Systems and methods for delivering vagal therapy

Patent metadata

Field	Value
Publication number	US-2016101289-A1
Application number	US-201514881574-A
Country	US
Kind code	A1
Filing date	Oct 13, 2015
Priority date	Oct 13, 2014
Publication date	Apr 14, 2016
Grant date	—

Abstract

A method may include delivering autonomic neural stimulation (ANS) therapy, including delivering stimulation pulses to evoke physiological responses. The method may further include recording physiological parameter values, including recording first population data, the first population data including evoked response (ER) values corresponding to the evoked physiological responses, and recording second population data, the second population data including reference values that include no effect (NE) values corresponding to times without an evoked physiological response. The method may further include quantifying a relationship between the first population data and the second population data, and analyzing the quantified relationship for a signature to indicate if the stimulation pulses are evoking desired physiological responses.

First claim

What is claimed is:

1 . A method, comprising:
delivering autonomic neural stimulation (ANS) therapy, including delivering stimulation pulses to evoke physiological responses; recording physiological parameter values, including:
recording first population data, the first population data including evoked response (ER) values corresponding to the evoked physiological responses; and
recording second population data, the second population data including reference values that include no effect (NE) values corresponding to times without an evoked physiological response;
quantifying a relationship between the first population data and the second population data; and analyzing the quantified relationship for a signature to indicate if the stimulation pulses are evoking desired physiological responses.

2 . The method of claim 1 , wherein the ER values include:
stimulation effect (SE) values corresponding to direct responses to delivered stimulation pulses; or reflex effect (RE) values corresponding to reflex responses after delivered stimulation pulses; or both SE values and RE values.

3 . The method of claim 1 , wherein delivering ANS therapy includes delivering bursts of neural stimulation pulses, the NE values including values during times between successive bursts of neural stimulation pulses.

4 . The method of claim 1 , wherein delivering ANS therapy includes delivering a first therapy with at least one neural stimulation pulse timed to a cardiac cycle, and delivering a second therapy that includes delivering bursts of neural stimulation pulses where each neural stimulation burst includes a plurality of neural stimulation pulses and successive neural stimulation bursts are separated by a time without neural stimulation pulses, the ER and NE values corresponding to times during delivery of the second therapy,
the method further including determining a pulse amplitude for pulses in the second therapy using the group of ER scores, and using the pulse amplitude for pulses in the first therapy.

5 . The method of claim 1 , further comprising interrupting delivery of the ANS therapy to record the NE values for the second population data.

6 . The method of claim 1 , wherein the physiological parameter values include at least one of: heart rate values or heart rate variability values.

7 . The method of claim 1 , wherein the physiological parameter values include at least one of: respiratory values or respiratory variability values.

8 . The method of claim 1 , wherein recording physiological parameter values includes recording electrocardiograms (ECG), and quantifying the relationship between the first population data and the second population data includes calculating a change in PQRS morphology.

9 . The method of claim 1 , wherein quantifying the relationship between the first population data and the second population data includes:
Z-scoring groups of recorded physiological parameter values to obtain Z-scores for each of the groups; or T-scoring groups of recorded physiological parameter values to obtain T-scores for each of the groups.

10 . A method, comprising:
delivering intermittent vagal nerve stimulation (VNS) therapy, the intermittent VNS therapy including a plurality of stimulation bursts, each stimulation burst including a plurality of neural stimulation pulses, and successive neural stimulation bursts are separated by a time without neural stimulation pulses; recording physiological parameter values, including:
recording first population data, the first population data including evoked response (ER) values corresponding to the evoked physiological responses to stimulation bursts; and
recording second population data, the second population data including reference values that include no effect (NE) values corresponding to physiological parameter values that are not evoked physiological responses to stimulation bursts;
calculating an evoked response metric (ERM) to quantify a relationship between the first population data and the second population data; determining if the stimulation bursts are evoking desired physiological responses, wherein determining includes analyzing the ERM to indicate if the stimulation bursts are evoking the desired physiological responses; and when it is determined that the stimulation bursts are not evoking the desired ERM, adjusting the intermittent VNS therapy to produce the desired ERM.

11 . The method of claim 10 , wherein recording physiological parameter values includes recording R-R values.

12 . The method of claim 10 , wherein:
the ER values in the first population data include stimulation effect (SE) values corresponding to direct responses to stimulation bursts; and calculating the ERM to quantify the relationship between the first population data and the second population data includes analyzing for a SE signature.

13 . The method of claim 10 , wherein:
the ER values in the first population data include reflex effect (RE) values corresponding to reflex responses after stimulation bursts; and calculating the ERM to quantify the relationship between the first population data and the second population data includes analyzing for a RE signature.

14 . The method of claim 10 , wherein:
the ER values in the first population data include both stimulation effect (SE) values corresponding to direct responses to stimulation bursts and reflex effect (RE) values corresponding to reflex responses after stimulation bursts; and calculating the ERM to quantify the relationship between the first population data and the second population data includes analyzing for a SE signature and for a RE signature.

15 . The method of claim 10 , wherein the reference values only include NE values.

16 . The method of claim 10 , wherein the reference values include both ER values and NE values.

17 . The method of claim 10 , wherein a group of recorded physiological parameter values correspond to an interval of time less than two burst periods, the group including at least some data from the first population data and at least some data from the second population data, and calculating the ERM to quantify the relationship between the first population data and the second population data includes calculating the ERM for the group of recorded physiological parameter values.

18 . The method of claim 10 , wherein recording, z-scoring, and analyzing are part of VNS therapy response extraction process, the method further comprising enabling or disabling at least part of the VNS therapy response process based on a detected condition.

19 . The method of claim 10 , further comprising correlating the ERM to a patient status or a patient condition, wherein analyzing the ERM includes analyzing the correlation of the ERM to the patient status or the patient condition.

20 . The method of claim 10 , wherein adjusting the intermittent VNS therapy to produce the desired ERM includes changing an amplitude of the neural stimulation pulses, the method further including further modifying other stimulation parameters of the intermittent VNS therapy to maintain a tolerable neural stimulation dose.

Assignees

• Cardiac Pacemakers Inc

Inventors

• Stolen Craig
• Agarwal Rahul
• Wold Nicholas
• Ruble Stephen B

Classifications

• A61N1/36114 Primary

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

• A61B5/4848

  Monitoring or testing the effects of treatment, e.g. of medication · CPC title

• A61M2205/18

  with alarm · CPC title

• A61M5/44

  having means for cooling or heating the devices or media · CPC title

• A61M2205/60

  with identification means · CPC title