Implantable neurostimulator-implemented method for managing techyarrhythmia through vagus nerve stimulation

• US 10,195,437 B2
• Filed: 09/18/2017
• Issued: 02/05/2019
• Est. Priority Date: 11/09/2012
• Status: Active Grant

• Current Assignee: LivaNova USA, Inc. (LivaNova Plc)
• Original Assignee: Cyberonics, Inc
• Inventors: Libbus, Imad, Amurthur, Badri, KenKnight, Bruce H.
• Primary Examiner(s): Evanisko, George
• Application Number:
  US15/706,946
• Publication Number:
  US 20180001091A1
• Time in Patent Office: 505 Days
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/283 Invasive
• CPC Class Codes: A61B 5/352 Detecting R peaks, e.g. for synchronising diagnostic apparatus; Estimating R-R interval
• CPC Class Codes: A61B 5/363 Detecting tachycardia or bradycardia
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence
• CPC Class Codes: A61N 1/36053 adapted for vagal stimulation A61N1/36114 takes precedence
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362
• CPC Class Codes: A61N 1/36139 with automatic adjustment
• CPC Class Codes: A61N 1/3621 for treating or preventing abnormally high heart rate

Abstract

An implantable neurostimulator-implemented method for managing tachyarrhythmias through vagus nerve stimulation is provided. An implantable neurostimulator, including a pulse generator, is configured to deliver electrical therapeutic stimulation in a manner that results in creation and propagation (in both afferent and efferent directions) of action potentials within neuronal fibers of a patient'"'"'s cervical vagus nerve. Operating modes of the pulse generator are stored. A maintenance dose of the electrical therapeutic stimulation is delivered to the vagus nerve via the pulse generator to restore cardiac autonomic balance through continuously-cycling, intermittent and periodic electrical pulses. A restorative dose of the electrical therapeutic stimulation is delivered to prevent initiation of or disrupt tachyarrhythmia through periodic electrical pulses delivered at higher intensity than the maintenance dose. The patient'"'"'s normative physiology is monitored via a physiological sensor, and upon sensing a condition indicative of tachyarrhythmia, is switched to delivering the restorative dose to the vagus nerve.

Claims

1. An implantable neurostimulator for managing tachyarrhythmias through vagus nerve stimulation, comprising:

a pulse generator configured to couple to an electrode assembly and to generate electrical stimulation;

a processor configured to receive physiological data from a physiological sensor; and

a memory having instructions stored thereon that, when executed by the processor, cause the processor to;

define a maintenance dose of the electrical stimulation; and

define a restorative dose of the electrical stimulation comprising electrical pulses delivered at higher intensity than the maintenance dose;

record the patient'"'"'s normative physiology in the memory;

assign more statistical weight to recently recorded normative physiology and less statistical weight to older recorded normative physiology;

determine a weighted statistical average of the patient'"'"'s normative physiology recorded in the memory based on the assigned statistical weights;

define a condition of tachyarrhythmia as triggered when the weighted statistical average exceeds a physiological threshold of arrhythmogenesis;

deliver the maintenance dose via the pulse generator to the electrode assembly, prior to delivering the restorative dose, prior to sensing the condition of tachyarrhythmia, and independent of cardiac cycle;

monitor a patient'"'"'s normative physiology to sense the condition of tachyarrhythmia via the processor receiving the physiological data;

upon sensing the condition of tachyarrhythmia, switch from delivering the maintenance dose to delivering the restorative dose to the electrode assembly via the pulse generator;

upon delivering the restorative dose, monitor the patient'"'"'s normative physiology to determine whether the condition of tachyarrhythmia is continuing; and

upon sensing that the condition of tachyarrhythmia is not recurring, switch from delivering the restorative dose to delivering the maintenance dose to the electrode assembly via the pulse generator.

2. The implantable neurostimulator of claim 1, wherein the instructions further cause the processor to:

during monitoring, confirm that the patient'"'"'s normative physiology comprises a normal sinus rhythm; and

upon departure from the normal sinus rhythm, modify the operating mode of the pulse generator based on whether the departure signifies an increase, decrease, or entrainment of cardiac rhythm.

3. The implantable neurostimulator of claim 1, wherein the instructions further cause the processor to:

specify one or more physiological markers of abnormally fast sinus rhythm as indicative of tachyarrhythmia;

monitor the patient'"'"'s sinus rhythm via the physiological sensor; and

upon sensing at least one physiological marker of abnormally fast sinus rhythm, trigger delivery of the restorative dose.

4. The implantable neurostimulator of claim 1, further comprising the physiological sensor, wherein said physiological sensor comprises:

a leadless heart rate sensor coupled to the pulse generator to sense a heart rate of the patient in response to the electrical stimulation,

wherein the instructions further cause the processor to;

specify a threshold heart rate as indicative of tachyarrhythmia;

monitor the heart rate of the patient through the leadless heart rate sensor; and

upon sensing the heart rate of the patient is above the threshold heart rate, trigger the delivery of the restorative dose.

5. A non-transitory computer-readable medium comprising instructions executable by a processor of an implantable medical device to perform operations, the implantable medical device, further comprising a pulse generator and a physiological sensor, the operations comprising:

defining a maintenance dose of electrical stimulation;

defining a restorative dose of the electrical stimulation comprising electrical pulses delivered at higher intensity than the maintenance dose;

recording the patient'"'"'s normative physiology;

assigning more statistical weight to recently recorded normative physiology and less statistical weight to older recorded normative physiology;

determining a weighted statistical average of the patient'"'"'s recorded normative physiology based on the assigned statistical weights;

defining a condition of tachyarrhythmia as triggered when the weighted statistical average exceeds a physiological threshold of arrhythmogenesis;

delivering, using the pulse generator, the maintenance dose, prior to delivering the restorative dose, prior to sensing the condition of tachyarrhythmia, and independent of cardiac cycle;

monitoring a patient'"'"'s normative physiology to sense the condition of tachyarrhythmia via the physiological sensor;

upon sensing the condition of tachyarrhythmia, switching from delivering the maintenance dose to delivering the restorative dose;

upon delivering the restorative dose, monitoring the patient'"'"'s normative physiology to determine whether the condition of tachyarrhythmia is continuing; and

upon sensing that the condition of tachyarrhythmia is not recurring, switching from delivering the restorative dose to delivering the maintenance dose.

6. The non-transitory computer-readable medium of claim 5, wherein the operations further comprise:

during monitoring, confirming that the patient'"'"'s normative physiology comprises a normal sinus rhythm; and

upon departure from the normal sinus rhythm, modifying the operating mode of the pulse generator based on whether the departure signifies an increase, decrease, or entrainment of cardiac rhythm.

7. The non-transitory computer-readable medium of claim 5, wherein the operations further comprise:

specifying one or more physiological markers of abnormally fast sinus rhythm as indicative of tachyarrhythmia;

monitoring the patient'"'"'s sinus rhythm via the physiological sensor; and

upon sensing at least one physiological marker of abnormally fast sinus rhythm, triggering delivery of the restorative dose.

8. The non-transitory computer-readable medium of claim 5, wherein the operations further comprise specifying a threshold heart rate as indicative of tachyarrhythmia;

wherein monitoring the patient'"'"'s normative physiology to sense the condition of tachyarrhythmia comprises monitoring the heart rate of the patient; and

wherein delivery of the restorative dose is triggered in response to sensing the heart rate of the patient is above the threshold heart rate.

9. A method for managing tachyarrhythmias through vagus nerve stimulation, comprising:

defining a maintenance dose of electrical stimulation; and

defining a restorative dose of the electrical stimulation comprising electrical pulses delivered at higher intensity than the maintenance dose;

recording the patient'"'"'s normative physiology;

assigning more statistical weight to recently recorded normative physiology and less statistical weight to older recorded normative physiology;

determining a weighted statistical average of the patient'"'"'s recorded normative physiology based on the assigned statistical weights;

defining the condition of tachyarrhythmia as triggered when the weighted statistical average exceeds a physiological threshold of arrhythmogenesis;

delivering, using the pulse generator, the maintenance dose, prior to delivering the restorative dose, prior to sensing the condition of tachyarrhythmia, and independent of cardiac cycle;

monitoring, using a sensor, a patient'"'"'s normative physiology to sense the condition of tachyarrhythmia;

upon sensing the condition of tachyarrhythmia, switching from delivering the maintenance dose to delivering the restorative dose;

upon delivering the restorative dose, monitoring the patient'"'"'s normative physiology to determine whether the condition of tachyarrhythmia is continuing; and

upon sensing that the condition of tachyarrhythmia is not recurring, switching from delivering the restorative dose to delivering the maintenance dose.

10. The method of claim 9, further comprising:

during monitoring, confirming that the patient'"'"'s normative physiology comprises a normal sinus rhythm; and

upon departure from the normal sinus rhythm, modifying the operating mode of the pulse generator based on whether the departure signifies an increase, decrease, or entrainment of cardiac rhythm.

11. The method of claim 9, further comprising specifying a threshold heart rate as indicative of tachyarrhythmia,

wherein monitoring the patient'"'"'s normative physiology to sense the condition of tachyarrhythmia comprises monitoring the heart rate of the patient, and

wherein delivery of the restorative dose is triggered in response to sensing the heart rate of the patient is above the threshold heart rate.