JPWO2015145813A1 - Medical electrical stimulation electrode and medical electrical stimulation device - Google Patents

Abstract

The medical electrical stimulation electrode includes a lead portion, an electrode portion, and a wiring portion. The electrode portion includes a proximal end tip, an elastic wire, and a nerve stimulation electrode. The elastic wire is the proximal end tip. And a proximal bulge portion extending in a direction intersecting the extension line in a plane including an extension line in which the center line of the lead part extends further distally from the distal end of the lead part. The proximal end is connected to the distal end of the proximal bulge, and is inclined with respect to a plane including both the distal end and the extension line of the proximal bulge and approaches in a direction away from the extension line. An inclined portion extending further to the distal side from the distal end of the bulging portion; an intermediate line portion connected to the distal end of the inclined portion; an inclined portion connected to the distal end of the intermediate line portion; A distal bulge extending in a direction crossing the extension line in a plane including both the distal end of the part and the extension line; Eteiru.

Description

The present invention relates to a medical electrical stimulation electrode and a medical electrical stimulation device that apply electrical stimulation to nerve tissue.
This application claims priority based on Japanese Patent Application No. 2014-061233 for which it applied to Japan on March 25, 2014, and uses the content here.

  2. Description of the Related Art Conventionally, stimulation generators that perform treatment by applying electrical stimulation to a living 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 stimulus generators may be used with electrode leads embedded in a living body in order to bring an electrode lead that transmits electrical stimulation into close contact with a stimulus target in the living body.

  In general, an electrode lead applies electrical stimulation to biological tissue, or detects at least one electrode part for detecting electrical excitation generated in the biological tissue, and an electrical connector for electrically connecting to the stimulation generator; A lead body is provided between the electrode unit and the stimulus generator for transmitting electrical stimulation.

  For example, Patent Document 1 discloses a medical electrical lead for stimulating nerves, which minimizes rotation and movement of the lead in the blood vessel, and provides stable and reliable long-term therapy delivery. Techniques that enable it are disclosed.

  The medical electrical lead described in U.S. Patent No. 6,057,017 includes a conductive lead body having a proximal end configured to connect to a pulse generator and at least one configured to deliver an electrical pulse across a vessel wall. A tip portion having an electrode and a lead anchor are provided. The lead anchor disclosed in Patent Document 1 is configured to expand from a folded shape to a previously formed expanded shape. In this lead anchor, when in the folded shape, the tip has an effective length substantially equal to the effective length of the folded lead anchor. The distal end portion of the medical electrical lead described in Patent Document 1 is coupled to the outside of the lead anchor. In Patent Document 1, when the lead anchor is in an expanded shape, the lead anchor presses the lead tip against at least one blood vessel wall of the blood vessel in which the lead is expanded, and the lead tip is deployed and fixed in the blood vessel. The structure to perform is disclosed.

  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.

Japanese National Table 2010-516405

Conventionally, it has been shown that an electrode formed on a lead is urged by a lead anchor to be frictionally engaged in an internal jugular vein in which a vagus nerve coexists.
However, veins are soft and expandable compared to arteries, and the inner surface is smooth and slippery. Even if a mechanism that generates a large urging force is used, deformation such as swelling of the blood vessel occurs and the urging force does not act properly in the normal direction of the blood vessel (blood vessel thickness direction) under the assumption that the urging force acts. It is assumed that stable detention is difficult, such as gradually shifting from the target position. As a result, the relative positional relationship between the electrode and the vagus nerve cannot be maintained, and there is a concern that the nerve stimulation effect may be reduced.

  An object of the present invention is to provide a medical electrical stimulation electrode and a medical electrical stimulation device that can stably place an electrode even in a flexible and slippery vein.

  One aspect of the present invention includes a long lead portion having a distal end and a proximal end, an electrode portion disposed at a distal end of the lead portion, and inserted into the lead portion. A wiring portion connected thereto, and the electrode portion includes a proximal end tip fixed to a distal end of the lead portion, a first end fixed to the proximal end tip, and a distal end from the first end. An elastic wire having a second end located on the distal side, and a nerve stimulation electrode fixed to the elastic wire, the elastic wire being fixed to the proximal end tip and the center of the lead portion A proximal bulge extending in a direction intersecting the extension line in a plane including an extension line extending further from the distal end of the lead portion to the distal side; and a distance from the proximal bulge portion A proximal end connected to the distal end and inclined with respect to a plane including both the distal end of the proximal bulge and the extension line And an inclined portion extending further distally from the distal end of the proximal bulge portion in a direction away from the extension line; and a distal end of the inclined portion connected to the distal end of the inclined portion; And a distal bulge extending in a direction intersecting the extension line in a plane including both extension lines.

  According to the second aspect of the present invention, in the medical electrostimulation electrode according to the first aspect, the inclined part has the maximum bulging part where the distance between the elastic wire and the extension line is maximized. It may be arcuate to have between the distal and proximal ends of the part.

  According to a third aspect of the present invention, in the medical electrical stimulation electrode according to the second aspect, the distal end and the proximal end of the inclined portion may be equidistant from the extension line.

  According to a fourth aspect of the present invention, in the medical electrical stimulation electrode according to the third aspect, the nerve stimulation electrode has an outer periphery of the inclined portion in a region including the maximum bulging portion of the inclined portion. The surface may be exposed to a surface opposite to the surface facing the extension line and fixed to the inclined portion, and the wiring portion may be connected to the nerve stimulation electrode through the elastic wire. .

  According to a fifth aspect of the present invention, in the medical electrical stimulation electrode according to the fourth aspect, the elastic wire has a proximal end connected to a distal end of the inclined portion, and the elastic wire and the extension The inclined portion has an arc shape so as to have a second maximum bulge portion having a maximum distance to the line between the distal end and the proximal end of the inclined portion, and the inclined portion when viewed from the direction in which the extension line extends. A second inclined portion extending so as to substantially overlap the distal end and connected to a proximal end of the distal bulge portion, and the nerve stimulation electrode includes the maximum bulge portion of the inclined portions In the region, a first electrode exposed to a surface opposite to a surface directed to the extension line of the outer peripheral surface of the inclined portion and fixed to the inclined portion, and the second of the second inclined portions In the region including the maximum bulge portion, the outer surface of the second inclined portion is opposite to the surface directed to the extension line. A second electrode exposed to the second inclined portion and fixed to the second inclined portion, the wiring portion passing through the inside of the elastic wire and connected to the first electrode; and the inside of the elastic wire A second wire connected to the second electrode through the distal bulge portion, and the distal bulge portion may be connected to the inclined portion via the second inclined portion.

  According to a sixth aspect of the present invention, in the medical electrical stimulation electrode according to the fifth aspect, the electrode portion is a wire different from the elastic wire and does not include the nerve stimulation electrode, and the extension line A symmetrical elastic wire having a plane-symmetrical shape with a plane passing between the elastic wire and a plane passing through the elastic wire, and the electrode portion has one elastic wire and the same shape and size as the elastic wire. And one or more of the same type elastic wires that do not include the nerve stimulation electrode, and the same number of the symmetrical elastic wires as the sum of the numbers of the elastic wires and the same type of elastic wires.

  According to a seventh aspect of the present invention, in the medical electrical stimulation electrode according to the fifth or sixth aspect, the elastic wire includes a distal end of the inclined portion and a proximal end of the second inclined portion. And the intermediate line portion whose distance to the extension line is shorter than the distance from the extension line of each of the maximum bulge portion and the second maximum bulge portion.

  According to an eighth aspect of the present invention, a medical electrical stimulation device generates a predetermined electrical stimulation pulse that is connected to the medical electrical stimulation electrode of each of the above aspects and that is connected to the wiring unit and stimulates the vagus nerve. A pulse generator for outputting to the electrode unit, and the electrode unit is formed to have a bowl shape larger than the inner diameter of the superior vena cava when no external force is applied, the elastic wire, and the elastic In addition to the wire, it has another wire that defines the shape of the bowl, and the elastic wire and the other wire are deformed in a convex shape toward the inside of the blood vessel when the superior vena cava is pressed by the trachea In this area, the elastic wire is elastically deformed so that the convex portion is located between the elastic wire and the other wire, and can be placed in the superior vena cava.

  According to each aspect described above, the position of the electrode is stable even in a flexible and slippery vein.

1 is an overall view showing a medical electrical stimulation device including a medical electrical stimulation electrode according to a first embodiment of the present invention. It is sectional drawing which shows the medical electrical stimulation electrode which concerns on 1st Embodiment of this invention. It is sectional drawing in the III-III line of FIG. It is sectional drawing in the IV-IV line of FIG. It is sectional drawing in the VV line of FIG. It is a figure which shows the 1st elastic wire in the medical electrical stimulation electrode which concerns on 1st Embodiment of this invention. It is the figure seen from the arrow VII direction of FIG. It is the figure seen from the arrow VIII direction of FIG. It is the figure seen from the arrow IX direction of FIG. It is sectional drawing which shows the nerve stimulation electrode provided in the 1st elastic wire of 1st Embodiment of this invention. It is sectional drawing which shows the nerve stimulation electrode provided in the 1st elastic wire of 1st Embodiment of this invention. It is a figure for demonstrating the effect | action of the medical electrical stimulation electrode and medical electrical stimulation apparatus which concern on 1st Embodiment of this invention. It is a figure for demonstrating the effect | action of the medical electrical stimulation electrode and medical electrical stimulation apparatus which concern on 1st Embodiment of this invention. It is sectional drawing in the XIV-XIV line | wire of FIG. It is a figure which shows the modification of the medical electrical stimulation electrode which concerns on 1st Embodiment of this invention, and is sectional drawing in the site | part similar to the VV line of FIG. It is a figure which shows the 2nd modification of the medical electrical stimulation electrode which concerns on 1st Embodiment of this invention, and is a figure which shows one process at the time of use of the medical electrical stimulation electrode of a 2nd modification. It is sectional drawing in the XVII-XVII line of FIG. It is a figure which shows a part of medical electrical stimulation electrode which concerns on 2nd Embodiment of this invention, and is sectional drawing in the site | part similar to the VV line of FIG. It is a figure for demonstrating the structure of the inclination part in the medical electrical stimulation electrode which concerns on 2nd Embodiment of this invention. It is the figure seen from the arrow XX direction of FIG. It is the figure seen from the arrow XXI direction of FIG. It is a perspective view which shows the electrode part in the medical electrical stimulation electrode which concerns on 3rd Embodiment of this invention. It is the figure seen from the arrow XXII direction of FIG.

[First Embodiment]
A medical electrical stimulation electrode according to a first embodiment of the present invention and a medical electrical stimulation device including the same will be described. FIG. 1 is an overall view showing a medical electrical stimulation apparatus including a medical electrical stimulation electrode according to the present embodiment. FIG. 2 is a cross-sectional view showing the medical electrical stimulation electrode according to the present embodiment. 3 is a cross-sectional view taken along line III-III in FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. FIG. 5 is a cross-sectional view taken along line VV in FIG. FIG. 6 is a view showing a first elastic wire in the medical electrical stimulation electrode according to the present embodiment. FIG. 7 is a view as seen from the direction of arrow VII in FIG. FIG. 8 is a view seen from the direction of arrow VIII in FIG. FIG. 9 is a view seen from the direction of the arrow IX in FIG. FIG. 10 is a cross-sectional view showing the nerve stimulation electrode provided on the first elastic wire of the present embodiment. FIG. 11 is a cross-sectional view showing the nerve stimulation electrode provided on the first elastic wire of the present embodiment.

  The medical electrical stimulation device according to the present embodiment is a device that performs treatment by applying electrical stimulation to a nerve of a patient. As an example, in the present embodiment, an apparatus for applying electrical stimulation to a patient's vagus nerve is shown.

  As shown in FIG. 1, a medical electrical stimulation device 1 applies electrical stimulation to a placement site in a blood vessel via a medical electrical stimulation electrode 2 placed in the blood vessel and the medical electrical stimulation electrode 2. A pulse generator 60.

  The medical electrical stimulation electrode 2 includes a lead portion 3, an electrode portion 15, and a sheath portion 52.

The lead portion 3 shown in FIGS. 1 and 2 is a flexible long member for guiding the electrode portion 15 to a predetermined indwelling position. In the present embodiment, the side on which the electrode portion 15 is disposed among the both ends of the lead portion 3 is the distal end of the lead portion 3. Of the both ends of the lead portion 3, the end opposite to the end on which the electrode portion 15 is disposed is the proximal end. Hereinafter, in the present specification, the distal side and the proximal side of the medical electrical stimulation electrode 2 are shown based on the distal end and the proximal end of the lead portion 3.
The lead portion 3 includes a lead body 4, a connector 9 and an adapter 11 disposed at the proximal end of the lead body 4.

As shown in FIG. 2, the lead body 4 is a flexible long member. The distal portion of the lead body 4 is disposed in the blood vessel when the medical electrical stimulation electrode 2 is used. The proximal portion of the lead body 4 is disposed outside the body when the medical electrical stimulation electrode 2 is used.
The lead body 4 includes a pipe line part 5 and a wiring part 12.

  The duct part 5 is inserted into the blood vessel from the vicinity of the left and right necks or the vicinity of the left and right clavicles on the surface of the living body and attached to the patient. A part of the proximal portion of the duct portion 5 is exposed outside the patient's body. The conduit portion 5 includes a lead tube 6 and a liquid feeding tube 8. The lead tube 6 is made of polyurethane having an outer diameter of φ1 to 3 mm and a total length of about 500 mm, for example. The liquid feeding tube 8 is inserted into the lead tube 6.

  As shown in FIGS. 1 and 2, the lead tube 6 has a branch block 7 in a portion located outside the body when attached to a patient.

As shown in FIG. 1, the branch block 7 has a through hole 7a and a branch hole 7b. The through hole 7 a communicates with the proximal end of the lead tube 6. The branch hole 7 b is branched from the through hole 7 a and guides the liquid feeding tube 8. A connection cable 10 for connecting the medical electrical stimulation electrode 2 to the pulse generator 60 is attached to the through hole 7 a of the branch block 7. A wiring portion 12 is inserted through the connection cable 10.
In the branch block 7, the pipe line part 5 is branched into a liquid feeding tube 8 and a connection cable 10. The connection cable 10 can be connected to the pulse generator 60.

  The liquid feeding tube 8 has a connector 9 with a luer lock that can be connected to a syringe at the proximal end.

  An adapter 11 for connecting the connection cable 10 to the pulse generator 60 is disposed at the proximal end of the connection cable 10.

As shown in FIG. 2, the wiring part 12 is inserted into the lead part 3 and connected to the electrode part 15. The wiring unit 12 can be connected to the pulse generator 60 shown in FIG.
The wiring unit 12 includes a first wiring 13 and a second wiring 14.

  For the first wiring 13 and the second wiring 14, a wire material in which a stranded wire made of a nickel cobalt alloy (35 NLT 25% Ag material) having bending resistance is covered with an electrical insulating material (ETFE having a thickness of 20 μm) is used. .

  As shown in FIGS. 2, 10, and 11, the distal end of the first wiring 13 is connected to the first electrode 43 through the inside of a first elastic wire 27 described later. The distal end of the second wiring 14 is connected to the second electrode 45 through the inside of the first elastic wire 27.

The conduit portion 5 shown in FIG. 2 can be used to introduce a predetermined drug solution into the blood vessel in a state where the medical electrical stimulation electrode 2 is placed in the blood vessel. The pipe line part 5 is a flexible cylindrical member, for example, a resin tube.
The distal end of the duct portion 5 communicates with a proximal opening 19 in a proximal end tip 16 described later. The proximal end of the pipe line part 5 is connected to the branch block 7.

As shown in FIG. 1, the electrode portion 15 is disposed at the distal end of the lead portion 3. When the electrode unit 15 is used, the electrode unit 15 is placed at a position close to the tissue (the vagus nerve 100 in the present embodiment) to which electrical stimulation is applied.
The electrode portion 15 includes a proximal end tip 16, an elastic wire portion 26, a distal end tip 41, and a nerve stimulation electrode 42.

As shown in FIGS. 1 and 2, the proximal end tip 16 is fixed to the distal end of the lead portion 3. Specifically, the proximal end tip 16 is fixed to each of the distal end of the lead tube 6 and the distal end of the liquid feeding tube 8.
As shown in FIG. 2, the proximal end chip 16 includes a chip body 17, a lead connection part 23, a wire connection part 24, and a polygonal column part 25.

A proximal end of each elastic wire (27, 47, 48, 49, 50, 51), which will be described later, constituting the elastic wire portion 26 is fixed to the chip body 17. Each elastic wire (27, 47, 48, 49, 50, 51) and the chip body 17 are fixed by welding, adhesion, or caulking.
In the present embodiment, the chip body 17 is made of metal. For example, the chip body 17 is made of titanium. The chip body 17 may be made of resin. The outer surface of the chip body 17 has a structure that can prevent the occurrence of blood clots that cause blood clots. As an example, the outer surface of the chip body 17 may have a structure for suppressing blood coagulation. For example, the outer surface of the chip body 17 may be coated with a drug that suppresses coagulation of blood, or may have a surface shape for preventing blood retention.

A liquid discharge pipe 18 and a wiring insertion path 22 are formed inside the chip body 17.
The liquid discharge pipe 18 functions as a discharge pipe that discharges a predetermined chemical solution such as an antithrombotic agent. The liquid discharge conduit 18 includes a proximal opening 19, a distal opening 20, and a flow path 21.

The proximal opening 19 communicates with the distal end of the conduit portion 5 of the lead body 4.
The distal opening 20 is opened at the distal end surface of the chip body 17.
The flow path portion 21 extends along a straight line connecting the distal end and the proximal end of the chip body 17.

  The wiring insertion path 22 is a conduit through which the first wiring 13 and the second wiring 14 of the wiring portion 12 are inserted. The wiring insertion path 22 guides the first wiring 13 and the second wiring 14 to the first elastic wire 27. In the present embodiment, the wiring insertion path 22 is configured as a gap portion generated between the inner peripheral surface of the lead tube 6 and the outer peripheral surface of the liquid feeding tube 8.

  The lead connection portion 23 is a portion to which the distal end of the lead body 4 is fixed. In the present embodiment, the lead connection portion 23 connects the distal end of the duct portion 5 and the distal end of the wiring portion 12 in the lead body 4 to the chip body 17.

  The wire connection portion 24 is elastic so that each elastic wire (27, 47, 48, 49, 50, 51) extends in a direction intersecting with a straight line connecting the distal end and the proximal end of the chip body 17. The proximal end of the wire (27, 47, 48, 49, 50, 51) and the chip body 17 are connected.

  As shown in FIG. 3, the polygonal column portion 25 is an engaged portion with which a polygon hole portion 57 (see FIGS. 2 and 4) to be described later engages. In the present embodiment, the polygonal column portion 25 is a hexagonal column.

  As shown in FIGS. 1 and 5, the elastic wire portion 26 includes a first elastic wire 27, a second elastic wire 47, a third elastic wire 48, a fourth elastic wire 49, and a fifth elastic wire 50. The sixth elastic wire 51 is provided. The elastic wire spreads at substantially equal intervals around the extension line of the center line of the lead portion 3 so that the electrode portion 15 forms a basket shape (saddle shape) as a whole. In the present embodiment, the elastic wire portion 26 has a spherical shape as a whole in a state where no external force is applied to the elastic wire portion 26. When the elastic wire portion 26 is spherical, the diameter of the elastic wire portion 26 depends on the shape of the tissue to which the electrode portion 15 is to be placed, and the tissue at the placement site is each elastic wire (27, 47, 48, 49, 50, 51) is set to a size that can be pressed.

  An extension line C (see FIGS. 2 and 5) of the center line of the lead portion 3 is a central axis line in the basket shape of the elastic wire portion 26. In the present specification, the extension line direction of the center line of the lead part 3 is described as the axial direction of the elastic wire part 26, and the direction orthogonal to the extension line of the center line of the lead part 3 is described as the radial direction of the elastic wire part 26.

  In the present embodiment, the first elastic wire 27, the third elastic wire 48, and the fifth elastic wire 50 have the same shape and the same size, and the second elastic wire 47, the fourth elastic wire 49, and the sixth elastic wire. The wires 51 have the same shape and the same size. In the present embodiment, the first elastic wire 27 has a first end 27a and a second end 27b located on the distal side of the first end 27a. The first end 27 a is fixed to the proximal end tip 16. The first elastic wire 27 has the nerve stimulation electrode 42, and the other elastic wires do not have the nerve stimulation electrode 42.

  Below, the structure of the 1st elastic wire 27 and the structure of the 2nd elastic wire 47 are explained in full detail, and the description which overlaps with the 1st elastic wire 27 or the 2nd elastic wire 47 is abbreviate | omitted about another elastic wire. In the drawing, among the constituent elements of the third elastic wire 48, the fourth elastic wire 49, the fifth elastic wire 50, and the sixth elastic wire 51, the same as the first elastic wire 27 and the second elastic wire 47. Constituent elements are given the same reference numerals as those attached to the first elastic wire 27 or the second elastic wire 47.

The first elastic wire 27 shown in FIGS. 5, 6, and 7 is generally a semicircle having a radius larger than the radius of the blood vessel on which the electrode portion 15 of the medical electrical stimulation electrode 2 is placed. It is formed in an arc shape. In the blood vessel, the first elastic wire 27 is pressed and elastically deformed by the inner wall of the blood vessel, and a part of the first elastic wire 27 comes into close contact with the inner wall of the blood vessel by the restoring force.
The first elastic wire 27 is made of, for example, a shape memory alloy. The cross-sectional shape orthogonal to the center line of the first elastic wire 27 is a circular cross section with a diameter of 0.2 to 0.4 mm or a rectangular cross section with a side of 0.2 to 0.4 mm. The radius of the first elastic wire 27 in a state where the first elastic wire 27 is formed in a semicircular arc shape is 10 to 20 mm. In the present embodiment, the outer peripheral surface of the first elastic wire 27 is coated with a polyurethane resin coating or a polyamide resin coating having a thickness of 50 to 500 μm, which makes it difficult to generate thrombus.

  As shown in FIGS. 6 and 7, the first elastic wire 27 includes a proximal bulging portion 28, a first inclined portion 29, an intermediate line portion 34, a second inclined portion 35, and a distal bulging portion. 40. In addition, the first elastic wire 27 has an insulating coating on the outer peripheral surface thereof except for a first opening 33 and a second opening 39 (see FIG. 9) described later. The insulating coating of the first elastic wire 27 may be formed by being melt-bonded to the outer surface of the first elastic wire 27 by, for example, a heat shrinkable tube.

The proximal bulge portion 28 extends in a direction crossing the extension line C in a plane where an extension line C is formed in which the center line of the lead portion 3 extends further distally from the distal end of the lead portion 3. .
The proximal end of the proximal bulge portion 28 is a first end fixed to the distal end face of the proximal end tip 16.

The first inclined portion 29 is provided in the vicinity of the apex of the semicircular arc shape of the first elastic wire 27, that is, in the vicinity of the portion farthest from the extension line of the center line of the lead portion 3. The first inclined portion 29 is disposed at a position where the first inclined wire 29 is relatively strongly pressed against the inner wall of the blood vessel in the entire length of the first elastic wire 27. The first inclined portion 29 has a proximal end connected to the distal end of the proximal bulge portion 28. Further, the first inclined portion 29 is inclined with respect to a plane where both the distal end of the proximal bulge portion 28 and the central axis (extension line) of the elastic wire portion 26 exist, and from the central axis of the elastic wire portion 26. It extends from the distal end of the proximal bulge 28 further to the distal side in the direction of leaving.
The first inclined portion 29 extends from the distal end of the proximal bulging portion 28 obliquely about 3 to 8 mm in the circumferential direction of the elastic wire portion 26 and in the axial direction of the elastic wire.
A first maximum bulging portion 30 is formed between the distal end and the proximal end of the first inclined portion 29.
Further, the distal end and the proximal end of the first inclined portion 29 are equidistant from the central axis of the elastic wire portion 26.

The first largest bulging portion 30 is an apex portion of an arc that bulges about 1 to 3 mm from the proximal end and the distal end of the first inclined portion 29 in the radial direction of the elastic wire portion 26. That is, the first maximum bulging portion 30 is a portion where the distance between the first elastic wire 27 and the central axis of the elastic wire portion 26 is maximum.
A first electrode exposed portion 31 is provided on a part of the first inclined portion 29 including the first maximum bulging portion 30.

  The first electrode exposed portion 31 shown in FIG. 9 includes a first covering portion 32 and a first opening portion 33. The first covering portion 32 is formed with a polyurethane resin coating or a polyamide resin coating so as to cover the first electrode 43. The first opening 33 defines an electrical stimulation electrode region that contacts the inner wall of the blood vessel. The first opening 33 is formed by removing the resin coating constituting the first covering portion 32 so that the outer surface of the first electrode 43 is exposed in a rectangular shape of 0.5 mm × 3.8 mm, for example. The first opening 33 is disposed on the surface of the outer peripheral surface of the first elastic wire 27 opposite to the surface directed toward the central axis of the elastic wire portion 26.

The intermediate line portion 34 connects the first inclined portion 29 and the second inclined portion 35. The length of the intermediate line portion 34 defines the distance between the first inclined portion 29 and the second inclined portion 35. The first electrode 43 is disposed on the first inclined portion 29. The second electrode 45 is disposed on the second inclined portion 35. The first electrode 43 and the second electrode 45 will be described later. The distance between the first electrode 43 and the second electrode 45 is set to a suitable distance with respect to the tissue to be stimulated mainly by the length of the intermediate line portion 34.
The intermediate line portion 34 is arranged at a position protruding in the circumferential direction of the elastic wire portion 26 with respect to the proximal bulge portion 28 and the distal bulge portion 40 when viewed from the central axis direction of the elastic wire portion 26. Has been. The intermediate line portion 34 connects the distal end of the first inclined portion 29 and the proximal end of the second inclined portion 35 in a straight line. The distance between the central axis of the elastic wire part 26 and the intermediate line part 34 is shorter than the distance between the central axis of the elastic wire part 26 and the first largest bulge part 30, and the distance between the central axis of the elastic wire part 26 and It is shorter than the distance between the second maximum bulging portion 36 described later.

As shown in FIGS. 7 and 9, the second inclined portion 35 is in the vicinity of the apex of the semicircular arc shape of the first elastic wire 27, that is, in the vicinity of the portion farthest from the extension line of the center line of the lead portion 3. Is provided. The second inclined portion 35 is disposed at a position where the second inclined portion 35 is relatively strongly pressed against the inner wall of the blood vessel in the entire length of the first elastic wire 27.
The second inclined portion 35 extends from the proximal end of the distal bulge portion 40 obliquely about 3 to 8 mm in the circumferential direction of the elastic wire portion 26 and in the axial direction of the elastic wire.
The proximal end of the second inclined portion 35 is connected to the distal end of the first inclined portion 29 via an intermediate line portion 34. The second inclined portion 35 has a second maximum bulging portion 36 between the distal end and the proximal end of the second inclined portion 35 and has an arc shape. In the second maximum bulging portion 36, the distance between the first elastic wire 27 and the central axis of the elastic wire portion 26 is the maximum. Further, the distal end and the proximal end of the second inclined portion 35 are equidistant from the central axis of the elastic wire portion 26.
When viewed from the central axis direction of the elastic wire portion 26, the second inclined portion 35 extends so as to substantially overlap the first inclined portion 29.
The distal end of the second inclined portion 35 is connected to the proximal end of the distal bulge portion 40.

The second maximum bulging portion 36 is an apex portion of an arc that bulges about 1 to 3 mm from the proximal end and the distal end of the second inclined portion 35 in the radial direction of the elastic wire portion 26. That is, the second maximum bulge portion 36 is a portion where the distance between the first elastic wire 27 and the central axis of the elastic wire portion 26 is the maximum.
In the present embodiment, the first maximum bulge portion 30 and the second maximum bulge portion 36 have the same distance from the central axis of the elastic wire portion 26.
A second electrode exposed portion 37 is provided in a part of the second inclined portion 35 including the second maximum bulging portion 36.

  The second electrode exposed portion 37 shown in FIG. 9 is separated from the first electrode exposed portion 31 by about 3 to 8 mm at the shortest distance. The second electrode exposed portion 37 includes a second covering portion 38 and a second opening 39. The second covering portion 38 is formed with a polyurethane resin coating or a polyamide resin coating so as to cover the second electrode 45. The second opening 39 defines an electrical stimulation electrode region that contacts the inner wall of the blood vessel. The second opening 39 is formed by removing the resin coating constituting the second coating portion 38 so that, for example, the outer surface of the second electrode 45 is exposed in a rectangular shape of 0.5 mm × 3.8 mm. The second opening 39 is disposed on the surface of the outer peripheral surface of the first elastic wire 27 opposite to the surface directed toward the central axis of the elastic wire portion 26.

As shown in FIGS. 6 and 7, the distal bulge portion 40 is connected to the distal end of the first inclined portion 29 via the intermediate line portion 34 and the second inclined portion 35 in this embodiment. ing. The distal bulge portion 40 extends in a direction intersecting the central axis of the elastic wire portion 26 in a plane where both the distal end of the first inclined portion 29 and the central axis (extension line C) of the elastic wire portion 26 exist. Yes.
The distal end of the distal bulge portion 40 is positioned on the first elastic wire 27 more distally than the first end and is fixed to the distal end tip 41 (see FIG. 1). It has become.

  The distal end tip 41 shown in FIG. 1 has a hemispherical distal end side and a cylindrical shape on the proximal side. The distal end of each elastic wire (27, 47, 48, 49, 50, 51) constituting the elastic wire portion 26 is fixed to the near end surface of the distal end tip 41. In the present embodiment, the distal end tip 41 is made of metal. For example, the distal end tip 41 is made of titanium. Each elastic wire (27, 47, 48, 49, 50, 51) and the distal end tip 41 are fixed by welding, adhesion, or caulking.

Next, the configuration of the nerve stimulation electrode 42 will be described.
As shown in FIGS. 9, 10, and 11, the nerve stimulation electrode 42 is fixed to the first elastic wire 27. The nerve stimulation electrode 42 includes a platinum positive-side electrical stimulation electrode (hereinafter referred to as “first electrode 43”) disposed on the first inclined portion 29 and a platinum minus disposed on the second inclined portion 35. Side electrical stimulation electrode (hereinafter referred to as “second electrode 45”).

  The first electrode 43 is made of a platinum iridium alloy having a cylindrical shape of φ0.8 mm and a length of 4 mm. The first electrode 43 is welded to the first wiring 13. The first electrode 43 has an insulating first resin coating 44 for preventing a short circuit with the first elastic wire 27. The first resin coating 44 of the first electrode 43 is opened at the first opening 33.

  The second electrode 45 is separated from the first electrode 43 by a shortest distance of about 3 to 8 mm. The second electrode 45 is made of a platinum iridium alloy having a cylindrical shape of φ0.8 mm and a length of 4 mm. The second electrode 45 is welded to the second wiring 14. The second electrode 45 has an insulating second resin coating 46 for preventing a short circuit with the first elastic wire 27. The second resin coating 46 of the first electrode 43 is opened at the second opening 39.

Next, the configuration of another elastic wire in the elastic wire portion 26 will be described.
As shown in FIG. 5, the second elastic wire 47 is a symmetrical elastic wire that is symmetrical with respect to the first elastic wire 27. That is, the first elastic wire 27 and the second elastic wire 47 that constitute the elastic wire portion 26 and are adjacent to each other face each other so that the respective inclined portions (the first inclined portion 29 and the second inclined portion 35) are close to each other. Have a different shape. In other words, the first elastic wire 27 and the second elastic wire 47 have a plane S passing through the middle between the first elastic wire 27 and the second elastic wire 47 with the central axis (extension line C) of the elastic wire portion 26 existing. It has a plane-symmetric shape with the plane of symmetry (see FIG. 5) as the plane of symmetry.
The angle formed between the first elastic wire 27 and the second elastic wire 47 when viewed from the direction of the central axis of the elastic wire portion 26 is set to 60 °.

  The third elastic wire 48 and the fifth elastic wire 50 are the same type elastic wires having the same diameter and the same shape and the same size as the first elastic wire 27, but without the first electrode 43 and the second electrode 45. The difference is that the part 12 is not arranged either.

  The fourth elastic wire 49 and the sixth elastic wire 51 have the same diameter and the same size as the second elastic wire 47, and are symmetrical elastic wires with respect to the first elastic wire 27.

In the present embodiment, a total of three wires including the first elastic wire 27 and having the same diameter and the same size as the first elastic wire 27 and a wire having the same diameter and the same size as the second elastic wire 47 are the first. There are a total of three including the two elastic wires 47.
For this reason, in this embodiment, in each elastic wire (27, 47, 48, 49, 50, 51), the protruding direction of the intermediate line portion 34 in the circumferential direction of the elastic wire portion 26 is the central axis direction of the elastic wire portion 26. There are three clockwise protrusions and three counterclockwise protrusions when viewed from the distal end side. Thus, in each elastic wire (27, 47, 48, 49, 50, 51), the protruding direction of the intermediate line portion 34 in the circumferential direction of the elastic wire portion 26 is the same in the clockwise direction and the counterclockwise direction. Yes. As a result, when the elastic wire portion 26 is rotated around the blood vessel axis in the blood vessel, the feel transmitted to the operator who performs the rotation operation is the same in the clockwise direction and the counterclockwise direction.

  In the present embodiment, the first elastic wire 27, the second elastic wire 47, the third elastic wire 48, the fourth elastic wire 49, the fifth elastic wire 50, and the sixth elastic wire 51 are the central axis of the elastic wire portion 26. As viewed from the direction, the elastic wire portions 26 are arranged at regular intervals (every 60 °) with the central axis of the elastic wire portion 26 as the center.

  As shown in FIGS. 1 and 2, the sheath portion 52 includes a flexible tube portion 53, an operation portion 56, and a polygonal hole portion 57. The flexible tube 53 has the lead tube 6 inserted therein. The operation portion 56 is disposed at the proximal end of the flexible tube portion 53. The polygonal hole portion 57 is disposed at the distal end of the flexible tube portion 53.

The flexible tube portion 53 is a tube with a blade made of polyurethane or polyamide with a built-in stainless steel net assembly. In the present embodiment, the outer diameter of the flexible tube portion 53 is about φ2.8 mm, the inner diameter of the flexible tube portion 53 is about φ2 mm, and the length of the flexible tube portion 53 is about 300 mm.
An O-ring 54 and a liquid feeding branch tube 55 are provided at the proximal end of the flexible tube portion 53. The O-ring 54 can contact the outer peripheral surface of the lead tube 6 so as to close the gap with the lead tube 6 in a watertight manner. The liquid feeding branch tube 55 communicates with the inside of the flexible tube portion 53 on the distal side of the O-ring 54.
The liquid feeding branch tube 55 can be used as a conduit for flowing a liquid such as a contrast medium for confirming the travel of the blood vessel. A luer lock type syringe or the like can be watertightly connected to the end of the liquid feeding branch tube 55 opposite to the end communicating with the inside of the flexible tube portion 53.

  The operation unit 56 is a part where an operation for adjusting the position of the electrode unit 15 using the sheath unit 52 is performed by the operator.

  As shown in FIGS. 2 and 4, the polygonal hole portion 57 is formed with a hole that follows the outer shape (see FIG. 3) of the polygonal column portion 25 of the proximal end tip 16 and engages with the polygonal column portion 25. The polygonal hole 57 is made of metal, for example, titanium in this embodiment. The polygonal hole portion 57 is bonded to the distal end surface of the flexible tube portion 53. The polygonal hole 57 has a hexagonal cross section. The polygonal hole portion 57 can be suitably engaged with the polygonal column portion 25 having a hexagonal column shape in the present embodiment.

The pulse generator 60 shown in FIG. 1 generates a constant current type or constant voltage type biphasic waveform group with a predetermined interval. For example, a biphasic waveform with a frequency of 20 Hz and a pulse width of 50 to 400 μsec and a plus to minus a few volts is generated by the pulse generator 60 for 3 to 20 seconds per minute.
The configuration of the pulse generator 60 is not particularly limited, and a configuration that can be connected to the medical electrical stimulation electrode 2 may be appropriately selected and employed.

  Next, the operation of the medical electrical stimulation device 1 according to this embodiment will be described. FIG. 12 is a diagram for explaining the operation of the medical electrical stimulation electrode and the medical electrical stimulation device according to the present embodiment. FIG. 13 is a diagram for explaining the operation of the medical electrical stimulation electrode and the medical electrical stimulation device. 14 is a cross-sectional view taken along line XIV-XIV in FIG.

When the medical electrical stimulation device 1 according to this embodiment is used, the electrode portion 15 of the medical electrical stimulation electrode 2 is placed in the blood vessel, and the lead portion 3 is drawn out of the body. In addition, when the medical electrical stimulation device 1 according to this embodiment is used, a syringe piston pump (not shown) and a pulse generator 60 that generates electrical stimulation are installed outside the body. The syringe piston pump is used to continuously administer heparin, a drug that prevents thrombus.
The syringe piston pump is connected to the connector 9 of the lead portion 3 shown in FIG. 1 and can supply heparin to a flow path extending from the connector 9 to the distal opening 20 of the chip body 17 through the conduit portion 5.

  By using an introducer or dilator at the living body insertion port, it is possible to easily puncture a blood vessel existing under the skin. For this reason, the medical electrical stimulation electrode 2 can be inserted into the blood vessel with minimal invasiveness.

  The medical electrical stimulation electrode 2 is roughly installed at a predetermined position of the superior vena cava 102 shown in FIG. Thereafter, while generating electrical stimulation from the pulse generator 60 shown in FIG. 1, the medical electrical stimulation electrode 2 is operated from outside the body to adjust the position of the electrode unit 15 in the blood vessel axis direction and the rotation direction around the blood vessel axis. The position of the electrode part 15 in the rotation direction around the blood vessel axis can be adjusted by rotating the sheath part 52 around the axis line with the polygonal hole part 57 engaged with the polygonal column part 25.

  By monitoring the heart rate obtained by an electrocardiograph or the like, the most significant decrease in heart rate can be confirmed when the first electrode 43 and the second electrode 45 are positioned toward the vagus nerve 100. The optimal stimulation position is the position where the decrease in heart rate is significant. In this embodiment, a suitable position where the electrode portion 15 is placed is a portion where the vagus nerve 100 reaching the heart on the back side of the superior vena cava 102 is running along with the superior vena cava 102 as shown in FIG. It is.

  The first electrode 43 and the second electrode 45 are radially outward of the blood vessel by the biasing force of the first elastic wire 27 made of shape memory alloy and the biasing forces of the other five elastic wires other than the first elastic wire 27. It is pressed against. Further, the first electrode 43 and the second electrode 45 are respectively disposed on the first maximum bulge portion 30 in the first inclined portion 29 and the second maximum bulge portion 36 in the second inclined portion 35. For this reason, the first electrode 43 and the second electrode 45 are in close contact with each other along the inner peripheral surface of the blood vessel. When the first electrode 43 and the second electrode 45 are in close contact with the inner wall surface of the blood vessel, leakage of electrical energy to the blood side is reduced, and stimulation of the vagus nerve 100 is performed efficiently.

  As shown in FIG. 14, the blood vessel shape of the superior vena cava 102 is not a circular cross-sectional shape due to the trachea 103 on the back side of the superior vena cava 102, but has a flat cross-sectional shape in the direction of the trachea 103. When the electrode portion 15 of the medical electrical stimulation electrode 2 according to the present embodiment is placed in the superior vena cava 102, a guide sheath is used so that the electrode is placed facing the vagus nerve 100 on the back side, Adjust the position of the electrode.

  At this time, the vascular wall located on the trachea 103 side of the superior vena cava 102 has a bulge that protrudes toward the inside of the blood vessel due to the influence of the trachea 103, and each elastic wire (27, 47 , 48, 49, 50, 51) try to fit so as to avoid the convex part due to its bulge. In the present embodiment, when the first elastic wire 27 and the second elastic wire 47 are arranged so as to sandwich the convex portion of the blood vessel, the first electrode 43 and the first electrode arranged on the first elastic wire 27 The two electrodes 45 are preferably close to the vagus nerve 100. Further, the elastic wires (27, 47, 48, 49, 50, 51) that move over the convex portion of the superior vena cava 102 by the trachea 103 hardly occur, and the elastic wire portion in the circumferential direction of the superior vena cava 102 26 rotational movement is unlikely to occur. That is, the first electrode 43 and the second electrode 45 are not easily displaced in the circumferential direction of the superior vena cava 102.

  Further, since the first inclined portion 29 and the second inclined portion 35 are inclined with respect to the vascular axis direction of the superior vena cava 102, the first inclined portion 29 and the second inclined portion 35 are resistant to movement with respect to the inner wall of the blood vessel. It becomes. For this reason, the positional displacement of the first electrode 43 and the second electrode 45 in the direction along the blood vessel axis direction of the superior vena cava 102 hardly occurs.

  The heparin that is slowly released from the distal opening 20 shown in FIG. 2 rides the blood flow and is delivered to the distal end tip 41. As a result, it is possible to reduce thrombus generation at a location located between the proximal end tip 16 and the distal end tip 41.

  In recent years, in the field of treatment of heart failure, it has become clear that the prognosis worsens when chronic heart failure worsens, by using a nerve stimulation device that directly applies electronic intervention to the autonomic nerve, It has become known that circulatory abnormalities can be corrected.

  By using the medical electrical stimulation electrode 2, it is possible to reduce the remodeling phenomenon that occurs after the reperfusion treatment at the time of acute myocardial infarction. By electrically stimulating the vagus nerve 100 and continuing heart rate reduction for a certain period after reperfusion treatment, the cardiac load can be reduced, and the increase in cytokines with anti-inflammatory action can reduce the onset of remodeling. it can. After a certain period of treatment, the medical electrical stimulation electrode 2 can be removed from the living body to complete the treatment.

  The medical electrical stimulation electrode 2 is suitable for short-term nerve stimulation unlike a long-term nerve stimulation system in which the entire electrode is implanted in the body. The pulse generator 60 serving as an electrical stimulation device is installed outside the body, and the medical electrical stimulation electrode 2 can be removed after a short-term treatment. At the time of extraction, each elastic wire (27, 47, 48, 49, 50, 51) made of shape memory alloy shrinks according to the blood vessel diameter and can be extracted from a small wound. Do not need.

  The blood vessel shape in the living body has various shapes depending on the part. However, since the elastic wire portion 26 of the present embodiment is formed of six elastic wires, the elastic wire portion 26 is deformed in response to various blood vessel shapes, and is surely connected to the plus-side electrical stimulation electrode (first electrode 43). The negative side electrical stimulation electrode (second electrode 45) is brought into contact with the inner wall of the blood vessel, and electrical stimulation can be performed on the vagus nerve 100 outside the blood vessel.

  Further, the inclined portions (the first inclined portion 29 and the second inclined portion 35) where the plus-side electrical stimulation electrode (first electrode 43) and the minus-side electrical stimulation electrode (second electrode 45) are formed are elastic wire portions 26. It has an arc shape protruding outward in the radial direction, can deform the blood vessel outward, and can be pressed toward the vagus nerve 100. As a result, the distance between the first electrode 43 and the second electrode 45 and the vagus nerve 100 can be narrowed, the impedance during electrical stimulation can be lowered, and the nerve stimulation effect can be obtained with low energy electrical stimulation energy.

Further, the first inclined portion 29 and the second inclined portion 35 are formed near the maximum diameter portion in the direction orthogonal to the central axis of the elastic wire portion 26 when the elastic wire portion 26 has a substantially spherical shape. . For this reason, the first inclined portion 29 and the second inclined portion 35 can strongly press the first electrode 43 and the second electrode 45 against the inner wall of the blood vessel.
Thereby, it can prevent that the electrical energy by electrical stimulation leaks in the blood.

  The 1st inclination part 29 and the 2nd inclination part 35 have the shape curved along the inner wall face of the blood vessel, and are pressed by the inner wall face of the blood vessel. For this reason, the first inclined portion 29 and the second inclined portion 35 can be brought into surface contact with the inner wall surface of the blood vessel in a region having a long strip shape in the direction in which each of the first inclined portion 29 and the second inclined portion 35 extends. It is. Accordingly, the first inclined portion 29 and the second inclined portion 35 are less likely to be displaced in the blood vessel axis direction as compared with the case where the first inclined portion 29 and the second inclined portion 35 are not inclined.

Since the first electrode 43 disposed on the first inclined portion 29 and the second electrode 45 disposed on the second inclined portion 35 are both arranged obliquely with respect to the traveling direction of the vagus nerve 100, a little Even if the radial displacement occurs in the first electrode 43 or the second electrode 45, the first electrode 43 and the second electrode 45 are located within the travel range of the vagus nerve 100, and the effect of electrical stimulation is difficult to reduce.
Even if a slight displacement in the vascular axis direction occurs, the vagus nerve 100 runs parallel to the vascular axis direction by more than 10 mm, so the electrodes are located within the running range of the vagus nerve 100 and are caused by electrical stimulation. The effect is difficult to reduce.

  According to the present embodiment, when electrical stimulation is performed on the nerve tissue, the stimulation is transmitted through the blood vessel wall, so that the target nerve stimulation is realized without any surgical invasion to the target nerve tissue. can do. In particular, it is possible to prevent a positional shift that occurs after the medical electrical stimulation electrode 2 is placed in the blood vessel, and to continue stable treatment.

[First Modification]
Next, the 1st modification of the medical electrical stimulation apparatus 1 which concerns on this embodiment is demonstrated. FIG. 15 is a view showing a modified example of the medical electrical stimulation electrode according to this embodiment, and is a cross-sectional view at the same site as the VV line of FIG.
As shown in FIG. 15, in this modification, instead of the second elastic wire 47, the fourth elastic wire 49, and the sixth elastic wire 51, the protruding direction in the circumferential direction of the electrode portion 15 at each intermediate portion is as follows. It has a second elastic wire 47A, a fourth elastic wire 49A, and a sixth elastic wire 51A that are bent so as to be opposite to those of the first embodiment.

  Thus, the protruding direction in the circumferential direction of the electrode portion 15 at the intermediate portion of each elastic wire is not limited to the example shown in the first embodiment, and may be formed in various directions to prevent misalignment. In this respect, the modification and the first embodiment can obtain substantially the same operations and effects.

[Second Modification]
Next, another modification of the first embodiment will be described. FIG. 16 is a diagram showing another modification of the medical electrical stimulation electrode according to the present embodiment, and is a diagram showing a process during use of the medical electrical stimulation electrode of the present modification. 17 is a cross-sectional view taken along line XVII-XVII in FIG.

  As shown in FIGS. 16 and 17, this modification is suitable for an application in which the heart branch 101 of the vagus nerve 100 is electrically stimulated. That is, in this modification, the installation positions of the plus-side electrical stimulation electrode (first electrode 43) and the minus-side electrical stimulation electrode (second electrode 45) formed on the medical electrical stimulation electrode 2 are different from those in the first embodiment. .

In the configuration shown in this modification, the first electrode 43 and the second electrode 45 are both in the indwelling site having a cross-sectional shape flattened in the direction of the trachea 103 in the superior vena cava 102 as in the first embodiment. Unlike the first embodiment, the first electrode 43 and the second electrode 45 are placed in close proximity to the heart branch 101 of the vagus nerve 100.
Specifically, in this modification, the first electrode 43 and the second electrode 45 are provided on the second elastic wire 47 described in the first embodiment. The elastic wire portion 26 is elastically deformed so as to avoid swelling of the flat portion of the superior vena cava 102.

  Similarly to the first embodiment, this modification also sandwiches the bulge of the portion located on the trachea 103 side in the superior vena cava 102. Therefore, the first electrode 43 and the second electrode in the radial direction and the circumferential direction of the blood vessel axis. An effect is obtained in which the displacement of the electrode 45 is less likely to occur.

  Moreover, in this modification, since the first electrode 43 and the second electrode 45 can be placed opposite to the heart branch 101, the vagus nerve 100 reaching only the heart can be electrically stimulated, and other organs can be stimulated. The electrical stimulation effect can be reduced. That is, it is possible to reduce the occurrence of biological phenomena such as cough.

  In addition, in addition to the position described in the first embodiment, the first electrode 43 and the second electrode 45 are further provided at the position described in this modification, thereby enhancing the nerve stimulation effect of the vagus nerve 100. Is possible.

  In addition, as described in the first embodiment, in the configuration in which the first electrode 43 and the second electrode 45 are arranged on the first elastic wire 27, the electrode unit 15 is rotated about 60 °, An electrode arrangement similar to that of the present modification can also be adopted, and in this case as well, electrical stimulation can be performed on the heart branch 101 in the same manner.

[Second Embodiment]
Next, a medical electrical stimulation electrode 2 according to a second embodiment of the present invention will be described. 18 is a view showing a part of the medical electrical stimulation electrode according to the second embodiment of the present invention, and is a cross-sectional view taken along the same line as the VV line of FIG. FIG. 19 is a diagram for explaining the configuration of the inclined portion in the medical electrical stimulation electrode according to the present embodiment. 20 is a view as seen from the direction of arrow XX in FIG. FIG. 21 is a view as seen from the direction of arrow XXI in FIG.

As shown in FIGS. 18, 19, 20, and 21, in the present embodiment, the first inclined portion 29 and the second inclined portion 35 described in the first embodiment are replaced with those of the first embodiment. The first elastic wire 27 has an inclined portion 70 where the number of times of bending is large.
In the present embodiment, the other elastic wires (27, 47, 48, 49, 50, 51) constituting the elastic wire portion 26 also have the inclined portion 70 of the present embodiment.

The inclined portion 70 includes a first inclined portion 29A where the first electrode 43 is disposed, a second inclined portion 35A where the second electrode 45 is disposed, an intermediate inclined portion 71, and an intermediate line portion 34A.
Unlike the first embodiment, the first inclined portion 29A and the second inclined portion 35A extend substantially parallel to each other.
The intermediate inclined portion 71 includes a third inclined portion 72 that connects the first inclined portion 29A and the intermediate line portion 34A, and a fourth inclined portion 73 that connects the intermediate line portion 34A and the second inclined portion 35A.

  The proximal end of the third inclined portion 72 is connected to the distal end of the first inclined portion 29A, and the proximal end of the intermediate line portion 34A is connected to the distal end of the third inclined portion 72. The proximal end of the fourth inclined portion 73 is connected to the distal end of the intermediate line portion 34A. The proximal end of the second inclined portion 35A is connected to the distal end of the fourth inclined portion 73. The boundary portion where the first inclined portion 29A and the third inclined portion 72 are connected may be bent or curved with a predetermined curvature. The boundary portion where the fourth inclined portion 73 and the second inclined portion 35A are connected may be bent or curved with a predetermined curvature.

  The first inclined part 29A and the third inclined part 72 may be connected via a linear structure parallel to the intermediate line part 34A, or the fourth inclined part 73 via a linear structure parallel to the intermediate line part 34A. The second inclined portion 35A may be connected.

  In the present embodiment, the first inclined portion 29A, the second inclined portion 35A, the third inclined portion 72, and the fourth inclined portion 73 each contribute as a displacement error with respect to the inner wall of the blood vessel, and thus will be described in the first embodiment. The effect of preventing misalignment is higher than that of the configuration described above.

  In the present embodiment, the portion where the first electrode 43 and the second electrode 45 are disposed is any of the first inclined portion 29A, the second inclined portion 35A, the third inclined portion 72, and the fourth inclined portion 73. The first electrode 43 is disposed on one of them, and the second electrode 45 is disposed on the other one of the first inclined portion 29A, the second inclined portion 35A, the third inclined portion 72, and the fourth inclined portion 73. Any configuration can be used. There are two sets of the first electrode 43 and the second electrode 45, one of which is arranged on the first inclined portion 29A and the third inclined portion 72, and the other set is the second inclined portion. The structure arranged on the part 35A and the fourth inclined part 73 may be used. By increasing the number of pairs of the first electrode 43 and the second electrode 45, a wider range of vagus nerves 100 can be stimulated.

  In the present embodiment, the portion where the first electrode 43 and the second electrode 45 exist when viewed from the central axis direction of the elastic wire portion 26 is longer than the first embodiment in the circumferential direction of the elastic wire portion 26. For this reason, the tolerance with respect to the position shift of the 1st electrode 43 and the 2nd electrode 45 in the circumferential direction of the blood vessel is large. For this reason, in this embodiment, the nerve stimulation effect can be maintained more stably.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. FIG. 22 is a perspective view showing an electrode portion of a medical electrical stimulation electrode according to the third embodiment of the present invention. FIG. 23 is a view as seen from the direction of arrow XXII in FIG.

As shown in FIGS. 22 and 23, in this embodiment, an elastic wire portion 26B having four elastic wires 80, 81, 82, 83 is provided in place of the elastic wire portion 26 of each of the above embodiments. Yes.
The four elastic wires 80, 81, 82, 83 are all the same shape and the same size. Among the four elastic wires 80, 81, 82, 83, the first elastic wire 80 includes a first electrode 43 and a second electrode 45 similar to those in the first embodiment. It is attached in substantially the same way.

  The elastic wire portion 26B is formed so as to spread from the central axis of the elastic wire portion 26B so as to follow a circular envelope when viewed from the central axis direction of the elastic wire portion 26B. In the present embodiment, the elastic wire portion 26B has a substantially spherical bowl shape.

  Each of the four elastic wires 80, 81, 82, 83 constituting the elastic wire portion 26B is separated from each other between the distal end and the proximal end of each elastic wire 80, 81, 82, 83. It has a substantially S-shape bent in opposite directions at a place (for example, the first bending point 80a and the second bending point 80b in the elastic wire 80). In the present embodiment, the elastic wire portion 26B is composed of four elastic wires 80, 81, 82, 83 having the same diameter and the same size.

  The first electrode 43 and the second electrode 45 are arc-shaped portions of the first elastic wire 80 in the middle portion in the central axis direction of the elastic wire portion 26B, that is, the first bending point 80a and the second bending point 80b in the first elastic wire 80. Are arranged side by side with a gap between them.

Each elastic wire 80, 81, 82, 83 made of shape memory alloy is S-shaped and meanders.
An intermediate portion between the distal end and the proximal end of each elastic wire 80, 81, 82, 83 has a curved shape extending in a direction intersecting with the central axis of the elastic wire portion 26B. An intermediate portion between the distal end and the proximal end of each elastic wire 80, 81, 82, 83 has a curved shape bulging toward the outside of the ridge in the elastic wire portion 26B having a spherical ridge shape. For this reason, the intermediate portion between the distal end and the proximal end of each elastic wire 80, 81, 82, 83 is easily adhered to the blood vessel wall with a strong force. An intermediate portion between the distal end and the proximal end of the elastic wires 80, 81, 82, 83 is the inclined portion 84 in the present embodiment.
In the present embodiment, as in the first embodiment, the first electrode 43 and the second electrode 45 are not easily displaced.

As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, a specific structure is not restricted to this embodiment, and this invention is not limited to these Examples. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the present invention. The present invention is not limited to the above description, but is limited only by the scope of the appended claims.
In addition, the constituent elements shown in the above-described embodiments and modifications can be combined as appropriate.

  According to each of the above embodiments (including modifications), the position of the electrode is stable even in a flexible and slippery vein.

DESCRIPTION OF SYMBOLS 1 Medical electrical stimulation apparatus 2 Medical electrical stimulation electrode 3 Lead part 4 Lead main body 5 Pipe line part 6 Lead tube 7 Branch block 7a Through hole 7b Branch hole 8 Liquid supply tube 9 Connector 10 Connection cable 11 Adapter 12 Wiring part 13 1st One wiring 14 Second wiring 15 Electrode portion 16 Proximal end chip 17 Chip body 18 Liquid discharge conduit 19 Proximal opening portion 20 Distal opening portion 21 Channel portion 22 Wire insertion passage 23 Lead connection portion 24 Wire connection portion 25 Multi Rectangular column portion 26 Elastic wire portion 26B Elastic wire portion 27 First elastic wire 27, 47, 48, 49, 50, 51 Elastic wire 28 Proximal bulging portion 29 First inclined portion 29A First inclined portion 30 First maximum bulging Part 31 first electrode exposed part 32 first covering part 33 first opening part 34 intermediate line part 34A intermediate line part 35 second inclined part 35A second Slanted portion 36 Second maximum bulging portion 37 Second electrode exposed portion 38 Second covering portion 39 Second opening 40 Distal bulging portion 41 Distal end tip 42 Nerve stimulation electrode 43 First electrode 44 First resin coating 45 Second electrode 46 Second resin coating 47 Second elastic wire 47A Second elastic wire 48 Third elastic wire 49 Fourth elastic wire 49A Fourth elastic wire 50 Fifth elastic wire 51 Sixth elastic wire 51A Sixth elastic wire 52 Sheath Part 53 flexible pipe part 54 ring 55 branching tube 56 for feeding liquid 56 operation part 57 polygonal hole part 60 pulse generator 70 inclined part 71 intermediate inclined part 72 third inclined part 73 fourth inclined part 80 first elastic wire 80, 81 , 82, 83 Elastic wire 80a First bending point 80b Second bending point 84 Inclined portion 100 Vagus nerve 101 Heart branch 102 Superior vena cava 103 Trachea

Claims (8)

An elongate lead having a distal end and a proximal end;
An electrode portion disposed at a distal end of the lead portion;
A wiring part inserted through the lead part and connected to the electrode part;
With
The electrode part is
A proximal end tip secured to the distal end of the lead;
An elastic wire having a first end fixed to the proximal end tip and a second end located distal to the first end;
A nerve stimulation electrode fixed to the elastic wire;
With
The elastic wire is
A direction that intersects the extension line in a plane that is fixed to the proximal end tip and includes an extension line in which the center line of the lead part extends further distally from the distal end of the lead part. An extended proximal bulge,
A proximal end is connected to a distal end of the proximal bulge portion, and is inclined with respect to a plane including both the distal end of the proximal bulge portion and the extension line, and away from the extension line. A ramp extending further distally from the distal end of the proximal bulge toward
A distal bulge portion connected to the distal end of the inclined portion and extending in a direction intersecting the extension line in a plane including both the distal end of the inclined portion and the extension line;
A medical electrical stimulation electrode comprising: 2. The inclined portion is formed in an arc shape so as to have a maximum bulging portion where a distance between the elastic wire and the extension line is maximum between a distal end and a proximal end of the inclined portion. An electrical stimulation electrode for medical use according to 1. The medical electrical stimulation electrode according to claim 2, wherein a distal end and a proximal end of the inclined portion are equidistant from the extension line. The nerve stimulation electrode is exposed to a surface on the opposite side to the surface directed to the extension line of the outer peripheral surface of the inclined portion in a region including the maximum bulging portion of the inclined portion. Fixed,
The medical electrical stimulation electrode according to claim 3, wherein the wiring part is connected to the nerve stimulation electrode through the inside of the elastic wire. The elastic wire is
A proximal end is connected to a distal end of the inclined portion, and a second maximum bulge portion where a distance between the elastic wire and the extension line is maximum is between the distal end and the proximal end of the inclined portion. A second inclined portion extending in an arcuate shape so as to substantially overlap the inclined portion when viewed from a direction in which the extension line extends, and having a distal end connected to a proximal end of the distal bulge portion. Have
The nerve stimulation electrode is
In the region including the maximum bulge portion in the inclined portion, the first electrode is exposed to a surface on the opposite side of the outer peripheral surface of the inclined portion and facing the extension line and is fixed to the inclined portion. When,
In the region including the second maximum bulge portion in the second inclined portion, the second inclined portion is exposed on a surface opposite to the surface directed to the extension line in the outer peripheral surface of the second inclined portion. A second electrode fixed to the part,
The wiring part is
A first wiring connected to the first electrode through the elastic wire;
A second wiring connected to the second electrode through the elastic wire;
With
The medical electrical stimulation electrode according to claim 4, wherein the distal bulge portion is connected to the inclined portion via the second inclined portion. The electrode portion is a symmetric elastic member having a plane symmetrical shape with a plane that passes through the elastic wire and is not provided with the nerve stimulation electrode and is not provided with the nerve stimulation electrode. Have wires,
The electrode part is
1 said elastic wire;
One or more isoelastic wires of the same shape and size as the elastic wire and not including the nerve stimulation electrode;
A number of the symmetric elastic wires equal to the sum of the quantities of the elastic wires and the same-type elastic wires;
The medical electrical stimulation electrode according to claim 5, comprising: The elastic wire connects the distal end of the inclined portion and the proximal end of the second inclined portion, and the distance to the extension line is each of the maximum bulge portion and the second maximum bulge portion. The medical electrical stimulation electrode according to claim 5 or 6, which has an intermediate line portion shorter than a distance to the extension line. The medical electrical stimulation electrode according to any one of claims 1 to 7,
A pulse generator that generates a predetermined electrical stimulation pulse that is connected to the wiring unit and stimulates the vagus nerve and outputs the pulse to the electrode unit;
With
The electrode part is
It has a hook shape larger than the inner diameter of the superior vena cava when no external force is applied, and has the elastic wire and another wire that defines the hook shape separately from the elastic wire. ,
The elastic wire and the other wire are formed in a convex shape between the elastic wire and the other wire in a region where the superior vena cava is pressed by the trachea and deformed in a convex shape toward the inside of the blood vessel. A medical electrical stimulation device that can be elastically deformed so as to be positioned and can be placed in the superior vena cava.

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