Controlled titration of neurostimulation therapy

• US 9,242,105 B2
• Filed: 05/02/2014
• Issued: 01/26/2016
• Est. Priority Date: 08/29/2006
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Brockway, Marina V., Libbus, Imad, Siejko, Krzysztof Z., Sweeney, Robert J.
• Primary Examiner(s): Gedeon, Brian T
• Application Number:
  US14/268,770
• Publication Number:
  US 20140243929A1
• Time in Patent Office: 634 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: A61B 5/02405 Determining heart rate variability
• CPC Class Codes: A61B 5/4035 Evaluating the autonomic nervous system
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362
• CPC Class Codes: A61N 1/36117 for treating hypertension
• CPC Class Codes: A61N 1/36139 with automatic adjustment
• CPC Class Codes: A61N 1/37264 Changing the program; Upgrading firmware
• CPC Class Codes: A61N 1/3727 characterised by the modulation technique
• CPC Class Codes: G16H 20/10 relating to drugs or medications, e.g. for ensuring correct administration to patients
• CPC Class Codes: G16H 20/40 relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture
• CPC Class Codes: G16H 40/67 for remote operation

Abstract

Described herein are methods and devices that utilize electrical neural stimulation to treat heart failure by modulating a patient'"'"'s autonomic balance in a manner that inhibits sympathetic activity and/or augments parasympathetic activity. Because other therapies for treating heart failure may also affect a patient'"'"'s autonomic balance, a device for delivering neural stimulation is configured to appropriately titrate such therapy in either an open-loop or closed-loop fashion.

Claims

1. An implantable device for delivering neurostimulation to a patient, comprising:

a pulse generator for outputting neurostimulation pulses and for connecting to one or more stimulation electrodes to deliver electrical stimulation to one or more selected neural sites the produce parasympathetic stimulation and/or sympathetic inhibition;

a controller connected to the pulse generator for controlling the output of neurostimulation pulses in accordance with a defined schedule that specifies the times of day the neurostimulation pulses are to be delivered and in accordance with one or more stimulation parameters;

a sensor interfaced to the controller for sensing a physiological variable reflective of a patient'"'"'s autonomic balance;

a telemetry unit interfaced to the controller, wherein the controller is programmed to receive medication dosage information via telemetry that includes the time or times of day that a medication affecting the patient'"'"'s autonomic balance is to be taken; and

,

wherein the controller is programmed to adjust the schedule for delivering neurostimulation in accordance with received medication dosage information after confirming that the medication has had its expected effect on the patient'"'"'s autonomic balance as reflected by the sensed physiological variable.

2. The device of claim 1 wherein the controller is further programmed to modify the one or more stimulation parameters in accordance with the medication dosage information.

3. The device of claim 1 wherein the controller is programmed to reduce the amount of neurostimulation delivered when the patient takes a dose of a beta-blocker.

4. The device of claim 1 wherein the controller is programmed to increase the amount of neurostimulation delivered when the patient takes a dose of a diuretic.

5. The device of claim 1 wherein the controller is programmed to receive medication dosage information from an electronic pill counter.

6. The device of claim 1

wherein the controller is programmed to adjust the amount of neurostimulation delivered in accordance with a determination of the patient'"'"'s autonomic balance.

7. The device of claim 6 wherein the controller is programmed to adjust the amount of neurostimulation delivered in accordance with the patient'"'"'s measured heart rate.

8. The device of claim 6 wherein the controller is programmed to:

measure and collect time intervals between successive intrinsic beats, referred to as a BB interval, and storing the collected intervals as a discrete BB interval signal, filter the BB interval signal into defined high and low frequency bands, and determine the signal power of the BB interval signal in each of the low and high frequency bands, referred to LF and HF, respectively; and

,

compute an LF/HF ratio and assess autonomic balance by comparing the LF/HF ratio to a specified threshold value; and

,

adjust the amount of neurostimulation delivered in accordance with the patient'"'"'s autonomic balance.

9. The device of claim 8 wherein the controller is programmed to assess autonomic balance in accordance with a measured activity level.

10. The device of claim 9 wherein the sensor is an accelerometer.

11. A method for delivering neurostimulation to a patient, comprising:

implanting an implantable device to deliver neurostimulation pulses to a selected neural site that produces parasympathetic stimulation and/or sympathetic inhibition;

programming the implantable device to deliver neurostimulation pulses in accordance with a defined schedule that specifies the times of day the neurostimulation pulses are to be delivered and in accordance with one or more stimulation parameters;

programming the implantable device to sense a physiological variable reflective of the patient'"'"'s autonomic balance;

programming the implantable device to receive medication dosage information via telemetry that includes the time or times of day that a medication affecting the patient'"'"'s autonomic balance is to be taken; and

,

programming the implantable device to adjust the schedule for delivering neurostimulation in accordance with received medication dosage information after confirming that the medication has had its expected effect on the patient'"'"'s autonomic balance as reflected by the sensed physiological variable.

12. The method of claim 11 further comprising programming the implantable device to modify the stimulation parameters in accordance with the medication dosage information.

13. The method of claim 11 wherein the selected neural site is the vagus nerve or a baroreceptor of a patient and further comprising programming the implantable device to reduce the amount of neurostimulation delivered when the patient takes a dose of a beta-blocker.

14. The method of claim 11 wherein the selected neural site is the vagus nerve or a baroreceptor of a patient and further comprising programming the implantable device to increase the amount of neurostimulation delivered when the patient takes a dose of a diuretic.

15. The method of claim 11 further comprising programming the implantable device to receive medication dosage information from an electronic pill counter.

16. The method of claim 11 further comprising:

programming the implantable device to adjust the amount of neurostimulation delivered in accordance with a determination of the patient'"'"'s autonomic balance.

17. The method of claim 11 further comprising programming the implantable device to adjust the amount of neurostimulation delivered in accordance with the patient'"'"'s measured heart rate.

18. The method of claim 11 further comprising programming the implantable device to:

measure and collect time intervals between successive intrinsic beats, referred to as a BB interval, and storing the collected intervals as a discrete BB interval signal, filter the BB interval signal into defined high and low frequency bands, and determine the signal power of the BB interval signal in each of the low and high frequency bands, referred to LF and HF, respectively; and

,

compute an LF/HF ratio and assess autonomic balance by comparing the LF/HF ratio to a specified threshold value; and

,

adjust the amount of neurostimulation delivered in accordance with the patient'"'"'s autonomic balance.

19. The method of claim 18 further comprising programming the implantable device to assess autonomic balance in accordance with a measured activity level.

20. The method of claim 19 further comprising measuring activity level with an accelerometer.