Electrostimulator, electrostimulation system, electrostimulation method, and program

Abstract

To provide a technology for increasing the probability of improvement of cardiac asynchrony by a cardiac resynchronization therapy.SOLUTION: An electrostimulator includes: an electrode for giving electrostimulation to the ventricular muscle of the target heart to which electrostimulation is given in a cardiac resynchronization therapy; a cover covering at least a part of the target heart and the electrode; and an application circuit control part for controlling operation of an application circuit applying voltage or current to the electrode on the basis of information indicating timing at which stimulation is given to an optimum stimulus point being a position of the target heart where electrostimulation is given in the cardiac resynchronization therapy. Control by the application circuit control part controls the application circuit so that voltage or current is applied to the electrode disposed at the optimum stimulus point at the timing, and at least a part of the optimum stimulus point is covered with the cover.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an electrical stimulation device, an electrical stimulation system, an electrical stimulation method, and a program. Regarding. [Background technology]

[0002] Heart failure is a condition in which the heart is unable to pump enough blood to meet the body's needs. The number of patients with heart failure is estimated to be 1.2 million in Japan and 5 million in the United States.

[0003] Cardiac myocardium with heart failure exhibits a reduced ejection fraction due to enlarged end-diastolic volume and asynchronous cardiac contraction (hereafter referred to as "cardiac asynchrony"). Cardiac asynchrony is a pathological condition in which normal excitation propagation is disrupted by factors such as myocardial infarction or bundle branch block, resulting in a discrepancy in the timing of contractions between or within the ventricles, or in some parts of the ventricles not contracting. In the case of cardiac asynchrony, a discrepancy in the timing of contractions between or within the ventricles, or in some parts of the ventricles not contracting, can result in insufficient stroke volume. Therefore, people with cardiac asynchrony may develop heart failure.

[0004] Heart failure treatments include drug therapy and non-drug therapy, but drug therapy has been shown to have limitations. Therefore, cardiac resynchronization therapy (CRT) is sometimes performed to improve cardiac asynchrony (see Non-Patent Document 1). Cardiac resynchronization therapy is a treatment that synchronizes the contractions of failing myocardium by applying electrical stimulation to the myocardium.

[0005] Cardiac resynchronization therapy (CRT) has been reported to have a higher survival rate than drug therapy. CRT is performed, for example, by inserting a catheter electrode into the coronary vein. In this case, CRT applies a voltage to the catheter electrode, which electrically stimulates the ventricles to synchronize the contractions of the failing myocardium. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] JA Kirk, DA Kass, “Electromechanical dyssynchrony and resynchronization of the failing heart”, Circulation Research, 113 (2013) 765-776. Summary of the Invention [Problem to be solved by the invention]

[0007] However, with cardiac resynchronization therapy, which uses a catheter electrode inserted into the coronary veins, there have been cases where patients (non-responders) do not experience any therapeutic benefit (i.e., improvement in cardiac asynchrony) despite the implantation of the device. The following two reasons are thought to be the main reasons for the existence of non-responders. One reason is that the location of effective cardiac synchronous stimulation varies from patient to patient. The other reason is that the course of the coronary veins varies from patient to patient, limiting the placement of the stimulation electrode. As a result, the electrode cannot be placed in an effective location, making it impossible to deliver stimulation. This issue is not limited to humans, but is common to animals in general, including humans.

[0008] In view of the above circumstances, an object of the present invention is to provide a technique for increasing the probability of improving cardiac asynchrony through cardiac resynchronization therapy. [Means for solving the problem]

[0009] One aspect of the present invention is an electrical stimulation device comprising: electrodes that apply electrical stimulation to ventricular muscles of a target heart, which is a target heart to which electrical stimulation is to be applied in cardiac resynchronization therapy; a cover that covers at least a portion of the target heart and the electrodes; and an application circuit control unit that controls the operation of an application circuit that applies a voltage or current to the electrodes based on timing information that indicates the timing of applying stimulation to an optimal stimulation point, which is a position of the target heart and an optimal stimulation point for applying electrical stimulation in cardiac resynchronization therapy, wherein the control by the application circuit control unit controls the application circuit so that a voltage or current is applied to the electrode positioned at the optimal stimulation point at the timing indicated by the timing information, and at least a portion of the optimal stimulation point is covered by the cover. [Effects of the Invention]

[0010] The present invention makes it possible to provide a technique that increases the probability of improving cardiac asynchrony through cardiac resynchronization therapy. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram showing an example of the configuration of an electrical stimulation system 100 according to an embodiment. [Figure 2] FIG. 3 is an explanatory diagram illustrating the wiring of the conductor wire 30 in the embodiment. [Figure 3] 3 is an explanatory diagram illustrating the positional relationship between the conducting wire 30, the electrode 40, and the cover 50 and the target heart in the embodiment. FIG. [Figure 4] FIG. 1 is a diagram showing an example of the functional configuration of a stimulus control device 10 according to an embodiment. [Figure 5] FIG. 2 is a diagram showing an example of the functional configuration of an internal control device 17 and an external control device 18 in the embodiment. [Figure 6] FIG. 2 is a diagram showing an example of the functional configuration of a control unit 11 in the embodiment. [Figure 7] FIG. 2 is a diagram showing an example of the functional configuration of a heart simulator 2 according to an embodiment. [Figure 8] 4 is a flowchart showing an example of a flow of processing executed by the electrical stimulation device 1 according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] (First embodiment) FIG. 1 is a diagram showing an example of the configuration of an electrical stimulation system 100 according to an embodiment. The electrical stimulation system 100 includes an electrical stimulation device 1 and a cardiac simulator 2. The cardiac simulator 2 executes a simulation to acquire information (hereinafter referred to as "optimal stimulation point information") indicating the location of an optimal stimulation point (hereinafter referred to as "optimal stimulation point") for resynchronization of a target heart stimulated by the electrical stimulation device 1. The cardiac simulator 2 also acquires information (hereinafter referred to as "timing information") indicating the timing of applying stimulation to the optimal stimulation point. The target heart refers to a heart 9 that is the target of stimulation by the electrical stimulation device 1. Stimulating specifically means applying a voltage or current. Based on the results of the simulation by the cardiac simulator 2, the electrical stimulation device 1 applies electrical stimulation to the myocardium of the target heart via electrodes attached to the surface of the target heart.

[0013] The cardiac simulator 2 acquires optimal stimulation point information and timing information by executing, for example, a program that calculates optimal stimulation points and stimulation timing (hereinafter referred to as the "optimal stimulation point calculation program"). The optimal stimulation point calculation program is a method for calculating optimal stimulation points and stimulation timing using a numerical calculation method such as the finite element method. Execution of the optimal stimulation point calculation program is an example of execution of a simulation. That is, the optimal stimulation point calculation program is an example of a simulation that calculates optimal stimulation points and stimulation timing using a numerical calculation method such as the finite element method. Therefore, the electrical stimulation device 1 and the electrical stimulation system 100 including the electrical stimulation device 1 are devices used in cardiac resynchronization therapy (CRT). Note that cardiac resynchronization therapy is a treatment method that synchronizes the contractions of failing myocardium by applying electrical stimulation to the myocardium via the cardiac surface. For ease of explanation, the electrical stimulation system 100 will be described below using an example in which the cardiac simulator 2 acquires optimal stimulation point information and timing information.

[0014] The optimal stimulation point calculation program may be a simulator program for an individual patient, based on the medical data of each patient. A patient refers to a person who has a target heart. "Individual patient" means for each patient.

[0015] The optimal stimulation point calculation program is, for example, a program for a multiphysics simulator that analyzes both electrical and mechanical phenomena of the heart.

[0016] In the optimal stimulation point calculation program, when evaluating electrode placement, for example, both the electrical and mechanical phenomena of the heart may be analyzed using Δdp / dtmat. Δdp / dtmat is the change in the maximum left ventricular pressure gradient before and after treatment. The evaluation of electrode placement means the calculation of the optimal stimulation point. In other words, the evaluation of electrode placement means the acquisition of optimal stimulation point information.

[0017] The electrical stimulation device 1 includes a stimulation control device 10, an application circuit 20, conductive wires 30, electrodes 40, and a cover 50.

[0018] The stimulation control device 10 acquires the simulation results of the cardiac simulator 2 and controls the operation of the application circuit 20 based on the acquired simulation results. An example of the hardware configuration of the stimulation control device 10 will be described in detail later. Specifically, the stimulation control device 10 controls the operation of the application circuit 20 so as to apply a voltage or current to an electrode 40 (hereinafter referred to as an "optimal electrode") located at a position where electrical stimulation can be applied to an optimal stimulation point. Controlling the operation of the application circuit 20 so as to apply a voltage or current to the optimal electrode means controlling the on / off of each switch provided in the application circuit 20 so as to pass a voltage or current through a conductor connected to the optimal electrode.

[0019] The application circuit 20 is a circuit connected to the conductor 30. Therefore, the application circuit 20 includes conductors (hereinafter referred to as "conductors 200") that constitute the circuit. The application circuit 20 includes not only the conductors 200, but also a switch 201, such as a semiconductor switch, that operates in response to control from the stimulus control device 10 and controls the application of a voltage or current to the conductor 30, and a power supply 202. The switch 201 and the power supply 202 are connected to the conductor 200. The power supply 202 is, for example, a battery. The power supply 202 may be a device that is connected to an external power source, such as a commercial power source, and outputs power supplied by the external power source. The application circuit 20 controls the voltage or current applied to the conductor 30 by controlling the on / off of each switch 201 by the stimulus control device 10.

[0020] The conductor 30 is a conductor connected to the electrode 40. The voltage or current applied by the application circuit 20 is applied to the electrode 40 via the conductor 30. It is desirable that the conductor 30 be flexible and deformable. The more flexible and deformable the conductor 30 is, the more it can reduce the force applied to the connection point between the electrode 40 and the conductor 30 due to the pulsation of the target heart. Therefore, the more flexible and deformable the conductor 30 is, the more it can suppress deterioration of the conductor 30 and the electrode 40. The wiring of the conductor 30 will be described in detail below.

[0021] The electrode 40 is an electrode. The electrode 40 is attached to the cardiac surface of the target heart. The electrode 40 applies a voltage applied via the conductor 30 to the target heart to which it is attached. The electrode 40 may be made of any material and may have any shape as long as it is capable of electrically stimulating the ventricular muscle via the cardiac surface of the target heart. At least a portion of the electrode 40 is placed at an optimal stimulation point, and a voltage or current is applied to the electrode placed at the optimal stimulation point via the conductor 30 by the application circuit 20.

[0022] The electrode 40 is, for example, a convex-shaped bioelectrode that can contact the myocardial wall. The bioelectrode may be, for example, a button-type electrode, a plate-type electrode, a needle-type electrode, a wire-type electrode, a mesh-type electrode, or a coil-type electrode. The shape of the electrode 40 may also be a spike, a screw, a ring, or a wire. However, in consideration of the stability of the connection with the ventricular wall and the combination with support, it is desirable that the electrode 40 be a button-type electrode.

[0023] The electrode 40 is preferably formed from conductive fibers. When the electrode 40 is made of conductive fibers, the occurrence of physical effects on the living body, such as cell rejection and inflammatory reactions, is suppressed. The material from which the conductive fibers are formed may be any conductive material. An example of the conductive material is platinum. The conductive material is not limited to platinum, but may also be a platinum-iridium alloy, titanium, platinum, carbon, cobalt, or nickel.

[0024] The conductive material may be a conductive polymer. In such a case, the electrode 40 follows the contraction of the myocardium, thereby reducing friction between the electrode 40 and the target heart. Therefore, such an electrode 40 can suppress the occurrence of tissue inflammation. Furthermore, such an electrode 40 can suppress the increase in electrical resistance associated with tissue inflammation.

[0025] It is desirable that at least a portion of the conductive material forming electrode 40 is a hydrophilic conductive material, because hydrophilic conductive materials have a better affinity with biological tissue than non-hydrophilic conductive materials, cause less inflammation at the contact point with the living body, and can maintain stable contact.

[0026] At least one of the electrodes 40 is preferably positioned in the left ventricular region of the target heart. The electrodes 40 are preferably positioned in close contact with the myocardial wall of the target heart. The closer the electrodes 40 are to the myocardial wall of the target heart, the more efficiently the electrical stimulation device 1 can stimulate the myocardium. The position of the electrodes 40 will be described in detail below.

[0027] The cover 50 is attached to the target heart and covers at least a portion of the target heart and the electrode 40. That is, the electrode 40 is located inside the cover 50. Note that the inside of the cover 50 means the epicardial side of the target heart.

[0028] The covering 50 may be of any material as long as it can cover a portion of the target heart and the electrode 40. The covering 50 may be, for example, a net, mesh, string-like band, or sheet-like patch woven from various fibers. The covering 50 may be, for example, a mesh made of highly biocompatible polyester or nylon fibers that has little elasticity so that it can be permanently implanted around the heart and is sometimes used to suppress ventricular dilation in heart failure.

[0029] The fibers forming the cover 50 are not limited to highly biocompatible polyester or nylon fibers, but may also be made of conductive fibers. The conductive fibers do not need to be used for the entire cover 50, but may be used for only a portion of the cover 50. When the fibers forming the cover 50 are conductive fibers, the cover 50 is made of conductive fibers, which suppresses the occurrence of physical effects on the living body, such as cell rejection and inflammatory reactions, and enables electrical stimulation, shielding, and recording of biopotentials.

[0030] <About the wiring of conductor 30> It is desirable that the conductor 30 be arranged outside the covering 50. It is also desirable that the conductor 30 be in contact with the covering 50. It is also desirable that the conductor 30 be separable from the covering 50. By arranging the conductor 30 outside the covering 50, when deterioration such as aging occurs in the conductor 30 or the covering 50, it is possible to replace only the conductor 30 or only the covering 50. Furthermore, by arranging the conductor 30 outside the covering 50, circulation in the coronary blood vessels is less likely to be obstructed by the conductor 30. In other words, obstruction of blood flow in the coronary artery and vein due to the conductor 30 is avoided.

[0031] Furthermore, the longitudinal direction of the conductor 30 is preferably oriented from the electrode 40 toward the apex of the target heart (i.e., along the meridian). In other words, the conductor 30 is preferably wired in a manner that is pulled up from the apex of the heart.

[0032] By wiring in this manner, the conductor 30 can change shape in accordance with the beating of the target heart. Therefore, by wiring in this manner, excessive force is not applied to the connection point between the conductor 30 and the electrode 40 even when the target heart moves, thereby improving the durability of the electrical stimulation device 1. Furthermore, the smaller the force applied to the connection point, the more stable the contact between the electrode 40 and the target heart can be. Furthermore, because the contact between the electrode 40 and the target heart is stable, the occurrence of physical effects on the living body, such as cell rejection and inflammatory reactions, is suppressed.

[0033] Furthermore, the smaller the force applied to the connection point, the smaller the burden on the attachment point of the electrode 40, which also reduces the burden on the target heart. Furthermore, by wiring in this manner, the lead wire 30 can move in accordance with the beating of the target heart even when the target heart moves, so friction between the lead wire 30 and the target heart is small, reducing the burden on the target heart and deterioration of the lead wire 30. Because the burden on the target heart is reduced, the occurrence of physical effects on the living body, such as cell rejection and inflammatory reactions, is suppressed.

[0034] The wiring of such conductors 30 is illustrated in FIG. 2 below. FIG. 2 is an explanatory diagram illustrating the wiring of the conductor wire 30 in the embodiment. FIG. 2 includes images A1-1, A1-2, A2-1, and A2-2. The images on the left side of FIG. 2 (i.e., images A1-1 and A1-2) are explanatory diagrams illustrating the effect that occurs when a rigid conductor 30 is used and is not fixed to the cover 50. Image A1-1 is a front view, and image A1-2 is a side view. Images A1-1 and A1-2 show that the electrode 40 repeatedly rubs against the tissue of the target heart (heart 9) due to mechanical vibration caused by cardiac contraction. In such cases, tissue fibrosis progresses. Furthermore, deterioration of implants such as the conductor 30, electrode 40, and cover 50 also accelerates.

[0035] The images on the right side of FIG. 2 (i.e., images A2-1 and A2-2) are explanatory diagrams illustrating the effect that occurs when a flexible conductor 30 is used and fixed to the cover 50 in the vertical direction (along the meridian). Image A2-1 is a front view, and image A2-2 is a side view. Images A2-1 and A2-2 show that the electrode 40 is in stable contact with the tissue of the target heart (heart 9) and does not rub against it. In this case, tissue fibrosis and deterioration of implants such as the conductor 30, electrode 40, and cover 50 are suppressed.

[0036] <Position of electrode 40> The electrode 40 does not need to be located in a vein. In cardiac resynchronization therapy (hereinafter referred to as "therapy 0"), which is performed using a catheter electrode inserted into a coronary vein, the electrode needs to be located in a vein. However, in cardiac resynchronization therapy (hereinafter referred to as "therapy 1") performed by the electrical stimulation device 1, there is no such restriction because the electrode can be attached to the surface of the target heart without necessarily inserting a catheter electrode into the coronary vein. Therefore, the applied voltage or current can be reduced compared to therapy 0, reducing the burden on the target heart. Also, power consumption can be reduced.

[0037] Fig. 3 is an explanatory diagram illustrating the positional relationship between the conductor 30, electrode 40, and covering 50 and the target heart in an embodiment. In Fig. 3, the wire lead is an example of the conductor 30, the bioelectrode is an example of the electrode 40, and the mesh net is an example of the covering 50. Note that in Fig. 3, for the purpose of explaining the positional relationship, the wire lead, bioelectrode, and mesh net are shown as an example of a combination of the conductor 30, electrode 40, and covering 50, but the contents of the explanation in Fig. 3 are not limited to this combination and are applicable to other combinations, with similar effects being achieved.

[0038] 3 shows an example of the results of viewing the conductor 30, electrode 40, and cover 50 in relation to the target heart from two directions. Image A3 shows the results of viewing the conductor 30, electrode 40, and cover 50 in relation to the target heart from the front, and image A4 shows the results of viewing the conductor 30, electrode 40, and cover 50 in relation to the target heart in image A1 from the side.

[0039] FIG. 3 shows that the target heart is covered with a mesh net and the wire lead is located outside the mesh net. The fact that the wire lead is located outside the mesh net is particularly clearly shown in FIG. A4. FIG. A4 also shows that the wire lead is not in contact with the coronary artery or vein because it is located outside the mesh net. Because the wire lead is not in contact with the coronary artery or vein, obstruction of coronary artery or vein blood flow by the wire lead is avoided. FIG. 3 also shows that an example of the location of the bioelectrode (electrode 40) is on the epicardial side of the left ventricular wall of the target heart.

[0040] 4 is a diagram showing an example of the functional configuration of the stimulus control device 10 in an embodiment. The stimulus control device 10 includes a control unit 11 having a processor 91 such as a CPU (Central Processing Unit) and a memory 92 connected by a bus, and executes a program. By executing the program, the stimulus control device 10 functions as a device including the control unit 11, an input unit 12, a communication unit 13, a storage unit 14, an output unit 15, and a connection circuit 16. More specifically, the processor 91 reads a program stored in the storage unit 14 and stores the read program in the memory 92. By the processor 91 executing the program stored in the memory 92, the stimulus control device 10 functions as a device including the control unit 11, the input unit 12, the communication unit 13, the storage unit 14, the output unit 15, and the connection circuit 16.

[0041] The control unit 11 controls the operation of various functional units included in the stimulation control device 10. The control unit 11 generates a control signal for controlling the operation of the application circuit 20 based on timing information acquired by the heart simulator 2, for example.

[0042] The input unit 12 includes input devices such as a mouse, a keyboard, and a touch panel. The input unit 12 may be configured as an interface that connects these input devices to the stimulus control device 10. The input unit 12 accepts input of various information to the stimulus control device 10. For example, timing information is input to the input unit 12.

[0043] The communication unit 13 includes a communication interface for connecting the stimulation control device 10 to the heart simulator 2. The communication unit 13 communicates with the heart simulator 2 via wired or wireless communication. The communication unit 13 acquires timing information acquired by the heart simulator 2 through communication with the heart simulator 2.

[0044] The memory unit 14 is configured using a non-transitory computer-readable storage medium device such as a magnetic hard disk drive or a semiconductor storage device. The memory unit 14 stores various information related to the stimulation control device 10. The memory unit 14 stores, for example, timing information input via the input unit 12 or the communication unit 13. The memory unit 14 stores, for example, a program (hereinafter referred to as an "optimal control signal generation program") that generates a control signal (hereinafter referred to as an "optimal control signal") that controls the operation of the application circuit 20 in accordance with the timing information, which is a control signal corresponding to the timing information. The optimal control signal is a control signal that controls the operation of the application circuit 20 so as to apply a voltage or current to the optimal electrode.

[0045] The output unit 15 outputs various types of information. The output unit 15 includes a display device such as a Cathode Ray Tube display, a liquid crystal display, or an organic EL (Electro-Luminescence) display. The output unit 15 may be configured as an interface that connects these display devices to the stimulus control device 10. The output unit 15 outputs information input to the input unit 12, for example.

[0046] The connection circuit 16 is a circuit connected to the application circuit 20 and transmits an optimum control signal to the application circuit 20 .

[0047] The stimulation control device 10 may be configured with two control devices: an internal control device 17 and an external control device 18. 5 is a diagram showing an example of the functional configuration of the internal control device 17 and the external control device 18 in the embodiment. The internal control device 17 is a device that is implanted subcutaneously. The external control device 18 is located outside the human body. The internal control device 17 and the external control device 18 can communicate with each other using a built-in wireless communication interface. Various settings of the internal control device 17 are performed wirelessly by the external control device 18.

[0048] The internal control device 17 includes a control unit 11, an input unit 12, an output unit 15, a storage unit 14, and a first communication unit 101, which are connected by a bus. The first communication unit 101 includes a communication interface for connecting the internal control device 17 to an external control device 18. The first communication unit 101 communicates with the external control device 18 wirelessly.

[0049] The external control device 18 includes a sub-controller 19, a connection circuit 16, and a second communication unit 102, all connected via a bus. The sub-controller 19 includes a processor 95 such as a CPU and a memory 96, and executes a program. The sub-controller 19 controls the operation of the external control device 18 by executing the program. The second communication unit 102 includes a communication interface for connecting the external control device 18 to the internal control device 17. The second communication unit 102 communicates with the internal control device 17 wirelessly.

[0050] The sub-control unit 19 performs various settings related to the operation of the internal control device 17 via the first communication unit 101 and the second communication unit 102. Specifically, the sub-control unit 19 records values related to the control of the operation of the internal control device 17 in the memory unit 14 of the internal control device 17 via the first communication unit 101 and the second communication unit 102. The sub-control unit 19 changes setting values related to the internal control device 17, such as the operation mode, output, input, and threshold values of the internal control device 17, via the first communication unit 101 and the second communication unit 102. The sub-control unit 19 checks the status and operation of the device, for example, by viewing the operation log of the internal control device 17 via the first communication unit 101 and the second communication unit 102. The first communication unit 101 and the second communication unit 102 do not communicate constantly but intermittently. During the period when first communication unit 101 and second communication unit 102 are not communicating, internal control unit 17 operates independently of sub-control unit 19 without being controlled by sub-control unit 19. For example, internal control unit 17 performs electrical stimulation of the CRT.

[0051] 6 is a diagram showing an example of the functional configuration of the control unit 11 in the embodiment. The control unit 11 includes a timing information acquisition unit 111 and an application circuit control unit 112.

[0052] The timing information acquisition unit 111 acquires timing information acquired by the heart simulator 2 via the communication unit 13. When timing information is input to the input unit 12, the timing information acquisition unit 111 may acquire the timing information input to the input unit 12. Furthermore, when timing information is stored in the storage unit 14, the timing information acquisition unit 111 may read out the timing information from the storage unit 14.

[0053] The application circuit control unit 112 controls the operation of the application circuit 20. The application circuit control unit 112 controls the operation of the application circuit 20 by generating an optimal control signal according to timing information, for example, by executing an optimal control signal generation program stored in the storage unit 14. The optimal control signal generated by the application circuit control unit 112 is transmitted to the application circuit 20 via the connection circuit 16. The optimal control signal generated by the application circuit control unit 112 is transmitted to the application circuit 20 via the connection circuit 16, and the application circuit control unit 112 controls the operation of the application circuit 20. Specifically, the control by the application circuit control unit 112 is to control the application circuit 20 so that a voltage or current is applied to the electrode 40 placed at the optimal stimulation point.

[0054] 7 is a diagram showing an example of the functional configuration of a heart simulator 2 in an embodiment. The heart simulator 2 includes a control unit 21 having a processor 93 such as a CPU and a memory 94 connected by a bus, and executes a program. By executing the program, the heart simulator 2 functions as a device including the control unit 21, an input unit 22, a communication unit 23, a storage unit 24, and an output unit 25. More specifically, the processor 93 reads a program stored in the storage unit 24 and stores the read program in the memory 94. By the processor 93 executing the program stored in the memory 94, the heart simulator 2 functions as a device including the control unit 21, the input unit 22, the communication unit 23, the storage unit 24, and the output unit 25.

[0055] The control unit 21 controls the operation of various functional units included in the heart simulator 2. The control unit 21 calculates the position of the optimal stimulation point by, for example, executing an optimal stimulation point calculation program. The control unit 21 acquires information indicating the calculated position of the optimal stimulation point as optimal stimulation point information. The control unit 21 also acquires timing information by, for example, executing the optimal stimulation point calculation program.

[0056] The input unit 22 includes input devices such as a mouse, keyboard, and touch panel. The input unit 22 may be configured as an interface that connects these input devices to the cardiac simulator 2. The input unit 22 accepts input of various information to the cardiac simulator 2. For example, information required for executing an optimal stimulation point calculation program is input to the input unit 22.

[0057] The communication unit 23 includes a communication interface for connecting the heart simulator 2 to the stimulation control device 10. The communication unit 23 communicates with the stimulation control device 10 via wire or wirelessly. The communication unit 23 transmits timing information acquired by the heart simulator 2 to the stimulation control device 10 through communication with the stimulation control device 10.

[0058] The storage unit 24 is configured using a non-transitory computer-readable storage medium device such as a magnetic hard disk drive or a semiconductor storage device. The storage unit 24 stores various information related to the cardiac simulator 2. The storage unit 24 stores, for example, information input via the input unit 22. The storage unit 24 stores, for example, an optimal stimulation point calculation program.

[0059] The output unit 25 outputs various types of information. The output unit 25 includes a display device such as a Cathode Ray Tube display, a liquid crystal display, or an organic EL display. The output unit 25 may be configured as an interface that connects these display devices to the cardiac simulator 2. The output unit 25 outputs, for example, information input to the input unit 22. The output unit 25 may display, for example, the position of the optimal stimulation point indicated by the acquired optimal stimulation point information.

[0060] FIG. 8 is a flowchart showing an example of a flow of processing executed by the electrical stimulation device 1 according to the embodiment. The timing information acquisition unit 111 acquires timing information (step S101). Next, the application circuit control unit 112 generates an optimal control signal according to the timing information (step S102). The generated optimal control signal controls the operation of the application circuit 20, and as a result, a voltage or current is applied to the electrode 40 located at the optimal stimulation point indicated by the optimal stimulation point information at the timing indicated by the timing information. In this way, electrical stimulation is applied to the optimal stimulation point.

[0061] As described above, the electrical stimulation device 1 uses the cover 50 to apply electrical stimulation to the target heart, making it possible to place the electrode 40 at any position on the left ventricular free wall. This increases the probability of converting patients who were non-responders to therapy 0 into responders. This also means that the therapy is effective for patients who were responders to therapy 0, further improving their condition.

[0062] The electrical stimulation device 1 in this embodiment configured in this manner can stimulate the location of effective cardiac synchronous stimulation obtained by the cardiac simulator 2 with the electrodes 40, which are not limited in their placement location on the cardiac surface. Therefore, the electrical stimulation device 1 in this embodiment can improve cardiac asynchrony through cardiac resynchronization therapy with a higher probability than devices that perform therapy 0.

[0063] The electrical stimulation system 100 of the embodiment also includes such an electrical stimulation device 1, and therefore can improve cardiac asynchrony through cardiac resynchronization therapy with a higher probability than a device that performs therapy 0.

[0064] In addition, the electrical stimulation system 100 of the embodiment is equipped with a cardiac simulator 2 that executes an optimal stimulation point calculation program, allowing a user of the electrical stimulation system 100, such as a medical professional, to place the electrode 40 at any position on the left ventricular free wall of the heart 9 using the cover 50.

[0065] Experiments using the optimal stimulation point calculation program have shown that two electrodes on the left ventricular free wall sometimes produce better results than the conventional method of using one right ventricle electrode and one left ventricle (coronary vessel) electrode. This is not because the results of the optimal stimulation point calculation program are inaccurate, but because it has been medically proven that the program produces more appropriate results than previously known. However, conventional techniques make it difficult to attach electrodes, making it impossible to achieve two electrodes on the left ventricular free wall. On the other hand, the electrical stimulation system 100 includes a cover 50, allowing the user of the electrical stimulation system 100, such as a medical professional, to position the two electrodes on the left ventricular free wall.

[0066] (Variation) Note that power supply 202 may be a device that outputs power supplied wirelessly, such as by microwaves, as a voltage or current (i.e., a device that converts between an electromagnetic field and a voltage or current). In such a case, power supply 202 is not a battery, so there is less chance of a power shortage occurring during CRT operation. Furthermore, in such a case, power supply 202 is not connected to a commercial power source, so the patient has greater freedom of movement than when power supply 202 is a commercial power source.

[0067] It is desirable that the electrodes 40 be at least bipolar (i.e., two). If the electrodes are bipolar, controlling the phase of the voltage or current applied to one pole and the other pole increases the degree of freedom in adjusting the position and timing of applying electrical stimulation due to interference of the voltage or current.

[0068] The electrodes 40 may be placed in advance at each of a plurality of positions that are candidates for the optimal stimulation point, or may be placed by the user based on the results of a simulation by the cardiac simulator 2. In this way, at least a portion of the electrode 40 attached to the target heart is placed at the optimal stimulation point. Furthermore, the electrode 40 is covered by the cover 50, and at least a portion of the electrode 40 is placed at the optimal stimulation point, so that at least a portion of the optimal stimulation point is covered by the cover 50.

[0069] The cardiac simulator 2 may perform comprehensive optimization of the placement of the electrodes 40 on the right ventricular wall and the left ventricular free wall and the timing of applying electrical stimulation by executing an optimal stimulation point calculation program. Specifically, comprehensive optimization means maximizing Δdp / dtmat.

[0070] Each of the electrical stimulation device 1, the heart simulator 2, and the electrical stimulation system 100 may be implemented using a plurality of information processing devices communicably connected via a network. In this case, each functional unit included in each of the electrical stimulation device 1, the heart simulator 2, and the electrical stimulation system 100 may be distributed and implemented among the plurality of information processing devices.

[0071] All or part of the functions of the electrical stimulation device 1, the cardiac simulator 2, or the electrical stimulation system 100 may be realized using hardware such as an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field Programmable Gate Array). The program may be recorded on a computer-readable recording medium. Examples of the computer-readable recording medium include portable media such as a flexible disk, a magneto-optical disk, a ROM, and a CD-ROM, and storage devices such as a hard disk built into a computer system. The program may be transmitted via a telecommunications line.

[0072] Although an embodiment of the present invention has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and includes designs within the scope of the gist of the present invention. [Explanation of symbols]

[0073] 100...electrical stimulation system, 1...electrical stimulation device, 2...cardiac simulator, 10...stimulation control device, 20...application circuit, 200...conductor, 201...switch, 202...power supply, 30...conductor, 40...electrode, 50...cover, 11...control unit, 12...input unit, 13...communication unit, 14...memory unit, 15...output unit, 16...connection circuit, 17...internal control device, 18...external control device, 19...sub-control unit, 101...first communication unit, 102...second communication unit, 111...timing information acquisition unit, 112...application circuit control unit, 21...control unit, 22...input unit, 23...communication unit, 24...memory unit, 25...output unit, 9...heart, 91...processor, 92...memory, 93...processor, 94...memory, 95...Processor, 96...Memory

Claims

1. an electrode for applying electrical stimulation to a ventricular muscle of a target heart, which is a target heart to be electrically stimulated in cardiac resynchronization therapy; a cover covering at least a portion of the target heart and the electrodes; an application circuit control unit that controls the operation of an application circuit that applies a voltage or current to the electrodes based on timing information indicating a timing to apply a stimulus to an optimal stimulation point, which is a position of the target heart and is an optimal stimulation point for applying electrical stimulation in cardiac resynchronization therapy; Equipped with the control by the application circuit control unit controls the application circuit so that a voltage or a current is applied to the electrode placed at the optimal stimulation point at a timing indicated by the timing information; At least a part of the optimal stimulation point is covered by the cover. Electrical stimulation device.

2. At least one of the electrodes is positioned in a left ventricular region of the target heart. The electrical stimulation device according to claim 1 .

3. Conductors connected to the electrodes are disposed on the outside of the cover. The electrical stimulation device according to claim 1 .

4. Conductors connected to the electrodes are disposed on the outside of the cover. The electrical stimulation device according to claim 2 .

5. The longitudinal direction of the conductor is directed from the electrode toward the apex of the target heart. The electrical stimulation device according to claim 3 .

6. The longitudinal direction of the conductor is directed from the electrode toward the apex of the target heart. The electrical stimulation device according to claim 4 .

7. At least a portion of the electrode is formed from a hydrophilic conductive material. The electrical stimulation device according to claim 1 .

8. At least a portion of the electrode is formed from a hydrophilic conductive material. The electrical stimulation device according to claim 2 .

9. At least a portion of the electrode is formed from a hydrophilic conductive material. The electrical stimulation device according to claim 3 .

10. At least a portion of the electrode is formed from a hydrophilic conductive material. The electrical stimulation device according to claim 4.

11. At least a portion of the electrode is formed from a hydrophilic conductive material. The electrical stimulation device according to claim 6.

12. At least a portion of the electrode is formed from a hydrophilic conductive material. The electrical stimulation device according to claim 5 .

13. an electrical stimulation device comprising: electrodes that apply electrical stimulation to ventricular muscles of a target heart, the target heart being the heart to which electrical stimulation is to be applied in cardiac resynchronization therapy; a cover that covers at least a part of the target heart and the electrodes; and an application circuit control unit that controls the operation of an application circuit that applies a voltage or current to the electrodes based on timing information that indicates a timing to apply stimulation to an optimal stimulation point, which is a position of the target heart and is an optimal stimulation point to which electrical stimulation is to be applied in cardiac resynchronization therapy, wherein the control by the application circuit control unit controls the application circuit so that a voltage or current is applied to the electrode placed at the optimal stimulation point at the timing indicated by the timing information, and at least a part of the optimal stimulation point is covered by the cover; a cardiac simulator that acquires information indicating the position of the optimal stimulation point and the timing information by executing a simulation to calculate the optimal stimulation point and the timing; An electrical stimulation system comprising:

14. The simulation is a program that obtains the optimal stimulation point and the timing information using a finite element method.

14. The electrical stimulation system of claim 13.

15. The simulation is a simulator program for an individual patient having the target heart, the simulator program being based on medical data of each patient.

14. The electrical stimulation system of claim 13.

16. The simulation is a multiphysics simulator program that analyzes both electrical and mechanical phenomena of the heart.

14. The electrical stimulation system of claim 13.

17. In the simulation, when evaluating the electrode placement, analysis of both electrical and mechanical phenomena of the heart is performed using the change in the maximum left ventricular pressure gradient before and after treatment.

14. The electrical stimulation system of claim 13.

18. the cardiac simulator performs comprehensive optimization of the placement and timing of the electrodes on the right ventricular wall and the left ventricular free wall by executing the simulation; 14. The electrical stimulation system of claim 13.

19. an application circuit control unit that controls operation of an application circuit that applies a voltage or current to the electrode based on timing information indicating a timing to apply stimulation to an optimal stimulation point, which is a position of the target heart and is an optimal stimulation point for applying electrical stimulation in cardiac resynchronization therapy; a control step in which the application circuit control unit controls the application circuit so that a voltage or a current is applied to the electrode placed at the optimal stimulation point; An electrical stimulation method comprising:

20. A program for causing a computer to function as the electrical stimulation device according to any one of claims 1 to 12.

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