Evaluation of vagus nerve stimulation using heart rate variability analysis

Patent metadata

Field	Value
Publication number	US-2019358456-A1
Application number	US-201916422746-A
Country	US
Kind code	A1
Filing date	May 24, 2019
Priority date	May 25, 2018
Publication date	Nov 28, 2019
Grant date	—

Abstract

An implantable vagus nerve stimulation (VNS) system includes a sensor configured to measure ECG data for a patient, a stimulation subsystem configured to deliver VNS to the patient, and a control system configured to perform a heart rate variability analysis with the ECG data. In some aspects, performing the heart rate variability analysis includes measuring R-R intervals between successive R-waves for the ECG data measured during a stimulation period and a baseline period, plotting each R-R interval against an immediately preceding R-R interval for each of the stimulation period and the baseline period, and determining at least one of a standard deviation from an axis of a line perpendicular to an identity line for each of the stimulation period plot and the baseline period plot or a centroid of each of the stimulation period plot and the baseline period plot.

First claim

What is claimed is:

1 . An implantable vagus nerve stimulation (VNS) system, comprising:
a sensor configured to measure ECG data for a patient; a stimulation subsystem configured to deliver VNS to the patient, wherein the VNS is delivered according to a duty cycle comprising an ON period during which a VNS dose is applied and an OFF period during which the VNS dose is suspended; and a control system configured to perform a heart rate variability analysis with the ECG data by:
measuring R-R intervals between successive R-waves for the ECG data measured during at least a portion of the ON period and at least a portion of the OFF period, wherein the at least a portion of the ON period is a stimulation period and the at least a portion of the OFF period is a baseline period; and
plotting each R-R interval against an immediately successive R-R interval for each of the stimulation period and the baseline period.

2 . The implantable VNS system of claim 1 , wherein the heart rate variability analysis is a Poincaré analysis.

3 . The implantable VNS system of claim 1 , wherein the control system is further configured to perform the heart rate variability analysis by determining, based on the plot, at least one of:
a standard deviation from an axis of a line perpendicular to an identity line for each of the stimulation period plot and the baseline period plot; or a centroid of each of the stimulation period plot and the baseline period plot.

4 . The implantable VNS system of claim 3 , wherein performing the heart rate variability analysis comprises determining the centroid of each of the stimulation period plot and the baseline period plot, and wherein the control system is further configured to:
determine a distance between the centroids of the stimulation period plot and the baseline period plot; and compare the distance to a threshold value.

5 . The implantable VNS system of claim 4 , wherein the control system is further configured to, in response to the distance being less than the threshold value, perform at least one of:
sending an alert to a physician of the patient; or modifying an intensity of the VNS dose applied to the patient.

6 . The implantable VNS system of claim 1 , wherein the control system is further configured to control the stimulation subsystem to increase the VNS dose delivered to the patient according to a titration schedule.

7 . The implantable VNS system of claim 6 , wherein the control system is configured to perform the heart rate variability analysis in response to an increase in the VNS dose.

8 . The implantable VNS system of claim 1 , wherein the control system is configured to perform the heart rate variability analysis periodically.

9 . The implantable VNS system of claim 8 , wherein the control system is configured to prepare periodic reports for a physician of the patient based on the periodic heart rate variability analysis.

10 . A vagus nerve stimulation (VNS) system, comprising:
an external programmer; and an implantable system comprising:
a sensor configured to measure ECG data for a patient and transmit the ECG data to the external programmer; and
a stimulation subsystem configured to deliver VNS to a patient, wherein the VNS is delivered according to a duty cycle comprising an ON period during which a VNS dose is applied and an OFF period during which the VNS dose is suspended;
wherein the external programmer is configured to:
receive the ECG data from the implantable system; and
perform a heart rate variability analysis with the ECG data by:
measuring R-R intervals between successive R-waves for the ECG data measured during at least a portion of the ON period and at least a portion of the OFF period, wherein the at least a portion of the ON period is a stimulation period and the at least a portion of the OFF period is a baseline period; and
plotting each R-R interval against an immediately successive R-R interval for each of the stimulation period and the baseline period.

11 . The implantable VNS system of claim 10 , wherein the heart rate variability analysis is a Poincaré analysis.

12 . The VNS system of claim 10 , wherein the external programmer is further configured to perform the heart rate variability analysis by determining, based on the plot, at least one of:
a standard deviation from an axis of a line perpendicular to an identity line for each of the stimulation period plot and the baseline period plot; or a centroid of each of the stimulation period plot and the baseline period plot.

13 . The VNS system of claim 12 , wherein performing the heart rate variability analysis comprises determining the centroid of each of the stimulation period plot and the baseline period plot, and wherein the external programmer is further configured to:
determine a distance between the centroids of the stimulation period plot and the baseline period plot; and compare the distance to a threshold value.

14 . The VNS system of claim 13 , wherein the external programmer is further configured to, in response to the distance being less than the threshold value:
display an alert; or transmit a command to the implantable system to increase an intensity of the VNS dose applied to the patient.

15 . The VNS system of claim 10 , wherein the external programmer is further configured to display the stimulation period plot and the baseline period plot.

16 . The VNS system of claim 10 , wherein the sensor is configured to transmit the ECG data to the external programmer in real-time and the external programmer is configured to receive the ECG data from the implantable system and perform the heart rate variability analysis in real-time.

17 . A vagus nerve stimulation (VNS) system, comprising:
a local telemetry device; and an implantable system, comprising:
a sensor configured to measure ECG data for a patient and transmit the ECG data to the local telemetry device; and
a stimulation subsystem configured to deliver VNS to the patient, wherein the VNS is delivered according to a duty cycle comprising an ON period during which a VNS dose is applied and an OFF period during which the VNS dose is suspended;
wherein the local telemetry device is configured to:
receive the ECG data from the implantable system; and
perform a heart rate variability analysis with the ECG data by:
measuring R-R intervals between successive R-waves for the ECG data measured during at least a portion of the ON period and at least a portion of the OFF period, wherein the at least a portion of the ON period is a stimulation period and the at least a portion of the OFF period is a baseline period; and
plotting each R-R interval against an immediately preceding R-R interval for each of the stimulation period and the baseline period.

18 . The VNS system of claim 17 , wherein the heart rate variability analysis is a Poincaré analysis.

19 . The VNS system of claim 17 , wherein the local telemetry device is further configured to perform the heart rate variability analysis by determining, based on the plot, at least one of:
a standard deviation from an axis of a line perpendicular to an identity line for each of the stimulation period plot and the baseline period plot; or a centroid of each of the stimulation period plot and the baseline period plot.

20 . The VNS system of claim 17 , wherein the local telemetry device is configured to perform the heart rate variability analysis periodically, and wherein the local telemetry device is configured to pre

Assignees

• Livanova Usa Inc

Inventors

• Libbus Imad
• Nearing Bruce D
• Amurthur Badri
• Kenknight Bruce H
• Verrier Richard L

Classifications

• A61B5/4836

  Diagnosis combined with treatment in closed-loop systems or methods (A61B5/0036 takes precedence) · CPC title

• A61N1/36171

  Frequency · CPC title

• A61B5/02405

  Determining heart rate variability · CPC title

• A61N1/36114 Primary

  Cardiac control, e.g. by vagal stimulation (stimulating the heart A61N1/362) · CPC title

• A61N1/3616

  Voltage density or current density · CPC title