has a shape that extends straight. However, the shape is not limited to this shape. For example, a predetermined lead is provided in the axial direction along the outer periphery of the catheter body 11. You may extend spirally, curving in an oblique direction with a corner. However, it is not necessary for each electrode part to have the same shape, and a different shape may be adopted for each electrode part.

  Furthermore, in the above-described embodiment, FIG. 15 shows a preferred form of forming the electrode surface 62 formed on each of the electrode portions 50a, 50b, 50c. However, such form is merely an example, The formation aspect of the electrode surface 62 is not limited at all. That is, the plurality of electrode surfaces 62 formed on the electrode portion 46 may be formed on the same circumference, and even in such a case, the size of the electrode surface 62, that is, the size of the opening in the insulating layer 60. By adjusting, the risk of vascular stenosis or the like due to cauterization treatment can be avoided. Furthermore, the opening in the insulating layer 60 is not limited to a rectangular shape, and the electrode surface 60 can be exposed on the outer peripheral surface of the electrode portion 46 with various shapes.

  Moreover, in the said embodiment, although the electrode part 46 was formed with the highly flexible Ni-Ti alloy, it is not limited to this, The contact state to the blood vessel wall inner surface, such as following the expansion of the balloon 36, etc. For example, a conductive elastomer or the like may be used. However, the balloon 36 is not essential in the present invention.

  Furthermore, in the said embodiment, although the front end by the side of the electrode part 46 was inserted in the back opening part of the cover tube 34, it is not limited to this aspect. That is, a mode in which the tip of the electrode portion 46 is embedded in the cover tube is also possible. For example, the tip of the electrode portion 46 may be embedded by heat in the cover tube having a single layer structure, or the inner peripheral side and the outer periphery. For the cover tube having the two-layer structure on the side, the tip of the electrode portion 46 may be inserted between the two layers to weld the two layers.

  The present invention is not only applied to the ablation catheter used for the cauterization of the renal sympathetic nerve in the renal artery, but any of the ablation catheters for various lumens in the body where the ablation treatment is performed. The present invention can be applied.

10: Ablation catheter, 12: Ablation electrode member, 34: Cover tube, 36: Balloon, 44: Lead wire, 46: Electrode part, 47: Spiral part, 48: Annular part, 49: Proximal end side connection part 50a, 50b, 50c: electrode portion, 52a, 52b, 52c: tip side electrode, 54a, 54b, 54c: base end side electrode, 60: insulating layer, 62: electrode surface, 63: connection piece

Claims (9)

An ablation electrode member for performing cauterization treatment on the inner surface of the lumen of a human body,
A connection piece projecting from the end of the proximal side in the electrode portion extending in the length direction of the lumen is provided, and a lead wire for power feeding is connected to the inner peripheral surface side of the connection piece An electrode member for ablation.   An annular part for fixing is provided on the proxy side of the electrode part, the annular part is fixed to the catheter, and the connecting piece is connected to the proximal side edge of the annular part. The electrode member for ablation according to claim 1, wherein is protruded.   The electrode member for ablation according to claim 2, wherein a spiral portion extending on the outer peripheral surface of the catheter is provided between the electrode portion and the annular portion.   The ablation electrode according to any one of claims 1 to 3, wherein a width dimension of the electrode part changes in a length direction so that a width dimension of an end part on a distal side in the electrode part becomes small. Element.   5. The electrode member for ablation according to claim 4, wherein in the electrode portion, the electrode surface exposed to the outer peripheral surface without being covered with the insulating layer is provided in a portion having a larger width dimension than the end portion on the distal side. .   The ablation electrode member according to any one of claims 1 to 5, wherein a plurality of the electrode portions are provided at a predetermined distance from each other in the circumferential direction of the catheter.   An ablation catheter to be inserted into a lumen of a human body, wherein the ablation electrode member according to any one of claims 1 to 6 is attached to a distal side.   An end of the electrode part of the ablation electrode member on the distal side is held between a cover tube attached in an extrapolated state and fixed with a lower strength than an end of the electrode part on the proxy side. The ablation catheter according to claim 7.   The ablation catheter according to claim 7 or 8, wherein a balloon is provided on a distal side, and the electrode portion of the ablation electrode member is disposed on an outer periphery of the balloon.