Therapeutic electrical stimulation that avoids undesirable activation

• US 20080071318A1
• Filed: 09/14/2006
• Published: 03/20/2008
• Est. Priority Date: 09/14/2006
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Dong, Yanting, Sathaye, Alok S., Brooke, M. Jason, Walczak, Scott
• Granted Patent: US 8,209,013 B2
• Time in Patent Office: Days
• US Class Current: 607/28
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
• CPC Class Codes: A61N 1/3712 Auto-capture, i.e. automatic adjustment of the stimulation threshold

Abstract

Approaches for determining energy parameters for electrical stimulation pulses that produce a desired activation and avoid an undesirable activation are described. A strength-duration relationship for at least one desired activation produced by therapeutic electrical stimulation is measured. A strength-duration relationship for at least one undesirable activation produced by the therapeutic electrical stimulation is provided. A medical device selects, based on the desired and undesirable strength-duration relationships, one or more energy parameters for the therapeutic electrical stimulation that produce the desired activation and avoid the undesirable activation.

Claims

1. A method implementable by a medical device to select energy parameters for therapeutic electrical stimulation, comprising:

measuring a strength-duration relationship for at least one desired activation produced by the therapeutic electrical stimulation;

providing a strength-duration relationship for at least one undesirable activation produced by the therapeutic electrical stimulation; and

selecting, based on the desired and undesirable strength-duration relationships, one or more energy parameters for the therapeutic electrical stimulation that produce the desired activation and avoid the undesirable activation.

2. The method of claim 1, wherein the strength-duration relationship for the desired activation comprises a strength-duration relationship for capture of a heart by pacing pulses delivered to the heart.

3. The method of claim 1, wherein measuring the strength-duration relationship for the desired activation comprises automatically measuring the strength-duration relationship for capture.

4. The method of claim 1, wherein providing the strength-duration relationship for the undesirable activation comprising providing an energy parameter threshold for undesirable activation for a particular patient.

5. The method of claim 1, wherein providing the strength-duration relationship for undesirable activation comprises measuring the strength-duration relationship for undesirable activation for a particular patient.

6. The method of claim 1, wherein providing the strength-duration relationship for undesirable activation comprises determining the strength-duration relationship for undesirable activation based on theoretical analysis.

7. The method of claim 1, wherein providing the strength-duration curve for the undesirable activation comprises determining the strength duration relationship for the undesirable activation based on population data.

8. The method of claim 1, wherein:

determining the strength-duration relationship for the desired activation comprises determining a multiple-point strength-duration curve for the desired activation;

determining the strength-duration relationship for undesirable activation comprises determining a multiple-point strength-duration curve for undesirable activation; and

selecting the energy parameters for the therapeutic electrical stimulation comprises selecting the energy parameters from a region between the desired activation strength-duration curve and the undesirable activation strength-duration curve.

9. The method of claim 1, wherein:

the desired activation comprises cardiac capture; and

the undesirable activation comprises nerve or muscle activation.

10. The method of claim 1, wherein:

the desired activation comprises nerve activation; and

the undesirable activation comprises muscle activation.

11. The method of claim 1, wherein:

the desired activation comprises cardiac capture at a cathodal pacing site; and

the undesirable activation comprises cardiac capture at an anodal pacing site.

12. The method of claim 1, wherein:

determining the strength-duration relationship for the desired activation comprises performing a test to determine a capture amplitude threshold for cardiac pacing;

providing the strength-duration relationship for undesirable activation comprises providing a amplitude threshold for undesirable activation; and

selecting the energy parameters for the therapeutic electrical stimulation comprises;

comparing the capture amplitude threshold determined by the test to the undesirable activation threshold;

modifying one or more test energy parameters based on the comparison; and

selecting the energy parameters for the therapeutic electrical stimulation comprises selecting energy parameters that produce capture and avoid undesirable activation based on the modified test energy parameters.

13. The method of claim 12, wherein the one or more modified test energy parameters comprise one or more of a stimulation pulse amplitude and a stimulation pulse width.

14. The method of claim 12, wherein the one or more modified test energy parameters comprise one or more of a stimulation pulse frequency, a stimulation pulse duty cycle and a stimulation pulse geometry.

15. The method of claim 12, wherein modifying the one or more test energy parameters comprises modifying a stimulation pulse amplitude of the test to the amplitude threshold of undesirable activation or the amplitude threshold of undesirable activation adjusted by a predetermined margin.

16. The method of claim 1, further comprising providing an alert if the selected energy parameters for the therapeutic electrical stimulation exceed the strength-duration relationship for undesirable activation.

17. A therapy device, comprising:

electrodes configured to deliver therapeutic electrical stimulation;

measurement circuitry configured to measure a strength-duration relationship for at least one desired activation;

a therapy control processor configured to select, based on the strength-duration relationship for the desired activation and a strength-duration relationship for at least one undesirable activation, energy parameters for the therapeutic electrical stimulation that produces the desired activation and avoids the undesirable activation.

18. A device of claim 17, wherein:

the electrodes are electrically coupled to a heart;

the therapeutic electrical stimulation comprises pacing pulses to the heart;

the measurement circuitry comprises capture circuitry configured to measure a strength-duration relationship for capture of the heart; and

the therapy control processor is configured to select, based on the strength-duration relationship for capture and the strength-duration relationship for the undesirable activation, energy parameters for the pacing pulses that produce capture of the heart and avoid undesirable activation.

19. The device of claim 17, wherein:

the strength-duration relationship for the desired activation comprises a multiple-point strength-duration curve;

the strength-duration relationship for undesirable activation threshold comprises a multiple-point strength-duration curve for undesirable activation; and

the therapy control processor is configured to select the energy parameters for the therapeutic electrical stimulation based on a region defined by the strength-duration curve for the desired activation and the strength-duration curve for the undesirable activation.

20. The device of claim 17, wherein the desired activation comprises cardiac capture and the undesirable activation comprises nerve or muscle activation.

21. The device of claim 17, wherein the desired activation comprises nerve activation and the undesirable activation comprises muscle activation.

22. The device of claim 17, wherein:

the desired activation comprises capture at a cathodal pacing site; and

the undesirable activation comprises capture at an anodal pacing site.

23. The device of claim 17, wherein:

the strength-duration relationship of the desired activation comprises a cardiac capture amplitude threshold;

the measurement circuitry is configured to measure the capture amplitude threshold during a capture threshold test; and

the therapy processor is configured to compare the capture amplitude threshold determined by the test to an undesirable activation amplitude threshold and to modify at least one test energy parameter based on the comparison.

24. The device of claim 23, wherein the at least one modified energy parameter comprises a pulse width.

25. The device of claim 23, wherein the at least one modified energy parameter comprises a pulse amplitude.

26. The device of claim 23, wherein the therapy control processor is configured to provide an alert if the selected energy parameters exceed the strength-duration relationship for undesirable activation.

27. A system for determining energy parameters for pacing pulses delivered to a patient'"'"'s heart, comprising:

means for determining a strength-duration relationship for capture of the heart;

means for providing a strength-duration relationship for undesirable activation; and

means for selecting, based on the strength-duration for capture and the strength-duration relationship for undesirable activation, energy parameters that provide for capture of the heart and avoid the undesirable activation.

28. The system of claim 27, further comprising:

means for performing a capture threshold test to determine a capture amplitude threshold;

means for comparing the capture amplitude threshold to the strength-duration relationship of undesirable activation; and

means for modifying at least one test energy parameter based on the comparison.