Electrogram-based control of cardiac resynchronization therapy

Patent metadata

Field	Value
Publication number	US-2017340887-A1
Application number	US-201715610231-A
Country	US
Kind code	A1
Filing date	May 31, 2017
Priority date	May 31, 2016
Publication date	Nov 30, 2017
Grant date	—

Abstract

In some examples, controlling delivery of CRT includes delivering ventricular pacing according to a sequence of different values of at least one of A-V delay or V-V delay, and acquiring one or more electrograms from respective vectors. For each of the different values of the at least one of A-V delay or V-V delay, at least one of a QRS amplitude or a QRS area may be determined based on the one or more electrograms, and a target change in QRS amplitude or QRS area between adjacent ones of the values of the at least one of A-V delay or V-V delay of the sequence may be identified. In response to the identification of the target change, the implantable medical device may deliver the ventricular pacing at a value of the at least one of A-V delay or V-V delay determined based on the identification to provide CRT.

First claim

1 . A method for controlling delivery of cardiac resynchronization therapy (CRT) by an implantable medical device of a medical device system, the method comprising:
by one or more processors of the medical device system:
controlling the implantable medical device to deliver ventricular pacing according to a sequence of different values of at least one of A-V delay or V-V delay;
during the delivery of ventricular pacing according to the sequence, acquiring one or more electrograms, each of the one or more electrograms from a respective one of a plurality of vectors formed by a plurality of electrodes of the medical device system;
for each of the different values of the at least one of A-V delay or V-V delay, determining at least one of a QRS amplitude or a QRS area based on the one or more electrograms;
identifying a target change in QRS amplitude or QRS area between adjacent ones of the values of the at least one of A-V delay or V-V delay of the sequence; and
in response to the identification of the target change, controlling the implantable medical device to deliver the ventricular pacing at a value of the at least one of A-V delay or V-V delay determined based on the identification of the target change to provide CRT.

2 . The method of claim 1 , wherein the target change in QRS amplitude or QRS area indicates fusion occurring between right and left ventricles.

3 . The method of claim 1 , wherein the target change in QRS amplitude or QRS area comprises a decrease in QRS amplitude.

4 . The method of claim 1 , wherein controlling the implantable medical device to deliver the ventricular pacing according to the sequence of different values of at least one of A-V delay or V-V delay comprises controlling the implantable medical device to deliver left-ventricular pacing according to a sequence of different values of A-LV delay, and wherein controlling the implantable medical device to deliver the ventricular pacing at the value of the at least one of A-V delay or V-V delay determined based on the identification of the target change comprises controlling the implantable medical device to deliver LV fusion pacing at a value of an A-LV delay determined based on the identification of the target change.

5 . The method of claim 1 , wherein controlling the implantable medical device to deliver the ventricular pacing at the value of the at least one of A-V delay or V-V delay determined based on the identification of the target change comprises controlling the implantable medical device to deliver the ventricular pacing at the shorter of the adjacent ones of the values of the at least one of A-V delay or V-V delay of the sequence.

6 . The method of claim 1 , wherein acquiring the one or more electrograms comprises acquiring two electrograms, each of the electrograms acquired from a respective one of two vectors, the method further comprising determining, by the one or more processors, a two-dimensional vectorcardiogram from the two electrograms, wherein determining the at least one of the QRS amplitude or the QRS area based on the one or more electrograms comprises determining the at least one of the QRS amplitude or the QRS area based on the two-dimensional vectorcardiogram.

7 . The method of claim 6 , wherein the electrograms are bipolar electrograms, and each of the two vectors includes a first pole proximate the right ventricle and a second pole proximate the left ventricle.

8 . The method of claim 1 , wherein the implantable medical device comprises an implanted CRT device comprising the one or more processors and coupled to the plurality of electrodes by one or more implanted leads.

9 . The method of claim 1 , wherein the plurality of electrodes comprises a plurality of subcutaneous electrodes, and wherein the medical device system comprises a subcutaneously implanted master device comprising the one or more processors and the plurality of subcutaneous electrodes and a leadless pacemaker slave device configured to deliver the ventricular pacing to the left ventricle.

10 . The method of claim 9 , wherein the plurality of subcutaneous electrodes are implanted in a subcutaneously spaced-apart arrangement.

11 . A medical device system for controlling delivery of cardiac resynchronization therapy (CRT), the system comprising:
therapy delivery circuitry configured to deliver ventricular pacing to a heart of a patient; sensing circuitry configured to sense electrical activity of the heart via a plurality of electrodes; and one or more processors configured to:
control the therapy delivery circuitry to deliver the ventricular pacing according to a sequence of different values of at least one of A-V delay or V-V delay;
during the delivery of ventricular pacing according to the sequence, control the sensing circuitry to acquire one or more electrograms, each of the one or more electrograms from a respective one of a plurality of vectors formed by the plurality of electrodes;
for each of the different values of the at least one of A-V delay or V-V delay, determine at least one of a QRS amplitude or a QRS area based on the one or more electrograms;
identify a target change in QRS amplitude or QRS area between adjacent ones of the values of the at least one of A-V delay or V-V delay of the sequence; and
in response to the identification of the target change, control the therapy delivery circuitry to deliver the ventricular pacing at a value of the at least one of A-V delay or V-V delay determined based on the identification of the target change to provide CRT.

12 . The system of claim 11 , wherein the target change in QRS amplitude or QRS area indicates fusion occurring between right and left ventricles.

13 . The system of claim 11 , wherein the target change in QRS amplitude or QRS area comprises a decrease in QRS amplitude.

14 . The system of claim 11 , wherein the one or more processors are configured to:
control the therapy delivery circuitry to deliver left-ventricular pacing according to a sequence of different values of A-LV delay; and control the therapy delivery circuitry to deliver LV fusion pacing at a value of an A-LV delay determined based on the identification of the target change.

15 . The system of claim 11 , wherein the one or more processors are configured to control the therapy delivery circuitry to deliver the ventricular pacing at the shorter of the adjacent ones of the values of the at least one of A-V delay or V-V delay of the sequence in response to the identification of the target change.

16 . The system of claim 11 , wherein the one or more processors are configured to:
control the sensing circuitry to acquire two electrograms, each of the electrograms acquired from a respective one of two vectors; determine a two-dimensional vectorcardiogram from the two electrograms; and determine the at least one of the QRS amplitude or the QRS area based on the two-dimensional vectorcardiogram.

17 . The system of claim 16 , wherein the electrograms are bipolar electrograms, and each of the two vectors includes a first pole proximate the right ventricle and a second pole proximate the left ventricle.

18 . The system of claim 11 , further comprising:
one or more implantable leads comprising the plurality of electrodes; and an implantable CRT device comprising a housing, and the therapy delivery circuitry, sensing circuitry, and one or more processors within the housing, wherein the implantable CRT device is coupled to the plurality of electrodes by the one or more implanted leads.

19 . The system of cla

Assignees

• Medtronic Inc
• Maastricht Univ Medical Centre

Inventors

• Engels Elien B
• Vernooy Kevin
• Aranda Hernandez Alfonso
• Prinzen Frits W
• Gillberg Jeffrey M

Classifications

• A61N1/37217

  characterised by the communication link, e.g. acoustic or tactile · CPC title

• A61B5/0468

  Human Necessities · mapped topic

• A61N1/36592 Primary

  controlled by the heart rate variability · CPC title

• A61N1/3962

  in combination with another heart therapy · CPC title

• A61N1/3956

  Implantable devices for applying electric shocks to the heart, e.g. for cardioversion · CPC title