JP2015188483A - Nerve-stimulating electrode and nerve-stimulating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nerve-stimulating electrodes capable of being reliably held at an indwelling position after being indwelled.SOLUTION: A nerve-stimulating electrode 20 indwelled in a living body and providing an electric stimulus to nerves includes: stimulating electrodes 33A, 33B for applying an electric stimulus to nerves; an elastically deformable energization part 31; an indwelling part 30 for holding the stimulating electrodes within a living body; a lead part 21 for connection between a stimulus generating device which generates electric stimuli and the indwelling part; and an engaging part 40 having a pointed edge and mounted to the lead part such that the edge goes in a direction away from the axis of the lead part. The engaging part is adapted such that the edge projects further in a radially outward direction of the lead part than the energization part in a natural state.

Description

  The present invention relates to a nerve stimulation electrode, and more particularly, to a nerve stimulation electrode that is placed in a blood vessel and used for nerve stimulation treatment, and a nerve stimulation system including the same.

  Conventionally, research on treatment methods by applying electrical stimulation to nerve tissue has been performed. As one of the nerve stimulation devices, it has been proposed to insert a device including an electrode into a blood vessel and stimulate the nerve adjacent to the blood vessel through the blood vessel wall by the electrode (see, for example, Patent Document 1). . It is important to fix such a device without displacement in the blood vessel, and the device is placed in the blood vessel using a mesh-like or cage-like biasing member such as a stent.

Special table 2010-516405 gazette

In the device described in Patent Document 1, the biasing member is configured to expand from a folded shape to a pre-shaped expanded shape, and the expanded-shaped biasing member positions the device in the blood vessel. Hold.
However, the vessel wall is elastic and flexible, and its inner surface is smooth. In the mechanism described in Patent Document 1, the holding force that can be placed in the blood vessel after device placement may not always be sufficient. In this case, for example, the electrode may move from the indwelling position due to the patient's body movement, etc., which may reduce the stimulation effect or stimulate other organs, which is a problem.

This invention is made | formed in view of the said situation, Comprising: It aims at providing the nerve stimulation electrode which can be hold | maintained in an indwelling position more reliably after indwelling.
Another object of the present invention is to provide a nerve stimulation system in which unintentional movement of the nerve stimulation electrode after placement is unlikely to occur.

  A first aspect of the present invention is a nerve stimulation electrode that is placed in a living body and performs electrical stimulation on nerves, and includes a stimulation electrode that applies the electrical stimulation to nerves and an elastically deformable biasing portion. An indwelling part that holds the stimulation electrode in the living body, a lead part that connects the stimulation generator that generates the electrical stimulation and the indwelling part, and a pointed tip, the tip of the lead part A locking portion attached to the lead portion so as to be away from the axis, and the locking portion is in a natural state where the tip is more radially outward than the biasing portion. It is characterized by protruding.

The locking portion may include a first locking portion whose distal end is directed toward the distal end side of the lead portion, and a second locking portion whose distal end is directed toward the proximal end side of the lead portion.
At this time, one end may be further provided with an auxiliary line attached to the tip of the second locking portion, and the other end attached to the lead portion.

  Another nerve stimulation electrode of the present invention is a nerve stimulation electrode that is placed in a living body and performs electrical stimulation on a nerve, and includes a stimulation electrode that applies the electrical stimulation to the nerve and a biasing portion that can be elastically deformed. And an indwelling part for holding the stimulation electrode in the living body, a lead part for connecting the stimulation generating device for generating the electrical stimulation and the indwelling part, and a pointed tip attached to the lead part. The engaging portion is coiled in a natural state, and the tip protrudes outward from the loop of the coil.

  Still another nerve stimulation electrode according to the present invention is a nerve stimulation electrode that is placed in a living body and electrically stimulates a nerve, and includes a stimulation electrode that applies the electrical stimulation to the nerve, and an elastically deformable biasing portion. An indwelling unit for holding the stimulation electrode in the living body, a lead unit for connecting the indwelling unit to the stimulation generator for generating the electrical stimulation, a rod-shaped member, and the rod-shaped member A locking member for positioning and holding the stimulation electrode in the living body by fixing the linear member to the lead portion in a state where the rod-shaped member is locked to the living tissue. It is characterized by providing.

  A second aspect of the present invention is a nerve stimulation system comprising the nerve stimulation electrode of the present invention and the stimulation generator connected to the lead portion.

According to the nerve stimulation electrode of the present invention, it can be reliably held at the indwelling position after the indwelling.
Moreover, according to the nerve stimulation system of this invention, the unintentional movement of the nerve stimulation electrode after placement can be suppressed suitably.

It is a mimetic diagram showing the whole nerve stimulation system composition concerning a first embodiment of the present invention. It is a figure which shows the nerve stimulation electrode of the same nerve stimulation system. It is an expansion perspective view of the latching | locking part in the same nerve stimulation electrode. (A) And (b) is a figure which shows one process at the time of the placement of the same nerve stimulation electrode. It is an expansion perspective view of the latching | locking part in the modification of the same nerve stimulation electrode. It is a schematic diagram which shows the state by which the nerve stimulation electrode which concerns on 2nd embodiment of this invention was detained in the blood vessel. It is an enlarged view which shows the front end side of the nerve stimulation electrode which concerns on 3rd embodiment of this invention. (A)-(c) is a figure which shows one process at the time of the indwelling of the same nerve stimulation electrode.

A first embodiment of the present invention will be described with reference to FIGS. 1 to 4B.
FIG. 1 is a schematic diagram showing an overall configuration of a nerve stimulation system 1 of the present embodiment. The nerve stimulation system 1 is for electrically stimulating the vagus nerve Vn of a patient or the like to treat tachycardia, chronic heart failure, and the like. The nerve stimulation system 1 generates a nerve stimulation signal, and the stimulation generator 10 And a nerve stimulation electrode 20 that is connected and placed in the blood vessel Bv.
In addition, in FIG. 1, the latching part mentioned later is abbreviate | omitted and shown.

FIG. 2 is a diagram illustrating the nerve stimulation electrode 20. The nerve stimulation electrode 20 is a nerve stimulation electrode of the present invention, is placed in a blood vessel of a patient or the like, applies a nerve stimulation signal generated by the stimulation generator 10 to a living tissue, and performs electrical stimulation to the nerve.
The nerve stimulation electrode 20 includes an indwelling part 30 held in the blood vessel, a lead part 21 that connects the indwelling part 30 and the stimulation generator 10, and a locking part 40 that prevents positional deviation of the indwelling part in the blood vessel. It has.

The indwelling unit 30 includes four urging units 31 and a pair of stimulation electrodes 33A and 33B attached to one of the urging units 31.
Each urging portion 31 has a rigidity that can maintain a certain shape against deformation of the indwelling blood vessel wall, and is preferably formed using, for example, a nickel-titanium superelastic wire or the like. be able to. The surface of each urging portion 31 is covered with a biocompatible resin such as polyurethane (not shown) so that the blood vessel wall is hardly damaged. On the surface of the urging portion 31, a coating or a medicine for preventing thrombus may be further arranged.

  As shown in FIG. 2, the proximal end side of each urging portion 31 is connected to the distal end portion of the lead portion 21. As shown in FIG. 2, each urging portion 31 is first in the radial direction of the lead portion 21 and at the distal end side (hereinafter referred to as the lead portion 21) from the connecting portion to the lead portion 21 in a natural state where no external force acts. , Referred to as “front”), and then bundled close to the axis of the lead portion 21 while gently curving.

  The pair of stimulation electrodes 33 </ b> A and 33 </ b> B is disposed at one middle portion in the longitudinal direction of the plurality of biasing portions 31, and the conductive electrode surface is exposed on at least a part of the outer peripheral surface. As a material of the stimulation electrodes 33A and 33B, a metal material excellent in biocompatibility is preferable, and examples thereof include a noble metal material such as a platinum iridium alloy. In the present embodiment, the stimulation electrode 33A on the distal end side is a negative electrode, and the other stimulation electrode 33B is a positive electrode, and each is connected to the stimulation generator 10 by wiring not shown. The number of stimulation electrodes is not limited to a pair, and a plurality of stimulation electrodes may be provided.

  The lead portion 21 has a known configuration including an insulating coating 22 and a connector 23, and is configured to be long and flexible. Wirings connected to the stimulation electrodes 33A and 33B and the detection electrodes 34A and 34B pass through the coating provided in the urging unit 31 and the insulating coating 22 of the lead unit 21, and through the connector 23, the stimulation generator 10. It is connected to the.

  The locking part 40 is attached to the insulating coating 22 of the lead part 21 and includes a pair of first locking parts 41 and a pair of second locking parts 42. The proximal end portions of the pair of first locking portions 41 are attached so as to face each other with the axis of the lead portion 21 interposed therebetween, and the distal end portion is directed away from the axis line toward the distal end side of the lead portion 21. It extends. The first locking portion 41 is formed of the same material as the urging portion 31, and the distal end portion 41 a of the first locking portion 41 in the natural state is closer to the axis of the lead portion 21 than the urging portion 31 in the natural state. In a spaced position.

  The base end portions of the pair of second locking portions 42 are attached so as to face each other with the axis of the lead portion 21 interposed therebetween, and the tip ends are directed toward the base end side of the lead portion 21 while being separated from the axis. It extends. The second locking portion 42 is also formed of the same material as the biasing portion 31, and the distal end portion 42 a of the second locking portion 42 in the natural state is separated from the axis of the lead portion 21 more than the biasing portion 31 in the natural state. In the position. Each end portion 42 a is connected to one end portion of the auxiliary line 43, and the other end portion of each auxiliary line 43 is fixed to the lead portion 21. The auxiliary line 43 may be formed of the same material as the second locking portion 42 or may be formed of other materials such as silk thread.

  FIG. 3 is an enlarged perspective view of the locking portion 40. The first locking portions 41 and the second locking portions 42 are alternately arranged at equal intervals in the circumferential direction of the axis of the lead portion 21. The tips of the first locking portions 41 and the second locking portions 42 are pointed to such an extent that they do not slip with respect to the inner wall (blood vessel wall) of the blood vessel and do not damage the blood vessel wall excessively. Such a tip can be formed, for example, by cutting off the tip of the linear material of each locking portion in a direction intersecting the axis.

Operation during use of the nerve stimulation system 1 having the above configuration will be described.
The surgeon makes a small incision in the patient's blood vessel to form an opening, and inserts a cylindrical introducer or the like into the blood vessel. Then, each urging portion 31 of the indwelling portion 30 is deformed into a linear shape along the axis of the lead portion 21 and then inserted into a tubular member such as a sheath, and the tubular member is inserted into an introducer or the like. When the distal end portion of the tubular member is moved to the indwelling site close to the vagus nerve and the indwelling portion 30 protrudes from the distal end of the tubular member, first, as shown in FIG. The stimulation electrodes 33A and 33B are held in the blood vessel in a state where the stimulation electrodes 33A and 33B are in contact with the inner wall of the blood vessel Bv (blood vessel wall Vw) and in contact with the blood vessel wall.

When the surgeon retracts the tubular member 100 while maintaining the position of the indwelling portion 30, the first locking portion 41 and then the second locking portion 42 protrude from the tubular member 100. As shown in FIG. 4B, the distal ends of the first locking portion 41 and the second locking portion 42 are locked to the blood vessel wall Vw so as to be lightly stabbed or sunk into the blood vessel wall Vw.
When finely adjusting the position of the indwelling portion 30, the tubular member 100 is moved forward to accommodate the first locking portion 41 and the second locking portion 42 in the tubular member.

  When the position of the indwelling portion 30 is determined, the operator removes the introducer by removing or tearing it, and the indwelling procedure is finished. As a result, the nerve stimulation electrode 20 is placed at a predetermined position in the blood vessel Bv of the patient. The tubular member 100 may or may not be removed.

  During the placement of the nerve stimulation electrode 20, the stimulation generator 10 generates a nerve stimulation signal according to a preset program, an operation input by a user, a doctor, or the like, and applies the nerve stimulation signal to the stimulation electrodes 33A and 33B. Treatment is performed by stimulating the vagus nerve Vn through the blood vessel wall by electrical stimulation applied to the tissue from the stimulation electrodes 33A, 33B.

  After placement of the nerve stimulation electrode 20, a force that moves the placement portion 30 in the blood vessel may act on the nerve stimulation electrode 20 due to patient movement or the like. As a result, when the indwelling part 30 tries to move in a direction approaching the heart Ht (see FIG. 1), the distal end of the first locking part 41 tries to move so as to penetrate deeply into the blood vessel wall Vw, and reaction force is generated from the blood vessel wall. receive. Further, when the indwelling part 30 tries to move away from the heart Ht, the distal end of the second locking part 42 tries to move deeply into the blood vessel wall Vw, and also receives a reaction force from the blood vessel wall. As a result, the indwelling part 30 does not move in any of the longitudinal directions of the lead part 21 and maintains the position immediately after the indwelling. Further, the locking portion 40 locked to the blood vessel wall also prevents the indwelling portion 30 from rotating around the axis of the lead portion in the blood vessel. That is, the locking portion 40 is held in the blood vessel so as to position the indwelling portion 30 in the longitudinal direction and the circumferential direction of the lead portion 21.

  According to the nerve stimulation system 1 and the nerve stimulation electrode 20 of the present embodiment, the indwelling portion has a pointed tip, and the tip is provided with the locking portion 40 facing in a direction away from the axis of the lead portion 21. Even if an unintended external force or the like acts on 30, the positional relationship immediately after placement is suitably maintained. As a result, it is possible to perform treatment while suitably suppressing the attenuation of the treatment effect due to the displacement of the indwelling portion 30 and the occurrence of a situation of stimulating tissues other than nerves.

  In addition, since the locking portion 31 has a first locking portion 41 whose tip is directed to the distal end side of the nerve stimulation electrode 20 and a second locking portion 42 whose tip is directed to the proximal end side of the nerve stimulation electrode 20, The positional deviation of the lead portion 21 in both the longitudinal directions can be reliably suppressed.

Further, since the auxiliary line 43 is connected to the second locking part 42, the auxiliary line 43 is provided when the second locking part 42 is accommodated in the tubular member for fine adjustment of the position of the indwelling part 30. Smoothly accommodated as a guide. As a result, fine adjustment of the indwelling position can be easily performed.
When the auxiliary line 43 is not provided, the housing operation of the second locking portion 42 is slightly complicated, but the housing itself is possible. Therefore, the auxiliary line is not an essential configuration in the present embodiment.

  The structure of the latching | locking part of this embodiment is not restricted to what was mentioned above, It can change variously. The number of the engaging portions may be at least a pair, and may be provided as an odd number such as 3 or a large number such as 8 as in the engaging portion 40A of the modification shown in FIG. However, it should be noted that if the number is too large, the locking portion may inhibit blood flow and cause thrombus formation.

  Moreover, it is not essential to provide the first locking portion and the second locking portion, and the locking portion has a certain effect of preventing misalignment even in a configuration having only one of them. Furthermore, the front end of the locking portion only needs to extend in a direction away from the axis of the lead portion, and does not necessarily have to go toward the front end side or the separation side of the lead portion. Therefore, like the locking part 40A of the modified example described above, it may be arranged so as to extend perpendicularly to the axis of the lead part 21.

  Next, a second embodiment of the present invention will be described with reference to FIG. The difference between this embodiment and the first embodiment is the mode of the locking portion. In the following description, the same components as those already described are denoted by the same reference numerals and redundant description is omitted.

  FIG. 6 is a view showing a state in which the nerve stimulation electrode 50 of this embodiment is placed in a blood vessel. The locking portion 51 of the nerve stimulation electrode 50 is formed of the same material as the locking portion of the first embodiment and has a pointed tip. However, in a natural state, it is coiled and the tip is a loop of the coil. It is attached to protrude outside. The locking portion 51 is not fixed to the lead portion 21 before being placed, and can be freely moved relative to the lead portion.

When the nerve stimulation electrode 50 is placed, the locking portion 51, the lead portion 21 and the holding portion 30 are placed at predetermined positions, and after both are placed, the locking portion 51 is fixed to the lead portion 21 and integrated. .
An example of the detention procedure of the locking part 51 will be described. The locking portion 51 is accommodated in a substantially linear shape in a tubular member 100 such as a sheath, and the target blood vessel Sv branches off from the blood vessel in which the indwelling portion 30 is indwelled while confirming with a fluoroscopic image or the like. To enter. Thereafter, when the distal end side of the locking portion 51 is protruded from the tubular member 100, the locking portion 51 returns to a coil shape, and the distal end is locked to the blood vessel wall of the target blood vessel Sv.
Any of the placement of the locking portion 51 and the placement of the lead portion 21 and the placement portion 30 may be performed first. Moreover, indwelling may be performed in the state which accommodated both in the tubular member. The method for fixing the locking portion 51 to the lead portion 21 is not particularly limited, and may be ligated with a thread-like member, or an adhesive tape or the like may be used.

  Also in the nerve stimulation electrode 50 of this embodiment, generation | occurrence | production of the position shift etc. after placement can be suppressed suitably similarly to the nerve stimulation electrode 20 of 1st embodiment.

  Moreover, since the natural shape of the latching | locking part 51 is a coil shape, it is hard to inhibit the blood flow and to raise the formation of a thrombus, while latching to the blood vessel wall reliably.

  In the present embodiment, the blood vessel in which the locking portion is indwelled is not particularly limited, and the lead portion 21 and the indwelling portion 30 may be placed in the blood vessel.

  Next, a third embodiment of the present invention will be described with reference to FIGS. The difference between the nerve stimulation electrode 60 of the present embodiment and each of the above-described embodiments is the mode of the locking portion.

FIG. 7 is a view showing the distal end side of the nerve stimulation electrode 60. The basic structure of the lead part 61 is the same as that of the lead part 21 of the first embodiment, but the lead part 61 extends to the tip side from the indwelling part 30, and the tip part 61a is slightly bent. There is an opening at the distal end of the lead portion 61, and a lumen (not shown) communicating with the opening extends to the proximal end portion of the lead portion. The distal end portion 61a is configured to be hard using metal or the like.
Although the detail of a latching | locking part is mentioned later, it is comprised by the linear member and the rod-shaped member.

A procedure for placing the nerve stimulation electrode 60 will be described.
First, in the same procedure as in the first embodiment, the urging portion 31 is protruded from the tubular member 100 and the indwelling portion 30 is placed in the blood vessel. Next, a locking portion made of a linear member and a rod-like member is accommodated in a needle tube formed of metal or the like, and the needle tube is inserted into the lumen from the proximal end side of the lead portion 61, and FIG. As shown, the needle tube 105 is projected from the tip of the lead portion 61.

The surgeon further protrudes the needle tube 105. The distal end of the needle tube 105 advances toward the blood vessel wall Vw due to the shape of the distal end portion 61a, and the orientation of the distal end is maintained even during advancement of the needle tube 105 due to the rigidity of the distal end portion 61a. The needle tube 105 is inserted into the blood vessel wall Vw as shown in FIG.
Next, the operator uses a pusher (not shown) inserted into the needle tube 105 to eject the rod-like member 63 of the locking portion 62 from the needle tube, as shown in FIG. 8B.

The rod-shaped member 63 is made of a biodegradable material such as polylactic acid (PLA). A through-hole 63a is formed in the rod-like member 63, and a linear member 64 such as silk thread is inserted into the through-hole 63a and hung around. Both ends of the linear member 64 protrude to the proximal end side of the lead portion 61 through the lumen.
After the injection of the bar-shaped member 63, the needle tube 105 is removed, and the bar-shaped member 63 of the locking portion 62 is locked to the tissue as shown in FIG. 8C. When the end of the linear member 64 is fixed to the lead portion 61, the placement of the nerve stimulation electrode 60 is completed, and the stimulation electrode (not shown) is positioned and held in the body.
After the treatment, when the nerve stimulation electrode 60 is removed, the linear member 64 is removed from the lead portion 61. When one end is pulled, the linear member 64 can be detached from the rod-shaped member 63 and removed. Although the rod-shaped member 63 remains in the body, it is decomposed in the living body and finally disappears.

Also in the nerve stimulation electrode 60 of this embodiment, generation | occurrence | production of the position shift after placement etc. can be suppressed suitably like the nerve stimulation electrode of each above-mentioned embodiment.
Further, since the rod-like member 63 of the locking portion 62 enters the tissue and is locked to the blood vessel wall Vw, the locking can be made more reliable.

Furthermore, since the distal end portion 61a of the lead portion 61 is formed rigidly, the orientation of the distal end of the needle tube 105 during the procedure is suitably held toward the blood vessel wall Vw, and the distal end of the needle tube that has advanced in the lumen Can be prevented from breaking through the lead portion.
In the present embodiment, the tip of the lead part does not necessarily extend to the tip of the indwelling part, and the tip may be located at the root of the indwelling part. However, it is preferable that the lead portion extends to the vicinity of the distal end of the indwelling portion because it hardly interferes with the urging portion 31 when the needle tube is protruded, and the grounding procedure of the locking portion is facilitated.

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

  For example, in each of the above-described embodiments, the example in which the nerve stimulation electrode is inserted into the introducer while being accommodated in the tubular member has been described. However, in the case where the length of the introducer reaches the vicinity of the indwelling site, etc. The introducer may be used as a tubular member and indwelling without using another tubular member.

DESCRIPTION OF SYMBOLS 1 Neural stimulation system 10 Stimulation generator 20, 50, 60 Nerve stimulation electrode 21, 61 Lead part 30 Indwelling part 31 Energizing part 33A, 33B Stimulation electrode 40, 40A, 51, 62 Locking part 41 First locking part 41a Tip 42 Second locking portion 42a Tip 43 Auxiliary wire 63 Bar-shaped member 64 Linear member

Claims (6)

A nerve stimulation electrode that is placed in a living body and electrically stimulates a nerve,
A stimulation electrode for applying the electrical stimulation to a nerve;
An indwelling portion having an urging portion capable of elastic deformation, and holding the stimulation electrode in the living body;
A lead portion connecting the stimulation generating device for generating the electrical stimulation and the indwelling portion;
A locking portion having a pointed tip and attached to the lead portion such that the tip is in a direction away from the axis of the lead portion;
With
The nerve stimulation electrode according to claim 1, wherein in the natural state, the distal end of the locking portion protrudes radially outward of the lead portion from the biasing portion.   The said latching | locking part has the 1st latching | locking part in which the said front end goes to the front end side of the said lead part, and the 2nd latching part in which the said front end goes to the base end side of the said lead part. Item 12. The nerve stimulation electrode according to Item 1.   3. The nerve stimulation electrode according to claim 2, further comprising an auxiliary line having one end attached to the tip of the second locking portion and the other end attached to the lead portion. A nerve stimulation electrode that is placed in a living body and electrically stimulates a nerve,
A stimulation electrode for applying the electrical stimulation to a nerve;
An indwelling portion having an urging portion capable of elastic deformation, and holding the stimulation electrode in the living body;
A lead portion connecting the stimulation generating device for generating the electrical stimulation and the indwelling portion;
A locking portion having a pointed tip and attached to the lead portion;
With
The nerve-stimulating electrode according to claim 1, wherein the locking portion is coiled in a natural state, and the tip protrudes outward from the loop of the coil. A nerve stimulation electrode that is placed in a living body and electrically stimulates a nerve,
A stimulation electrode for applying the electrical stimulation to a nerve;
An indwelling portion having an urging portion capable of elastic deformation, and holding the stimulation electrode in the living body;
A lead portion connecting the stimulation generating device for generating the electrical stimulation and the indwelling portion;
A rod-like member; and a linear member wound around the rod-like member, and fixing the stimulation electrode by fixing the linear member to the lead portion in a state where the rod-like member is locked to a living tissue. A locking portion for positioning and holding in the living body;
A nerve stimulation electrode comprising: The nerve stimulation electrode according to any one of claims 1 to 5,
The stimulus generator connected to the lead;
A nerve stimulation system comprising:

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