Posture estimation at transitions between states

• US 20070129641A1
• Filed: 12/01/2005
• Published: 06/07/2007
• Est. Priority Date: 12/01/2005
• Status: Abandoned Application

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Sweeney, Robert
• Application Number:
  US11/291,479
• Publication Number:
  US 20070129641A1
• Time in Patent Office: Days
• US Class Current: 600/513
• CPC Class Codes: A61N 1/36535 controlled by body position or posture
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration

Abstract

An implanted device includes a posture sensor configured to produce one or more electrical signals associated with an orientation of the posture sensor relative to a direction of gravity. The device also includes a processor coupled to the posture sensor, the processor being programmed to process the electrical signals from the posture sensor using hysteresis, and to estimate one of a plurality of posture states based on the processed electrical signals.

Claims

1. An implanted device, comprising:

a posture sensor configured to produce one or more electrical signals associated with an orientation of the posture sensor relative to a direction of gravity; and

a processor coupled to the posture sensor, the processor being programmed to process the electrical signals from the posture sensor using hysteresis, and to estimate one of a plurality of posture states based on the processed electrical signals.

2. The device of claim 1, wherein the processor is programmed to define a transition band about a transition line between two posture states to implement hysteresis.

3. The device of claim 2, wherein the transition band includes first and second thresholds, wherein the first and second thresholds are pre-determined.

4. The device of claim 2, wherein the transition band includes first and second thresholds, wherein the first and second thresholds are varied over time.

5. The device of claim 1, wherein the device is a cardiac rhythm management device.

6. The device of claim 1, wherein the posture sensor is configured to sense the orientation in one dimension.

7. The device of claim 1, wherein the posture sensor is configured to sense the orientation in two or more dimensions.

8. An implanted cardiac rhythm management device, comprising:

a posture sensor configured to produce one or more electrical signals associated with an orientation of the posture sensor relative to a direction of gravity;

a processor coupled to the posture sensor, the processor being programmed to process the electrical signals from the posture sensor using hysteresis, and to estimate one of a plurality of posture states based on the processed electrical signals; and

a transceiver module programmed to transmit the estimate of the one posture state to an external device.

9. The device of claim 8, wherein the processor is programmed to define a transition band about a transition line between two posture states to implement hysteresis.

10. The device of claim 9, wherein the transition band includes first and second thresholds, wherein the first and second thresholds are predetermined.

11. The device of claim 9, wherein the transition band includes first and second thresholds, wherein the first and second thresholds are varied over time.

12. The device of claim 8, wherein the posture sensor is configured to sense the orientation in one dimension.

13. The device of claim 8, wherein the posture sensor is configured to sense the orientation in two or more dimensions.

14. The device of claim 8, further comprising a therapy module coupled to the processor, the therapy module being configured to deliver therapy.

15. A method for estimating posture using an implanted device, the method comprising:

generating one or more signals indicative of an orientation of the device relative to a direction of gravity;

processing the signals by defining a transition band about a transition line between posture states of a plurality of posture states; and

estimating one of the plurality of posture states based on the processed signals.

16. The method of claim 15, further comprising transmitting the estimate of the one posture state to an external device.

17. The method of claim 15, wherein processing the signals further comprises using hysteresis to process the signals.

18. The method of claim 15, wherein defining further comprises defining the transition band to include first and second thresholds, wherein the first and second thresholds are pre-determined.

19. The method of claim 15, wherein defining further comprises defining the transition band to include first and second thresholds, wherein the first and second thresholds are varied over time.

20. The method of claim 15, wherein estimating further comprises:

estimating a change in posture from a first posture state to a second posture state of the plurality of posture states when the signals go above a first threshold of the transition band; and

estimating a change in posture from the second posture state to the first posture state of the plurality of posture states when the signals go below a second threshold of the transition band.