JPWO2016038713A1 - Neural stimulation apparatus, neural stimulation system, and neural stimulation method - Google Patents

Abstract

The nerve stimulation system includes a lead portion disposed in a blood vessel, a stimulation electrode having at least two electrodes, an electrocardiogram acquisition electrode including at least two electrodes, and a stimulation signal for generating a stimulation signal A generation unit, and a heart rate measurement unit for measuring a heart rate from the electrocardiogram acquisition electrode. The stimulation electrode and the electrocardiogram acquisition electrode are disposed on the same lead portion.

Description

  The present invention relates to a nerve stimulation apparatus, a nerve stimulation system, and a nerve stimulation method. More specifically, a nerve stimulation device including an electrode that is placed in a blood vessel and stimulates nerves, a nerve stimulation system that arranges a lead in the blood vessel, stimulates the vagus nerve, and treats arrhythmia such as tachycardia, and nerve stimulation Regarding the method.

There is known a nerve stimulation system that treats arrhythmia by suppressing an increase in heart rate and sympathetic excitement by applying electrical stimulation to the vagus nerve via an electrode connected to the vagus nerve.
In this nerve stimulation system, it is known that a heart rate decrease as a biological reaction of nerve stimulation can be used as an index of a stimulation effect.
In general, as a heart rate measurement method, a method is used in which an electrocardiogram waveform generated in the heart is captured and the heart rate is calculated from the peak interval of the waveform.
Therefore, a nerve stimulation system that performs feedback based on the heart rate using a heart treatment lead installed in the heart has been proposed (see, for example, Patent Document 1).
Conventionally, research on treatment methods by applying electrical stimulation to nerve tissue has been performed. As a nerve stimulating device used for such applications, it has been proposed to place an electrode in a blood vessel and stimulate the nerve adjacent to the blood vessel through the blood vessel wall by the electrode. Examples of the nerve to be treated include a vagus nerve, and stimulating this brings about a desired effect such as lowering the heart rate.
In the case of treatment that stimulates the vagus nerve, it is necessary to perform stimulation by detecting an event such as an increase in heart rate or tachycardia. For this reason, a mechanism for detecting biological information such as a heart rate and an electrocardiographic waveform is connected to the nerve stimulation device, and the input biological information is monitored.
In the nerve stimulation device described in Patent Document 2, an electrocardiogram signal is acquired by a plurality of bipolar leads placed in a blood vessel. This bipolar lead is configured to allow cardiac pacing in addition to the acquisition of an electrocardiographic signal.

Japanese National Special Table 2010-534681 Japan Special Table 2007-510467

In the nerve stimulation system described in Patent Document 1, since the heartbeat detecting means is placed in the heart, there is a problem that it cannot be said that the invasion given to the patient is small.
On the other hand, although it is conceivable to install a heartbeat detecting means on the body surface, the invasion is reduced, but annoyance occurs when the number of electrodes to be installed is increased.
In the nerve stimulation device described in Patent Document 2, an electrode that performs nerve stimulation and a bipolar lead that acquires an electrocardiographic signal are disposed close to each other in blood with low electrical impedance. Therefore, when nerve stimulation is performed, there is a possibility that the electrocardiogram signal cannot be correctly detected due to the influence of the stimulation pulse. When noise derived from a stimulation pulse is mixed into an electrocardiogram signal, there is a problem that it is difficult to correctly measure the heart rate.
The present invention has been made in view of the above-described problems. A nerve stimulation system and a nerve stimulation method capable of performing vagus nerve stimulation and heart rate measurement with a simple configuration, and an electrocardiographic signal more accurately. An object of the present invention is to provide a neurostimulator that can be obtained.

  According to the first aspect of the present invention, a nerve stimulation system includes a lead portion disposed in a blood vessel, a stimulation electrode having at least two electrodes, and an electrocardiogram acquisition electrode including at least two electrodes. A stimulation signal generating unit for generating a stimulation signal, and a heart rate measuring unit for measuring a heart rate from the electrocardiogram acquisition electrode. The stimulation electrode and the electrocardiogram acquisition electrode are disposed on the same lead portion.

  According to the second aspect of the present invention, a nerve stimulation system includes a lead portion disposed in a blood vessel, a stimulation electrode composed of at least two electrodes, a one-electrode electrocardiogram acquisition electrode, and a stimulation signal. A stimulation signal generating unit for generating, a heart rate measuring unit for measuring a heart rate from the electrocardiogram acquisition electrode, and switching for switching the connection to the stimulation signal generating unit and the heart rate measuring unit connected to the stimulation electrode Means. The stimulation electrode and the electrocardiogram acquisition electrode are disposed on the same lead portion. When applying neural stimulation, the switching means performs switching so as to connect the stimulation electrode to the stimulation signal generator, and when acquiring an electrocardiogram, the switching means measures one of the stimulation electrodes as the heart rate. Switch to connect to one input / output of the unit.

  According to the third aspect of the present invention, in the nerve stimulation system according to the first aspect or the second aspect, switching is performed so that the two electrodes of the stimulation electrode have the same potential when an electrocardiogram is acquired. May be.

  According to the fourth aspect of the present invention, the nerve stimulation method uses a stimulation electrode having at least two electrodes and an electrocardiogram acquisition electrode composed of at least two electrodes, and is stimulated by a stimulation signal generator. A signal is generated, a heart rate is measured from an electrocardiogram acquisition electrode by a heart rate measurement unit, and nerve stimulation is performed by arranging the stimulation electrode and the electrocardiogram acquisition electrode on the same lead portion disposed in a blood vessel.

  According to the fifth aspect of the present invention, the nerve stimulation device is a nerve stimulation device that is placed in a living body and performs electrical stimulation on the nerve, and includes a stimulation electrode that applies the electrical stimulation to the nerve, and a first end portion. A nerve stimulation electrode having a lead portion connected to the stimulation electrode, a stimulation generating device connected to the second end of the lead portion and generating a nerve stimulation signal for applying the electrical stimulation, And at least one biometric information acquisition electrode provided on the lead portion so as not to be separated from the lead portion.

According to the sixth aspect of the present invention, in the nerve stimulation apparatus according to the fifth aspect, the biological information acquisition electrode provided on the lead portion has the adhesive portion, and can be adhesively fixed to the biological surface. There may be.

According to a seventh aspect of the present invention, in the nerve stimulation apparatus according to the fifth aspect or the sixth aspect, one of the biological information acquisition electrodes may be provided on the stimulation generator.

According to an eighth aspect of the present invention, in the nerve stimulation apparatus according to the seventh aspect, the biological information acquisition electrode provided on the stimulation generator has an adhesive portion and can be adhesively fixed to the biological surface. It may be.

According to a ninth aspect of the present invention, in the nerve stimulation apparatus according to any one of the fifth to eighth aspects, three or more biological information acquisition electrodes are provided, and the biological information acquisition is performed. One of the electrodes may be set as a reference electrode from which an electrocardiogram waveform is acquired.

  According to the nerve stimulation device, the nerve stimulation system, and the tissue stimulation method according to the present invention, vagus nerve stimulation and heart rate measurement can be performed with a simple configuration, and an electrocardiographic signal can be acquired more accurately. There is an effect.

It is a mimetic diagram showing the whole nerve stimulation system composition concerning a 1st embodiment of the present invention. It is a block diagram of the stimulus generator in the nerve stimulation system concerning a 1st embodiment of the present invention. It is a mimetic diagram showing the whole nerve stimulation system composition concerning the 1st modification of a 1st embodiment of the present invention. It is a schematic diagram which shows the whole structure of the nerve stimulation system which concerns on the 2nd modification of 1st Embodiment of this invention. It is a schematic diagram which shows the principal part of the nerve stimulation system which concerns on the 3rd modification of 1st Embodiment of this invention. It is a schematic diagram which shows the principal part of the nerve stimulation system which concerns on the 4th modification of 1st Embodiment of this invention. It is a schematic diagram which shows the principal part structure of the nerve stimulation system which concerns on the 5th modification of 1st Embodiment of this invention. It is a schematic diagram which shows the principal part of the nerve stimulation system which concerns on the 6th modification of 1st Embodiment of this invention. It is a schematic diagram which shows the whole structure of the nerve stimulation system which concerns on 2nd Embodiment of this invention. It is a block diagram of the stimulus generator at the time of nerve stimulation in the nerve stimulation system concerning a 2nd embodiment of the present invention. It is a block diagram of the stimulus generator at the time of heart rate measurement in the nerve stimulation system concerning a 2nd embodiment of the present invention. It is a timing chart explaining switching operation | movement of the nerve stimulation system which concerns on 2nd Embodiment of this invention. It is a schematic diagram which shows the whole structure of the nerve stimulation system which concerns on the 1st modification of 2nd Embodiment of this invention. It is a block diagram of the stimulus generator concerning the 2nd modification of a 2nd embodiment of the present invention. It is a block diagram of the stimulus generator concerning the 3rd modification of a 2nd embodiment of the present invention. It is a schematic diagram which shows the whole structure of the nerve stimulation apparatus which concerns on 3rd Embodiment of this invention. It is a functional block diagram of the nerve stimulation apparatus which concerns on 3rd Embodiment of this invention. It is a figure which shows the state by which the nerve stimulating device which concerns on 3rd Embodiment of this invention was detained in the patient. It is a schematic diagram which shows the whole structure of the modification of the nerve stimulation apparatus which concerns on 3rd Embodiment of this invention. It is a schematic diagram which shows the whole structure of the modification of the nerve stimulation apparatus which concerns on 3rd Embodiment of this invention. It is a schematic diagram which shows the whole structure of the nerve stimulation apparatus which concerns on 4th Embodiment of this invention.

(First embodiment)
Hereinafter, a nerve stimulation system according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic diagram showing an overall configuration of a nerve stimulation system 1 according to the present embodiment.
As shown in FIG. 1, the nerve stimulation system 1 includes an electrode unit 10. The electrode unit 10 includes two electrodes and includes a first stimulation electrode 11 and a second stimulation electrode 12. The nerve stimulation system 1 includes a lead portion 13 and a first electrocardiogram acquisition electrode 14 and a second electrocardiogram acquisition electrode 15 configured by two electrodes. The lead portion 13 is disposed in the blood vessel Bv of the heart H. The nerve stimulation system 1 includes a stimulation generator 16 and a heart rate measurement unit 17 (see FIG. 2). The stimulus generator 16 generates a stimulus signal. The heart rate measuring unit 17 measures the heart rate from the electrocardiogram acquisition electrodes 14 and 15. In the nerve stimulation system 1, the stimulation electrodes 11 and 12 and the electrocardiogram acquisition electrodes 14 and 15 are arranged on the same lead portion 13.

  The electrode unit 10 includes a plurality of urging portions 18. The urging unit 18 includes a first stimulation electrode 11 and a second stimulation electrode 12 that form a pair of a positive electrode and a negative electrode. Each stimulation electrode 11, 12 is placed in the patient's blood vessel Bv so as to be close to the vagus nerve Vn. Since each of the stimulation electrodes 11 and 12 is electrically connected to the stimulation generator 16, a nerve stimulation signal generated by the stimulation generator 16 is applied.

  Each urging portion 18 has such a rigidity that it can maintain a certain shape against deformation of the indwelling blood vessel wall. Each urging portion 18 can be suitably formed using, for example, a superelastic wire made of nickel titanium. The surface of each urging portion 18 is covered with a biocompatible resin such as polyurethane (not shown) so that the blood vessel wall is hardly damaged. On the surface of each urging portion 18, a coating or a medicine for preventing thrombus may be further arranged.

  The base end side of each urging portion 18 is connected to the distal end portion of the lead portion 13. The leading end portion of each urging portion 18 is bundled on the axis of the lead portion 13. In a natural state where no external force is applied, each urging portion 18 first extends from the connection portion to the lead portion 13 in the radial direction outside the lead portion 13 and toward the tip side from the tip of the lead portion 13. Thereafter, each urging portion 18 curves gently and extends forward substantially parallel to the axis of the lead portion 13. When viewed in the axial direction of the lead portion 13, each urging portion 18 extends radially away from the axial line of the lead portion 13, and is arranged at approximately equal intervals in the circumferential direction of the lead portion 13.

  The lead part 13 is a long member provided with a conducting wire inside. The lead unit 13 connects each stimulation electrode 11, 12 and a stimulation signal generation unit 19 (see FIG. 2) provided in the stimulation generator 16. Furthermore, the lead unit 13 connects the electrocardiogram acquisition electrodes 14 and 15 to the heart rate measuring unit 17 provided in the stimulus generator 16. The lead part 13 is connected to the stimulus generator 16 by a connector 21. The lead portion 13 has no protruding portion at the tip.

  The first electrocardiogram acquisition electrode 14 and the second electrocardiogram acquisition electrode 15 are located distal to the heart H and connected in series to the lead portion 13. The electrocardiogram acquisition electrodes 14 and 15 acquire the potential difference between them as an electrocardiogram waveform (electrical information) in the heart rate measurement unit 17. The heart rate measurement unit 17 performs A / D conversion on the electrocardiogram waveform and calculates the RR interval to measure the heart rate.

Next, the internal structure of the stimulus generator 16 will be described. FIG. 2 is a block diagram of a stimulus generator in the nerve stimulation system according to the present embodiment.
The stimulus generator 16 is a non-implantable device. The stimulus generation device 16 includes a heart rate measurement unit 17, a stimulus signal generation unit 19, a control unit 20, and an interface unit 22. The control unit 20 is connected to the heart rate measurement unit 17 and the stimulus signal generation unit 19. The interface unit 22 is connected to the control unit 20.

  The heart rate measurement unit 17 is connected to the first electrocardiogram acquisition electrode 14 via the connector 21 through the first connection line 23. The heart rate measurement unit 17 is connected to the second electrocardiogram acquisition electrode 15 via the connector 21 through the second connection line 24. The heart rate measurement unit 17 is connected to the control unit 20 through the third connection line 25. The heart rate measurement unit 17 acquires the electrical information acquired by the electrocardiogram acquisition electrodes 14 and 15 at a predetermined timing, and measures the heart rate based on the electrical information.

The stimulation signal generator 19 is connected to the first stimulation electrode 11 via the connector 21 through the fourth connection line 26. The stimulation signal generator 19 is connected to the second stimulation electrode 12 via the connector 21 through the fifth connection line 27. The stimulus signal generator 19 is connected to the controller 20 through the sixth connection line 28. For this purpose, the stimulation signal generator 19 generates a neural stimulation signal having a predetermined pulse width and voltage value at a predetermined timing instructed to the controller 20 (constant voltage control). The stimulation intensity may be specified by specifying a current value instead of the voltage value (constant current control).
The generated nerve stimulation signal is sent to the stimulation electrodes 11 and 12 through the lead portion 13 and applied to the vagus nerve Vn.

  The first connection line 23 is connected to the seventh connection line 29. The seventh connection line 29 is connected to the first electrocardiogram acquisition electrode 14 via the connector 21. The second connection line 24 is connected to the eighth connection line 30. The eighth connection line 30 is connected to the second electrocardiogram acquisition electrode 15 via the connector 21. The fourth connection line 26 is connected to the ninth connection line 31. The ninth connection line 31 is connected to the first stimulation electrode 11 via the connector 21. The fifth connection line 27 is connected to the tenth connection line 32. The tenth connection line 32 is connected to the second stimulation electrode 12 via the connector 21.

  The control unit 20 includes a calculation unit such as a CPU and a storage unit such as a memory. The control unit 20 instructs and controls the acquisition of the electrical information of the heart rate measurement unit 17 and the timing of generating the nerve stimulation signal of the stimulation signal generation unit 19 in accordance with the program stored in the storage unit. The control unit 20 obtains a peak interval from the obtained electrocardiogram signal and calculates a heart rate.

  The interface unit 22 has a known configuration such as a liquid crystal screen (including a touch panel) and buttons. The interface unit 22 displays the heart rate measured by the heart rate measuring unit 17, accepts a user operation input to the stimulus generator 16, and sends it to the control unit 20.

As described above, according to the nerve stimulation system 1 according to the first embodiment, the vagus nerve stimulation of the blood vessel Bv and the electrocardiogram acquisition can be acquired by the single lead unit 13.
Therefore, according to the nerve stimulation system 1 which concerns on 1st Embodiment, compared with the conventional nerve stimulation system, it can implement | achieve with a very simple structure.

  Moreover, according to the nerve stimulation system 1 which concerns on 1st Embodiment, since there is no protrusion part in the front-end | tip of the lead part 13, insertion property is excellent.

According to the nerve stimulation method according to the first embodiment, the vagus nerve stimulation of the blood vessel Bv and the electrocardiogram acquisition are performed by one lead portion 13.
Therefore, according to the nerve stimulation method which concerns on 1st Embodiment, it can implement with a very simple structure compared with the related nerve stimulation system.

  Next, a modification of this embodiment will be described. FIG. 3 is a schematic diagram illustrating an overall configuration of a nerve stimulation system according to a first modification of the present embodiment. FIG. 4 is a schematic diagram illustrating an overall configuration of a nerve stimulation system according to a second modification of the present embodiment. FIG. 5 is a schematic diagram illustrating a main part of a nerve stimulation system according to a third modification of the present embodiment. FIG. 6 is a schematic diagram illustrating a main part of a nerve stimulation system according to a fourth modification of the present embodiment. FIG. 7 is a schematic diagram illustrating an overall configuration of a nerve stimulation system according to a fifth modification of the present embodiment. FIG. 8 is a schematic diagram showing a main part of a nerve stimulation system according to a sixth modification of the present embodiment.

Like the nerve stimulation system 35 shown in FIG. 3, the first electrocardiogram acquisition electrode 14 may be configured to connect to the tip of the biasing portion 18 proximal to the heart H (see FIG. 1). . The second electrocardiogram acquisition electrode 15 is connected to the lead portion 13 distal to the heart H.
According to the present embodiment, since the first electrocardiogram acquisition electrode 14 is disposed in the vicinity of the heart H, the voltage level of the signal is increased. As a result, it is possible to acquire an electrocardiographic signal with a good S / N ratio, and the heart rate generated by the heart H can be accurately acquired.
Further, according to the present embodiment, since the distances between the electrocardiogram acquisition electrodes 14 and 15 are separated, it is easy to detect a potential difference.

Moreover, in this embodiment, it is comprised so that the extension lead part 41 arrange | positioned in the heart H (refer FIG. 1) may be provided in the front-end | tip part of the urging | biasing part 18 like the nerve stimulation system 40 shown in FIG. May be. The electrocardiogram acquisition electrodes 14 and 15 are connected to the extension lead portion 41 so as to be positioned on the extension line of the lead portion 13.
According to this embodiment, since the electrocardiogram acquisition electrodes 14 and 15 are disposed in the heart H, the heart rate generated by the heart H can be acquired more accurately.
Moreover, according to this embodiment, since each electrocardiogram acquisition electrode 14 and 15 is arrange | positioned in the heart H, an electrocardiogram with a high voltage level is acquirable.

In the present embodiment, a mesh anchor 46 may be attached to the urging unit 18 as in the nerve stimulation system 45 shown in FIG. The electrocardiogram acquisition electrodes 14 and 15 are connected in series to the lead portion 13 distal to the heart H (see FIG. 1).
According to this embodiment, the flow of blood flow is promoted by the mesh anchor 46.
Therefore, according to the present embodiment, it is possible to prevent the blood flow from becoming stagnant, slowing down, backflowing, or coughing, preventing the formation of blood clots, and accurately adjusting the heart rate. Can be obtained.

In this embodiment, like the nerve stimulation system 50 shown in FIG. 6, you may comprise so that the urging | biasing part 51 of the mesh anchor shape of a stent specification may be provided. Each stimulation electrode 11, 12 is connected to one of the urging units 51, and each electrocardiogram acquisition electrode 14, 15 is connected in series to the lead portion 13 distal to the heart H (see FIG. 1). Yes.
According to the present embodiment, the flow of blood flow is promoted by the mesh anchor-shaped biasing portion 51.
Therefore, according to the present embodiment, it is possible to prevent the blood flow from becoming stagnant, slowing down, backflowing, or coughing, preventing the formation of blood clots, and accurately adjusting the heart rate. Can be obtained.

In this embodiment, like the nerve stimulation system 55 shown in FIG. 7, you may comprise so that the urging | biasing part 56 which has a helical structure may be provided. The stimulation electrodes 11 and 12 are connected to the biasing portion 56, and the electrocardiogram acquisition electrodes 14 and 15 are connected in series to the lead portion 13 distal to the heart H (see FIG. 1). May be. In this case, the lead portion 13 has a function of maintaining the flow path of the blood vessel Bv by being close to the blood vessel wall of the blood vessel Bv.
Since the nerve stimulation system 55 according to the present modification is provided with the urging portion 56 having a spiral structure, it is possible to prevent the blood flow from being inhibited.
Therefore, according to the present embodiment, it is possible to prevent the blood flow from becoming stagnant, slowing down, backflowing, or coughing, preventing the formation of blood clots, and accurately adjusting the heart rate. Can be obtained.

In the present embodiment, the nerve stimulation system 60 shown in FIG. 8 may be configured to include a pair of U-shaped biasing portions 61 and extension lead portions 62 having a spring structure. The extension lead part 62 is disposed on an extension line of the axis of the lead part 13. Energizing portions 61 are connected to both ends of the extension lead portion 62. Furthermore, the stimulation electrodes 11 and 12 are connected to the biasing portion 61, and the electrocardiogram acquisition electrodes 14 and 15 are connected in series to the lead portion 13 distal to the heart H (see FIG. 1).
According to this embodiment, the flow of blood flow is promoted by the pair of U-shaped biasing portions 61 having a spring structure.
Therefore, according to the present embodiment, it is possible to prevent the blood flow from becoming stagnant, slowing down, backflowing, or coughing, preventing the formation of blood clots, and accurately adjusting the heart rate. Can be obtained.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. 9 to 15. However, the same parts as those in the first embodiment are denoted by the same reference numerals, the description thereof will be omitted, and different points will be described. Only will be described. FIG. 9 is a schematic diagram showing the overall configuration of the nerve stimulation system according to the present embodiment. FIG. 10 is a block diagram of a stimulus generation apparatus during nerve stimulation in the nerve stimulation system.
FIG. 11 is a block diagram of a stimulus generation apparatus during heart rate measurement in the nerve stimulation system.
FIG. 12 is a timing chart illustrating the switching operation of the nerve stimulation system.

  As shown in FIG. 9, the nerve stimulation system 70 according to this embodiment includes a first stimulation electrode 11 and a second stimulation electrode 12, and a single electrocardiogram acquisition electrode 71. The first stimulation electrode 11 and the second stimulation electrode 12 are connected in series to one of the urging portions 18. A single electrocardiogram acquisition electrode 71 is connected to the lead portion 13. A single electrocardiogram acquisition electrode 71 is disposed distal to the heart H. Moreover, the nerve stimulation system 70 is equipped with a stimulus generator 73 including a switching unit 72 (see FIG. 10). The switching unit 72 is connected to the stimulation electrodes 11 and 12. The switching unit 72 is a means for switching the connection between the stimulation electrodes 11 and 12 and the stimulation signal generating unit 19 (see FIG. 2) and the connection between the stimulation electrodes 11 and 12 and the heart rate measuring unit 17 (see FIG. 2). It is an example.

  As shown in FIG. 10, the switching unit 72 includes a first switch 74, a normally closed contact 79, a normally open contact 80, and a second switch 78. The first switch 74 has a normally closed contact 75, a normally open contact 76, and a movable contact 77. The second switch 78 has a movable contact 81. The normally closed contact 75 is connected to one input / output of the stimulus signal generator 19 through the eleventh connection line 82. The normally open contact 76 is connected to the normally open contact 80 of the second switch 78 and one input / output of the heart rate measuring unit 17 through the twelfth connection line 83. The normally closed contact 79 is connected to the other input / output of the stimulation signal generator 19 through the thirteenth connection line 84. The other input / output of the heart rate measuring unit 17 is connected to the electrocardiogram acquisition electrode 71 through the fourteenth connection line 85, the connector 21, and the fifteenth connection line 86. Each of the switches 74 and 78 may be a general controllable circuit switch such as an FET in addition to the illustrated analog switch, and may be configured so as to be switched by a command from the control unit 20.

  In the stimulus generator 73, when a stimulus signal is applied, the movable contact 77 of the first switch 74 is connected to the normally closed contact 75, and the movable contact 81 of the second switch 78 is connected to the normally closed contact 79. Thereby, signals are respectively sent from the stimulation signal generator 19 to the first stimulation electrode 11 and the second stimulation electrode 12. Then, the nerve stimulation signal is sent to the stimulation electrodes 11 and 12 through the lead portion 13 and applied to the vagus nerve Vn.

Next, the case of measuring the heart rate will be described with reference to FIG.
As shown in FIG. 11, the movable contact 77 of the first switch 74 is connected to the normally open contact 76, and the movable contact 81 of the second switch 78 is connected to the normally open contact 80. Therefore, a nerve stimulation signal is not output from each stimulation electrode 11, 12. Thereby, the heart rate measurement part 17 acquires the electrical information acquired with the electrocardiogram acquisition electrode 71 at a predetermined timing, and measures the heart rate based on the electrical information. At this time, each stimulation electrode 11 and 12 will be in the electrically conductive state.

Next, timings when generating a nerve stimulation signal and when measuring a heart rate will be described with reference to FIG.
As shown in FIG. 12, at the time t1 when the movable contacts 77 and 81 of the switches 74 and 78 are connected to the normally open contacts 76 and 80, the movable contacts 77 and 81 of the switches 74 and 78 are Switches to normally closed contacts 75 and 79. Thereby, at time t2, signals are sent from the stimulation signal generator 19 to the first stimulation electrode 11 and the second stimulation electrode 12, respectively. A nerve stimulation signal is sent to the stimulation electrodes 11 and 12 through the lead portion 13 and applied to the vagus nerve Vn.

  At the time t3 after the time t2, the movable contacts 77 and 81 of the switches 74 and 78 are switched to the normally open contacts 76 and 80, respectively. At time t4 after time t3, the heart rate measurement unit 17 acquires the electrical information acquired by the electrocardiogram acquisition electrode 71 at a predetermined timing, and measures the heart rate based on the electrical information. Thereafter, these operations are repeatedly executed at time t5, time t6, time t7, and time t8.

As described above, according to the nerve stimulation system 70 according to the second embodiment, the stimulation generator 73 is connected to the stimulation signal generator 19 from each stimulation electrode 11, 12 and from each stimulation electrode 11, 12. A switching unit 72 that switches connection to the heart rate measuring unit 17 is provided.
According to the nerve stimulation system 70, it is possible to realize nerve stimulation and electrocardiogram acquisition with a very simple configuration by using a single electrocardiogram acquisition electrode 71.

According to the nerve stimulation system 70, switching is performed by the switching unit 72 so that the stimulation electrodes 11 and 12 have the same potential when the electrocardiogram is acquired.
Therefore, according to the nerve stimulation system 70, the polarization imbalance at the contact surface between the stimulation electrodes 11 and 12 and the living body can be eliminated.

  The lead wire (not shown) accommodated in the lead portion 13 is usually composed of four wires. Since the nerve stimulation system 70 according to the present embodiment can be realized with three conducting wires, the diameter of the lead portion 13 can be further reduced.

  According to the nerve stimulation system 70, since the electrocardiogram acquisition electrode 71 is disposed at a position far away from each of the stimulation electrodes 11 and 12, it is possible to prevent receiving noise during nerve stimulation.

  Next, a modification of this embodiment will be described. FIG. 13 is a schematic diagram illustrating an overall configuration of a nerve stimulation system according to a first modification of the present embodiment. FIG. 14 is a block diagram of a stimulus generator according to a second modification of the present embodiment. FIG. 15 is a block diagram of a stimulus generator according to a third modification of the present embodiment.

For example, like the nerve stimulation system 90 shown in FIG. 13, a single electrocardiogram acquisition electrode 91 may be arranged proximal to the heart H at the tip of the biasing unit 18.
According to this embodiment, since the electrocardiogram acquisition electrode 91 is disposed proximal to the heart H, the heart rate generated by the heart H can be accurately acquired.
Moreover, according to this embodiment, since the electrocardiogram acquisition electrode 91 is disposed at a position close to the heart H, the level of the electrocardiogram can be detected higher.

Moreover, in this embodiment, you may be comprised so that the single switch 96 may be equipped like the nerve stimulation system 95 shown in FIG.
In this case, the switch 96 has a normally open contact 97, a normally closed contact 98, and a movable contact 99. The normally open contact 97 is connected to one input / output of the stimulus signal generator 19 through the sixteenth connection line 100. The normally closed contact 98 is connected to one input / output of the heart rate measuring unit 17 through the seventeenth connection line 101.
According to this embodiment, since it is possible to switch between nerve stimulation and electrocardiogram acquisition by a single switch 96, it can be realized with an extremely simple configuration.

Moreover, in this embodiment, you may equip the 1st switch 111 and the 2nd switch 112 like the nerve stimulation system 110 shown in FIG. The nerve stimulation system 110 may be configured to connect the normally closed contact 113 of the second switch 112 to ground when no nerve stimulation is performed.
In this case, the first switch 111 has a normally open contact 114, a normally closed contact 115, and a movable contact 116. The second switch 112 has a normally open contact 117, a normally closed contact 113, and a movable contact 118. The normally open contact 114 is connected to one input / output of the stimulus signal generator 19 through an eighteenth connection line 119. The normally closed contact 115 is connected to one input / output of the heart rate measuring unit 17 through the nineteenth connection line 120. The normally open contact 117 is connected to the other input / output of the stimulation signal generator 19 through the twentieth connection line 121. The normally closed contact 113 is connected to the ground through the twenty-first connection line 122.
According to this embodiment, the noise level of the electrocardiogram signal can be reduced by connecting the reference electrode to the ground.

In the nerve stimulation system of the present invention, a method of performing electrocardiogram acquisition by switching the nerve stimulation electrodes in a circuit manner is also conceivable as in the same manner as the electrode for cardiac stimulation and intracardiac electrocardiogram acquisition in the ICD device. However, in the case of the nerve stimulation electrode placed in the blood vessel, the SN ratio is small because the level of the electrocardiogram signal is small compared to the intracardiac electrocardiogram.
For the purpose of obtaining an electrocardiogram, it is desirable that the electrode interval is relatively large. However, it has been empirically found that it is effective that the electrode interval is about 5 mm in nerve stimulation. It is not easy to obtain suitable electrocardiograms.

(Third embodiment)
A third embodiment of the present invention will be described with reference to FIGS.
FIG. 16 is a schematic diagram showing the overall configuration of the nerve stimulation apparatus 201 according to the present embodiment. The nerve stimulation device 201 includes a stimulation generator 210 and a nerve stimulation electrode 220. The stimulus generator 210 generates a nerve stimulus signal. The nerve stimulation electrode 220 is placed in a blood vessel of a patient or the like.

The nerve stimulation electrode 220 is placed in a blood vessel of a patient or the like and applies a nerve stimulation signal generated by the stimulation generator 210 to a living tissue, thereby performing electrical stimulation to the nerve.
The nerve stimulation electrode 220 includes an indwelling unit 230 and a lead unit 221. The indwelling unit 230 is held in the blood vessel. The lead part 221 connects the indwelling part 230 and the stimulus generator 210.

The indwelling unit 230 includes a plurality of urging members 231 and a pair of stimulation electrodes 233A and 233B. The pair of stimulation electrodes 233A and 233B is attached to one of the biasing members 231.
Each urging member 231 has a rigidity that can maintain a certain shape against deformation of the indwelling blood vessel wall. Each urging member 231 can be suitably formed using a super elastic wire made of nickel titanium, for example. The surface of each urging member 231 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 member 231, a coating or a medicine for preventing thrombus may be further disposed.

  As shown in FIG. 16, the proximal end side of each biasing member 231 is connected to the distal end portion of the lead portion 221. As shown in FIG. 16, each urging member 231 is first radially outward of the lead portion 221 and distal to the tip end of the lead portion 221 (hereinafter referred to as “from”) as shown in FIG. 16 in a natural state where no external force is applied. , Referred to as “front”). Each biasing member 231 is then bundled close to the axis of the lead portion 221 while gradually curving.

  The pair of stimulation electrodes 233 </ b> A and 233 </ b> B is arranged at one longitudinal intermediate portion of the plurality of biasing members 231. The pair of stimulation electrodes 233A and 233B has a conductive electrode surface exposed on at least a part of the outer peripheral surface. As a material of the stimulation electrodes 233A and 233B, 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 233A located on the distal end side is a negative electrode, and the stimulation electrode 233B located on the proximal end side is a positive electrode. The stimulation electrodes 233A and 233B are connected to the stimulation generator 210 by wirings 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 221 has a known configuration including an insulating coating 222 and a connector 223, and is configured to be long and flexible. The wirings connected to the stimulation electrodes 233A and 233B pass through the coating provided on the urging member 231 and the insulating coating 222 of the lead portion 221 and are connected to the stimulation generator 210 via the connector 223.

A pair of detection electrodes (biological information acquisition electrodes) 224 and 225 are attached to the lead generator 221 on the stimulus generator 210 side. The detection electrode 224 includes a conductive electrode part 224a and an adhesive pad 224b. The detection electrode 225 includes a conductive electrode portion 225a and an adhesive pad 225b. Each electrode part 224a, 225a is connected to the stimulus generator 210 via a wiring (not shown) arranged in the lead part 221.
The adhesive pads 224b and 225b have a known configuration that can repeatedly adhere to and peel from the body surface of a patient or the like. The adhesive pads 224b and 225b are attached to support the lead part 221 and the electrode parts 224a and 225a on the body surface.
The pair of detection electrodes 224 and 225 are attached so as to be always positioned on the lead portion 221 without being separated from the lead portion 221 so that the lead portion 221 can be suitably supported.

FIG. 17 is a block diagram of the stimulus generator 210. The stimulus generation device 210 includes a stimulus generation unit 211, a biological information acquisition unit 212, and a control unit 213. The stimulus generator 211 generates a nerve stimulus signal. The biological information acquisition unit 212 acquires biological information such as a heart rate based on the potential change detected by the detection electrodes 224 and 225. The control unit 213 controls the stimulus generator 210 as a whole.
The biological information acquisition unit 212 acquires an electrocardiographic waveform based on the potential change of the living body detected by the detection electrodes 224 and 225. The biological information acquisition unit 212 acquires the heart rate of a patient or the like based on the RR interval of the electrocardiographic waveform.
The control unit 213 is connected to the stimulus generation unit 211 and the biological information acquisition unit 212. The control unit 213 instructs the stimulation generation unit 211 to generate a nerve stimulation signal when the heart rate received from the biological information acquisition unit 212 satisfies a predetermined condition. The mode of the nerve stimulation signal may be set in advance in the form of a program or the like in the control unit 213, or an interface unit for input may be provided in the stimulation generating device so that it can be set by an operation input by a user or a doctor May be set.
The stimulus generator 211 is connected to a power source (not shown) built in the stimulus generator 210. The stimulus generator 211 generates a nerve stimulus signal in response to an instruction from the controller 213. The generated neural stimulation signal is sent to the stimulation electrodes 233A and 233B through the lead portion 221 and applied to the living body.

The operation at the time of use of the nerve stimulation apparatus 201 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, the surgeon deforms each urging member 231 of the indwelling portion 230 into a linear shape along the axis of the lead portion 221 and then inserts it into a tubular member such as a sheath, and inserts the tubular member into an introducer or the like. To do. Next, the surgeon moves the distal end of the tubular member to an indwelling site close to the nerve that stimulates the tube. When the surgeon projects the indwelling portion 230 from the distal end of the tubular member, each biasing member 231 has a restoring force to the original shape, and thus comes into contact with the inner wall (blood vessel wall) of the blood vessel. As a result, the indwelling unit 230 is held in the blood vessel in a state where the stimulation electrodes 233A and 233B arranged on each biasing member 231 are in contact with the blood vessel wall.

When the position of the indwelling portion 230 is determined, the surgeon removes the introducer by removing or tearing the introducer. Thereby, the indwelling part 230 is indwelled in the predetermined position in a patient's blood vessel. The tubular member may or may not be removed.
As shown in FIG. 18, the pair of detection electrodes 224 and 225 is provided on the lead part 221 located outside the body in a state where the indwelling part 230 is indwelled at the predetermined position. The surgeon arranges the lead part 221 outside the body so as to lie over the body surface. The surgeon attaches the adhesive pad 224b of the detection electrode 224 and the adhesive pad 225b of the detection electrode 225 to the patient's skin. When the stimulus generator 210 is fixed to the patient's body surface, clothes, or the like with an adhesive tape or the like, placement of the entire nerve stimulator 201 is completed.

  During the placement of the nerve stimulation electrode 220, the heart rate is acquired and monitored at any time by the biological information acquisition unit 212 based on the information detected by the detection electrodes 224 and 225. When the heart rate satisfies a predetermined condition, the stimulation generation unit 211 generates a nerve stimulation signal according to a command from the control unit 213. The generated neural stimulation signal is applied to the stimulation electrodes 233A and 233B. The electrical stimulation applied to the tissue from the stimulation electrodes 233A and 233B stimulates the target nerve through the blood vessel wall to perform treatment.

  According to the nerve stimulation apparatus 201 according to the present embodiment, the detection electrodes 224 and 225 that detect information for obtaining biological information are provided on the lead part 221 that is located outside the body when the indwelling part 230 is placed. Therefore, a sufficient distance is maintained between the detection electrodes 224 and 225 and the stimulation electrodes 233A and 233B that perform nerve stimulation. As a result, noise due to nerve stimulation is suppressed from entering the detection electrodes 224 and 225, and accurate biological information can be acquired and appropriate treatment can be performed.

  Since the detection electrodes 224 and 225 are always provided on the lead portion 221, the wiring does not extend further from the lead portion. Therefore, the linear part outside the body is substantially only the lead part 221. As a result, the apparatus configuration is simplified, and the troublesomeness of the patient at the time of indwelling is reduced.

  Since the detection electrode 224 has an adhesive pad 224b and the detection electrode 225 has an adhesive pad 225b, the lead portion 221 can be fixed to the body surface by attaching the adhesive pad to the body surface such as skin. it can. As a result, the operator can simply place the indwelling and can stabilize the position of the lead part outside the body after the indwelling. In general, the deviation of the lead part outside the body is a cause of the deviation of the indwelling part 30 in the body. However, the nerve stimulation apparatus 201 according to the present embodiment also contributes to the certainty of treatment due to the above configuration.

  In the present embodiment, an example in which both of the pair of detection electrodes are located outside the body when the indwelling unit 230 is placed in the body is described. However, as shown in FIGS. 19 and 20, one electrode portion 224a of the detection electrode may be disposed on the indwelling portion 230 or on the lead portion 221 located in the body. However, the closer the electrode part 224a is to the stimulation electrodes 233A and 233B, the higher the probability that noise will enter during nerve stimulation. Is preferred.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIG. The difference between the present embodiment and the third embodiment is that a reference electrode is further provided as a biological information acquisition electrode. In the following description, the same components as those already described are denoted by the same reference numerals and redundant description is omitted.

  FIG. 21 is a schematic diagram showing the configuration of the nerve stimulation apparatus 251 according to the present embodiment. A reference electrode 252 is provided on the outer surface of the stimulus generator 210. The reference electrode 252 has an electrode part 252a and an adhesive part 252b. The electrode unit 252a is connected to the biological information acquisition unit 212 of the stimulus generator. The adhesive portion 252b can have the same configuration as the adhesive portions 224b and 225b.

When the nerve stimulating device 251 is placed, if the surgeon attaches the adhesive portion 252b to the patient's body surface, the stimulus generator 210 is fixed to the body surface together with the electrode portion 252a.
After placement of the nerve stimulator 251, an electrocardiographic waveform is acquired based on tripolar information obtained by adding the reference electrode 252 to the detection electrodes 224 and 225.

  Similar to the nerve stimulation apparatus 201 according to the first embodiment, the nerve stimulation apparatus 251 according to the present embodiment can acquire accurate biological information and perform appropriate treatment.

In addition, since the nerve stimulation apparatus 251 according to this embodiment includes the reference electrode 252, it can acquire an electrocardiographic waveform with three poles. As a result, the nerve stimulation apparatus 251 according to the present embodiment can reduce the influence of the fluctuation of the signal baseline due to noise or body movement mixed in the electrocardiogram signal by using a known correction method. The nerve stimulation apparatus 251 according to the present embodiment can further improve the accuracy of the acquired biological information.
Furthermore, in the nerve stimulation apparatus 251 according to the present embodiment, the reference electrode 252 is provided on the stimulation generator 210. Therefore, by fixing the reference electrode 252, the stimulus generator 210 can also be fixed, and the indwelling operation can be easily performed.

  In the present embodiment, the example in which the reference electrode is provided on the stimulus generator has been described. The position where the reference electrode is placed is not limited to this, and may be provided on the lead portion 221 or the placement portion 230. In general, since the bipolar electrode is installed at a position sandwiching from the upper right to the lower left with the heart as the center, a large signal level can be obtained, which is advantageous for heart rate measurement. In this case, it is desirable that the reference electrode be installed at a position where the distance from the other two poles on the upper left or lower right is equal to the heart. The effect of noise reduction can be expected even when lead wires are not routed at all at equal intervals.

  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 the above-described fourth embodiment, the example in which the reference electrode is provided on the stimulus generator has been described, but instead of this, one of the detection electrodes may be provided in the stimulus generator. If comprised in this way, even if it is the structure which is not provided with a reference | standard electrode, the electrode fixed to a body surface and a stimulus generator can be fixed by one operation.

  Further, by using a known snap button mechanism or the like, the detection electrode and the reference electrode may be configured to be detachable from the lead portion. At this time, if a plurality of snap button mechanisms such as detection electrodes or more are provided on the lead portion, the attachment positions of the detection electrodes and the like can be adjusted according to the patient or the like. Furthermore, if an adhesive pad having no electrode part is attached to a snap button mechanism to which no detection electrode or the like is attached, the lead part is fixed to the body surface in a more stable state.

  The preferred embodiments of the present invention have been described above, but the present 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.

  Each of the above embodiments provides a nerve stimulation device, a nerve stimulation system, and a tissue stimulation method that can perform vagus nerve stimulation and heart rate measurement with a simple configuration and can acquire an electrocardiographic signal more accurately. it can.

DESCRIPTION OF SYMBOLS 1 Neural stimulation system 11 1st stimulation electrode, stimulation electrode 12 2nd stimulation electrode, stimulation electrodes 13, 221 Lead part 14 1st electrocardiogram acquisition electrode, electrocardiogram acquisition electrode 15 2nd electrocardiogram acquisition electrode, electrocardiogram acquisition electrode 17 Heart rate measurement part 19 Stimulation signal generator 35, 40, 45, 50, 55, 60, 70 Neural stimulation system 72 Switching unit, switching unit 74 First switch, switching unit, switching unit 78 Second switch, switching unit, switching unit 90 Neural stimulation System 95 Neural stimulation system 96 Switch, switching unit, switching unit 110 Neural stimulation system 111 First switch, switching unit, switching unit 112 Second switch, switching unit, switching unit 201, 251 Neural stimulation device 210 Stimulation generator 220 Neural stimulation Electrodes 224, 225 Detection electrodes (biological information acquisition electrodes)
224b, 225b, 252b Adhesive part 233A, 233B Stimulation electrode 252 Reference electrode (biological information acquisition electrode)

Claims (9)

A lead portion disposed in the blood vessel;
A stimulation electrode having at least two electrodes;
An electrocardiogram acquisition electrode composed of at least two electrodes;
A stimulation signal generator for generating a stimulation signal;
A heart rate measurement unit for measuring a heart rate from the electrocardiogram acquisition electrode;
With
The nerve stimulation system, wherein the stimulation electrode and the electrocardiogram acquisition electrode are arranged on the same lead part. A lead portion disposed in the blood vessel;
A stimulation electrode composed of at least two electrodes;
A 1-pole ECG acquisition electrode;
A stimulation signal generator for generating a stimulation signal;
A heart rate measurement unit for measuring a heart rate from the electrocardiogram acquisition electrode;
Switching means connected to the stimulation electrode and switching the connection to the stimulation signal generation unit and the heart rate measurement unit;
With
The stimulation electrode and the electrocardiogram acquisition electrode are arranged on the same lead part,
When applying neural stimulation, the switching means performs switching so as to connect the stimulation electrode to the stimulation signal generator, and when acquiring an electrocardiogram, the switching means measures one of the stimulation electrodes as the heart rate. A neural stimulation system that switches to connect to one input / output of the unit.   The nerve stimulation system according to claim 1 or 2, wherein switching is performed so that the two electrodes of the stimulation electrode have the same potential when acquiring an electrocardiogram.   A stimulation electrode having at least two electrodes is used, an electrocardiogram acquisition electrode composed of at least two electrodes is used, a stimulation signal is generated by a stimulation signal generation unit, and a heart rate is measured from the electrocardiogram acquisition electrode by a heart rate measurement unit. A nerve stimulation method for measuring nerves and performing nerve stimulation by placing the stimulation electrode and the electrocardiogram acquisition electrode on the same lead portion disposed in a blood vessel. A nerve stimulation device that is placed in a living body and electrically stimulates nerves,
A stimulation electrode for applying the electrical stimulation to a nerve, and a nerve stimulation electrode having a lead portion having a first end connected to the stimulation electrode;
A stimulation generator connected to a second end of the lead portion and generating a nerve stimulation signal for applying the electrical stimulation;
Two or more biological information acquisition electrodes provided on the lead portion so that at least one is not separated from the lead portion;
A nerve stimulation device comprising:   The nerve stimulation apparatus according to claim 5, wherein the biological information acquisition electrode provided on the lead portion has an adhesive portion and can be adhesively fixed to the surface of the biological body.   The nerve stimulation apparatus according to claim 5 or 6, wherein one of the biological information acquisition electrodes is provided on the stimulation generator.   The nerve stimulation device according to claim 7, wherein the biological information acquisition electrode provided on the stimulation generator has an adhesive portion and can be adhesively fixed to the biological surface.   The nerve stimulation apparatus according to any one of claims 5 to 8, wherein three or more biological information acquisition electrodes are provided, and one of the biological information acquisition electrodes is set as a reference electrode from which an electrocardiographic waveform is acquired. .

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