Granted Patent B2

US 11,298,543 · App. 16/234,097 · Granted Apr 12, 2022

Inventors: Imad Libbus (St. Paul, MN); Badri Amurthur (Los Gatos, CA); Bruce H. KenKnight (Maple Grove, MN); Jeffrey L. Ardell (Johnson City, TN)

Assignees: LivaNova USA, Inc.; East Tennessee State University

A61N1/36114A61N1/3615A61N1/36053A61N1/36135A61N1/36139A61N1/37217A61N1/37264

Abstract

Claims (58)

1. A neurostimulation system, comprising:

an electrode assembly; and

a neurostimulator coupled to the electrode assembly, the neurostimulator comprising:

a control circuit; and

a memory operably coupled to the control circuit and comprising instructions that, when executed by the control circuit, cause the control circuit to:

deliver a first plurality of stimulation signals having a first frequency to a patient via the electrode assembly;

detect a transition heart rate response corresponding to a neural fulcrum zone responsive to a first subset of the first plurality of stimulation signals, the transition heart rate response being between a heart rate associated with a tachycardia condition and a heart rate associated with a bradycardia condition;

detect that delivering the first subset of stimulation signals does not produce a predetermined level of change in the heart rate of the patient;

deliver a second plurality of stimulation signals having a second frequency to the patient via the electrode assembly, the second frequency being greater than the first frequency;

detect the transition heart rate response corresponding to the neural fulcrum zone responsive to a second subset of the second plurality of stimulation signals;

detect that delivering the second subset of stimulation signals does produce the predetermined level of change in the heart rate of the patient; and

deliver the second subset of stimulation signals to the patient via the electrode assembly.

2. The neurostimulation system of claim 1 , wherein each of the first plurality of stimulation signals comprises an output current amplitude, a pulse width, a duty cycle, and the first frequency; and

wherein each of the second plurality of stimulation signals comprises an output current amplitude, a pulse width, a duty cycle, and the second frequency.

3. The neurostimulation system of claim 1 , wherein the instructions cause the control circuit to:

deliver the first plurality of stimulation signals having the first frequency by increasing an intensity of the first plurality of stimulation signals from one signal to a next signal; and

detect the transition heart rate response responsive to the first subset of the first plurality of stimulation signals based on the increase of the intensity of the first plurality of stimulation signals from one signal to the next signal.

4. The neurostimulation system of claim 3 , wherein the instructions cause the control circuit to increase the intensity of the first plurality of stimulation signals from one signal to the next signal by increasing at least one of an output current amplitude, a pulse width, or a duty cycle from one signal to the next signal.

5. The neurostimulation system of claim 3 , wherein the instructions cause the control circuit to:

deliver the second plurality of stimulation signals having the second frequency by increasing an intensity of the second plurality of stimulation signals from one signal to a next signal; and

detect the transition heart rate response responsive to the second subset of the second plurality of stimulation signals based on the increase of the intensity of the second plurality of stimulation signals from one signal to the next signal.

6. The neurostimulation system of claim 5 , wherein the instructions cause the control circuit to increase the intensity of the second plurality of stimulation signals from one signal to the next signal by increasing at least one of an output current amplitude, a pulse width, or a duty cycle from one signal to the next signal.

7. The neurostimulation system of claim 1 , wherein the transition heart rate response is a 0% to 5% heart rate reduction from a baseline heart rate.

8. A method of operating a neurostimulator coupled to an electrode assembly, comprising:

delivering a first plurality of stimulation signals having a first frequency to a patient via the electrode assembly;

detecting a transition heart rat response corresponding to a neural fulcrum zone responsive to a first subset of the first plurality of stimulation signals, the transition heart rate response being between a heart rate associated with a tachycardia condition and a heart rate associated with a bradycardia condition;

detecting that delivering the first subset of stimulation signals does not produce a predetermined level of change in the heart rate of the patient;

delivering a second plurality of stimulation signals having a second frequency to the patient via the electrode assembly, the second frequency being greater than the first frequency;

detecting the transition heart rate response corresponding to the neural fulcrum zone responsive to a second subset of the second plurality of stimulation signals;

detecting that delivering the second subset of stimulation signals does produce the predetermined level of change in the heart rate of the patient; and

delivering the second subset of stimulation signals to the patient via the electrode assembly.

9. The method of claim 8 , wherein each of the first plurality of stimulation signals comprises an output current amplitude, a pulse width, a duty cycle, and the first frequency; and

wherein each of the second plurality of stimulation signals comprises an output current amplitude, a pulse width, a duty cycle, and the second frequency.

10. The method of claim 8 , wherein delivering the first plurality of stimulation signals having the first frequency comprises increasing an intensity of the first plurality of stimulation signals from one signal to a next signal; and

wherein detecting the transition heart rate response responsive to the first subset of the first plurality of stimulation signals is based on increasing the intensity of the first plurality of stimulation signals from one signal to the next signal.

11. The method of claim 10 , wherein increasing the intensity of the first plurality of stimulation signals from one signal to the next signal comprises increasing at least one of an output current amplitude, a pulse width, or a duty cycle from one signal to the next signal.

12. The method of claim 10 , wherein delivering the second plurality of stimulation signals having the second frequency comprises increasing an intensity of the second plurality of stimulation signals from one signal to a next signal; and

wherein detecting the transition heart rate response responsive to the second subset of the second plurality of stimulation signals is based on increasing the intensity of the second plurality of stimulation signals from one signal to the next signal.

13. The method of claim 12 , wherein increasing the intensity of the second plurality of stimulation signals from one signal to the next signal comprises increasing at least one of an output current amplitude, a pulse width, or a duty cycle from one signal to the next signal.

14. The method of claim 8 , wherein the transition heart rate response is a 0% to 5% heart rate reduction from a baseline heart rate.

15. A memory coupled to a processor and comprising instructions that, when executed by the processor, cause the processor to:

deliver a first plurality of stimulation signals having a first frequency to a patient via an electrode assembly;

detect a transition heart rate response corresponding to a neural fulcrum zone responsive to a first subset of the first plurality of stimulation signals, the transition heart rate response between a heart rate associated with a bradycardia condition;

detect that delivering the first subset of stimulation signals does not produce a predetermined level of change in the heart rate of the patient;

deliver a second plurality of stimulation signals having a second frequency to the patient via the electrode assembly, the second frequency being greater than the first frequency;

detect the transition heart rate response corresponding to the neural fulcrum zone responsive to the second subset of the second plurality of stimulation signals;

detect that delivering the second subset of stimulation signals does produce the predetermined level of change in the heart rate of the patient; and

deliver the second subset of stimulation signals to the patient via the electrode assembly.

16. The memory of claim 15 , wherein each of the plurality of stimulation signals comprises an output current amplitude, a pulse width, a duty cycle, and the first frequency; and

wherein each of the second plurality of stimulation signals comprises an output current amplitude, a pulse width, a duty cycle, and the second frequency.

17. The memory of claim 15 , wherein the instructions cause the processor to:

deliver the first plurality of stimulation signals having the first frequency by increasing an intensity of the first plurality of stimulation signals from one signal to a next signal; and

detect the transition heart rate response responsive to the first subset of the first plurality of stimulation signals based on the increase of the intensity of the first plurality of stimulation signals from one signal to the next signal.

18. The memory of claim 17 , wherein the instructions cause the processor to increase the intensity of the first plurality of stimulation signals from one signal to the next signal by increasing at least one of an output current amplitude, a pulse width, or a duty cycle from one signal to the next signal.

19. The memory of claim 17 , wherein the instructions cause the processor to:

deliver the second plurality of stimulation signals having the second frequency by increasing an intensity of the second plurality of stimulation signals from one signal to a next signal; and

detect the transition heart rate response responsive to the second subset of the second plurality of stimulation signals based on the increase of the intensity of the second plurality of stimulation signals from one signal to the next signal.

20. The memory of claim 15 , wherein the transition heart rate response is a 0% to 5% heart rate reduction from a baseline heart rate.

Assignments (8)