JP6557507B2 - Medical stimulation electrode - Google Patents

Description

  The present invention relates to a medical electrical stimulation electrode.

2. Description of the Related Art Conventionally, stimulation generators that perform treatment by applying electrical stimulation to biological tissue (linear tissue) such as nerve tissue or muscle are known. Examples of such a stimulus generator include a nerve stimulator, a pain relieving device, an epilepsy treatment device, and a muscle stimulator.
These stimulation generators may be used with medical electrical stimulation electrodes embedded in a living body in order to bring medical electrical stimulation electrodes that transmit electrical stimulation into close contact with a target to be stimulated in the living body.

As this type of medical electrical stimulation electrode, for example, Patent Document 1 discloses a conductive lead body (lead portion) having a proximal end configured to be connected to a pulse generator, and an electric pulse across a blood vessel wall. A tip portion having at least one electrode (stimulation electrode portion) configured to be fed and a lead anchor (electrode support) having an expanded shape are provided. The lead anchor is configured to expand from a folded folded shape to a pre-shaped expanded shape. When in the folded shape, the tip has an effective length that is substantially equal to the effective length of the folded lead anchor.
The leading end of the lead body is coupled to the outside of the lead anchor. In the expanded shape, the lead anchor presses the distal end portion of the lead body against the blood vessel wall, and the distal end portion of the lead body is deployed and fixed in the blood vessel. The lead anchor may be formed from a laser cut tube of superelastic material.

  In Patent Document 1, when the lead anchor to which the tip is attached reaches the stimulation site in the blood vessel adjacent to the nerve to be stimulated, the lead anchor expands and the tip attached to the outside of the lead anchor. Is brought into frictional engagement with the wall of the blood vessel in which the tip including the lead anchor is expanded.

Special table 2010-516405 gazette

The lead anchor described in Patent Document 1 urges an electrode formed on the lead by the lead anchor, and frictionally engages an inner wall of a blood vessel such as a right internal jugular vein.
However, veins are soft and expandable compared to arteries. Furthermore, the inner surface of the vein is smooth and has a property of being easily slipped.
In order to achieve good frictional engagement with the inner wall of the vein, it is necessary to increase the biasing force to the inner wall of the blood vessel in order to increase the frictional force. However, when the urging force increases, the blood vessel swells and deforms. Such interaction between the lead anchor and the blood vessel may cause an unexpected change in the magnitude and direction of the urging force in the normal direction of the blood vessel (the thickness direction of the blood vessel). In this case, the urging force may deviate from a target value for properly pressing the stimulation electrode toward the nerve to be stimulated. Moreover, there is a possibility that the relative positional relationship between the stimulation electrode and the nerve to be stimulated cannot be maintained over time.
If the urging force that presses the stimulation electrode and the nerve to be stimulated is too low, or if the relative position between the stimulation electrode and the nerve to be stimulated changes, the effect of nerve stimulation may be reduced.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a medical electrical stimulation electrode that can stably place a stimulation electrode portion even in a flexible and slippery blood vessel. And

In order to solve the above problems, according to the medical electrical stimulation electrode of the first aspect of the present invention, medical electrical stimulation used by being inserted into the blood vessel to stimulate nerves from the inner wall of the blood vessel. Electrode, which is fixed by a stimulation electrode part for applying electrical stimulation through the inner wall of the blood vessel, a linear lead part through which a wiring electrically connected to the stimulation electrode part is inserted, and a linear elastic member An electrode support that is formed in a bowl shape that is substantially rotationally symmetric about the axis of the electrode, has the stimulation electrode part in a part of the elastic member, and one end in the axial direction is connected to the end of the lead part And a plurality of protrusions protruding from the outer surface of the elastic member that is at least radially outward of the electrode support, the protrusions being distal from the proximal end with respect to the lead portion. Outside the elastic member toward the end Gradually by have a peripheral surface projecting, who from the distal end than backward toward the proximal end from the distal end of the forward direction toward the proximal end is increased with respect to the inner wall The electrode support has a linear portion that is formed by bending a part of the elastic member and has a positional relationship obliquely intersecting the axis as viewed from the radial direction. In addition, at least one of the protrusions further includes a plurality of projecting portions that are included in a natural state and constitute an outer peripheral portion having a maximum outer diameter and are spaced apart from each other in the circumferential direction. Provided in the department .

In the medical electrical stimulation electrode, the outer peripheral surface of the convex portion has a conical curved surface whose outer diameter gradually increases from the outer surface of the elastic member from the proximal end toward the distal end. wherein said projections, in the distal end, the outer surface and the end surface intersecting at an angle of 90 ° or less of said elastic member and said outer peripheral surface, the resilient edge portion intersect over the entire circumference in the circumferential direction of the member May be formed.

  In the medical electrical stimulation electrode, the plurality of convex portions are located at positions where the convex portions on the elastic member adjacent in the circumferential direction are different from each other in the direction along the axis when the diameter of the electrode support is reduced. May be.

  In the medical electrical stimulation electrode, the elastic member may have a coating material containing a resin on an outer peripheral portion, and the plurality of convex portions may be made of the same type of material as the resin.

  In the medical electrical stimulation electrode, the convex portion may be formed on the entire circumference of the outer surface of the elastic member.

  In the medical electrical stimulation electrode, the convex portion may be formed only on the outer surface of the elastic member on the radially outer side of the electrode support.

In the medical electrical stimulation electrode, the plurality of convex portions may include convex portions provided at positions where the distances from the axis of the electrode support are different from each other.

  According to the medical electrical stimulation electrode of the present invention, the stimulation electrode portion can be stably placed even in a flexible and slippery blood vessel.

It is a schematic diagram which shows the whole structure of the medical electrical stimulation electrode of the 1st Embodiment of this invention. It is a schematic diagram which shows the structure of the principal part of the medical electrical stimulation electrode of the 1st Embodiment of this invention. It is a typical perspective view which shows the electrode support fixing member of the lead part of the medical electrical stimulation electrode of the 1st Embodiment of this invention, and the distal end part of an operation sheath. It is a typical front view which shows the structure of the electrode support body of the medical electrical stimulation electrode of the 1st Embodiment of this invention. Is a side view from the direction A1 in FIG. It is a typical perspective view which shows the structure of the elastic member of the medical electrical stimulation electrode of the 1st Embodiment of this invention. It is the top view seen from the A2 direction in FIG. It is the side view seen from the A3 direction in FIG. It is the side view seen from the A4 direction in FIG. It is the side view seen from A5 direction in FIG. It is typical sectional drawing which follows the longitudinal direction of the elastic member of the medical electrical stimulation electrode of the 1st Embodiment of this invention. It is A7-A7 sectional drawing in FIG. It is A8-A8 sectional drawing in FIG. It is typical sectional drawing which shows a mode that the lead part of the medical electrical stimulation electrode of the 1st Embodiment of this invention was inserted in the operation sheath. It is sectional drawing which shows the state by which the electrode support body was inserted in the extraction sheath of the medical electrical stimulation electrode of the 1st Embodiment of this invention. It is typical sectional drawing which shows a mode that the lead part of the medical electrical stimulation electrode of the 1st Embodiment of this invention was inserted in the extraction sheath. It is a schematic diagram which shows the example of the stimulation pulse which the electrical stimulation apparatus used with the medical electrical stimulation electrode of the 1st Embodiment of this invention generate | occur | produces. It is a schematic diagram which shows the state which inserted the electrode support body of the medical electrical stimulation electrode of the 1st Embodiment of this invention in the superior vena cava. It is typical sectional drawing which shows the state which inserted the electrode support body of the medical electrical stimulation electrode of the 1st Embodiment of this invention in the superior vena cava. It is the side view seen from the A9 direction in FIG. It is a partially enlarged view of the A10 parts in FIG. It is a schematic diagram which shows the example of the slack in the lead main body of the medical electrical stimulation electrode of the 1st Embodiment of this invention. It is a schematic diagram which shows the example of the slack in the lead main body of the medical electrical stimulation electrode of the 1st Embodiment of this invention. It is a typical front view which shows the structure of the principal part of the medical electrical stimulation electrode of the 2nd Embodiment of this invention. It is the side view seen from the A11 direction in FIG. It is typical sectional drawing which follows the longitudinal direction of the elastic member of the medical electrical stimulation electrode of the 2nd Embodiment of this invention. It is A12-A12 sectional drawing in FIG. It is typical sectional drawing in alignment with the longitudinal direction of the elastic member of the medical electrical stimulation electrode of the 3rd Embodiment of this invention. It is A13-A13 sectional drawing in FIG. It is a typical front view which shows the structure of the principal part of the medical electrical stimulation electrode of the 4th Embodiment of this invention. It is the side view seen from A14 direction in FIG. It is a typical front view which shows the structure of the principal part of the medical electrical stimulation electrode of the 5th Embodiment of this invention. It is the side view seen from the A15 direction in FIG.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. In all the drawings, even if the embodiments are different, the same or corresponding members are denoted by the same reference numerals, and common description is omitted.

[First Embodiment]
The medical electrical stimulation electrode according to the first embodiment of the present invention will be described.
FIG. 1 is a schematic diagram showing an overall configuration of a medical electrical stimulation electrode according to a first embodiment of the present invention. FIG. 2 is a schematic diagram showing the configuration of the main part of the medical electrical stimulation electrode of the first embodiment of the present invention. FIG. 3 is a schematic perspective view showing the electrode support fixing member of the lead portion of the medical electrical stimulation electrode and the distal end portion of the operation sheath according to the first embodiment of the present invention. FIG. 4 is a schematic front view showing the configuration of the electrode support of the medical electrical stimulation electrode according to the first embodiment of the present invention. FIG. 5 is a side view seen from the A1 direction in FIG. FIG. 6 is a schematic perspective view showing the configuration of the elastic member of the medical electrical stimulation electrode according to the first embodiment of the present invention. FIG. 7 is a plan view seen from the A2 direction in FIG. FIG. 8 is a side view seen from the A3 direction in FIG. FIG. 9 is a side view seen from the A4 direction in FIG. FIG. 10 is a side view seen from the A5 direction in FIG. FIG. 11 is a schematic cross-sectional view along the longitudinal direction of the elastic member of the medical electrical stimulation electrode according to the first embodiment of the present invention. 12 is a cross-sectional view taken along line A7-A7 in FIG. FIG. 13 is a sectional view taken along line A8-A8 in FIG.
In addition, since each drawing is a schematic diagram, the shape and dimension are exaggerated (the following drawings are also the same).

The electrical stimulation electrode 1 (medical electrical stimulation electrode) of this embodiment shown in FIG. 1 is used by being inserted into a blood vessel in order to stimulate nerves from the inner wall of the blood vessel. The electrical stimulation electrode 1 is used together with an electrical stimulation device 70 that applies a stimulation pulse to the electrical stimulation electrode 1.
The electrical stimulation electrode 1 and the electrical stimulation device 70 constitute an electrical stimulation system 200 (medical electrical stimulation system).

  The electrical stimulation electrode 1 includes stimulation electrode portions 10 and 11, a lead portion 20, an electrode support 25, an operation sheath 50, and a removal sheath 60.

The stimulation electrode portions 10 and 11 apply electrical stimulation through the inner wall of the blood vessel. One of the stimulation electrode portions 10 and 11 is used as a plus electrode, and the other is used as a minus electrode.
The lead portion 20 is formed in a linear shape, and passes through a wiring 35 (see FIG. 11) described later that is electrically connected to the stimulation electrode portions 11 and 10. An electrode support 25 to be described later is provided at the first end of the lead portion 20. An electrical stimulation device 70 is connected to the second end portion of the lead portion 20.
The electrode support 25 is formed in a bowl shape that is substantially rotationally symmetric about a certain axis C by linear elastic members 26A, 26B, and 26C. The elastic member 26 </ b> A includes stimulation electrode portions 10 and 11. The electrode support 25 is fixed to the first end of the lead portion 20 via an electrode support fixing member 22 described later.
In the following, when the relative positional relationship between the members of the electrical stimulation electrode 1 along the longitudinal direction of the electrical stimulation electrode 1 is described, the position closer to the electrode support 25 is based on the position closer to the distal side and the position closer to the electrical stimulation device 70. Sometimes called the end side. In the electrode support 25, the distal side with respect to the lead portion 20 may be referred to as the distal end side, and the proximal side with respect to the lead portion 20 may be referred to as the proximal end side.

Both the operation sheath 50 and the extraction sheath 60 are tubular members through which the lead portion 20 is inserted.
The operation sheath 50 is disposed on the distal end side with respect to the extraction sheath 60.
The extraction sheath 60 is disposed on the proximal end side of the lead portion 20.

The lead portion 20 includes a lead body 21, an electrode support fixing member 22, and a connector 23.
The lead body 21 is a tubular member formed of a biocompatible material such as polyamide resin. For example, the outer diameter of the lead body 21 is 0.8 mm or more and 2 mm or less. For example, the length of the lead body 21 is not less than 500 mm and not more than 1000 mm. A wiring 35 (see FIG. 11) is inserted into the conduit of the lead main body 21.
For example, the wiring 35 can be formed by coating a stranded wire made of a nickel cobalt alloy having bending resistance with an electrical insulating material.
Examples of nickel cobalt alloys include 35NLT 25% Ag material, 35NLT 28% Ag material, or 35NLT 41% Ag material.
Examples of the electrical insulating material for the wiring 35 include ETFE (tetrafluoroethylene-ethylene copolymer resin) having a thickness of 20 μm, PTFE (polytetrafluoroethylene resin) having a thickness of 20 μm, and the like. .
Although FIG. 11 shows the wiring 35 connected to the stimulation electrode unit 10, another wiring 35 having the same configuration is also connected to the stimulation electrode unit 11. In the elastic member 26 </ b> A, two wires 35 are arranged in parallel in a coating 34 to be described later on the proximal end side with respect to the stimulation electrode portion 11. These wirings 35 are electrically insulated from each other.

In addition to the wiring 35, a reinforcing member (tension member) such as a metal wire may be disposed or inserted in the pipe of the lead body 21 in order to increase the tensile strength of the lead body 21. When the reinforcing member is disposed and inserted, when the tensile force acts on the lead main body 21, the reinforcing member can bear the load of the tensile force, so that disconnection of the wiring 35 and the like can be prevented.
An appropriate coating may be applied to the surface of the lead body 21. For example, an antithrombotic coating may be applied to the surface of the lead body 21. For example, a coating that improves slidability may be applied to the surface of the lead body 21.

As shown in FIG. 2, the lead body 21 includes a flexible portion 21A and a non-flexible portion 21B in this order from the distal end side toward the proximal end side.
The flexible portion 21 </ b> A is formed within a certain length range from the distal end portion of the lead body 21. The flexible part 21A has first flexibility.
The non-flexible part 21 </ b> B is formed in a range on the base end side excluding the flexible part 21 </ b> A in the lead body 21. The non-flexible portion 21B has a second flexibility that is smaller (more difficult to bend) than the first flexibility.

When the lead main body 21 is hard over the entire length, an external force caused by a patient's movement such as body movement after indwelling is transmitted to the electrode supporting body 25 placed in the blood vessel, and the position movement of the electrode supporting body 25 may occur. When the position movement of the electrode support 25 occurs, the effect of stimulating nerves may be reduced or disappear.
However, when the flexible portion 21A which is a part of the lead body 21 is sufficiently soft, the flexible portion 21A can be installed in a blood vessel. As a result, the external force generated on the base end side is absorbed by the flexible portion 21A, whereby the position movement of the electrode support 25 can be prevented.
The first bendability means bendability that can sag in a blood vessel to such an extent that an external force generated on the proximal end side due to body movement or the like can be absorbed.
In order to give the flexible portion 21A first flexibility, for example, the flexible portion 21A is made of a material having a Shore hardness of about 20D to 40D. In order to give the flexible portion 21A the first flexibility, the length of the flexible portion 21A is set to a length sufficient to absorb external force due to body movement or the like.
The length for obtaining the first flexibility varies depending on the place where the electrode support 25 is placed. For example, when the electrode support 25 is implanted from the internal jugular vein and placed in the superior vena cava, the length of the flexible portion 21A may be about 50 mm to 200 mm. Similarly, when the electrode support 25 is implanted from the subclavian vein, the electrode support 25 may be about 50 mm or more and 250 mm or less. In order to absorb the external force, the longer flexible portion 21A is more preferable. For example, the flexible portion 21A can absorb external force better when the electrode support 25 is implanted from either the internal jugular vein or the subclavian vein.

  The second bendability of the non-flexible portion 21B is such that the force applied in the axial direction of the non-flexible portion 21B at the base end portion of the non-flexible portion 21B can be transmitted to the distal end portion of the non-flexible portion 21B. It means rigidity.

The electrode support fixing member 22 is a tubular member provided at the first end that is the distal end side of the lead body 21. As shown in FIG. 3, a through hole 22 c extending in the longitudinal direction is formed at the center of the electrode support fixing member 22 of the electrode support fixing member 22. Base end portions of elastic members 26A, 26B, and 26C, which will be described later, are inserted on the distal end side of the through hole 22c. A wiring 35 extending from the elastic member 26A is inserted through a base end (not shown) of the through hole 22c.
On the outer peripheral portion of the electrode support fixing member 22, an engaging protrusion 22a protrudes from a cylindrical outer peripheral surface 22b.
The shape of the engagement protrusion 22a is not particularly limited as long as it is a non-circular shape that can be engaged with the distal end portion of the operation sheath 50, which will be described later, around the axis C. In the present embodiment, as an example, a part of the outer peripheral surface 22 b projects outward in the radial direction and has a shape extending in the longitudinal direction of the electrode support fixing member 22. The engagement protrusions 22a in the present embodiment are provided at four locations that divide the outer peripheral surface 22b into four equal parts in the circumferential direction.
The electrode support fixing member 22 can be formed of a metal excellent in biocompatibility, such as titanium.
An antithrombotic coating may be applied to the surface of the electrode support fixing member 22.

The connector 23 electrically connects the wiring 35 and the electrical stimulation device 70.
As the connector 23, for example, a known IS-1 connector or other waterproof connector can be used. However, in the electrical stimulation electrode 1, the connector 23 is not essential, and the wiring 35 inserted into the lead portion 20 and the electrical stimulation device 70 may be directly connected.

As shown in FIGS. 4 and 5, the electrode support 25 includes linear elastic members 26 </ b> A, 26 </ b> B, and 26 </ b> C. The shapes of the elastic members 26A, 26B, and 26C may not be the same as each other. Hereinafter, as an example, the elastic members 26 </ b> A, 26 </ b> B, and 26 </ b> C will be described as an example when they are bent into the same shape.
The elastic members 26 </ b> A, 26 </ b> B, and 26 </ b> C are combined while being shifted in the circumferential direction around an axis C that extends the central axis of the electrode support fixing member 22 toward the distal end side. In the present embodiment, the electrode support 25 is formed in a bowl shape (basket shape) having rotational symmetry about the axis C.
Here, the “saddle shape (basket shape)” means a three-dimensional shape in which a linear body is stretched, which is open to the distal end side and whose outer shape is reduced in diameter toward the proximal end side. The tip side may be substantially cylindrical. The base end side may be a conical shape or a pseudo-conical shape whose outer diameter decreases toward the base end side. The pseudo-conical shape is a shape in which a side surface has a bulge or is narrower than a true cone.
The outer shape of the electrode support body 25 of the present embodiment is substantially cylindrical at the distal end side, and is a pseudo cone shape having a bulge rather than a true cone at the proximal end side. That is, the outer shape of the electrode support 25 of the present embodiment is a bullet type having a top on the base end side.

The elastic members 26 </ b> A, 26 </ b> B, 26 </ b> C are provided with convex portions 30 that protrude from the outer surfaces thereof. The number of the protrusions 30 is not particularly limited, but in the present embodiment, two protrusions 30 are provided on each of the elastic members 26A, 26B, and 26C.
The elastic member 26 </ b> A includes stimulation electrode portions 10 and 11.
The elastic members 26B and 26C have the same outer shape as the elastic member 26A except that the stimulation electrode portions 10 and 11 are not provided.

Hereinafter, the shape of the elastic member 26A will be described unless otherwise specified. Each part of the elastic member 26A is given an uppercase letter “A” at the end of a numeral or a code consisting of a numeral and a lowercase letter. In the elastic members 26B and 26C, portions having the same shape as the elastic member 26A are described by adding uppercase letters “B” and “C” at the end of the numerals common to the elastic members 26A made of numerals or lowercase letters. Omitted.
For example, a bent portion 27fB (27fC) in the elastic member 26B (26C) indicates a portion having the same shape corresponding to the bent portion 27fA in the elastic member 26A.

The elastic member 26A is formed in a three-dimensional loop shape by bending a single linear member having elasticity. Hereinafter, the shape of the elastic member 26A alone will be described. Here, the natural state of the elastic member 26A alone is a state in which an external force does not act on the elastic member 26A or a deformation can be ignored even if it acts.
As shown in FIGS. 6 to 8, the elastic member 26 </ b> A includes a connecting end 26 a </ i> A, a proximal end linear portion 26 b </ i> A, a bent portion 27 f </ i> A, a distal end side linear portion 26 c </ i> A, a bent portion 27 h </ i> A from one end portion toward the other end portion. The base end side linear portion 26dA and the connecting end portion 26eA are provided in this order.

The connecting end portions 26aA and 26eA are portions for fixing the elastic member 26A to the electrode support fixing member 22 and engaging with the lead body 21 via the electrode support fixing member 22. The connecting end portions 26aA and 26eA are each extended linearly along the first axis O1. The connecting end portions 26aA and 26eA are arranged in parallel and close to each other across the first axis O1.
The coupling end portions 26aA and 26eA are arranged so that the first axis O1 is parallel to the axis C.
The method for fixing the connecting end portions 26aA, 26eA and the electrode support fixing member 22 is not particularly limited, and a fixing method such as adhesion, welding, caulking or the like is appropriately selected according to the material of the electrode support fixing member 22. be able to.
When the connecting ends 26aA and 26eA are fixed to the electrode support fixing member 22 by caulking, the shapes of the engagement protrusions 22a and the outer peripheral surface 22b of the electrode support fixing member 22 are simultaneously formed by caulking molds when caulking. May be.

The proximal end side linear portions 26bA and 26dA are U-shaped portions extending as a whole away from the distal ends of the connecting end portions 26aA and 26eA. The proximal end linear portions 26bA and 26dA are disposed on a plane S2 including the first axis O1 and passing through the central axes of the coupling end portions 26aA and 26eA. The proximal-side linear portions 26bA and 26dA are symmetrical with respect to the first axis O1 in the plane S2.
That is, as shown in FIG. 7, the base end side linear portions 26bA and 26dA are inclined toward the distal end side (the left side in the drawing in FIG. 7) so as to be separated from the distal ends of the coupling end portions 26aA and 26eA, respectively. It is extended in the direction. The proximal end side linear portions 26bA and 26dA are gradually separated from the first axis O1 toward the distal end side. The proximal end side linear portions 26bA and 26dA are substantially parallel to the first axis O1 (including the case of being parallel) at the respective distal end portions.

The proximal-side linear portion 26bA can be configured by a curved portion that is convex in a direction away from the first axis O1, a broken line portion, or a combination of the curved portion and the broken line portion.
In the present embodiment, as an example, the shape of the proximal-side linear portion 26bA is such that the proximal-side region b1 close to the connecting end 26aA has a first axis O1 as compared to the distal-side region b2 close to the distal-side linear portion 26cA. The curve shape in which the average rate of change of the slope with respect to is larger is adopted.
The proximal end side linear portion 26dA has a shape symmetrical with the proximal end side linear portion 26bA with respect to the first axis O1.
In this embodiment, the base end side linear portions 26bA and 26dA adopt a shape that is inclined so as to be separated from each other toward the distal end side. For this reason, the distal end side end portions of the base end side linear portions 26bA and 26dA are portions having the maximum width in the direction orthogonal to the first axis O1 of the elastic member 26A in the natural state.

As shown in FIG. 6, the bent portion 27hA is a portion formed in a U shape between the distal end portion of the proximal end side linear portion 26dA and the proximal end portion of the distal end side linear portion 26cA described later. The bent portion 27hA protrudes toward the side opposite to the distal end side linear portion 26cA with respect to the plane S2.
In the present specification, the “U-shape” is not limited to a shape in which two parallel straight portions are connected by an arcuate curved portion. For example, the two straight portions may be parallel and non-parallel, and the curved portion may be curved with a curve other than the arc. Furthermore, the bending part may be comprised by the broken line which consists of a straight line or a curve. For example, as in the present embodiment shown in FIG. 9, a shape (a U-shape) formed by one straight portion bent at the ends of two straight portions may be used.
The bent portion 27hA of the present embodiment includes a first portion h1, a second portion h2, and a third portion h3.

The first portion h1 is a linear portion that is bent at the distal end portion of the proximal-side linear portion 26dA. The first portion h1 may be linear or curved. In the present embodiment, the first portion h1 is linear as an example.
The bending angle φ1 of the first portion h1 may be in a range of 90 ° ± 30 ° (a range of 60 ° or more and 120 ° or less). The length of the first portion h <b> 1 is longer than the longitudinal direction of the stimulation electrode unit 10. An example of the length of the first portion h1 may be 4.5 mm or more and 7.0 mm or less, for example.
Here, the bending angle φ1 is a smaller angle (an angle measured in the bending) among the angles formed by the first portion h1 and the distal end portion of the proximal side linear portion 26dA. However, in FIGS. 9 and 10, the dimension lead line is shown at the position of the vertical angle of the bending angle φ 1 for easy viewing.

The second portion h2 is a linear portion that is bent at the tip in the protruding direction of the first portion h1. The second portion h2 extends in parallel to the plane S2 at a position (see FIG. 7) that is on the extension line of the base-side linear portion 26dA when viewed from the normal direction of the plane S2. The second portion h2 may be linear or curved. In the present embodiment, the second portion h2 is linear as an example.
The length of the 2nd part h2 is good also as 3.0 mm or more and 7.0 mm or less, for example.
A convex portion 30 described later is provided at an intermediate portion in the longitudinal direction of the second portion h2.

The third portion h3 is a linear portion that is bent at the end portion in the extending direction of the second portion h2 and connected to the proximal end portion of the distal end side linear portion 26cA. The third portion h3 may be linear or curved. In the present embodiment, the third portion h3 is linear as an example.
The bending angle φ2 of the third portion h3 may be in a range of 90 ° ± 30 ° (a range of 60 ° to 120 °).
Here, the bending angle φ2 is the smaller of the angles formed by the third portion h3 and the second portion h2. However, in FIGS. 9 and 10, for the sake of easy viewing, the dimension lead line is shown at the position of the isotope angle of the bending angle φ2.
In the present embodiment, the tip of the third portion h3 is located on the plane S2.

In the bent portion 27hA having such a configuration, the stimulation electrode portion 11 is disposed on the first portion h1. The stimulation electrode unit 10 is disposed on the third portion h3. That is, the stimulation electrode portions 10 and 11 are formed in the bent portion 27hA.
The stimulation electrode part 11 is arrange | positioned in the intermediate part of the 1st part h1 so that the longitudinal direction may follow the center axis direction of the 1st part h1. The stimulation electrode unit 10 is disposed in the middle portion of the third portion h3 so that the longitudinal direction thereof is along the central axis direction of the third portion h3.
The detailed configuration of the stimulation electrode portions 10 and 11 will be described after the elastic member 26A is described.

Next, the bent portion 27fA of the elastic member 26A will be described.
As shown in FIG. 10, the bent portion 27fA is a portion formed in a U shape between the distal end portion of the proximal side linear portion 26bA and the proximal end portion of a distal end side linear portion 26cA described later. Similarly to the bent portion 27hA, the bent portion 27fA protrudes on the side opposite to the distal end side linear portion 26cA with respect to the plane S2.
The bent portion 27fA of the present embodiment includes a first portion f1, a second portion f2, and a third portion f3.
The outer shape of the bent portion 27fA may be different from the bent portion 27hA provided at a position facing the plane S1 including the first axis O1 and orthogonal to the plane S2 (see FIG. 6). However, in the present embodiment, the outer shape of the bent portion 27fA is plane-symmetric with the bent portion 27hA with respect to the plane S1.
That is, the first part f1, the second part f2, and the third part f3 have the same outer shape as the first part h1, the second part h2, and the third part h3 in the bent portion 27hA, respectively.
Similar to the second portion h2, a convex portion 30 described later is provided in the middle portion in the longitudinal direction of the second portion f2.
However, unlike the bent portion 27hA, the bent electrode portion 27fA is not provided with the stimulation electrode portions 10 and 11.

As shown in FIG. 6, the distal end side linear portion 26cA is a convex projecting toward the side of the plane S2 from the distal end portion of the third portions f3 and h3 in the bent portions 27fA and 27hA further toward the distal end side. It is a part curved in a shape.
In the present embodiment, as an example, the distal end side linear portion 26cA is disposed on a plane S3 that includes the third axis O3 in the plane S2 and intersects the plane S2 at an angle θ. Moreover, the distal end side linear portion 26cA is formed in a C-shape that is plane-symmetric with respect to the plane S1.
Here, the third axis O3 is an axis that is in the plane S2 and passes through the tip portions of the third portions f3 and h3 and is orthogonal to the first axis O1.
For this reason, the top portion 26gA of the distal end side linear portion 26cA is formed at a position where the second axis O2 formed by the intersection of the planes S1 and S3 intersects the distal end side linear portion 26cA.
The angle θ of the plane S3 may be 5 ° or more and 90 ° or less.

The distal end side linear portion 26cA can be configured by a curved portion, a broken line portion, or a combination of the curved portion and the broken line portion that protrudes in a direction away from the third axis O3.
In the present embodiment, as shown in FIG. 7, the shape of the distal end side linear portion 26cA is, for example, in the proximal end region c1 (c3) close to the bent portion 27fA (27hA). The three portions f3 (h3) are extended in a curved line shape or a straight line shape that is inclined toward the plane S1 from the tip side end portion.
In addition, the distal end side linear portion 26cA has a mountain shape with the apex 26gA as the apex in the distal end side region c2 between the proximal end side regions c1 and c3. The mountain shape in the distal end side region c2 may be, for example, a mountain shape made of a curved line such as an arc or an elliptical arc, or a mountain shape formed by a plurality of broken lines. In the present embodiment, as an example, a curved shape in which the curvature of the top portion 26gA is maximized and a bent portion is formed in the vicinity of the top portion 26gA is adopted.

With such a configuration, the elastic member 26 </ b> A has a shape symmetrical with respect to the plane S <b> 1 except for the stimulation electrode portions 10 and 11.
Here, the internal structure of the elastic member 26A and the configurations of the stimulation electrode portions 10 and 11 and the convex portion 30 will be described.

As shown in FIGS. 11 to 13, the elastic member 26 </ b> A is configured by a linear body in which the outer peripheral surface of the wire portion 33 is covered with a coating 34 (coating material) having electrical insulation.
The cross-sectional shape orthogonal to the longitudinal direction of the wire portion 33 is not particularly limited. For example, the cross-sectional shape orthogonal to the longitudinal direction of the wire portion 33 may be a circle, an ellipse, a square, a rectangle, or the like. The outer diameter or side dimension of the wire portion 33 may be about 0.2 mm or more and 0.5 mm or less.
In this embodiment, the cross section orthogonal to the longitudinal direction of the wire part 33 is formed in a square of 0.3 mm square (side dimension is 0.3 mm), for example. As the material of the wire portion 33, a shape memory alloy, a super elastic wire, or the like can be used.
A resin film may be provided on the outer peripheral surface of the wire portion 33. As a material for the resin film, for example, polyurethane resin, polyamide resin, fluororesin, or the like can be used. The thickness of the resin film may be, for example, 50 μm or more and 500 μm or less.

  A cross section perpendicular to the longitudinal direction of the coating 34 is circular. The outer diameter of the coating 34 is, for example, 0.8 mm. As a material suitable for the coating 34, for example, a resin such as a polyurethane resin or a polyamide resin can be employed.

The stimulation electrode part 10 is formed in a cylindrical shape with a biocompatible metal such as a platinum iridium alloy. The dimensions of the stimulation electrode unit 10 are, for example, an outer diameter of 0.8 mm and a length of 4 mm. A part of the outer peripheral surface of the stimulation electrode unit 10 is exposed from the coating 34 to the outside. Exposed area of the stimulation electrode portion 10 is, for example, may be 1 mm ² or more 5 mm ² or less.
The direction in which the stimulation electrode portion 10 is exposed is a direction facing the radially outer side of the electrode support 25 when the elastic member 26A is assembled to the electrode support 25. The direction toward the radially outer side of the electrode support 25 is a direction away from the axis C along a straight line orthogonal to the axis C.
The stimulation electrode unit 10 and the wire unit 33 are electrically insulated by a coating 34. In order to ensure electrical insulation between the coating 34 and the wire portion 33, a resin insulating member may be provided between the stimulation electrode portion 10 and the wire portion 33.
A wiring 35 is electrically connected to the inner peripheral surface of the stimulation electrode unit 10 by welding or the like. The wiring 35 is disposed in the covering 34 and extends along the wire portion 33, and extends from the base end portion of the coupling end portion 26 e A to the lead portion 20 side.
Although not particularly illustrated, the stimulation electrode unit 11 has the same configuration as the stimulation electrode unit 10 except that the stimulation electrode unit 11 is formed in the first portion h1.
The stimulation electrode portions 10 and 11 are arranged with a gap of at least about 3 mm to 20 mm.

One convex portion 30 is provided for each of the second portions h2 and f2. The arrangement position in the second parts h2 and f2 is not particularly limited, but in the present embodiment, as an example, it is provided in the center of the second parts h2 and f2.
All the convex portions 30 have the same shape. The shape of the convex part 30 is demonstrated with reference to FIG.
As shown in FIG. 11, the convex portion 30 has a first end E1 on the proximal end side and a second end E2 on the distal end side on the outer surface 34a of the elastic member 26A constituted by the outer peripheral surface of the covering 34. Have The surface of the convex portion 30 includes an inclined surface 30b (outer peripheral surface) and an end surface 30a.

The inclined surface 30b is a conical curved surface (tapered surface) whose outer diameter gradually increases from the outer diameter of the outer surface 34a from the first end E1 (proximal end to the lead portion) toward the tip side. The angle formed between the inclined surface 30b and the outer surface 34a is an obtuse angle θ1.
Here, the magnitude | size of the angle which the inclined surface 30b and the outer surface 34a make is an angle between each surface in the cross section containing the central axis line of 26 A of elastic members.
The end surface 30a intersects the outer surface 34a at an angle θ2 at the second end E2. The angle θ2 may be any of an acute angle, a right angle, and an obtuse angle. The shape of the end surface 30a is a conical curved surface (when θ2 is an acute angle or an obtuse angle) or a plane (when θ2 is a right angle) extending outward in the radial direction of the elastic member 26A from the outer surface 34a.
Here, the magnitude | size of the angle which the end surface 30a and the outer surface 34a make is an angle between each surface in the cross section containing the central axis line of 26 A of elastic members.

The inclined surface 30b and the end surface 30a intersect each other to form an edge portion E3 (distal end with respect to the lead portion). The edge portion E3 is formed at the same position as the second end portion E2 in the direction along the central axis of the elastic member 26A when θ2 is a right angle. The edge portion E3 is formed on the tip side of the second end portion E2 in the direction along the central axis of the elastic member 26A when θ2 is an acute angle. The edge portion E3 is formed between the second end portion E2 and the first end portion E1 in the direction along the central axis of the elastic member 26A when θ2 is an obtuse angle.
In the present embodiment, the edge portion E3 is the outermost peripheral portion of the convex portion 30.
The height from the outer surface 34a to the edge portion E3 is h. The height h of the edge portion E3 represents the protruding height of the convex portion 30.

The specific dimension of the convex part 30 can be an appropriate dimension that makes it difficult for the electrode support 25 to move to the distal end side in the blood vessel when the elastic member 26A is assembled as the electrode support 25.
For example, the protrusion height h of the convex part 30 is good also as 0.05 mm or more and 0.5 mm or less.
The axial length d of the protrusion 30 (the length along the central axis of the elastic member 26A from the first end E1 to the edge E3) may be, for example, 0.5 mm or more and 2 mm or less.
For example, θ2 may be 30 ° or more and 150 ° or less. For example, θ1 may be 120 ° or more and less than 180 °.
Hereinafter, as an example, a case where θ2 is 90 ° will be described.

The convex portion 30 may be formed of the same material as the coating 34 or may be formed of a different material. Here, the same material means that the resin types in the classification based on the main component of the resin are the same. That is, the same material is used even when the resin types in the classification based on the main component of the resin are the same and the additives other than the main component resin have different levels of difference. For example, the same material is used when the resin type in the classification based on the main component of the resin is the same and the manufacturer or product grade is different.
The formation method of the convex part 30 is not specifically limited. For example, the convex portion 30 may be bonded to the previously formed coating 34 by welding, adhesion, or the like. For example, when the convex portion 30 is formed of the same material as the coating 34, the convex portion 30 may be formed integrally with the coating 34.
For example, the convex portion 30 may be molded using a mold that forms the shape of the convex portion 30 when the wire portion 33 is covered with the coating 34.
For example, the convex portion 30 may be formed on the outer surface 34a by covering the wire portion 33 with the coating 34 in advance and then placing the material forming the convex portion 30 on the outer surface 34a. As a molding method, the resin material to be the convex portion 30 may be thermally melted and then molded with a molding die. Other molding methods include molding in which a thermosetting resin, an ultraviolet curable resin, or the like is applied and cured in accordance with a molding die.
For example, the protrusion 30 may be formed by removing the coating 34 itself or a resin material adhered on the coating 34 by laser processing or the like.

The elastic members 26A, 26B, and 26C configured as described above have elasticity due to the wire portion 33 and the like.
The elastic members 26A, 26B, and 26C are assembled as the electrode support 25.
As shown in FIG. 5, in the electrode support 25, the elastic members 26 </ b> A, 26 </ b> B, and 26 </ b> C have the first axis O <b> 1 overlapping the axis C. In addition, the top portions 26gA, 26gB, and 26gC of the elastic members 26A, 26B, and 26C are arranged so as to be spaced apart at equal intervals (120 ° intervals) in the circumferential direction with respect to the axis C.
Each of the elastic members 26A, 26B, and 26C is disposed such that the extending direction of the respective distal end side linear portions 26cA, 26cB, and 26cC is directed radially outward with respect to the axis C. As shown in FIG. 5, when viewed from the front end side of the electrode support 25, the elastic members 26A, 26B, and 26C are arranged in the order of the elastic members 26A, 26B, and 26C in the counterclockwise direction.

As shown in FIGS. 4 and 5, the base end side linear portions 26bA and 26dB, the base end side linear portions 26bB and 26dC, and the base end side linear portions 26bC and 26dA are opposed to each other with a gap in the circumferential direction. Placed in position. With this arrangement, the bent portions 27fA and 27hB, the bent portions 27fB and 27hC, and the bent portions 27fC and 27hA have their U-shaped openings facing each other.
The bent portions 27fA and 27hB constitute the overhang portion 40. Similarly, the bent portions 27fB and 27hC constitute an overhang portion 41, and the bent portions 27fC and 27hA constitute an overhang portion 42.
The overhang portions 40, 41, and 42 are portions that restrain the positional deviation of the electrode support 25 by stretching in the blood vessel when the electrode support 25 is disposed in the blood vessel.

In the electrode support 25, adjacent elastic members 26A, 26B, and 26C intersect each other.
The portions where the elastic members 26A and 26B, the elastic members 26B and 26C, and the elastic members 26C and 26A intersect with each other are fixed by the elastic member fixing portion 38.
The elastic member fixing portion 38 can be formed, for example, by bonding the coverings 34 of the elastic members 26A, 26B, and 26C to each other by fusion bonding. Three elastic member fixing portions 38 are provided on the electrode support 25.

The overhang portions 40, 41, 42 constitute an outer peripheral portion having the maximum outer diameter in the electrode support 25 in the natural state. Here, the natural state of the electrode support 25 is an assembled state in which deformation is negligible even if an external force does not act or acts. Since the electrode support 25 is lightweight, deformation due to its own weight can be ignored within the scope of the following description.
In the electrode support 25, the elastic members 26 </ b> A, 26 </ b> B, and 26 </ b> C intersect with each other and are fixed to each other by the elastic member fixing portion 38. For this reason, in the natural state of the electrode support 25, the elastic members 26A, 26B, and 26C may be deformed to some extent from the natural states of the elastic members 26A, 26B, and 26C.

The outer diameter of the electrode support 25 in the natural state is larger than the inner diameter of a blood vessel such as the superior vena cava where the electrode support 25 is placed. For example, when the blood vessel is the superior vena cava, the outer diameter of the electrode support 25 in the natural state can be 20 mm or more and 40 mm or less. The length of the electrode support 25 in the direction of the axis C is, for example, 35 mm.
The base end portions of the elastic members 26A, 26B, and 26C of the electrode support 25 are connected to the electrode support fixing member 22 of the lead portion 20 by welding, adhesive bonding, or caulking.

The electrode support 25 having such a configuration has a bowl shape that is substantially rotationally symmetric about the axis C.
The opening in the bowl shape is formed by a loop formed by the distal end side linear portions 26cA, 26cB, and 26cC extending between the elastic member fixing portions 38.
In the electrode support 25, the three-dimensional shape stretched by the distal end side linear portions 26cA, 26cB, 26cC and the overhang portions 40, 41, 42 is a substantially cylindrical shape.
In the electrode support body 25, the three-dimensional shape stretched by the proximal end side linear portions 26bA, 26dB, 26bB, 26dC, 26bC, and 26dA is a pseudo-cone shape whose diameter decreases from the distal end side toward the proximal end side.

  For example, when an external force acting radially inward is applied to the electrode support 25 configured as described above through the overhang portions 40, 41, and 42, the electrode support 25 has a larger radial diameter than the natural outer diameter. Also reduce the diameter. At this time, the length of the electrode support 25 in the axial direction extends along the axis C. The elastic members 26A, 26B, and 26C adjacent to each other in the circumferential direction each have a reduced interval in the circumferential direction.

Next, the operation sheath 50, the extraction sheath 60, and the electrical stimulation device 70 will be described.
FIG. 14 is a schematic cross-sectional view illustrating a state where the lead portion of the medical electrical stimulation electrode according to the first embodiment of the present invention is inserted into the operation sheath. FIG. 15 is a cross-sectional view illustrating a state where an electrode support is inserted into the extraction sheath of the medical electrical stimulation electrode according to the first embodiment of the present invention. FIG. 16 is a schematic cross-sectional view illustrating a state where the lead portion of the medical electrical stimulation electrode according to the first embodiment of the present invention is inserted into the extraction sheath. FIG. 17 is a schematic diagram illustrating an example of stimulation pulses generated by the electrical stimulation device used together with the medical electrical stimulation electrode according to the first embodiment of the present invention.

The operation sheath 50 shown in FIG. 1 can be operated to advance and retract and rotate the electrode support 25 in the blood vessel when the electrode support 25 is placed in the blood vessel.
The operation sheath 50 includes an engagement portion 53, a sheath body 51, and a hub 52 from the distal end side.

As shown in FIG. 3, the engaging portion 53 is a portion that engages the electrode support fixing member 22 of the lead portion 20 in the circumferential direction at the distal end portion of the operation sheath 50.
The inner peripheral surface of the engaging portion 53 is formed with a concave and convex shape that fits with the concave and convex shape on the outer peripheral portion of the electrode support fixing member 22. In the present embodiment, an outer peripheral surface 22b of the electrode support fixing member 22 and a cylindrical inner peripheral surface 53b that fits slidably in a direction along the axis C are formed on the inner peripheral portion of the engaging portion 53. An engagement groove 53a that fits into the engagement protrusion 22a of the electrode support fixing member 22 is formed.
The engagement groove 53a is formed along the axial direction (longitudinal direction) of the operation sheath 50 corresponding to the engagement protrusion 22a extending in the axial direction (direction along the axis C) of the electrode support fixing member 22. It is extended. Therefore, when the electrode support fixing member 22 is inserted into the engaging portion 53, the electrode support fixing member 22 is engaged with the operation sheath 50 so as to be movable in the axial direction and immovable in the circumferential direction. When the electrode support fixing member 22 and the engaging portion 53 are engaged, the rotational torque can be transmitted to the electrode support 25 by rotating the operation sheath 50 about its axis.

  The engaging portion 53 may be formed integrally with a sheath body 51 to be described later or by deforming the sheath body 51. However, as long as the engaging portion 53 is fixed to the sheath main body 51, the engaging portion 53 may be configured as a separate part from the sheath main body 51.

As shown in FIG. 1, the sheath body 51 is a cylindrical member that inserts the lead portion 20 therein. The sheath main body 51 can slide relative to the lead portion 20.
An engaging portion 53 is disposed coaxially with the sheath body 51 at the distal end portion of the sheath body 51.
A hub 52 described later is fixed to the proximal end portion of the sheath body 51.
The sheath body 51 is formed using a biocompatible material, for example, a polyurethane resin, a polyamide resin, a polyethylene resin, a fluorine resin, or the like.
The sheath body 51 has a torsional rigidity that can transmit the rotational torque applied to the engaging portion 53 by, for example, rotating the base end portion with a hand.

For example, a metal blade using stainless steel, tungsten, or the like may be sealed inside the resin of the sheath body 51. In this case, the rigidity of the sheath body 51 can be improved, and the kink resistance can be improved.
An appropriate film may be provided on the surface of the sheath body 51 as necessary. As an example of a film, the film which improves antithrombogenicity and slidability can be mentioned, for example.
The outer diameter of the sheath body 51 may be, for example, 2.0 mm or more and 2.9 mm or less. The inner diameter of the sheath body 51 may be, for example, 1.0 mm or more and 2.5 mm or less.
The length of the sheath body 51 is such a length that the engaging portion 53 can be disposed in the vicinity of the indwelling position of the electrode support 25. For example, the length of the sheath body 51 may be not less than 300 mm and not more than 400 mm.
When the sheath main body 51 has such a shape and length, in order to obtain torsional rigidity for performing a rotation operation on the electrode support fixing member 22, for example, the hardness of the material used for the sheath main body 51 is a Shore hardness of 55D or more. What is necessary is just about 70D or less. When a metal blade is sealed inside the sheath body 51, a material having a lower Shore hardness can also be used.

As shown in FIG. 14, the hub 52 is a substantially cylindrical member. The hub 52 is provided with a through hole 52a that extends in the axial direction and communicates with the internal space of the sheath body 51, and a side hole 54 that branches from the through hole 52a.
A seal member 55 such as an O-ring is disposed in the through hole 52a. The seal member 55 seals the periphery of the lead body 21 inserted through the operation sheath 50 in a watertight manner to prevent leakage of blood and the like.
A tube 56 is connected to the side hole 54. The other end (see FIG. 1) of the tube 56 is provided with a connector 57 such as a luer lock connector. When the connector 57 is connected to a supply source of a chemical solution such as heparinized physiological saline, the chemical solution such as heparinized physiological saline is supplied into the operation sheath 50 through the tube 56 and the side hole 54. Can do. Note that the tube 56 is not essential, and a connector or the like to which a medication tube or the like can be connected may be provided directly in the side hole 54.

  The hub 52 is disposed outside the patient's body. For this reason, as the material of the hub 52, resins such as polycarbonate and ABS (acrylonitrile butadiene styrene copolymer) resin can be used.

The operation sheath 50 is removed from the blood vessel after placement of the electrode support 25 described later is completed. In this case, it may be removed by using a surgical tool such as scissors, but the operation sheath 50 may be peeled off by hand by adopting a configuration that allows peel-away.
As an example of a configuration that can be peeled away, for example, a configuration in which the orientation direction of the resin is along the axial direction of the operation sheath 50 and the tearing is performed along the axial direction can be given. As an example of a configuration that can be peeled away, a configuration in which a low-strength portion such as a groove serving as a tearing cut line is provided on the outer peripheral portion of the operation sheath 50 along the axial direction of the operation sheath 50 can be cited.

The extraction sheath 60 shown in FIG. 1 is a member that accommodates the electrode support 25 in a reduced diameter state and removes it from the patient's body when the electrode support 25 and the lead portion 20 are extracted. According to the extraction sheath 60, when the electrode support 25 and the lead portion 20 are extracted, the electrode support 25 does not pass through the opening of the blood vessel in the expanded state, and therefore the electrode support 25 damages the blood vessel wall. Can be prevented.
The extraction sheath 60 is placed in the blood vessel together with the electrode support 25 and the lead part 20 during the placement period of the electrode support 25 and the lead part 20.

The extraction sheath 60 includes a sheath body 61 and a hub 62 from the distal end side.
The sheath main body 61 is a cylindrical member through which the lead portion 20 and the reduced-diameter electrode support 25 are inserted. The sheath body 61 is slidable relative to the lead portion 20 and the reduced diameter electrode support 25.
FIG. 15 shows a state where the electrode support 25 is housed in the sheath body 61. In the sheath main body 61, six elastic members 26A, 26B, and 26C having six convex portions 30 are concentrated. Therefore, the inner diameter of the sheath body 61 is set to be larger than the outer diameter of the electrode support 25 in the minimum reduced diameter state.

The outer diameter of the sheath body 61 may be, for example, not less than 2.5 mm and not more than 2.9 mm. The inner diameter of the sheath body 61 may be, for example, 2.0 mm or more and 2.5 mm or less. The length of the sheath main body 61 may be a length that can accommodate the entire electrode support 25 in a reduced diameter state, and a length that allows a part of the proximal end side to come out of the patient's body during indwelling. The length of the sheath body 61 may be, for example, 50 mm or more and 100 mm or less.
The hardness of the sheath body 61 only needs to be able to withstand the axial and radial external forces received from the electrode support 25 when the electrode support 25 is accommodated therein. For example, the hardness of the sheath body 61 may be a Shore hardness of 55D or more and 70D or less.
As will be described later, the extraction sheath 60 is punctured into the patient's neck during use. In order to prevent the sheath body 61 from being folded in the vicinity of the puncture site, the proximal end portion that is in the vicinity of the puncture site may be thickened to improve resistance to the breakage.
A hub 62 described later is fixed to the proximal end portion of the sheath body 51.

As shown in FIG. 16, the hub 62 is a substantially cylindrical member. The hub 62 is provided with a through hole 63 that extends in the axial direction and communicates with the internal space of the sheath body 61, and a side hole 64 that branches from the through hole 63.
A seal member 65 such as an O-ring is disposed in the through hole 63. The seal member 65 seals the periphery of the lead body 21 inserted through the extraction sheath 60 in a watertight manner to prevent leakage of blood or the like.
A tube 66 is connected to the side hole 64. A connector 69 (see FIG. 1) such as a luer lock connector is provided at the other end (not shown) of the tube 66 (not shown). When the connector 69 is connected to a supply source of a chemical solution such as heparin-added physiological saline, the drug solution such as heparin-added physiological saline is supplied into the extraction sheath 60 through the tube 66 and the side hole 64. Can do. The tube 66 is not essential, and a connector or the like to which a medication tube or the like can be connected may be provided directly in the side hole 64.

Further, the hub 62 includes a plate-like wing portion 67 having a thread hooking hole 67a, and a tightening knob 68 provided on the proximal end side.
The wing portion 67 can be used for the purpose of fixing the extraction sheath 60 to the patient's body surface by passing a thread passed through the patient's skin through the thread hooking hole 67a. The thread passed through the skin may be wound around a thread hook groove 62a provided in the hub 62 as necessary.
By fixing the plate-like wing portion 67 to the patient's skin with a tape or the like, the extraction sheath 60 is prevented from rotating around the axis during the treatment period of the electrical stimulation electrode 1.
The tightening knob 68 is screwed to the hub 62. When the tightening knob 68 is screwed into the hub 62, the seal member 65 is compressed. By adjusting the degree of compression of the seal member 65, the sliding resistance between the lead body 21 inserted through the through hole 63 and the extraction sheath 60 can be adjusted. For this reason, if the tightening by the tightening knob 68 is loosened, it is possible to form a slidable state in which the lead body 21 and the extraction sheath 60 can move relative to each other. If tightening by the tightening knob 68 is strengthened, the lead body 21 and the extraction sheath 60 can form a fixed state in which relative movement is impossible.

The material of the sheath body 61 and the hub 62 can be formed of the same material as that of the sheath body 51 and the hub 52 of the operation sheath 50, respectively. Similarly to the sheath main body 51, a metal blade may be enclosed in the sheath main body 61, and an appropriate film may be formed on the surface of the sheath main body 61.
However, since the extraction sheath 60 is extracted from the blood vessel together with the electrode support body 25 and the lead portion 20, it is not necessary to adopt a configuration capable of peeling away.

As shown in FIG. 17, the electrical stimulation device 70 generates a stimulation pulse that is a constant current type or constant voltage type biphasic waveform.
For example, the electrical stimulation device 70 generates a stimulation pulse having a frequency of 10 Hz to 20 Hz (period t is 0.05 sec to 0.1 sec) and a pulse width of 50 μsec to 400 μsec from a plus number to minus a few volts.
The stimulation pulse is transmitted to the stimulation electrode units 10 and 11 through the wiring 35 in the lead unit 20.
The electrical stimulation device 70 can repeatedly apply such a stimulation pulse group with an application time Ton and an application cycle T. For example, the application time Ton may be set to 3 seconds or more and 20 seconds or less, and the application period T may be set to 60 seconds. When it is desired to apply stimulation pulses in a concentrated manner, the application time Ton and the application cycle T may be the same, and continuous application may be performed.

Next, the effect | action of the electrical stimulation electrode 1 is demonstrated with the indwelling operation | movement of the electrical stimulation electrode 1, and the extraction operation | movement.
FIG. 18 is a schematic view showing a state where the electrode support of the medical electrical stimulation electrode according to the first embodiment of the present invention is inserted into the superior vena cava. FIG. 19 is a schematic cross-sectional view showing a state in which the electrode support of the medical electrical stimulation electrode according to the first embodiment of the present invention is inserted into the superior vena cava. 20 is a side view seen from the A9 direction in FIG. Figure 21 is a partially enlarged view of the A10 parts in FIG. FIG. 22 is a schematic diagram illustrating an example of sagging in the lead body of the medical electrical stimulation electrode according to the first embodiment of the present invention. FIG. 23 is a schematic diagram illustrating an example of sagging in the lead body of the medical electrical stimulation electrode according to the first embodiment of the present invention.

First, the operating sheath 50 is moved to the distal end side with respect to the lead portion 20 outside the patient's body, and the engaging portion 53 of the operating sheath 50 is engaged with the electrode support fixing member 22. An electrocardiograph for measuring heart rate is attached to the patient.
As shown in FIG. 18, an opening P2 is formed by making a small incision near the neck P1 of the patient P. A known introducer (not shown) is attached to the opening P2. The introducer is attached so that the tip thereof reaches the superior vena cava P5 (blood vessel) where the electrode support 25 is placed.
The introducer can be torn like the operating sheath 50.

The electrode support 25 and the operation sheath 50 are inserted into the right internal jugular vein P3 (blood vessel) through the introducer. At this time, the electrode support 25 is inserted after being elastically deformed (reduced diameter) to an outer diameter that can be inserted into the introducer.
The electrode support 25 and the operation sheath 50 are inserted by sliding with the inner peripheral surface of the introducer.
At the time of insertion, the positions of the stimulation electrode portions 10 and 11 of the electrical stimulation electrode 1 and the wire portion 33 of the electrode support 25 are confirmed under X-ray fluoroscopy.
FIG. 18 shows a state in which the operation sheath 50 has already been removed in order to show a state after the electrode support 25 is placed.

When the electrode support 25 is pushed out from the tip of the introducer, the electrode support 25 and the operation sheath 50 are introduced into the superior vena cava P5. At this time, the electrode support 25 and the operation sheath 50 may be relatively protruded from the tip of the introducer by moving the introducer backward without moving the electrode support 25.
The diameter of the electrode support 25 that has been reduced in diameter is increased by an elastic restoring force. Since the outer diameter of the electrode support 25 in the natural state is larger than the inner diameter of the superior vena cava P5, the electrode support 25 presses the inner wall of the superior vena cava P5.
Since the stimulation electrode portions 10 and 11 are exposed to the outside in the radial direction of the electrode support 25, they abut against the inner wall of the superior vena cava P5.
In this way, the electrode support 25 is roughly arranged in the superior vena cava P5.

  In the present embodiment, the electrode support 25 is introduced into the superior vena cava from the right internal jugular vein P3, but this is an example. In addition to the right internal jugular vein P3, the electrode support 25 may be introduced into the superior vena cava from the right external jugular vein, the left external jugular vein, the left internal jugular vein, the right subclavian vein, the left subclavian vein, or the like. Good.

  When the electrode support 25 is inserted, a syringe is connected to the connectors 57 and 69 of the operation sheath 50 and the extraction sheath 60. An anticoagulant such as heparinized physiological saline is accommodated in the syringe, and the piston is pushed into the syringe. The anticoagulant is filled into the connectors 57 and 69, the tubes 56 and 66, the hubs 52 and 62, and the sheath bodies 51 and 61.

Adjacent to the superior vena cava P5, the vagus nerve P6 (nerve) to be stimulated is running in parallel.
The operator aligns the electrode support 25 so that the stimulation electrode portions 10 and 11 of the electrode support 25 can stimulate the vagus nerve P6.
The surgeon operates the electrical stimulation device 70 to apply a stimulation pulse to the stimulation electrode units 10 and 11. Stimulation pulses are transmitted to the inner wall of the blood vessel.
In this state, when the surgeon grasps the operation sheath 50 and the proximal end portion of the lead portion 20 and advances or retracts, the distal electrode support 25 moves along the axial direction of the superior vena cava P5. .
Here, the forward movement is a movement for pushing the operating sheath 50 toward the distal end side (distal end side), and the backward movement is a movement for returning the lead portion 20 to the proximal end side (proximal end side).

When the operator grasps the operation sheath 50 and the proximal end portion of the lead portion 20 and rotates the operation sheath 50 around the axis, the engaging portion 53 at the distal end portion of the operation sheath 50 rotates in the same direction. As a result, the electrode support fixing member 22 engaged with the engaging portion 53 also rotates in the same direction, and the lead portion 20 and the electrode support 25 also rotate in the same direction.
As described above, the operator grasps the operation sheath 50 and the proximal end portion of the lead portion 20, and advances, retracts, and rotates, whereby the axial direction and the circumferential direction of the electrode support 25 in the superior vena cava P5 are obtained. Can be adjusted.
This position adjustment is performed while measuring the heart rate with an electrocardiograph attached to the patient P or the like. When the stimulation electrode portions 10 and 11 approach the vagus nerve P6 and are arranged so as to face each other, when the electrical stimulation applied from the stimulation electrode portions 10 and 11 to the vagus nerve P6 increases, the heart rate of the patient P Number is the lowest. The surgeon adjusts the position of the electrode support 25 so that the heart rate is the lowest.

19 and 20 show the state of the electrode support 25 in the superior vena cava P5.
Since the outer diameter of the electrode support 25 in the natural state is larger than the inner diameter of the superior vena cava P5, the electrode support 25 is reduced in diameter than in the natural state, and the outer peripheral portion having a larger outer diameter is the inner wall V of the superior vena cava P5. Abut. In the present embodiment, at least the overhang portions 40, 41, 42 and the vicinity thereof are in contact with the inner wall V.
The overhang portions 40, 41, and 42 press the inner wall V radially outward with an elastic restoring force corresponding to the amount of diameter reduction.
The overhang portions 40, 41, and 42 are each fixed by an elastic member fixing portion 38, form a substantially hexagonal loop shape when viewed from the radial direction, and press the inner wall V. For this reason, the pressing force acts on a substantially hexagonal range, and a stable pressing state is formed.
Furthermore, since the overhang portions 40, 41, and 42 are disposed substantially rotationally symmetrically with respect to the axis C, the overhang portions 40, 41, and 42 press substantially uniformly at positions that equally divide the inner wall V in the circumferential direction.
For this reason, according to the electrode support body 25, the balance of pressing force becomes favorable and it is easy to maintain the stable pressing state.

In the present embodiment, two protruding portions 30 are provided on each of the overhang portions 40, 41, 42. Since the convex part 30 protrudes from the outer surface 34 a of each bent part, the convex part 30 enters the inner wall V on the radially outer side of the electrode support 25.
For example, as shown in FIG. 21, the convex part 30 in the bent part 27hB is in a state in which the inclined surface 30b is in close contact with the inner wall V and the edge part E3 bites into the inner wall V. Although not particularly illustrated, the other convex portions 30 are the same.
For this reason, the sliding resistance of the electrode support body 25 with respect to the inner wall V increases by each convex part 30.
The protruding height of the convex portion 30 increases from the proximal end side toward the distal end side. A step with respect to the outer surface 34a is formed at the edge portion E3 on the most distal side. As an example, the angle θ2 of the end face 30a is 90 °. As a result, the protrusion 30 is unlikely to be caught by the inner wall V in the backward movement (see arrow b in FIG. 21) from the distal end side to the proximal end side.
On the other hand, in the forward movement from the proximal end side to the distal end side (see arrow f in FIG. 21), the convex portion 30 slides in comparison with the backward movement because the edge portion E3 bites into the inner wall V and is caught. Dynamic resistance becomes much larger. When θ2 is an acute angle, the sliding resistance is further increased.
When θ2 is an obtuse angle, by making θ2 <θ1, the sliding resistance of the forward movement can be increased compared to the backward movement.
Since the superior vena cava P5 increases in diameter toward the heart P7, as the electrode support 25 advances, the pressing force decreases, and the indwelling position is likely to fluctuate due to the influence of external force. However, according to the electrode support body 25 of the present embodiment, the indentation position is stabilized even in the superior vena cava P5 because the protrusion 30 increases the sliding resistance at the time of forward movement than at the time of backward movement.

  On the distal end side of the electrode support 25, a loop-shaped opening is formed by the distal end side linear portions 26cA, 26cB, and 26cC. As the electrode support 25 is reduced in diameter, the opening diameter of the opening formed by the distal end side linear portions 26cA, 26cB, and 26cC is also reduced. However, the distal end side linear portions 26cA, 26cB, and 26cC are located in the vicinity of the inner wall V and form an opening close to the inner diameter of the superior vena cava P5. For this reason, the blood flow in the superior vena cava P5 is not easily disturbed.

  As shown in FIG. 20, the proximal-side linear portions 26bA, 26dA, 26bB, 26dB, 26bC, and 26dC on the proximal end side of the electrode support 25 are radiated from the central portion when viewed from the axial direction of the superior vena cava P5. Extend. However, the proximal-side linear portions 26dA and 26bC, the proximal-side linear portions 26bA and 26dB, and the proximal-side linear portions 26dC and 26bB, which are adjacent in the circumferential direction due to the reduced diameter of the electrode support 25, are respectively circumferential directions. To be crowded. For this reason, compared with the case where six base end side linear parts are arrange | positioned at substantially equal intervals, disturbance of a blood flow decreases. In this respect as well, the blood flow in the superior vena cava P5 is not easily disturbed.

When the position of the electrode support 25 is determined, the operator places the electrode support 25 in place.
The operator holds the lead portion 20 and fixes the position of the lead portion 20 in the axial direction. In this state, the operator releases the engagement between the electrode support fixing member 22 and the engaging portion 53 by retracting only the operation sheath 50.
The surgeon further retracts the operation sheath 50. For example, the operator retracts the operation sheath 50 from the electrode support 25 by about 100 mm. At this time, if the operation sheath 50 is retracted and the lead portion 20 is advanced, the displacement of the electrode support 25 can be more reliably prevented. Even if the proximal end side of the lead portion 20 is advanced, the flexible portion 21A is formed on the distal end side of the lead portion 20. Therefore, even if the non-flexible portion 21B on the proximal end side is advanced, the flexible portion 21A sags. Only, the position of the electrode support 25 does not change.
After retracting the operation sheath 50, the operator advances the lead portion 20 and sends it into the superior vena cava P5. This is because an appropriate amount of sag of the flexible portion 21A is formed in the blood vessel of the patient P, so that the length of the lead portion 20 in the blood vessel of the patient P has a margin.
By slackening the flexible portion 21A, for example, even if the lead portion 20 on the proximal end side moves due to body movement of the patient P, the movement of the lead portion 20 on the proximal end side is not performed on the electrode support 25. I don't get it. As a result, the placement position of the electrode support 25 can be stabilized.

The shape of the slack of the flexible portion 21A is not particularly limited. This is because, as long as the flexible portion 21 </ b> A is slack, the external force acting on the lead portion 20 on the proximal end side can be absorbed before being transmitted to the electrode support 25.
For example, as shown in FIG. 22, the flexible portion 21A may sag from point p to point q so as to meander in the blood vessel.
For example, as shown in FIG. 23, the flexible portion 21A may be slacked so as to have a loop portion L between the point p and the point q.
In any case, the actual length of the flexible portion 21A from the point p to the point q is larger than the shortest length along the blood vessel from the point p to the point q.

The shape of the sag and the amount of sag can be confirmed by, for example, the operator observing the shape of the lead part 20 under X-ray fluoroscopy. The amount of sag may be determined so as to absorb the displacement that may cause the lead portion 20 at the base end portion to move.
The surgeon confirms that the necessary slack is obtained and that the position of the electrode support 25 does not change even if the proximal end portion of the lead portion 20 is moved to some extent.

If the electrode support 25 is displaced, the operator advances the operation sheath 50 and engages the engaging portion 53 with the electrode support fixing member 22, so that the position of the electrode support 25 is adjusted. Readjust.
When the electrode support 25 is not displaced, the operator removes the operation sheath 50 from the lead portion 20 and removes it from the blood vessel of the patient P.
For example, if the operation sheath 50 can be torn by hand, the operation sheath 50 is removed by pulling the operation sheath 50 backward while pulling out the operation sheath 50.
If tearing by hand is not possible, for example, the operation sheath 50 may be cut and removed in the longitudinal direction with scissors.

After removing the operation sheath 50, the operator removes the introducer and inserts the removal sheath 60 into the opening P2.
The operator may insert the extraction sheath 60 after removing the introducer, but may insert the extraction sheath 60 simultaneously with removing the introducer as follows.
First, the operator loosens the tightening knob 68 of the extraction sheath 60 to make it slidable. The surgeon advances the extraction sheath 60 along the lead body 21 and inserts the distal end portion of the extraction sheath 60 at the proximal end of the introducer.
Thereafter, the operator removes the introducer sheath 60 by, for example, peeling off the introducer while advancing the extraction sheath 60 into the introducer. Thus, when the removal of the introducer is completed, the extraction sheath 60 is inserted into the right internal jugular vein P3.

When the operator inserts the extraction sheath 60 to an appropriate position, the operator tightens the tightening knob 68 of the extraction sheath 60 to form a fixed state.
Next, for example, the operator applies a thread to the thread hook hole 67a or fixes the wing 67 to the skin of the patient P using an adhesive tape or the like.
Since the tube 66 is connected to the hub 62 of the extraction sheath 60, the surgeon can connect a syringe pump or the like to the connector 69 to administer a liquid such as heparinized physiological saline. For example, when an anticoagulant is administered, the released anticoagulant rides on the blood flow, diffuses in the vicinity of the lead part 20 and the electrode support 25, and thrombus at the position where the lead part 20 and the electrode support 25 are located. Can be reduced.
In this way, the electrode support 25 and the lead part 20 are placed in the blood vessel of the patient P.
The electrode support 25 placed in the superior vena cava P5 can apply nerve stimulation to the patient P by applying electrical stimulation by the electrical stimulation device 70.

When the nerve stimulation treatment necessary for the patient P is completed, the electrical stimulation electrode 1 is removed as follows. In the present embodiment, no surgical reoperation is required to remove the electrical stimulation electrode 1.
Next, the tightening knob 68 of the extraction sheath 60 is loosened to form a slidable state. In this state, the surgeon grasps the lead portion 20 and pulls the lead portion 20 to retract the electrode support 25. At this time, the operator also holds the hub 62 of the extraction sheath 60 so that the extraction sheath 60 does not come out of the right internal jugular vein P3.

When the lead portion 20 is pulled, the electrode support 25 is retracted along the blood vessel. At this time, the electrode support 25 can be smoothly retracted because the base end side is a bowl-like shape and the convex portion 30 is not caught by the inner wall of the blood vessel in the backward movement.
When the electrode support 25 is retracted to the distal end portion of the extraction sheath 60, the electrode support 25 is drawn into the sheath body 61. The electrode support 25 is reduced in diameter along the inner peripheral surface of the sheath body 61 and is accommodated in the extraction sheath 60.

When the electrode support 25 is housed in the sheath body 61, the operator releases the fixation between the hub 62 of the removal sheath 60 and the skin of the neck P1 by cutting the thread. This operation may be performed before the tightening knob 68 of the extraction sheath 60 is loosened.
Thereafter, the operator pulls out the extraction sheath 60 from the right internal jugular vein P3 through the opening P2. In this way, since the sheath body 61 having a constant outer diameter passes only through the opening P2, the electrode support 25 can be pulled out without expanding the blood vessel wall of the opening P2. That is, as the electrode support 25 is pulled out from the opening P2 alone, the diameter of the electrode support 25 does not expand and push the blood vessel wall of the opening P2 when passing through the opening P2. Can be removed without giving.
When the electrical stimulation electrode 1 is removed, the surgeon performs a general hemostatic treatment such as suturing or pressing on the skin of the puncture portion, and ends the treatment.

According to the electrical stimulation electrode 1 of the present embodiment, when the electrode support 25 is inserted into a blood vessel such as the superior vena cava P5, the electrode support 25 is reduced in diameter so that the overhang portions 40, 41, 42, etc. The inner wall of the blood vessel is pressed radially outward. The stimulation electrode portions 10 and 11 exposed to the outside in the radial direction of the electrode support 25 in the overhang portion 42 are in close contact with the inner wall of the blood vessel.
In such a contact state, the contact between the stimulation electrode portions 10 and 11 and the blood is suppressed, so that the electrical stimulation applied between the stimulation electrode portions 10 and 11 can be prevented from leaking to the blood side. .
The stimulation electrode units 10 and 11 can apply electrical stimulation indirectly without directly contacting the vagus nerve P6 by applying electrical stimulation to the vagus nerve P6 via the inner wall of the blood vessel. For this reason, electrical stimulation can be given with minimal invasiveness.

Furthermore, the electrical stimulation electrode 1 includes the protruding portions 30 on the overhang portions 40, 41, and 42. Since the convex portion 30 projects radially outward from the outer surface 34a, the vicinity of the outer edge portion E3 bites into the inner wall of the flexible blood vessel. For this reason, the sliding resistance of the electrode support 25 with respect to the inner wall of the blood vessel at the indwelling position increases.
According to the electrical stimulation electrode 1, the indwelling position of the electrode support 25 can be more stabilized as compared with the case where the outer surface 34a does not have the convex portion 30.
In particular, the convex portion 30 increases the sliding resistance of the forward movement more than the backward movement in the blood vessel when the magnitude of the angle θ2 is smaller than the magnitude of the angle θ1.
In this case, the convex part 30 can suppress the positional deviation due to the forward movement that is likely to occur when the convex part 30 is placed in the superior vena cava P5 or the like, where the inner diameter gradually increases toward the heart P7. In the convex part 30, especially when the angle θ2 is an acute angle or a right angle, the positional deviation due to the forward movement can be remarkably suppressed as compared with the case where the angle θ2 is an obtuse angle.
On the other hand, when the electrode support 25 is retracted at the time of position adjustment or retracted at the time of removal, the sliding resistance by the convex portion 30 is small. For this reason, the electrical stimulation electrode 1 is excellent in operability in the indwelling operation and the extraction operation.
According to the electrical stimulation electrode 1, the stimulation electrode portions 10 and 11 can be stably placed even in a flexible and slippery blood vessel.

In recent years, in the field of treatment of heart failure, it is becoming clear that the prognosis is worsened when chronic heart failure is hated. It has become known that circulatory dysregulation can be corrected by using a tissue stimulation system that directly applies electronic intervention to the autonomic nerve.
By using the electrical stimulation electrode 1 of the present embodiment, it is possible to reduce arrhythmia and remodeling phenomenon that occur after reperfusion treatment during acute myocardial infarction. By electrically stimulating the vagus nerve and continuously lowering the heart rate for a period of time after reperfusion treatment, the heart load can be reduced and cardiac remodeling can be reduced.

[Second Embodiment]
A medical electrical stimulation electrode according to a second embodiment of the present invention will be described.
FIG. 24 is a schematic front view showing the configuration of the main part of the medical electrical stimulation electrode according to the second embodiment of the present invention. FIG. 25 is a side view seen from the A11 direction in FIG. FIG. 26 is a schematic cross-sectional view along the longitudinal direction of the elastic member of the medical electrical stimulation electrode according to the second embodiment of the present invention. 27 is a cross-sectional view taken along line A12-A12 in FIG.

As shown in FIG. 24, the electrostimulation electrode 2 (medical electrostimulation electrode) of the present embodiment is replaced with an electrode support 25 instead of the electrode support 25 of the electrostimulation electrode 1 of the first embodiment. 80. The electrode support 80 can be used in place of the electrode support 25 in the electrical stimulation system 200 of the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

The electrode support 80 is different from the electrode support 25 in that the electrode support 80 includes a protrusion 81 instead of the protrusion 30.
The convex part 81 protrudes from the outer surface of the elastic members 26A, 26B, and 26C, like the convex part 30. The convex portion 81 is different from the convex portion 30 in the arrangement position, the arrangement number, and the protruding shape.
As shown in FIGS. 24 and 25, two convex portions 81 are arranged at positions where the top portions 26gA, 26gB, and 26gC are sandwiched in the distal end side linear portions 26cA, 26cB, and 26cC. Although each arrangement position is not particularly limited, in the present embodiment, as an example, the arrangement positions are arranged closer to the base end than the midpoint between each top and the elastic member fixing portion 38. The convex portions 81 on the distal end side linear portions 26cA, 26cB, and 26cC are arranged on the same circumference around the axis C as an example.

  Furthermore, the convex part 81 is arrange | positioned in the same position as the convex part 30 in the said 1st Embodiment. That is, one convex portion 81 is disposed on each of the second portions f2 and h2 of the bent portions 27fA, 27hA, 27fB, 27hB, 27fC, and 27hC. The convex portions 81 on the second portions f2 and h2 are arranged on the same circumference around the axis C as an example.

  Further, the convex portions 81 are arranged one by one at positions close to the distal ends of the base end side linear portions 26bA, 26dA, 26bB, 26dB, 26bC, and 26dC. The convex portions 81 on the base end side linear portions 26bA, 26dA, 26bB, 26dB, 26bC, and 26dC are arranged on the same circumference around the axis C as an example.

The total number of convex portions 81 of the electrode support 80 is 18.
The arrangement position of each convex part 81 in this embodiment is selected from the range which contacts the inner wall of the blood vessel reliably when the electrode support 80 is placed in the blood vessel. The range of reliable contact with the inner wall of the blood vessel may be determined in advance by examining the deformation of the electrode support 81 with respect to the shape of the blood vessel at the indwelling position through experiments or simulations.
The arrangement interval of the protrusions 81 on the elastic member (the length between adjacent protrusions 81) may be, for example, 5 mm or more and 30 mm or less.

The shape of each convex part 81 is mutually the same. The length of the convex portion 81 in the axial direction may be approximately the same as or different from the length of the convex portion 30 of the first embodiment.
Below, the structure of the convex part 81 is demonstrated taking the convex part 81 provided in the bending part 27hA shown in FIG.
As shown in FIG. 26, the convex part 81 in the bent part 27hA is composed of a plurality of protrusions arranged apart from each other along the axial direction of the elastic member 26A. In the present embodiment, the convex portion 81 includes protrusions 81X, 81Y, and 81Z from the distal end side (the left side in the figure in FIG. 26) toward the proximal end side (the right side in the figure in FIG. 26). The shapes of the protrusions 81X, 81Y, and 81Z may be different, but are the same as each other in the present embodiment. Hereinafter, the shape of the protrusion 81X will be described, and the corresponding portions of the protrusions 81Y and 81Z will be denoted by the same reference numerals and description thereof will be omitted.

  The protrusion 81X has a first end e1 on the proximal end side and a second end e2 on the distal end side on the outer surface 34a of the elastic member 26A. The surface of the protrusion 81X includes an inclined surface 81b (outer peripheral surface), an end surface 81a, and a side surface 81c.

The inclined surface 81b is a conical curved surface (tapered surface) whose outer diameter gradually increases from the outer diameter of the outer surface 34a from the first end e1 (proximal end to the lead portion) toward the tip side. An angle formed by the inclined surface 81b and the outer surface 34a is an obtuse angle ψ1. The method of measuring ψ1 is the same as θ1 in the first embodiment.
An edge e4 having a height h4 from the outer surface 34a is formed at the outermost peripheral portion of the inclined surface 81b by intersecting with a side surface 81c described later. The edge part e4 extends on a circumference coaxial with the central axis of the elastic member 26A.

The end surface 81a intersects the outer surface 34a at an angle ψ2 at the second end e2. The magnitude of ψ2 is the same as θ2 in the first embodiment. The shape of the end surface 81a is a conical curved surface (when ψ2 is an acute angle or an obtuse angle) extending from the outer surface 34a radially outward of the elastic member 26A or a plane (when ψ2 is a right angle). The method of measuring ψ2 is the same as θ2 in the first embodiment.
At the outermost peripheral portion of the end surface 81a, an edge portion e3 (distal end with respect to the lead portion) having a height from the outer surface 34a of h3 (however, h3 ≧ h4) is formed by intersecting a side surface 81c described later. Yes. The edge part e3 extends on a circumference coaxial with the central axis of the elastic member 26A.
In the present embodiment, the heights h3 and h4 are such that the edge portion e4 is positioned radially outward from the straight line connecting the first end portion e1 and the edge portion e3 in the cross section passing through the central axis of the bent portion 27hA. Dimensions.

A side surface 81c is formed between the edge portions e3 and e4.
The side surface 81c is a cylindrical surface coaxial with the central axis of the elastic member 26A (when h3 = h4) or a conical surface coaxial with the central axis of the elastic member 26A (when h3> h4).
In the present embodiment, the angle ψ3 between the inclined surface 81b and the surface of the side surface 81c in the vicinity of the edge portion e4 is 180 ° or more. That is, the inclination with respect to the outer surface 34a is gentler on the side surface 81c than on the inclined surface 81b.
In the present embodiment, the entire side surface 81c or the edge portion e3 constitutes the outermost peripheral portion of the protrusion 81X.

The specific dimension of the protrusion 81X can be an appropriate dimension that makes it difficult for the electrode support 90 to move to the distal end side in the blood vessel when the elastic member 26A is assembled as the electrode support 90.
For example, the height h3 of the edge part e3 may be 0.05 mm or more and 0.5 mm or less.
The axial length d1 of the protrusion 81X (the length along the axial direction of the elastic member 26A from the first end e1 to the edge e3) is the axial length of the protrusion 81 and the protrusions 81X, 81Y, 81Z. It can set suitably according to arrangement | positioning space | interval.
For example, ψ2 may be 30 ° or more and 150 ° or less. For example, ψ1 may be 120 ° or more and less than 180 °.

The arrangement interval d2 of the protrusions 81X, 81Y, 81Z (distance from the first end e1 of one protrusion to the second end e2 of the other protrusion) adopts an appropriate dimension capable of forming the protrusions 81X, 81Y, 81Z. can do. In this embodiment, as an example, d2 <d1.
The protrusions 81X, 81Y, and 81Z having such a configuration can be formed by the same material and forming method as the convex portion 30.

  According to the electrical stimulation electrode 2 of the present embodiment, the electrode support 80 in which the elastic members 26A, 26B, and 26C are assembled is provided as in the first embodiment. For this reason, the electrode support 80 can be placed in a blood vessel such as the superior vena cava P5 to perform electrical stimulation in the same manner as the electrical stimulation electrode 1.

In the electrical stimulation electrode 2, the electrode support 80 includes more convex portions 81 than the convex portions 30.
Each convex portion 81 includes protrusions 81X, 81Y, 81Z. Since each of the protrusions 81X, 81Y, and 81Z includes an end surface 81a and an edge portion e3 like the convex portion 30, the sliding resistance of the electrode support 80 with respect to the inner wall of the blood vessel increases as in the convex portion 30.
Further, the convex portions 81 are distributed and arranged in places where the positions in the direction along the axis C are different in the electrode support 80. For this reason, even if the deformation | transformation state at the time of diameter reduction of the electrode support body 80 changes, the probability that the convex part 81 will remove | deviate from the inner wall of the blood vessel reduces.
According to the electrical stimulation electrode 2, the placement position of the electrode support 80 can be made more stable than the electrical stimulation electrode 1.

Further, the protrusions 81X, 81Y, 81Z in the electrical stimulation electrode 2 have a quadrilateral cross section along the axial direction of the elastic member. For this reason, in the protrusions 81X, 81Y, 81Z, the edge portion e3 on the distal end side is formed by intersecting the inclined surface 81b with the side surface 81c whose inclination with respect to the outer surface of the elastic member is shallow or parallel to the outer surface. On the other hand, in the convex part 30 of the said 1st Embodiment, the cross section along the axial direction of an elastic member is a triangle.
Therefore, in the projections 81X, 81Y, and 81Z, even if each length d1 is shorter than the length d of the convex portion 30, the angle near the edge portion e3 is equal to the angle near the convex portion 30 edge portion E3. Can be larger than
As a result, the load on the inner wall of the blood vessel due to biting in the edge portion e3 is further reduced. And since the intensity | strength of edge part e3 can be improved, it is easy to prevent damage to protrusion 81X, 81Y, 81Z.

  According to the electrical stimulation electrode 2, the stimulation electrode portions 10 and 11 can be stably placed even in a flexible and slippery blood vessel.

[Third Embodiment]
A medical electrical stimulation electrode according to a third embodiment of the present invention will be described.
FIG. 28 is a schematic cross-sectional view along the longitudinal direction of the elastic member of the medical electrical stimulation electrode of the third embodiment of the present invention. 29 is a cross-sectional view taken along line A13-A13 in FIG.

As shown in FIG. 1, the electrical stimulation electrode 3 (medical electrical stimulation electrode) of this embodiment includes an electrode support 90 instead of the electrode support 25 of the electrical stimulation electrode 1 of the first embodiment. . The electrode support 90 can be used in place of the electrode support 25 in the electrical stimulation system 200 of the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

The electrode support 90 is different from the electrode support 25 in that a convex portion 91 is provided instead of the convex portion 30.
The convex portion 91 protrudes from the outer surface of the elastic members 26A, 26B, and 26C, similarly to the convex portion 30. The protrusion 90 is different from the protrusion 30 in the protruding shape.
Convex part 91 is formed only in a part of the circumferential direction, whereas convex part 30 is formed on the entire circumference of outer surface 34a (see FIG. 29). The position where the convex portion 91 is formed is on the outer surface 34 a that is radially outward with respect to the axis C of the electrode support 90.

  The shape of each convex part 91 is mutually the same. Below, the structure of the convex part 91 is demonstrated taking the convex part 91 provided in the bending part 27hA shown to FIG. FIG. 28 is a cross-sectional view in a plane including the axis C of the electrode support 90 and the central axis of the bent portion 27hA.

  As shown in FIG. 28, the convex portion 91 has a first end E4 on the proximal end side and a second end E5 on the distal end side on the outer surface 34a of the elastic member 26A constituted by the outer peripheral surface of the covering 34. Have The surface of the convex portion 91 includes an inclined surface 91b (outer peripheral surface) and an end surface 91a.

The inclined surface 91b is a partially conical curved surface whose outer diameter gradually increases from the outer diameter of the outer surface 34a toward the distal end side from the first end E4. The angle formed by the inclined surface 91b and the outer surface 34a is the obtuse angle θ1 as in the first embodiment.
Here, the size of the angle formed by the inclined surface 91b and the outer surface 34a is an angle between the surfaces in the cross section including the axis C of the electrode support 90 and the central axis of the bent portion 27hA.
The end surface 91a intersects the outer surface 34a at the second end E5 at the same angle θ2 as in the first embodiment. The shape of the end surface 91a is a conical curved surface (when θ2 is an acute angle or an obtuse angle) or a flat surface (when θ2 is a right angle) extending outward in the radial direction of the elastic member 26A from the outer surface 34a.
Here, the size of the angle formed by the end surface 91a and the outer surface 34a is an angle between the surfaces in the cross section including the axis C of the electrode support 90 and the central axis of the bent portion 27hA.

The inclined surface 91b and the end surface 91a intersect at the same position as the second end portion E5 or on the tip side with respect to the second end portion E5 to form an edge portion E6.
The inclined surface 91b intersects the outer surface 34a and intersects at the outer peripheral portion on the side opposite to the axis C. The intersection E7 (see FIG. 29) has a U-shape that opens to the tip side when viewed from the radially outer side facing the axis C. The intersecting portion E7 is located in the semicircular portion on the back side with respect to the axis C on the outer surface 34a (the semicircular portion on the upper side in the drawing in FIG. 29).
The maximum height from the outer surface 34a to the edge portion E6 is h, as in the first embodiment. However, the height from the outer surface 34a to the edge E6 decreases toward the intersection E7 and becomes 0 at the intersection E7.
The convex portion 91 having such a configuration can be formed by the same material and forming method as the convex portion 30.

  According to the electrical stimulation electrode 3 of the present embodiment, the electrode support 80 in which the elastic members 26A, 26B, and 26C are assembled is provided as in the first embodiment. For this reason, the electrode support 80 can be placed in a blood vessel such as the superior vena cava P5 to perform electrical stimulation in the same manner as the electrical stimulation electrode 1.

In the electrical stimulation electrode 3, the electrode support 90 is provided with the convex portion 91 only in the radially outer region with respect to the axis C. The protruding shape of the convex portion 91 is the same as that in the first embodiment in the radial direction of the electrode support 90.
The convex portion 91 in the present embodiment has a protruding shape obtained by removing the radially inner protruding portion that does not contact the inner wall of the blood vessel from the convex portion 30 in the first embodiment. Accordingly, the convex portion 91 can increase the sliding resistance of the electrode support 90 similarly to the convex portion 30 only by reducing the amount of biting into the blood vessel in the vicinity of the intersection E7.
According to the electrical stimulation electrode 3, the placement position of the electrode support 90 can be made more stable than when the convex portion 91 is not provided.
According to the electrical stimulation electrode 3, the stimulation electrode portions 10 and 11 can be stably placed even in a flexible and slippery blood vessel.

According to the electrical stimulation electrode 3, the convex portion 91 can be formed more easily and inexpensively because the amount of resin per piece is smaller than that of the convex portion 30.
Further, the convex portion 91 is formed only on the radially outer side of the electrode support 90. In other words, the elastic members 26A, 26B, and 26C are formed in the semicircular region on the back side with respect to the axis C along the axial direction of each outer surface 34a. The convex portion 91 does not protrude in the circumferential direction of the electrode support 25.
For this reason, even if the electrode support 90 is reduced in diameter and the interval between the elastic members 26A, 26B, and 26C adjacent in the circumferential direction with respect to the axis C is narrowed, the convex portion 91 is adjacent to the adjacent elastic member or the adjacent convex portion 91. Does not interfere with. As a result, the electrode support 90 is reduced to a smaller diameter than the electrode support 25. Therefore, the amount of force required to pull the electrode support 90 into the extraction sheath 60 at the time of extraction can be reduced compared to the electrode support 25.
Further, since the blood contact surface of the electrode support 90, that is, the axis C side along the axial direction of each outer surface 34a of the elastic members 26A, 26B, and 26C has a smooth structure without projections, thrombus is hardly generated.

[Fourth Embodiment]
A medical electrical stimulation electrode according to a fourth embodiment of the present invention will be described.
FIG. 30 is a schematic front view showing the configuration of the main part of the medical electrical stimulation electrode according to the fourth embodiment of the present invention. FIG. 31 is a side view seen from the direction A14 in FIG.

As shown in FIG. 30, the electrical stimulation electrode 4 (medical electrical stimulation electrode) of the present embodiment is an electrode instead of the electrode support 25 of the electrical stimulation electrode 1 of the first embodiment. A support 100 is provided. The electrode support 100 can be used in place of the electrode support 25 in the electrical stimulation system 200 of the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

As shown in FIGS. 30 and 31, the electrode support 100 includes six convex portions 30 as in the first embodiment. The electrode support 100 is different from the electrode support 25 only in the arrangement position of the convex portion 30.
In the first embodiment, the arrangement positions of the protrusions 30 are the same in the axial direction of the electrode support 25, whereas the arrangement positions of the protrusions 30 in the present embodiment are mutually the electrode support 100. Is shifted in the axial direction.
The method of shifting the arrangement position of the convex portion 30 is not particularly limited.
Hereinafter, when the six convex portions 30 are distinguished from each other, the convex portions 30i, 30j, 30k, 30m, 30n, and 30p may be referred to.

A convex portion 30i is disposed near the distal end portion of the proximal end side linear portion 26bA of the elastic member 26A.
In the base end side linear portion 26dB of the elastic member 26B adjacent to the base end side linear portion 26bA in the circumferential direction, the convex portion 30j is disposed at a position closer to the base end side than the convex portion 30i.
A convex portion 30k is disposed in the first portion f1 of the bent portion 27fC of the elastic member 26C.
A convex portion 30m is arranged in the second portion h2 of the bent portion 27hA of the elastic member 26A adjacent to the bent portion 27fC in the circumferential direction.
A convex portion 30n is disposed in the third portion h3 of the bent portion 27hC of the elastic member 26C.
A convex portion 30p is disposed between the top portion 26gB and the elastic member fixing portion 38 connected to the elastic member 26C in the distal end side linear portion 26cB of the elastic member 26B.

The arrangement position of each convex part 30 in this embodiment is selected from the range which contacts the inner wall of a blood vessel reliably when placing the electrode support body 100 in the blood vessel. The range of positive contact with the inner wall of the blood vessel may be determined in advance by examining the deformation of the electrode support 100 with respect to the shape of the blood vessel at the indwelling position through experiments or simulations.
The arrangement direction of each convex portion 30 in the present embodiment is a direction in which the end surface 30a faces the distal end side in the direction along the central axis of the elastic members 26A, 26B, and 26C where each is located. For example, in the case of the convex portion 30n, the distal end side in the third portion h3 is the one connected to the distal end side linear portion 26cC.

According to the electrical stimulation electrode 4 of the present embodiment, the electrode support 100 in which the elastic members 26A, 26B, and 26C are assembled is provided as in the first embodiment. For this reason, similarly to the electrical stimulation electrode 1, the electrode support 100 can be placed in a blood vessel such as the superior vena cava P5 for electrical stimulation.
For example, when the electrode support 100 is disposed in a blood vessel such as the superior vena cava P5, the electrode support 100 expands in diameter and presses the inner wall of the blood vessel. In that case, the sliding resistance of the electrode support body 100 increases because each convex part 30 contact | abuts to the inner wall of the blood vessel.
For this reason, according to the electrical stimulation electrode 4, the stimulation electrode portions 10 and 11 can be stably placed even in a flexible and slippery blood vessel.

In the present embodiment, for example, the protrusions 30i, 30j, and 30m have the end surface 30a that faces the distal end side in the axial direction of the electrode support 100 when the electrode support 100 is in a natural state and a reduced diameter (small in FIG. 30). Particularly, the sliding resistance when the electrode support 100 moves forward is increased.
On the other hand, in the natural state of the electrode support 100, the protrusions 30k, 30n, and 30p are directed to the distal end side along the central axis of the elastic member, and obliquely with respect to the axial direction of the electrode support 100. (See the small arrow in FIG. 30). For this reason, the directions of the convex portions 30k, 30n, and 30p are rotated according to the amount of diameter reduction when the electrode support 100 is reduced in diameter, and are closer to the axial direction of the electrode support 100. However, while the convex portions 30i, 30j, and 30m are oriented in the axial direction of the electrode support 100 even when the diameter is reduced, the convex portions 30k, 30n, and 30p are, to some extent, even when the diameter is reduced. The inclination with respect to 100 axial directions remains. For this reason, the protrusions 30k, 30n, and 30p contribute to the sliding resistance in the circumferential direction of the electrode support 100 in addition to the sliding resistance in the axial direction of the electrode support 100.

In the electrical stimulation electrode 4, the convex portion 30 is shifted in the axial direction of the electrode support 100 in the electrode support 100. In particular, in the above example, the positions of the convex portions 30 in the axial direction are all different.
For this reason, when the electrode support 100 is reduced in diameter and the interval between the adjacent elastic members is reduced, the convex portions 30 do not come into contact with each other.
For this reason, it can prevent that the edge part E3 etc. of the convex part 30 mutually contact at the time of diameter reduction, and the convex part 30 deform | transforms or is damaged.
Furthermore, according to the electrical stimulation electrode 4, the outer diameter at the time of diameter reduction of the electrode support body 100 can be reduced compared with the arrangement | positioning which the convex part 30 adjacent to the circumferential direction contact | abuts. Therefore, it is possible to reduce the amount of force required to pull the electrode support 100 into the extraction sheath 60 during extraction.

[Fifth Embodiment]
A medical electrical stimulation electrode according to a fifth embodiment of the present invention will be described.
FIG. 32 is a schematic front view showing the configuration of the main part of the medical electrical stimulation electrode according to the fifth embodiment of the present invention. FIG. 33 is a side view seen from the direction A15 in FIG.

As shown in FIG. 32, the electrical stimulation electrode 5 (medical electrical stimulation electrode) of this embodiment is an electrode instead of the electrode support 25 of the electrical stimulation electrode 1 of the first embodiment. A support 110 is provided. The electrode support 110 can be used in place of the electrode support 25 in the electrical stimulation system 200 of the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

As shown in FIGS. 32 and 33, the electrode support 110 includes six convex portions 30 as in the first embodiment. The electrode support 110 is different from the electrode support 25 only in the arrangement position of the convex part 30.
In the said 1st Embodiment, the arrangement position of the convex part 30 is the same position in the axial direction of the electrode support body 25, and the convex part 30 is adjacent to the other convex part 30 in the circumferential direction. Has been placed. On the other hand, the arrangement position of the convex part 30 in this embodiment is arrange | positioned so that the several convex part 30 which becomes the same position in the axial direction of the electrode support body 110 may not mutually adjoin in the circumferential direction.
Hereinafter, when the six convex portions 30 are distinguished from each other, they may be referred to as convex portions 30q, 30r, 30s, 30t, 30u, and 30v.

A convex portion 30q is disposed in the second portion h2 of the bent portion 27hA of the elastic member 26A.
The convex part 30r is arrange | positioned at the 2nd part h2 of the bending part 27hB of the elastic member 26B.
A convex portion 30s is disposed in the second portion h2 of the bent portion 27hC of the elastic member 26C.
The convex portions 30q, 30r, and 30s are arranged at the same position in the axial direction of the electrode support 110.
On the distal end side linear portion 26cA of the elastic member 26A, a convex portion 30t is disposed between the top portion 26gA and the elastic member fixing portion 38 connected to the elastic member 26B.
A convex portion 30u is disposed between the apex portion 26gB and the elastic member fixing portion 38 connected to the elastic member 26C in the distal end side linear portion 26cB of the elastic member 26B.
A convex portion 30v is disposed between the top portion 26gC and the elastic member fixing portion 38 connected to the elastic member 26A at the distal end side linear portion 26cC of the elastic member 26C.
The convex portions 30t, 30u, and 30v are arranged at the same position in the axial direction of the electrode support 110.

The arrangement position of each convex portion 30 in the present embodiment is selected from a range that reliably contacts the inner wall of the blood vessel when the electrode support 110 is placed in the blood vessel. The range of reliable contact with the inner wall of the blood vessel may be determined in advance by examining the deformation of the electrode support 110 with respect to the shape of the blood vessel at the indwelling position through experiments or simulations.
The arrangement direction of each convex portion 30 in the present embodiment is a direction in which the end surface 30a faces the distal end side in the direction along the central axis of the elastic members 26A, 26B, and 26C where each is located. For example, in the case of the convex portion 30t, the tip side of the tip side linear portion 26cA is the top portion 26gA.

According to the electrical stimulation electrode 5 of the present embodiment, the electrode support 110 is provided in which elastic members 26A, 26B, and 26C are assembled as in the first embodiment. For this reason, the electrode support 110 can be placed in a blood vessel such as the superior vena cava P5, for example, in the same manner as the electrical stimulation electrode 1, and electrical stimulation can be performed.
For example, when the electrode support 110 is disposed in a blood vessel such as the superior vena cava P5, the electrode support 110 expands in diameter and presses the inner wall of the blood vessel. At that time, the sliding resistance of the electrode support 110 increases as each convex portion 30 comes into contact with the inner wall of the blood vessel.
For this reason, according to the electrical stimulation electrode 5, the stimulation electrode portions 10 and 11 can be stably placed even in a flexible and slippery blood vessel.

In the electrical stimulation electrode 5, in the electrode support 110, the convex portions 30 that are at the same position in the axial direction are adjacent to each other with one elastic member interposed therebetween. For this reason, when the electrode support body 110 is reduced in diameter and the interval between the adjacent elastic members is reduced, the convex portions 30 do not come into contact with each other.
For this reason, it can prevent that the edge part E3 etc. of the convex part 30 mutually contact at the time of diameter reduction, and the convex part 30 deform | transforms or is damaged.
Furthermore, according to the electrical stimulation electrode 5, the outer diameter at the time of diameter reduction of the electrode support body 110 can be reduced compared with the arrangement | positioning which the convex part 30 adjacent to the circumferential direction contact | abuts. Therefore, it is possible to reduce the amount of force required to draw the electrode support 110 into the extraction sheath 60 during extraction.

In the description of each of the above embodiments, the example has been described in which the convex portion includes a tapered inclined surface. However, the inclined surface is not limited to a conical tapered surface as long as it is an inclined surface that smoothly inclines from the proximal end side toward the distal end side.
For example, a curved surface in which an axial intermediate portion swells radially outward with respect to a true conical surface may be used. For example, it may be a curved surface in which the axial intermediate portion becomes narrower inward in the radial direction with respect to the true conical surface.
For example, the inclined surface may have an outer shape of a polygonal frustum composed of a combination of planes.

  In the above description of each embodiment, an example in which the electrode support has only the pair of stimulation electrode portions 10 and 11 has been described. However, the number and arrangement positions of such stimulation electrode portions are examples, and are not limited thereto. For example, the stimulation electrode part may be formed on a plurality of bent parts. For example, the stimulation electrode part may be formed on the distal side linear part or the proximal side linear part other than the bent part.

  In the description of each of the above embodiments, an example in which there are six or 18 convex portions on the electrode support has been described. However, the number of convex portions is an example of the number and arrangement position of such stimulation electrode portions, and is not limited thereto. Two or more convex portions can be provided as appropriate.

  In the description of each of the above embodiments, the electrode support fixing member 22 and the engaging portion 53 are described as an example when the four engaging protrusions 22a are engaged with the four engaging grooves 53a. . However, the uneven shape used for engagement is not limited to this. For example, the outer shape of the electrode support fixing member 22 may be formed in a polygonal shape such as a hexagonal shape, and a hexagonal hole that engages with the engaging portion 53 may be provided.

In the description of the second embodiment, the example has been described in which the convex portion 81 includes the protrusions 81X, 81Y, and 81Z.
For example, the convex portion 81 may be configured only by the protrusion 81X. In this case, the length of the projection 81X in the axial direction may be approximately the same as that of the protrusion 30.
Furthermore, a part or all of the protrusions 30 of the first, fourth, and fifth embodiments may be replaced with the protrusions 81X.
For example, the protrusion 81 may have a configuration in which the arrangement interval d2 between the protrusions 81X, 81Y, and 81Z is wider than the axial length d1. In this case, the protrusions 81X, 81Y, and 81Z may be regarded as having three convex portions.

  In the description of the second embodiment, the description has been given of the example in which the plurality of convex portions 81 are arranged separately in specific portions on the elastic member. However, the plurality of convex portions on the elastic member may be determined so that the arrangement number and the arrangement position are constant. The arrangement interval of the plurality of convex portions may be selected from a range of 5 mm to 30 mm, for example.

  In the description of the second embodiment, the example has been described in which the convex portion 81 includes the protrusions 81X, 81Y, and 81Z. However, the number of the protrusions constituting the convex portion 81 may be two or four or more. Good.

In the description of each of the above embodiments, an example in which the cross-sectional shape of the convex portion along the axial direction of the elastic member (hereinafter simply referred to as the cross-sectional shape of the convex portion) is a triangle or a quadrangle has been described. However, the cross-sectional shape of the convex portion is not limited to such a shape.
For example, the cross-sectional shape of the convex portion may be a polygon other than a triangle or a quadrilateral.
For example, the cross-sectional shape of the convex portion is not limited to a shape formed by a combination of straight lines. For example, the cross-sectional shape of the convex portion may be composed of a combination of a straight line and a curve, or only a curve.
For example, the cross-sectional shape of the convex portion may change in the circumferential direction. For example, if the convex portion has an outer peripheral surface that gradually protrudes outward from the elastic member from the proximal end to the distal end with respect to the lead portion, a conical, hemispherical, pyramidal, sawtooth-shaped projection However, the structure arrange | positioned discontinuously in the circumferential direction may be sufficient.

All the components described above can be implemented by being appropriately combined or deleted within the scope of the technical idea of the present invention.
For example, the convex portion 81 in the second embodiment can be used in place of a part or all of the convex portion 30 in the first, fourth, and fifth embodiments.
For example, the convex portion 91 in the third embodiment can be used in place of part or all of the convex portion 30 in the first, fourth, and fifth embodiments.
For example, the convex part 30 in the first embodiment can be used in place of a part or all of the convex part 81 in the second embodiment.
For example, the convex portion 30 in the first embodiment can be used in place of a part or all of the convex portion 91 in the third embodiment.
For example, each protrusion of the convex portion 80 in the second embodiment may be a protrusion having the same shape as the convex portion 91 of the third embodiment.
For example, it is not essential to provide all the convex portions on each elastic member. The electrode support body may have an elastic member without a convex part.
For example, it is not essential to provide the same number of convex portions on each elastic member. The number of convex portions provided on the elastic member of the electrode support may be different.

1, 2, 3, 4, 5 Electrical stimulation electrode (Medical electrical stimulation electrode)
10, 11 Stimulation electrode portion 20 Lead portion 21 Lead body 21A Flexible portion 21B Non-flexible portion 22 Electrode support fixing members 25, 80, 90, 100, 110 Electrode supports 26A, 26B, 26C Elastic members 26bA, 26bB, 26bC, 26dA, 26dB, 26dC Base end side linear portions 26cA, 26cB, 26cC Tip end side linear portions 27fA, 27fB, 27fC, 27hA, 27hB, 27hC Bending portions 30, 30i, 30j, 30k, 30m, 30n, 30p, 30q, 30r, 30s, 30t, 30u, 30v, 81, 91 Convex portions 30a, 81a, 91a End surfaces 30b, 91b Inclined surfaces (outer peripheral surfaces)
34 Coating (Coating material)
34a Outer surface 38 Elastic member fixing portion 40, 41, 42 Overhang portion 50 Operating sheath 51, 61 Sheath body 53 Engaging portion 60 Extraction sheath 70 Electrical stimulation device 81b Inclined surface 81c Side surface (outer peripheral surface)
81X, 81Y, 81Z Protrusion 200 Electrical stimulation system C Axis e3, e4, E3, E6 Edge part f1, h1 First part f2, h2 Second part f3, h3 Third part P Patient P2 Opening P3 Right internal jugular vein (blood vessel) )
P5 superior vena cava (blood vessel)
P6 Vagus nerve (nerve)
V inner wall

Claims (7)

In order to stimulate nerves from the inner wall of a blood vessel, a medical electrical stimulation electrode used by being inserted into the blood vessel,
A stimulation electrode for applying electrical stimulation through the inner wall of the blood vessel;
A linear lead portion that passes through a wiring electrically connected to the stimulation electrode portion;
A linear elastic member is formed into a bowl shape that is substantially rotationally symmetric about a certain axis, and the stimulation electrode portion is provided in a part of the elastic member, and one end portion in the axial direction is an end of the lead portion. An electrode support connected to the section;
Among the outer surface of the elastic member, at least a plurality of convex portions projecting from the outer surface that is the radially outer side of the electrode support,
With
The convex portion is
By have a peripheral surface which gradually protrudes outside of the elastic member toward the distal end from a proximal end to said lead portions, backward toward the proximal end from the distal end to the inner wall Having a sliding resistance that increases in the forward direction from the distal end toward the proximal end,
The electrode support is
A part of the elastic member is bent and includes at least a linear portion that is in a positional relationship obliquely intersecting the axis as viewed from the radial direction, and in the natural state, an outer peripheral portion having the largest outer diameter. Further comprising a plurality of overhang portions arranged in a state of being spaced apart from each other in the circumferential direction;
At least one of the convex portions is
Provided in the overhang ,
Medical electrical stimulation electrode. The outer peripheral surface of the convex portion is
A conical curved surface having an outer diameter gradually increasing from the outer surface of the elastic member from the proximal end toward the distal end;
The convex portion is
Wherein the distal end, wherein the outer surface and the end surface intersecting at an angle of 90 ° or less of said elastic member and said outer peripheral surface is crossed by the edge portion is formed over the entire periphery in the circumferential direction of the elastic member The medical electrical stimulation electrode according to claim 1. The plurality of convex portions are
3. The medical use according to claim 1, wherein the convex portions on the elastic members adjacent to each other in the circumferential direction are located at different positions in the direction along the axis when the electrode support is reduced in diameter. Electrical stimulation electrode. The elastic member is
It has a coating material containing resin on the outer periphery,
The plurality of convex portions are
The medical electrical stimulation electrode according to any one of claims 1 to 3, wherein the medical stimulation electrode is made of the same type of material as the resin. The convex portion is
The medical electrical stimulation electrode according to any one of claims 1 to 4, wherein the medical electrical stimulation electrode is formed on the entire circumference of the outer surface of the elastic member. The convex portion is
The medical electrical stimulation electrode according to any one of claims 1 to 4, wherein the medical electrical stimulation electrode is formed only on an outer surface of the elastic member on a radially outer side of the electrode support. The plurality of convex portions are
The medical electrical stimulation electrode according to any one of claims 1 to 6, further comprising a convex portion provided at a position where the distance from the axis of the electrode support is different from each other.

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