Implantable Electroacupuncture System for Treating Cardiovascular Disease

• US 20150231030A1
• Filed: 03/26/2015
• Published: 08/20/2015
• Est. Priority Date: 09/23/2011
• Status: Active Grant

• Current Assignee: Valencia Bioscience, Inc.
• Original Assignee: Valencia Technologies Corporation
• Inventors: Greiner, Jeffrey H., Peterson, David K. L., Thenuwara, Chuladatta
• Granted Patent: US 9,452,104 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61H 2201/01 Constructive details
• CPC Class Codes: A61H 39/00 Devices for locating or stimulating specific reflex points of the body for physical therapy, e.g. acupuncture chiropodists' instruments A61B17/54; for radiation therapy A61N5/0619
• CPC Class Codes: A61H 39/002 Using electric currents electrotherapy A61N1/32
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362
• CPC Class Codes: A61N 1/36117 for treating hypertension
• CPC Class Codes: A61N 1/36125 Details of circuitry or electric components
• CPC Class Codes: A61N 1/36153 Voltage A61N1/3616 takes precedence
• CPC Class Codes: A61N 1/36157 Current A61N1/3616 takes precedence
• CPC Class Codes: A61N 1/36175 Pulse width or duty cycle
• CPC Class Codes: A61N 1/37205 Microstimulators, e.g. implantable through a cannula
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators
• CPC Class Codes: A61N 1/3782 producing a voltage above the power source level
• CPC Class Codes: A61N 1/3787 from an external energy source
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

An Implantable ElectroAcupuncture Device (IEAD) treats cardiovascular disease through application of stimulation pulses applied at at least one of acupoints EX-HN1, BL14, HT7, HT5, PC6, ST36, LI11, LU7, and LU2. The IEAD comprises an implantable, coin-sized, self-contained, leadless electroacupuncture device having at least two electrodes attached to an outside surface of its housing. The device generates stimulation pulses in accordance with a specified stimulation regimen. Power management circuitry within the device allows a primary battery, having a high internal impedance, to be used to power the device. The stimulation regimen generates stimulation pulses during a stimulation session of duration T3 minutes applied every T4 minutes. The duty cycle, or ratio T3/T4 is very low, no greater than 0.05. The low duty cycle and careful power management allow the IEAD to perform its intended function for several years.

Claims

1. An Implantable ElectroAcupuncture System (IEAS) for treating cardiovascular disease through application of electroacupuncture (EA) stimulation pulses applied at a specified tissue location of a patient, comprising:

an implantable electroacupuncture (EA) device comprising

a small, hermetically-sealed housing containing a primary power source, pulse generation circuitry powered by the primary power source, and a sensor that wirelessly senses operating commands generated external to the housing, wherein the pulse generation circuitry generates stimulation pulses in accordance with a specified stimulation regimen as controlled at least in part by the operating commands sensed through the sensor;

a plurality of electrode arrays, where an electrode array comprises an array of n conductive contacts electrically joined together to function jointly as one electrode, where n is an integer, on the outside of the EA device housing electrically coupled to the pulse generation circuitry on the inside of the EA device housing through at least one feed-through terminal passing through a wall of the hermetically-sealed housing, whereby the stimulation pulses generated by the pulse generation circuitry are directed to the electrode arrays on the outside of the EA device housing, where the electrical pulses are applied at the specified tissue location through the plurality of electrode arrays in accordance with the specified stimulation regimen;

wherein the specified stimulation regimen defines how often a stimulation session comprising a stream of stimulation pulses is applied to the patient, the stimulation regimen requiring that the stimulation session have a duration of T3 minutes and a rate of occurrence of once every T4 minutes, wherein the ratio of T3/T4 is no greater than 0.05.

2. The IEAS of claim 1 wherein at least one of the plurality of electrode arrays is located at the distal end of a short pigtail lead attached to the EA device.

3. The IEAS of claim 1 wherein the plurality of electrode arrays are located on an outside surface of the case of the implantable EA device.

4. The IEAS of claim 3 wherein the plurality of electrode arrays are located on a bottom surface of the case of the implantable EA device.

5. The IEAS of claim 4 wherein a first one of the plurality of electrode arrays is centrally located on the bottom surface of the case of the implantable EA device and a second one of the plurality of electrode arrays surrounds the first array.

6. The IEAS of claim 1 wherein the dimensions of the EA device are L×

W×

H, where L is the longest linear dimension, W is the shortest linear dimension measured in substantially the same plane as L, and H is the maximum height or thickness of the housing measured in a plane orthogonal with the plane where L and W are measured, and wherein L is no greater than about 25 mm, W is no less than about 15 mm and H is no greater than about 3 mm.

7. The IEAS of claim 1 wherein the primary power source of the EA device comprises a battery having a nominal output voltage of no more than 3.0 volts and an internal impedance of no less than about 5 ohms.

8. The IEAS of claim 7 wherein the pulse generation circuitry includes:

a boost converter circuit that boosts the nominal voltage of the primary battery to an output voltage V_OUT that is at least three times the nominal battery voltage;

a control circuit that selectively turns the boost converter circuit OFF and ON to limit the amount of current that may be drawn from the primary battery; and

an output circuit powered by V_OUT and controlled by the control circuit that generates the stimulation pulses as defined by the specified stimulation regimen.

9. The IEAS of claim 8 wherein the stimulation pulses generated by the pulse generation circuit and delivered through the plurality of electrode arrays into a load at the specified tissue location comprise voltage pulses having a voltage amplitude of no less than about 1 V and no greater than about 15 V.

10. The IEAS of claim 8 wherein the stimulation pulses generated by the pulse generation circuit and delivered through the plurality of electrode arrays into a load at the specified tissue location comprise current pulses having a current amplitude of no less than about 1 milliampere (mA) and no greater than about 15 mA.

11. The IEAS of claim 10 wherein the primary battery has sufficient capacity to power the pulse generation circuitry in accordance with the specified stimulation regimen for a minimum of 2 years.

12. The IEAS of claim 1 wherein the duration of the stimulation session T3 varies between 10 minutes and 60 minutes if the rate of occurrence of the stimulation session T4 is set to a value between 1,200 minutes and 20,160 minutes [14 days];

and wherein T3 varies between 10 minutes and a maximum T3 value, T3(max) if T4 is set to a value between 720 minutes and 1,200 minutes, wherein the value of T3(max) varies as a function of T4 as defined by the equation;

T3(max)=0.05*T4.

13. The IEAS of claim 1 further including an external control device adapted to selectively generate operating commands that are sensed by the sensor within the implantable EA device.

14. The IEAS of claim 13 wherein the sensor within the implantable EA device comprises a magnetic field sensor, and where the external control device comprises a magnet.

15. An Implantable ElectroAcupuncture System (IEAS) for treating cardiovascular disease through application of electroacupuncture (EA) stimulation pulses adapted to be applied at at least one of acupoints EX-HN1, BL14, HT7, HT5, PC6, ST36, LI11, LU7, and LU2, comprising

an external magnetic field generating device;

and

an implantable electroacupuncture (IEAD) device, comprising

a small, self-contained, thin, hermetically-sealed, coin-sized and coin-shaped housing containing a primary power source having an internal impedance greater than 5 ohms, pulse generation circuitry powered by the primary power source, power management circuitry that controls how much power may be. drawn from the primary power source, and a magnetic sensor that senses the presence or absence of an external magnetic field, wherein the pulse generation circuitry generates stimulation pulses in accordance with a specified stimulation regimen as initiated by the magnetic sensor sensing a prescribed sequence of the presence and absence of an external magnetic field;

a plurality of implantable electrodes located outside of the IEAD housing coupled to the pulse generation circuitry on the inside of the IEAD housing through at least one feed-through terminal passing through a wall of the hermetically-sealed housing, whereby the stimulation pulses generated by the pulse generation circuitry are adapted to be applied through the implantable electrodes to at least one of the specified acupoints in accordance with the specified stimulation regimen;

wherein the specified stimulation regimen defines how often a stimulation session comprising a stream of stimulation pulses is applied to the at least one specified acupoint, the stimulation regimen requiring that the stimulation session have a duration of T3 minutes, where T3 is at least 10 minutes, and a rate of occurrence of once every T4 minutes, wherein the ratio of T3/T4 is no greater than 0.05; and

wherein the pulse generation circuitry and power management circuitry cause stimulation pulses to be continuously applied through the electrodes in accordance with the specified stimulation regimen once the stimulation regimen has been initiated.

16. The implantable IEAS, as defined in claim 15, wherein the primary power source housed within the IEAD housing comprises a thin coin-cell battery having a nominal output battery voltage, V_BAT, of 3 volts, and wherein the pulse generation circuitry is configured to generate stimulation pulses having a magnitude of up to 15 volts, and further wherein the power management circuitry manages the expenditure of power within the IEAD so that the IEAD performs its intended function of continuously generating stimulation pulses in a stimulation session of duration T3 minutes that occurs once every T4 minutes for over 2 years.

17. The implantable IEAS, as defined in claim 15, wherein the IEAD comprises a leadless device wherein the implantable electrodes are formed on an outside surface of the IEAD housing and configured in a symmetrical manner, with one electrode comprising a central electrode and another electrode comprising an annular electrode that surrounds the central electrode.

18. The implantable IEAS, as defined in claim 17, wherein the annular electrode is formed around a circumferential edge of the coin-shaped housing of the IEAD.

19. The implantable IEAS, as defined in claim 15, wherein the prescribed sequence of the presence and absence of an external magnetic field that must be sensed by the magnetic sensor within the IEAD housing in order initiate the specified stimulation regimen comprises:

(i) the absence of a magnetic field;

(ii) the presence of a magnetic field for 10 seconds;

(iii) the continued presence of the magnetic field for an additional plurality of 5 second intervals, during which the amplitude of the stimulus pulse increases every 5 seconds starting at zero amplitude and ending when a comfortable stimulus amplitude has been reached;

(iv) whereupon the external magnetic field is removed, and the stimulation session begins and continues for T3 minutes, after which a time interval, T_I, begins that defines the time interval between stimulus sessions, after which interval the next stimulation session begins and continues for T3 minutes, after which the time interval T_I begins again, and this sequence of stimulus sessions of duration T3 seconds followed by an interval of T_I continues over and over again regardless of whether an external magnetic field is present or not.

20. An Implantable ElectroAcupuncture System (IEAS) for treating cardiovascular disease through application of electroacupuncture (EA) stimulation pulses adapted to be applied at or near a specified acupoint, comprising:

a rigid, coin-shaped housing having a thickness of no greater than about 2.5 mm and a diameter no greater than about 25 mm;

at least one cathodic electrode and at least one anodic electrode formed in a prescribed configuration as an integral part of at least one outside surface of the housing;

stimulation circuitry residing inside the housing and electrically coupled to the at least one cathodic and at least one anodic electrodes, wherein the stimulation circuitry generates EA stimulation pulses that are delivered to body tissue through the at least one cathodic and at least one anodic electrodes in accordance with a prescribed stimulation regimen, wherein said stimulation regimen defines the duration and rate at which a stimulation session is applied to the patient, said stimulation regimen requiring that the stimulation session have a duration of T3 minutes, wherein T3 is at least 10 minutes, and a rate of occurrence of once every T4 minutes, wherein the ratio of T3/T4 is no greater than 0.05, and wherein during each stimulation session EA stimulation pulses having one or more specified widths and amplitudes are generated at one or more specified rates; and

a coin-cell type primary battery residing inside the housing that provides the operating power for the stimulation circuitry, wherein the primary battery has an internal impedance that is greater than 5 ohms;

wherein the IEAD is leadless and the IEAD housing is hermetically-sealed, and the coin-cell primary battery has sufficient capacity to power the operation of the IEAD in accordance with the prescribed stimulation regimen for at least two years without any further action needed on the part of the patient or other medical personnel; and

wherein the at least one cathodic electrode is located on a top or bottom surface of the housing and positioned no closer than 5 mm from the closest edge of the nearest at least one anodic electrode, wherein at least one of the cathodic or anodic electrodes comprises an annular or circumscribing electrode that surrounds or encompasses the other at least one cathodic or anodic electrodes, and wherein the total surface area of the at least one cathodic electrode is no smaller than about 0.5 mm², and wherein the positioning and surface area of the at least one cathodic electrode is selected to allow a desired current density to flow through the electrode surface area without causing electrode corrosion or current shunting.