Methods and apparatus for improved IPG rate response using subcutaneous electrodes directly coupled to an implantable medical device (IMD)

• US 9,381,366 B2
• Filed: 03/16/2007
• Issued: 07/05/2016
• Est. Priority Date: 03/16/2007
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Stancer, Christopher C.
• Primary Examiner(s): Levicky, William
• Application Number:
  US11/687,465
• Publication Number:
  US 20080228234A1
• Time in Patent Office: 3,399 Days
• Field of Search: 607 9- 28
• US Class Current: 1/1
• CPC Class Codes: A61B 5/287 Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61N 1/0504 Subcutaneous electrodes
• CPC Class Codes: A61N 1/36585 controlled by two or more physical parameters
• CPC Class Codes: A61N 1/375 Constructional arrangements, e.g. casings
• CPC Class Codes: A61N 1/37512 Pacemakers
• CPC Class Codes: A61N 1/37518 Anchoring of the implants, e.g. fixation
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators

Abstract

Per the disclosure subcutaneously implantable medical devices (IMDs) with rate responsive implantable pulse generator (IPG) capability that also include dual patient activity sensors are adaptively controlled. One of the activity sensors uses multiple electrodes adapted to acquire electrocardiographic signals and signals from non-cardiac muscle tissue (myopotentially-based signals). The signals from the electrode-based activity sensor are used to confirm and/or override the patient-activity sensor signals from the other non-myopotentially-based patient activity sensor. The electrodes are directly mechanically coupled to the housing of the IMD and electrically coupled to circuitry that filters, processes, and interprets both the patient activity sensor signals.

Claims

1. A method of controlling a rate responsive cardiac pacing scheme, comprising:

receiving a non-myopotentially-based patient activity sensor signal from a sensor coupled to an implantable medical device (IMD);

receiving a myopotential-based patient activity sensor signal from at least a pair of surface electrodes mechanically coupled to a portion of the IMD; and

logically combining the non-myopotentially-based patient activity sensor signal and the myopotentially-based patient activity signal to control a rate responsive cardiac pacing scheme of the IMD; and

delivering cardiac pacing to the patient according to the rate responsive pacing scheme;

further comprising filtering the non-myopotentially-based patient activity sensor signal and the myopotentially-based patient activity signal prior to logically combining the non-myopotentially-based patient activity sensor signal and the myopotentially-based patient activity signal.

2. A subcutaneously implantable device, comprising:

a subcutaneously implantable device housing;

a patient activity sensor disposed within the device housing providing a patient activity output signal;

a pair of spaced apart subcutaneous electrodes mounted to the device housing;

circuit means for receiving, processing, and filtering the patient activity output signal and for receiving, processing, and filtering myopotential signals from the electrodes and for providing both a non-myopotential-based patient activity signal and an a myopotential-based patient activity signal therefrom and for logically combining the myopotential-based patient activity signal and the non-myopotential-based patient activity to control a rate responsive cardiac pulse stimulator.

3. A device according to claim 2, wherein the patient activity sensor disposed within the device housing comprises a piezoelectrically-based motion sensor.

4. A device according to claim 2, wherein said patient activity sensor disposed within the device housing comprises one of a single axis accelerometer and a multi-axis accelerometer.

5. A device according to claim 2, wherein the IMD comprises one of an implantable cardiac pacemaker and an implantable cardioverter-defibrillator.

6. A subcutaneously implantable device, comprising:

a subcutaneously implantable device housing;

a patient activity sensor disposed within the device housing providing a patient activity output signal;

a pair of spaced apart subcutaneous electrodes mounted to the device housing;

circuit means for receiving, processing, and filtering the patient activity output signal and for receiving, processing, and filtering myopotential signals from the electrodes and for providing both a non-myopotential-based patient activity signal and an a myopotential-based patient activity signal therefrom and for logically combining the myopotential-based patient activity signal and the non-myopotential-based patient activity to control a rate responsive cardiac pulse stimulator; and

further comprising filters which filter the non-myopotentially-based signal and the myopotentially-based signal prior to logically combining the non-myopotentially-based signal and the myopotentially-based signal.

7. A subcutaneously implantable device, comprising:

a subcutaneously implantable device housing;

a patient activity sensor disposed within the device housing providing a patient activity output signal;

a pair of spaced apart subcutaneous electrodes mounted to the device housing;

circuit means for receiving, processing, and filtering the patient activity output signal and for receiving, processing, and filtering myopotential signals from the electrodes and for providing both a non-myopotential-based patient activity signal and an a myopotential-based patient activity signal therefrom and for logically combining the myopotential-based patient activity signal and the non-myopotential-based patient activity to control a rate responsive cardiac pulse stimulator; and

wherein the circuit means for logically combining the non-myopotential-based and the myopotentially-based patient activity signals employs the myopotentially-based patient activity signals to confirm a low level of detected patient activity indicated by the non-myopotentially-based patient activity signal.

8. A subcutaneously implantable device, comprising:

a subcutaneously implantable device housing;

a patient activity sensor disposed within the device housing providing a patient activity output signal;

a pair of spaced apart subcutaneous electrodes mounted to the device housing;

circuit means for receiving, processing, and filtering the patient activity output signal and for receiving, processing, and filtering myopotential signals from the electrodes and for providing both a non-myopotential-based patient activity signal and an a myopotential-based patient activity signal therefrom and for logically combining the myopotential-based patient activity signal and the non-myopotential-based patient activity to control a rate responsive cardiac pulse stimulator; and

wherein the circuit means for logically combining the non-myopotential-based and the myopotentially-based patient activity signals employs the myopotentially-based patient activity signals responsive to a cardiac pulse rate falling below a defined level.

9. A method of controlling a rate responsive cardiac pacing scheme, comprising:

receiving a non-myopotentially-based patient activity signal from a sensor coupled to an implantable medical device (IMD) implanted within a patient;

deriving a myopotential-based patient activity signal from at least a pair of surface electrodes mechanically coupled to a portion of the IMD; and

logically combining the non-myopotentially-based patient activity signal and the myopotentially-based patient activity signal to control a rate responsive cardiac pacing scheme of the IMD; and

delivering cardiac pacing to the patient according to the rate responsive pacing scheme;

wherein logically combining the non-myopotential-based and the myopotentially-based patient activity signals comprises employing the myopotentially-based patient activity signals to confirm a low level of detected patient activity indicated by the non-myopotentially-based patient activity signal.

10. A method of controlling a rate responsive cardiac pacing scheme, comprising:

receiving a non-myopotentially-based patient activity signal from a sensor coupled to an implantable medical device (IMD) implanted within a patient;

deriving a myopotential-based patient activity signal from at least a pair of surface electrodes mechanically coupled to a portion of the IMD; and

logically combining the non-myopotentially-based patient activity signal and the myopotentially-based patient activity signal to control a rate responsive cardiac pacing scheme of the IMD; and

delivering cardiac pacing to the patient according to the rate responsive pacing scheme;

wherein logically combining the non-myopotential-based and the myopotentially-based patient activity signals comprises employing the myopotentially-based patient activity signals employs the myopotentially-based patient activity signals responsive to a cardiac pacing rate falling below a defined level.