Atrial contraction detection by a ventricular leadless pacing device for atrio-synchronous ventricular pacing

Patent metadata

Field	Value
Publication number	US-9399140-B2
Application number	US-201414579105-A
Country	US
Kind code	B2
Filing date	Dec 22, 2014
Priority date	Jul 25, 2014
Publication date	Jul 26, 2016
Grant date	Jul 26, 2016

Abstract

A leadless pacing device (LPD) includes a motion sensor configured to generate a motion signal as a function of heart movement. The LPD is configured to analyze the motion signal within an atrial contraction detection window that begins an atrial contraction detection delay period after activation of the ventricle, and detect a contraction of an atrium of the heart based on the analysis of the motion signal within the atrial contraction detection window. If the LPD does not detect a ventricular depolarization subsequent to the atrial contraction, e.g., with an atrio-ventricular (AV) interval beginning when the atrial contraction was detected, the LPD delivers a ventricular pacing pulse.

First claim

What is claimed is:

1. A leadless pacing device configured to deliver atrio-synchronous ventricular pacing, the leadless pacing device comprising:
a plurality of electrodes;
a motion sensor configured to generate a motion signal as a function of movement of a heart of a patient;
a stimulation module coupled to the plurality of electrodes, wherein the stimulation module is configured to generate pacing pulses and deliver the pacing pulses to a ventricle of the heart via the plurality of electrodes;
an electrical sensing module coupled to the plurality of electrodes, wherein the electrical sensing module is configured to detect depolarizations of the ventricle within a cardiac electrogram sensed via the plurality of electrodes;
a mechanical sensing module coupled to the motion sensor and configured to:
receive the motion signal from the motion sensor;
identify an activation of the ventricle;
upon identification of the activation of the ventricle, initiate an atrial contraction detection delay period;
analyze the motion signal within an atrial contraction detection window that begins upon completion of the atrial contraction detection delay period; and
detect a contraction of an atrium of the heart based on the analysis of the motion signal within the atrial contraction detection window;

a processing module configured to control the stimulation module to generate a pacing pulse and deliver the pacing pulse to the ventricle via the plurality of electrodes in response to the detection of the contraction of the atrium by the mechanical sensing module; and
a housing configured to be implanted within the ventricle, wherein the housing encloses the motion sensor, the stimulation module, the electrical sensing module, the mechanical sensing module, and the processing module;
wherein the processing module is configured to:
determine that the electrical sensing module did not detect a depolarization of the ventricle within an atrioventricular (AV) interval beginning when the mechanical sensing module detected the contraction of the atrium; and
control the stimulation module to generate the pacing pulse and deliver the pacing pulse to the ventricle via the plurality of electrodes in response to the determination; and,
wherein the mechanical sensing module is configured to detect a contraction of the ventricle based on the motion signal after delivery of the pacing pulse to the ventricle, and the processing module is configured to:
determine whether the delivery of the pacing pulse to the ventricle was effective based on the detection of the contraction of the ventricle; and
adjust the AV interval based on the determination of whether the delivery of the pacing pulse to the ventricle was effective.

2. The leadless pacing device of claim 1 , wherein the processing module is configured to:
determine that an interval from the delivery of the pacing pulse to the detection of the contraction of the ventricle is less than a threshold; and
decrease the AV interval in response to the determination that the interval from the delivery of the pacing pulse to the detection of the contraction of the ventricle is less than the threshold.

3. The leadless pacing device of claim 1 ,
wherein the mechanical sensing module is configured to:
detect a peak of the ventricular contraction based on the motion signal; and
determine an amplitude of the motion signal at the peak, and

wherein the processing module is configured to:
determine that the amplitude is greater than the threshold; and
increase the AV interval in response to the determination that the amplitude is greater than the threshold.

4. A leadless pacing device configured to deliver atrio-synchronous ventricular pacing, the leadless pacing device comprising:
a plurality of electrodes;
a motion sensor configured to generate a motion signal as a function of movement of a heart of a patient;
a stimulation module coupled to the plurality of electrodes, wherein the stimulation module is configured to generate pacing pulses and deliver the pacing pulses to a ventricle of the heart via the plurality of electrodes;
an electrical sensing module coupled to the plurality of electrodes, wherein the electrical sensing module is configured to detect depolarizations of the ventricle within a cardiac electrogram sensed via the plurality of electrodes;
a mechanical sensing module coupled to the motion sensor and configured to:
receive the motion signal from the motion sensor;
identify an activation of the ventricle;
upon identification of the activation of the ventricle, initiate an atrial contraction detection delay period;
analyze the motion signal within an atrial contraction detection window that begins upon completion of the atrial contraction detection delay period; and
detect a contraction of an atrium of the heart based on the analysis of the motion signal within the atrial contraction detection window;

a processing module configured to control the stimulation module to generate a pacing pulse and deliver the pacing pulse to the ventricle via the plurality of electrodes in response to the detection of the contraction of the atrium by the mechanical sensing module; and
a housing configured to be implanted within the ventricle, wherein the housing encloses the motion sensor, the stimulation module, the electrical sensing module, the mechanical sensing module, and the processing module;
wherein the processing module is configured to:
determine that the electrical sensing module did not detect a depolarization of the ventricle within an atrioventricular (AV) interval beginning when the mechanical sensing module detected the contraction of the atrium; and
control the stimulation module to generate the pacing pulse and deliver the pacing pulse to the ventricle via the plurality of electrodes in response to the determination; and,
wherein the AV interval comprises a mechanical AV interval,
wherein the electrical sensing module is configured to detect depolarizations of the atrium within the cardiac electrogram sensed via the plurality of electrodes,
wherein, in response to the electrical sensing module detecting a depolarization of the atrium, the processing module is configured to:
determine that the electrical sensing module did not detect a depolarization of the ventricle within an electrical AV interval beginning when the electrical sensing module detected the depolarization of the atrium; and
control the stimulation module to generate a pacing pulse and deliver the pacing pulse to the ventricle via the plurality of electrodes in response to the determination that the electrical sensing module did not detect a depolarization of the ventricle,

wherein the processing module is further configured to determine that the electrical sensing module did not detect a depolarization of the atrium during a predetermined number of one or more cardiac cycles and, in response to the determination:
control the mechanical sensing module to detect a contraction of the atrium based on the motion signal;
determine that the electrical sensing module did not detect a depolarization of the ventricle within the mechanical AV interval beginning when the mechanical sensing module detected the contraction of the atrium; and
control the stimulation module to generate a pacing pulse and deliver the pacing pulse to the ventricle via the plurality of electrodes in response to the determination that the mechanical sensing module did not detect a depolarization of the ventricle, and

wherein the electrical AV interval is greater than the mechanical AV interval.

5. A leadless pacing device configured to deliver atrio-synchronous ventricular pacing, the leadless pacing device comprising:
a plurality of electrodes;
a motion sensor configured to generate a motion si

Assignees

• Medtronic Inc

Inventors

• Cho Yong K
• Sambelashvili Aleksandre T
• Sheldon Todd J

Classifications

• A61N1/36578 Primary

  controlled by mechanical motion of the heart wall, e.g. measured by an accelerometer or microphone · CPC title

• A61N1/3756

  Casings with electrodes thereon, e.g. leadless stimulators · CPC title

• A61N1/3682

  with a variable atrioventricular delay · CPC title

• A61N1/37288

  Communication to several implantable medical devices within one patient · CPC title

• A61N1/36585

  controlled by two or more physical parameters · CPC title