DYNAMIC CRANIAL NERVE STIMULATION BASED ON BRAIN STATE DETERMINATION FROM CARDIAC DATA

• US 20100106217A1
• Filed: 10/24/2008
• Published: 04/29/2010
• Est. Priority Date: 10/24/2008
• Status: Active Grant

• Current Assignee: Flint Hills Scientific, LLC, LivaNova USA, Inc. (LivaNova Plc)
• Original Assignee: Flint Hills Scientific, LLC
• Inventors: Colborn, John C.
• Granted Patent: US 8,417,344 B2
• Time in Patent Office: Days
• US Class Current: 607/45
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/346 Analysis of electrocardiograms
• CPC Class Codes: A61N 1/36082 Cognitive or psychiatric applications, e.g. dementia or Alzheimer's disease
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362

Abstract

A method of treating a medical condition in a patient using an implantable medical device, comprising providing an electrical signal generator; providing at least a first electrode operatively coupled to the electrical signal generator and to a vagus nerve of the patient; sensing cardiac data of the patient; determining at least a first cardiac parameter based upon said cardiac data; setting at least a first value; declaring an unstable brain state of a patient from said at least a first cardiac parameter and said at least a first value; and adjusting the at least a first value. Also, a computer readable program storage device encoded with instructions that, when executed by a computer, performs the method. In addition, the implantable medical device used in the method.

Claims

1. An implantable medical device (IMD) to treat a medical condition in a patient, comprising:

an electrical signal generator;

at least a first electrode operatively coupled to the electrical signal generator and to a vagus nerve of the patient;

a cardiac data sensing module capable of sensing cardiac data from the patient;

an unstable brain state declaration module comprising a cardiac module capable of determining at least a first cardiac parameter based upon sensed cardiac data from the patient; and

a value setting module for setting at least a first value to be used by the unstable brain state declaration module;

wherein;

the unstable brain state declaration module is capable of declaring an unstable brain state of a patient from said at least a first cardiac parameter and said at least a first value, and the value setting module is capable of adjusting said at least a first value.

2. The implantable medical device of claim 1, wherein the cardiac module is capable of determining at least a second cardiac parameter based upon sensed cardiac data from the patient, and the unstable brain state declaration module is capable of declaring an unstable brain state of a patient from said at least a first cardiac parameter, said at least a second cardiac parameter, and said at least a first value.

3. The implantable medical device of claim 1, wherein the electrical signal generator is capable of generating and delivering at least a first electrical signal through at least the first electrode to the vagus nerve if an unstable brain state has not been declared, and generating and delivering at least a second electrical signal through at least the first electrode to the vagus nerve if an unstable brain state has been declared.

4. The implantable medical device of claim 1, wherein the value setting module is capable of adjusting at least the first value in response to a user request to adjust at least the first value.

5. The implantable medical device of claim 1, wherein the value setting module is capable of adjusting the at least a first value to render the unstable brain state declaration module less likely to declare an unstable brain state.

6. The implantable medical device of claim 1, wherein the value setting module is capable of adjusting the at least a first value to render the unstable brain state declaration module more likely to declare an unstable brain state.

7. The implantable medical device of claim 1, wherein the at least a first cardiac parameter is selected from the group consisting of an instantaneous heart rate, a moving average heart rate over a predetermined time period, a ratio of a first moving average heart rate over a first predetermined time period and a second moving average heart rate over a second predetermined time period, a rate of change of the patient'"'"'s heart rate, an elevation of the patient'"'"'s instantaneous heart rate above a baseline heart rate, a duration of an elevation of the patient'"'"'s heart rate above the patient'"'"'s baseline heart rate, a depression of the patient'"'"'s heart rate below the patient'"'"'s baseline heart rate, a duration of an elevation of a first moving average heart rate over a second moving average heart rate, an R-R interval, a PR segment interval, a PQ segment interval, a QRS interval, an ST segment interval, a statistical analysis heart parameter, a spectral analysis heart parameter, a fractal analysis heart parameter, an interbeat interval, the amplitude or magnitude of the P wave, Q wave, R wave, S wave, T wave, U wave, or any segment or interval between waves;

a change of the amplitude or magnitude of the wave or any segment or interval between waves;

or a rate of change of the amplitude or magnitude of the wave or any segment or interval between waves, and two or more thereof.

8. The implantable medical device of claim 1, wherein said unstable brain state declaration module further comprises a non-cardiac parameter detection module capable of detecting at least one non-cardiac parameter selected from the group consisting of an activity level of the patient, an output of an accelerometer, a catamenial cycle, the time of day, an indicator of the patient'"'"'s sleep state, an inclination of the patient'"'"'s body, a dilation of a pupil of the patient, the patient'"'"'s body temperature, the patient'"'"'s blood pressure, and the patient'"'"'s electroencephalogram (EEG),

wherein said value setting module is capable of setting at least a second value, and

wherein said unstable brain state declaration module is capable of declaring an unstable brain state of the patient from both said at least one non-cardiac parameter and said at least a second value.

9. The implantable medical device of claim 1, further comprising a memory capable of storing a timestamp associated with a declaration of an unstable brain state.

10. The implantable medical device of claim 9, wherein said value setting module is capable of adjusting the at least a first value based upon at least one factor selected from the group consisting of a timestamp at which a patient experienced an unstable brain state, cardiac data associated with a timestamp at which a patient experienced an unstable brain state, an activity level of the patient, an output of an accelerometer, a catamenial cycle, the time of day, an indicator of the patient'"'"'s sleep state, an inclination of the patient'"'"'s body, a dilation of a pupil of the patient, the patient'"'"'s body temperature, the patient'"'"'s blood pressure, and the patient'"'"'s electroencephalogram (EEG).

11. The implantable medical device of claim 8, further comprising a memory capable of storing said at least one non-cardiac parameter, and wherein said value setting module is capable of adjusting said at least a second value based upon at least one factor selected from the group consisting of a timestamp at which a patient experienced an unstable brain state, cardiac data associated with a timestamp at which a patient experienced an unstable brain state, an activity level of the patient, an output of an accelerometer, a catamenial cycle, the time of day, an indicator of the patient'"'"'s sleep, an inclination of the patient'"'"'s body, a dilation of a pupil of the patient, the patient'"'"'s body temperature, the patient'"'"'s blood pressure, and the patient'"'"'s electroencephalogram (EEG).

12. The implantable device of claim 9, wherein said value setting module is capable of analyzing a log of times at which a patient experiences an unstable brain state to determine at least a first period when the patient has an increased frequency of unstable brain states, and adjusting the at least a first value to render the unstable brain state declaration module more likely to declare an unstable brain state during said at least a first period.

13. The implantable device of claim 12, wherein the first period is less than one day.

14. A method of treating a medical condition in a patient using an implantable medical device, comprising:

providing an electrical signal generator,

providing at least a first electrode operatively coupled to the electrical signal generator and to a vagus nerve of the patient;

sensing cardiac data of the patient;

determining at least a first cardiac parameter based upon said cardiac data;

setting at least a first value;

declaring an unstable brain state of a patient from said at least a first cardiac parameter and said at least a first value; and

adjusting said at least a first value.

15. The method of claim 14, further comprising,

generating and applying a first electrical signal to the vagus nerve if an unstable brain state has not been declared, and

generating and applying a second electrical signal to the vagus nerve if an unstable brain state has been declared.

16. The method of claim 14, wherein sensing cardiac data comprises sensing at least one of a P wave, an Q wave, a QR complex, an R wave, an S wave, a QRS complex, a T wave, and a U wave, and wherein said at least a first cardiac parameter comprises at least one of an instantaneous heart rate, a moving average heart rate over a predetermined time period, a ratio of a first moving average heart rate over a first predetermined time period and a second moving average heart rate over a second predetermined time period, a rate of change of the patient'"'"'s heart rate, an elevation of the patient'"'"'s instantaneous heart rate above a baseline heart rate, a duration of an elevation of the patient'"'"'s heart rate above the patient'"'"'s baseline heart rate, a duration of an elevation of a first moving average heart rate over a second moving average heart rate, an R-R interval, a P-P interval, a PR segment interval, a PQ segment interval, a QRS interval, an ST segment interval, a statistical analysis heart parameter, a spectral analysis heart parameter, a fractal analysis heart parameter, the amplitude or magnitude of the P wave, Q wave, R wave, S wave, T wave, U wave, or any segment or interval between waves;

a change of the amplitude or magnitude of the wave or any segment or interval between waves;

or a rate of change of the amplitude or magnitude of the wave or any segment or interval between waves, and two or more thereof.

17. The method of claim 14, wherein adjusting the at least a first value occurs in response to a user request to adjust the first value.

18. The method of claim 14, wherein adjusting the at least a first value comprises rendering declaring an unstable brain state less likely.

19. The method of claim 14, wherein adjusting the at least a first value comprises rendering declaring an unstable brain state more likely.

20. The method of claim 14, further comprising storing a timestamp associated with declaring an unstable brain state.

21. The method of claim 20, further comprising storing a time series of the at least a first cardiac parameter.

22. The method of claim 20, wherein adjusting the at least a first value is based upon a plurality of said timestamps.

23. The method of claim 20, further comprising determining at least a first period when the patient has an increased frequency of unstable brain states, and adjusting the at least a first value to render declaring an unstable brain state more likely during said at least a first period.

24. A computer readable program storage device encoded with instructions that, when executed by a computer, performs a method of treating a medical condition in a patient using an implantable medical device, comprising:

sensing cardiac data of the patient;

determining at least a first cardiac parameter based upon said cardiac data;

setting at least a first value;

declaring an unstable brain state of a patient from said at least a first cardiac parameter and said at least a first value; and

adjusting said at least a first value.

25. The computer readable program storage device of claim 24, wherein the method further comprises:

if an unstable brain state is not declared, instructing an electrical signal generator to generate and deliver a first electrical signal through at least the first electrode to the vagus nerve of the patient, and

if an unstable brain state is declared, instructing an electrical signal generator to generate and deliver a second electrical signal through at least the first electrode to the vagus nerve of the patient.