IMPLANTABLE MEDICAL DEVICE CROSSTALK EVALUATION AND MITIGATION

• US 20100114202A1
• Filed: 01/30/2009
• 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., Donofrio, William T., Zhou, Xiaohong, Reinke, James D., Arne, Gerald P., Peichel, David J., Burnes, John E.
• Granted Patent: US 8,611,996 B2
• Time in Patent Office: Days
• US Class Current: 607/4
• CPC Class Codes: A61B 5/304 Switching circuits
• CPC Class Codes: A61B 5/308 for electrocardiography [ECG]
• CPC Class Codes: A61B 5/7217 of noise originating from a therapeutic or surgical apparatus, e.g. from a pacemaker
• CPC Class Codes: A61N 1/025 Digital circuitry features of electrotherapy devices, e.g. memory, clocks, processors
• CPC Class Codes: A61N 1/0551 Spinal or peripheral nerve electrodes
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362
• CPC Class Codes: A61N 1/36185 Selection of the electrode configuration
• CPC Class Codes: A61N 1/3686 configured for selecting the electrode configuration on a lead A61N1/3688 takes precedence
• CPC Class Codes: A61N 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371
• CPC Class Codes: A61N 1/3706 Pacemaker parameters stimulation threshold A61N1/371
• CPC Class Codes: A61N 1/3718 Monitoring of or protection against external electromagnetic fields or currents
• CPC Class Codes: A61N 1/37247 User interfaces, e.g. input or presentation means
• CPC Class Codes: A61N 1/37288 Communication to several implantable medical devices within one patient
• CPC Class Codes: A61N 1/39622 Pacing therapy
• CPC Class Codes: A61N 1/39624 Pain reduction therapy

Abstract

Electrical crosstalk between two implantable medical devices or two different therapy modules of a common implantable medical device may be evaluated, and, in some examples, mitigated. In some examples, one of the implantable medical devices or therapy modules delivers electrical stimulation to a nonmyocardial tissue site or a nonvascular cardiac tissue site, and the other implantable medical device or therapy module delivers cardiac rhythm management therapy to a heart of the patient.

Claims

1. A method comprising:

determining whether a therapy module is delivering electrical stimulation to a tissue site within a patient;

monitoring cardiac function of a heart of the patient according to a first sense mode if the therapy module is delivering electrical stimulation to the tissue site; and

monitoring cardiac function of the heart of the patient according to a second sense mode if the therapy module is not delivering electrical stimulation to the tissue site, wherein the first and second sense modes monitor at least one different non-electrophysiological parameter of the patient.

2. The method of claim 1, wherein the tissue site comprises at least one of a nonmyocardial tissue site or a nonvascular cardiac tissue site.

3. The method of claim 1, wherein the tissue site comprises at least one of an extravascular tissue site or the tissue site proximate to a nerve of the patient.

4. The method of claim 1, wherein monitoring cardiac function of the heart of the patient according to the second sense mode comprises monitoring cardiac function of the heart of the patient based on fewer non-electrophysiological parameters of the patient compared to the first sense mode.

5. The method of claim 1, wherein the monitoring cardiac function of the heart of the patient according to the first sense mode comprises monitoring at least one non-electrophysiological parameter of the patient, the non-electrophysiological parameter comprising at least one of cardiovascular pressure, tissue perfusion, blood oxygen saturation levels, heart sound signals, respiratory rate, intrathoracic impedance, cardiac mechanical activity, muscle movement, ultrasonic signals, heart rate, body temperature, or acoustic signals indicative of cardiac mechanical activity.

6. The method of claim 1, further comprising sensing at least one non-electrophysiological parameter of the patient indicative of cardiac function with at least one of an external or an implanted sensor.

7. The method of claim 1, wherein the first and second sense modes define different sense vectors for sensing the electrical cardiac signals.

8. The method of claim 7, wherein sensing electrical cardiac signals according to the first sense mode comprises sensing electrical cardiac signals within a left ventricle of a heart of the patient and outside of a right ventricle of the heart, and wherein sensing electrical cardiac signals according to the second sense mode comprises sensing electrical cardiac signals within the right ventricle of the heart of the patient and outside of the left ventricle of the heart.

9. The method of claim 7, wherein sensing electrical cardiac signals according to the first sense mode comprises sensing electrical cardiac signals via at least two electrodes of a lead electrically connected to a sensing module, and wherein sensing electrical cardiac signals according to the second sense mode comprises sensing electrical cardiac signals via at least one electrode of the lead and an electrode of a housing of a medical device comprising the sensing module.

10. The method of claim 7, wherein sensing electrical cardiac signals according to the first sense mode comprises sensing electrical cardiac signals via each of a plurality of sensing vectors.

11. The method of claim 10, further comprising:

determining a weighted sum of the electrical cardiac signals based on the applied weights; and

determining cardiac function of the patient based on the weighted sum of the electrical cardiac signals sensed via each of the plurality of sensing vectors.

12. The method of claim 10, further comprising:

determining a difference between the electrical cardiac signals sensed via each of the plurality of sensing vectors; and

determining cardiac function of the patient based on the difference between the electrical cardiac signals sensed via each of the plurality of sensing vectors.

13. The method of claim 1, wherein sensing electrical cardiac signals according to the first sense mode comprises sensing electrical cardiac signals via external electrodes, and sensing electrical cardiac signals according to the second sense mode comprises sensing electrical cardiac signals via implanted electrodes.

14. The method of claim 1, wherein therapy module comprises a first therapy module, and sensing electrical cardiac signals according to the first and second modes comprises sensing electrical cardiac signals via a sensing module, and wherein the first sense mode defines a first sense vector comprising a first subset of electrodes electrically connected to the sensing module and the second sense mode defines a second sense vector comprising a second subset of electrodes electrically connected to the sensing module, the first and second subsets of electrodes comprising at least one different electrode.

15. The method of claim 1, further comprising:

detecting a potential arrhythmia of the patient based on the electrical cardiac signals sensed according to the first sense mode; and

sensing the electrical cardiac signals according to the second sense mode upon detecting the potential arrhythmia.

16. The method of claim 15, wherein the therapy module comprises a first therapy module, the method further comprising:

detecting the potential arrhythmia based on the electrical cardiac signals sensed according to the second sense mode; and

delivering at least one of a pacing, cardioversion or defibrillation electrical signal to a heart of the patient with a second therapy module if the potential arrhythmia is detected based on the electrical cardiac signals sensed according to the second sense mode.

17. The method of claim 16, wherein the first and second therapy modules are enclosed in a common housing.

18. The method of claim 16, wherein the first therapy module is enclosed in a first housing of a first implantable medical device and the second therapy module is enclosed in a second housing of a second implantable medical device that is physically separate from the first implantable medical device.

19. The method of claim 15, further comprising:

determining whether the potential arrhythmia is detected based on the electrical cardiac signals sensed according to the second sense mode; and

sensing electrical cardiac signals according to the first sense mode if the potential arrhythmia is not detected based on the electrical cardiac signals sensed according to the second sense mode.

20. The method of claim 1, wherein the first and second sense modes define at least one of different sensing threshold levels or different amplifier gains for sensing the electrical cardiac signals.

21. The method of claim 1, wherein the first and second sense modes comprise different filters that are applied to the sensed electrical cardiac signals.

22. The method of claim 1, wherein the first and second sense modes comprise different potential arrhythmia event detection algorithms.

23. The method of claim 22, wherein the first sense mode defines an arrhythmia event detection algorithm that detects a potential arrhythmia based on a duration of an S-T segment of a sensed electrical cardiac signal.

24. The method of claim 1, wherein determining whether the therapy module is delivering electrical stimulation comprises at least one of receiving an indication from the therapy module or determining the therapy module is delivering stimulation based on known schedule.

25. A system comprising:

a therapy module that delivers electrical stimulation to a tissue site within a patient;

a sensing module that monitors cardiac function of a heart of the patient; and

a processor that determines whether the therapy module is delivering electrical stimulation to the tissue site, controls the sensing module to sense electrical cardiac signals according to a first sense mode if the therapy module is delivering electrical stimulation to the tissue site, and controls the sensing module to sense electrical cardiac signals according to a second sense mode site if the therapy module is not delivering electrical stimulation to the tissue site, wherein the first and second sense modes monitor at least one different non-electrophysiological parameter of the patient.

26. The system of claim 25, wherein the tissue site comprises at least one of a nonmyocardial tissue site or a nonvascular cardiac tissue site.

27. The system of claim 25, wherein the tissue site comprises at least one of an extravascular tissue site or the tissue site proximate to a nerve of the patient.

28. The system of claim 25, wherein when the sensing module monitors cardiac function of the heart of the patient according to the second sense mode, the sensing module monitors fewer non-electrophysiological parameters of the patient compared to the first sense mode.

29. The system of claim 25, wherein the sensing module monitors cardiac function of the heart of the patient according to the first sense mode by at least monitoring a non-electrophysiological parameter of the patient, the non-electrophysiological parameter comprising at least one of cardiovascular pressure, tissue perfusion, blood oxygen saturation levels, heart sound signals, respiratory rate, intrathoracic impedance, cardiac mechanical activity, muscle movement, ultrasonic signals, heart rate, body temperature, or acoustic signals indicative of cardiac mechanical activity.

30. The system of claim 25, wherein the sensing module comprises an external portion that monitors at least one non-electrophysiological parameter of the patient.

31. The system of claim 25, wherein the first and second sense modes define different sense vectors for sensing the electrical cardiac signals.

32. The system of claim 30, wherein in the first sense mode, the sensing module senses electrical cardiac signals within a left ventricle of a heart of the patient and outside of a right ventricle of the heart, and in the second sense mode, the sensing module senses electrical cardiac signals within the right ventricle of the heart of the patient and outside of the left ventricle of the heart.

33. The system of claim 30, wherein in the first sense mode, the sensing module senses electrical cardiac signals via at least two electrodes of a lead electrically connected to a sensing module, and in the second sense mode, the sensing module senses electrical cardiac signals via at least one electrode of the lead and an electrode of a housing of a medical device comprising the sensing module.

34. The system of claim 30, wherein in the first sense mode, the sensing module senses electrical cardiac signals via each of a plurality of sensing vectors.

35. The system of claim 30, wherein in the first sense mode, the sensing module senses electrical cardiac signals via external electrodes, and in the second sense mode, the sensing module senses electrical cardiac signals via implanted electrodes.

36. The system of claim 30, further comprising a plurality of electrodes coupled to the sensing module, wherein the first sense mode defines a first sense vector comprising a first subset of electrodes of the plurality of electrodes and the second sense mode defines a second sense vector comprising a second subset of electrodes of the plurality of electrodes, the first and second subsets of electrodes comprising at least one different electrode.

37. The system of claim 25, wherein the processor detects a potential arrhythmia of the patient based on the electrical cardiac signals sensed by the sensing module according to the first sense mode, and controls the sensing module to sense the electrical cardiac signals according to the second sense mode upon detecting the potential arrhythmia.

38. The system of claim 36, wherein the therapy module comprises a first therapy module, the system further comprising a second therapy module that delivers at least one of a pacing, cardioversion or defibrillation electrical signal to a heart of the patient, wherein the processor detects the potential arrhythmia based on the electrical cardiac signals sensed by the sensing module according to the second sense mode and controls the second therapy module to deliver the at least one of a pacing, cardioversion or defibrillation electrical signal to the heart of the patient if the potential arrhythmia is detected based on the electrical cardiac signals sensed according to the second sense mode.

39. The system of claim 36, wherein the processor determines whether the potential arrhythmia is detected based on the electrical cardiac signals sensed by the sensing module according to the second sense mode, and controls the sensing module to sense electrical cardiac signals according to the first sense mode if the arrhythmia is not detected based on the electrical cardiac signals sensed according to the second sense mode.

40. The system of claim 25, wherein the first and second sense modes define at least one of different sensing threshold levels or different amplifier gains for sensing the electrical cardiac signals.

41. The system of claim 25, wherein the first and second sense modes comprise different filters that are applied to the sensed electrical cardiac signals.

42. The system of claim 25, wherein the first and second sense modes comprise different potential arrhythmia event detection algorithms.

43. A system comprising:

means for determining whether a therapy module is delivering electrical stimulation to a tissue site within a patient;

means for monitoring cardiac function of a heart of the patient according to a first sense mode if the therapy module is delivering electrical stimulation to the tissue site; and

means for monitoring cardiac function of the heart of the patient according to a second sense mode if the therapy module is not delivering electrical stimulation to the tissue site, wherein the first and second sense modes monitor at least one different non-electrophysiological parameter of the patient.

44. The system of claim 43, wherein when the means for monitoring cardiac function monitors cardiac function of the heart of the patient according to the second sense mode, the means for monitoring cardiac function monitors fewer non-electrophysiological parameters of the patient compared to the first sense mode.

45. The system of claim 43, wherein the means for monitoring cardiac function monitors cardiac function of the heart of the patient according to the first sense mode by at least monitoring a non-electrophysiological parameter of the patient, the non-electrophysiological parameter comprising at least one of cardiovascular pressure, tissue perfusion, blood oxygen saturation levels, heart sound signals, respiratory rate, intrathoracic impedance, cardiac mechanical activity, muscle movement, ultrasonic signals, heart rate, body temperature, or acoustic signals indicative of cardiac mechanical activity.

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

determine whether a therapy module is delivering electrical stimulation to a tissue site within a patient;

control a sensing module to monitor cardiac function of a heart of the patient according to a first sense mode if the therapy module is delivering electrical stimulation to the tissue site; and

control a sensing module to monitor cardiac function of the heart of the patient according to a second sense mode if the therapy module is not delivering electrical stimulation to the tissue site, wherein the first and second sense modes monitor at least one different non-electrophysiological parameter of the patient.