THERAPY SYSTEM INCLUDING CARDIAC RHYTHM THERAPY AND NEUROSTIMULATION CAPABILITIES

• US 20100114221A1
• Filed: 10/30/2009
• Published: 05/06/2010
• Est. Priority Date: 10/31/2008
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Krause, Paul G., Scheiner, Avram
• Granted Patent: US 8,527,045 B2
• Time in Patent Office: Days
• US Class Current: 607/7
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362
• CPC Class Codes: A61N 1/36514 controlled by a physiological quantity other than heart potential, e.g. blood pressure controlled by two or more physical parameters A61N1/36585
• CPC Class Codes: A61N 1/36521 the parameter being derived from measurement of an electrical impedance

Abstract

An implantable medical system that includes a cardiac therapy module and a neurostimulation therapy module may identify when neurostimulation electrodes have migrated toward a patient'"'"'s heart. In some examples, the system may determine whether the neurostimulation electrodes have migrated toward the patient'"'"'s heart based on a physiological response to an electrical signal delivered to the patient via the neurostimulation electrodes. In addition, in some examples, the system may determine whether the neurostimulation electrodes have migrated toward the patient'"'"'s heart based on an electrical cardiac signal sensed via the neurostimulation electrodes.

Claims

1. A method comprising:

delivering cardiac rhythm therapy to a heart of a patient via a first set of electrodes of a first lead electrically connected to a cardiac therapy module;

delivering an electrical stimulation signal to a tissue site within a patient via a second set of electrodes of a second lead electrically connected to a neurostimulation therapy module;

sensing an electrical cardiac signal with the second set of electrodes of the second lead;

determining whether the electrical cardiac signal indicates the second set of electrodes of the second lead is at least a predetermined distance away from the heart of the patient; and

controlling the neurostimulation therapy module to deliver neurostimulation therapy to the patient if the electrical cardiac signal indicates the second set of electrodes of the second lead is at least the predetermined distance away from the heart.

2. The method of claim 1, further comprising controlling the neurostimulation therapy module to adjust the delivery of neurostimulation therapy to the patient if the second set of electrodes of the second lead is not at least the predetermined distance away from the heart.

3. The method of claim 2, wherein controlling the neurostimulation therapy module to adjust the delivery of neurostimulation therapy comprises controlling the neurostimulation therapy module to withhold the delivery of neurostimulation therapy.

4. The method of claim 2, wherein controlling the neurostimulation therapy module to adjust the delivery of neurostimulation therapy comprises controlling the neurostimulation therapy module to deliver therapy to the patient according to a modified neurostimulation therapy parameter.

5. The method of claim 1, wherein determining whether the second set of electrodes of the second lead is at least the predetermined distance away from the heart of the patient based on the electrical cardiac signal comprises comparing an amplitude of the electrical cardiac signal to a threshold value, and determining that the second set of electrodes of the second lead is at least the predetermined distance away from the heart of the patient if the amplitude of the electrical cardiac signal is less than or equal to the threshold value.

6. The method of claim 1, wherein determining whether the second set of electrodes of the second lead is at least the predetermined distance away from the heart of the patient based on the electrical cardiac signal comprises detecting a physiological response to the delivery of the electrical stimulation signal via the second set of electrodes of the second lead based on the cardiac signal.

7. The method of claim 6, wherein the physiological response comprises cardiac capture.

8. The method of claim 1, wherein the electrical cardiac signal comprises a first electrical cardiac signal, the method further comprising sensing a second electrical cardiac signal with the first set of electrodes of the first lead, wherein determining whether the second set of electrodes of the second lead is at least the predetermined distance away from the heart of the patient comprises comparing the first and second electrical cardiac signals.

9. The method of claim 8, wherein comparing the first and second electrical cardiac signals comprises:

comparing a difference between a first amplitude of the first electrical cardiac signal and a second amplitude of the second electrical cardiac signal to a threshold value; and

determining that the second set of electrodes of the second lead is at least the predetermined distance away from the heart if a difference between the first and second amplitudes is greater than or equal to a threshold value.

10. The method of claim 8, wherein comparing the first and second electrical cardiac signals comprises correlating the first and second electrical cardiac signals to determine a correlation value that indicates an extent of correlation between the first and second electrical cardiac signals, and determining that the second set of electrodes of the second lead is at least the predetermined distance away from the heart if the correlation value is less than or equal to a threshold value.

11. The method of claim 1, wherein the second set of electrodes of the second lead is implanted within vasculature of the patient.

12. The method of claim 1, wherein the cardiac rhythm therapy comprises at least one of pacing, cardioversion or defibrillation therapy.

13. The method of claim 1, wherein the cardiac therapy module and neurostimulation therapy module are enclosed in separate outer housings that are separately implantable within the patient.

14. The method of claim 1, wherein the cardiac therapy module and neurostimulation therapy module are enclosed in a common outer housing of an implantable medical device.

15. A system comprising:

a first lead comprising a first set of electrodes;

a second lead comprising a second set of electrodes;

a cardiac therapy module electrically connected to the first set of electrodes of the first lead, wherein the cardiac therapy module generates and delivers cardiac rhythm therapy to a heart of the patient via the first set of electrodes;

a neurostimulation therapy module electrically connected to the second set of electrodes of the second lead, wherein neurostimulation therapy module generates and delivers an electrical stimulation signal to a tissue site within the patient via the second set of electrodes;

a sensing module that senses an electrical cardiac signal of the patient;

a processor that determines whether the second set of electrodes of the second lead is at least a predetermined distance away from the heart of the patient based on the electrical cardiac signal and controls the neurostimulation therapy module to deliver neurostimulation therapy to the patient if the second set of electrodes of the second lead is at least the predetermined distance away from the heart.

16. The system of claim 15, wherein the processor controls the neurostimulation therapy module to adjust neurostimulation therapy to the patient if the second set of electrodes of the second lead is not at least the predetermined distance away from the heart.

17. The system of claim 16, wherein the processor controls the neurostimulation therapy module to adjust neurostimulation therapy to the patient by at least controlling the neurostimulation therapy module to withhold the delivery of neurostimulation therapy.

18. The system of claim 16, wherein the processor controls the neurostimulation therapy module to adjust neurostimulation therapy to the patient by at least controlling the neurostimulation therapy module to deliver therapy to the patient according to a modified neurostimulation therapy parameter.

19. The system of claim 15, wherein the processor determines whether the second set of electrodes of the second lead is at least the predetermined distance away from the heart of the patient by at least comparing an amplitude of the electrical cardiac signal to a threshold value, and determining that the second set of electrodes of the second lead is at least the predetermined distance away from the heart of the patient if the amplitude of the electrical cardiac signal is less than or equal to the threshold value.

20. The system of claim 15, wherein the processor determines whether the second set of electrodes of the second lead is at least the predetermined distance away from the heart of the patient by at least detecting a physiological response to the delivery of the electrical stimulation signal via the second set of electrodes of the second lead based on the cardiac signal.

21. The system of claim 15, wherein the electrical cardiac signal comprises a first electrical cardiac signal and the sensing module comprises a first sensing module, the system further comprising a second sensing module that senses a second electrical cardiac signal with the first set of electrodes of the first lead, wherein the processor determines whether the second set of electrodes of the second lead is at least the predetermined distance away from the heart of the patient by at least comparing the first and second electrical cardiac signals.

22. The system of claim 21, wherein the processor compares the first and second electrical cardiac signals by at least comparing a difference between a first amplitude of the first electrical cardiac signal and a second amplitude of the second electrical cardiac signal to a threshold value, and determines that the second set of electrodes of the second lead is at least the predetermined distance away from the heart if a difference between the first and second amplitudes is greater than or equal to a threshold value.

23. The system of claim 21, wherein the processor compares the first and second electrical cardiac signals by at least correlating the first and second electrical cardiac signals to determine a correlation value that indicates an extent of correlation between the first and second electrical cardiac signals, and determines that the second set of electrodes of the second lead is at least the predetermined distance away from the heart if the correlation value is less than or equal to a threshold value.

24. The system of claim 15, wherein the cardiac therapy module and the neurostimulation therapy module are enclosed within a common outer housing of an implantable medical device.

25. The system of claim 15, further comprising a first implantable medical device (IMD) comprising a first outer housing enclosing the cardiac therapy module and a second IMD comprising a second outer housing enclosing the neurostimulation therapy module, wherein the first and second outer housings are physically separate from each other and separately implantable within the patient.

26. A system comprising:

means for delivering cardiac rhythm therapy to a heart of a patient via a first set of electrodes of a first lead;

means for delivering an electrical stimulation signal to a tissue site within a patient via a second set of electrodes of a second lead;

means for sensing an electrical cardiac signal with second set of electrodes of the second lead;

means for determining whether the second set of electrodes of the second lead is at least a predetermined distance away from the heart of the patient based on the electrical cardiac signal; and

means for controlling the means for delivering the electrical stimulation signal to deliver neurostimulation therapy to the patient if the second set of electrodes of the second lead is at least the predetermined distance away from the heart.

27. The system of claim 26, wherein the means for determining whether the second set of electrodes of the second lead is at least the predetermined distance away from the heart of the patient based on the electrical cardiac signal comprises means for comparing an amplitude of the electrical cardiac signal to a threshold value, wherein the means for determining whether the second set of electrodes of the second lead is at least the predetermined distance away from the heart determines that the second set of electrodes of the second lead is at least the predetermined distance away from the heart of the patient if the amplitude of the electrical cardiac signal is less than or equal to the threshold value.

28. The system of claim 26, wherein the means for determining whether the second set of electrodes of the second lead is at least the predetermined distance away from the heart of the patient based on the electrical cardiac signal comprises means for detecting a physiological response to the delivery of the electrical stimulation signal via the second set of electrodes of the second lead based on the cardiac signal.

29. The system of claim 26, wherein the an electrical cardiac signal comprises a first electrical cardiac signal, the system further comprising means for sensing a second electrical cardiac signal with the first set of electrodes of the first lead, wherein the means for determining whether the second set of electrodes of the second lead is at least the predetermined distance away from the heart of the patient comprises means for comparing the first and second electrical cardiac signals.

30. A computer-readable medium comprising instructions that cause a programmable processor to:

control a cardiac therapy module to deliver cardiac rhythm therapy to a heart of a patient via a first set of electrodes of a first lead electrically connected to the cardiac therapy module;

control a neurostimulation therapy module to deliver an electrical stimulation signal to a tissue site within a patient via a second set of electrodes of a second lead electrically connected to the neurostimulation therapy module;

control a sensing module to sense an electrical cardiac signal with the second set of electrodes of the second lead;

determine whether the electrical cardiac signal indicates the second set of electrodes of the second lead is at least a predetermined distance away from the heart of the patient; and

control the neurostimulation therapy module to deliver neurostimulation therapy to the patient if the electrical cardiac signal indicates the second set of electrodes of the second lead is at least the predetermined distance away from the heart.