US 11,786,732 B2
R-R interval analysis for ECG waveforms to assess autonomic response to vagus nerve stimulation
Imad Libbus, St. Paul, MN (US); Scott R. Stubbs, Maple Grove, MN (US); Scott Mazar, Woodbury, MN (US); Bruce KenKnight, Maple Grove, MN (US); and Badri Amurthur, Los Gatos, CA (US)
Assigned to LivaNova USA, Inc., Houston, TX (US)
Appl. No. 17/54,982
Filed by LivaNova USA, Inc., Houston, TX (US)
PCT Filed May 13, 2019, PCT No. PCT/US2019/031997
§ 371(c)(1), (2) Date Nov. 12, 2020,
PCT Pub. No. WO2019/222089, PCT Pub. Date Nov. 21, 2019.
Claims priority of provisional application 62/671,986, filed on May 15, 2018.
Prior Publication US 2021/0268286 A1, Sep. 2, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. A61N 1/36 (2006.01)
CPC A61N 1/36114 (2013.01) [A61N 1/36139 (2013.01)] 29 Claims
OG exemplary drawing
 
1. An assessment system for vagus nerve stimulation therapy treatment for congestive heart failure in a subject implanted with a neurostimulator configured to deliver a periodic stimulation signal having a plurality of ON-periods and OFF-periods, each ON-period being defined as a time between an initiating pulse and a terminating pulse of a plurality of stimulation pulses delivered to the subject, each OFF-period being defined as a time between consecutive ON-periods, the assessment system comprising:
a wand assembly in communication with the neurostimulator, the wand assembly configured to detect a delivery of the periodic stimulation signal from the neurostimulator to the subject and to generate a delivery detection signal indicating the detected delivery of the periodic stimulation signal;
a lead assembly configured to acquire an ECG signal of the subject over the plurality of ON-periods and OFF-periods;
a data acquisition system coupled to the wand and lead assemblies and configured to capture each of the delivery detection signal and the ECG signal; and
a processor and a non-transitory computer-readable memory storing instructions that, when executed by the processor, cause the assessment system to:
record the ECG signal over at least one successive pair of ON- and OFF-periods including, for each pair of ON- and OFF-periods, synchronizing a start of the recorded ECG signal using the delivery detection signal to provide a first portion of the recorded ECG signal corresponding to the ON-period and a second portion of the recorded ECG signal corresponding to the OFF-period;
determine a heart rate dynamic response from the ECG signal, including:
detecting each QRS complex in each of the first and second portions of the recorded ECG signal;
identifying each potential R-wave in each QRS complex in each of the first and second portions of the recorded ECG signal;
verifying each identified R-wave in each of the first and second portions of the recorded ECG signal; and
determining an R-R interval between each pair of successive verified R-waves;
determine an instantaneous heart rate for each determined R-R interval to determine heart rate dynamics for assessment of autonomic engagement in response to the vagus nerve stimulation therapy treatment; and
display the recorded ECG signal in real-time.