Ventricular far-field sensing to guide atrial leadless pacemaker and beyond

Patent metadata

Field	Value
Publication number	US-12290692-B2
Application number	US-202418440703-A
Country	US
Kind code	B2
Filing date	Feb 13, 2024
Priority date	Jun 1, 2020
Publication date	May 6, 2025
Grant date	May 6, 2025

Abstract

Described herein are methods for use with an implantable system including at least an atrial leadless pacemaker (aLP). Also described herein are specific implementations of an aLP, as well as implantable systems including an aLP. In certain embodiments, the aLP senses a signal from which cardiac activity associated with a ventricular chamber can be detected by the aLP itself based on feature(s) of the sensed signal. The aLP monitors the sensed signal for an intrinsic or paced ventricular activation within a ventricular event monitor window. In response to the aLP detecting an intrinsic or paced ventricular activation itself from the sensed signal within the ventricular event monitor window, the aLP resets an atrial escape interval timer that is used by the aLP to time delivery of an atrial pacing pulse if an intrinsic atrial activation is not detected within an atrial escape interval.

First claim

What is claimed is:

1. An atrial leadless pacemaker (aLP) configured to be implanted in or on an atrial chamber of a patient's heart, the aLP comprising:
two or more electrodes;
a pulse generator electrically coupled or coupleable to at least two of the two or more electrodes;
at least one of a sensor or circuitry configured to sense a signal from which cardiac activity associated with a ventricular chamber of the patient's heart can be detected based on one or more features of the sensed signal;
at least one of a processor or controller configured to
control the pulse generator to selectively generate an atrial pacing pulse for delivery to the atrial chamber via at least two of the two or more electrodes;
specify a ventricular event monitor window;
monitor the sensed signal for a ventricular activation within the ventricular event monitor window; and
reset an atrial escape interval timer, in response to the ventricular activation being detected from the sensed signal within the ventricular event monitor window;
wherein the atrial escape interval timer is used to time delivery of the atrial pacing pulse to the atrial chamber if an intrinsic atrial activation is not detected within an atrial escape interval.

2. The aLP of claim 1 , wherein:
the at least one of the sensor or circuitry comprises sensing circuitry electrically coupled or coupleable to at least two of the two or more electrodes and configured to sense an electrogram (EGM);
the sensed signal, from which cardiac activity associated with the ventricular chamber of the patient's heart can be detected, comprises the EGM; and
the at least one of the processor or controller is configured to monitor the EGM for a far-field R-wave or V-pulse within the ventricular event monitor window to thereby monitor for the ventricular activation, which can be intrinsic or paced.

3. The aLP of claim 1 , wherein:
the at least one of the sensor or circuitry comprises an accelerometer or a pressure sensor configured to sense the signal from which cardiac activity associated with the ventricular chamber of the patient's heart can be detected based on one or more features of the sensed signal; and
the at least one of the processor or controller is configured to monitor the sensed signal for a specific heart sound within the ventricular event monitor window, or for an indication of a mechanical contraction within the ventricular event monitor window, to thereby monitor for the ventricular activation, which can be intrinsic or paced.

4. The aLP of claim 1 , wherein:
to specify the ventricular event monitor window the at least one of the processor or controller is configured to start the ventricular event monitor window at a specified atrial-to-ventricular interval minus a specified non-zero delta, after a paced or intrinsic atrial activation; and
the specified atrial-to-ventricular interval comprises one of a PV-interval, a PR-interval, an AV-interval, or an AR-interval.

5. The aLP of claim 1 , wherein to specify the ventricular event monitor window the at least one of the processor or controller is configured to:
detect an end of a P-wave that corresponds to an intrinsic atrial activation; and
start the ventricular event monitor window at the end of the P-wave or a specified non-zero delta after the end of the P-wave.

6. The aLP of claim 1 , wherein to specify the ventricular event monitor window:
the aLP uses a ventricular event monitor window start timer to determine when the ventricular event monitor window is to start, such that when the ventricular event monitor window start timer times out the ventricular event monitor window is started; and
the at least one of the processor or controller is configured to start the ventricular event monitor window start timer in one of the following manners:
when a P-wave is detected by the aLP;
at an end of the P-wave detected by the aLP;
at a specified delta after the end of the P-wave detected by the aLP;
at a peak of the P-wave detected by the aLP;
at the specified delta after the peak of the P-wave detected by the aLP;
when a said atrial pacing pulse is delivered by the aLP; or
at a further specified delta after the said atrial pacing pulse is delivered by the aLP.

7. The aLP of claim 6 , wherein to specify the ventricular event monitor window:
the aLP uses a ventricular event monitor window timer, which is started when the ventricular event monitor window start timer times out, to determine when the ventricular event monitor window ends.

8. The aLP of claim 1 , wherein the at least one of the processor or controller is configured to determine at least one of a start of or a duration of the ventricular event monitor window based on at least one of an atrial cycle length, a measure of temperature, or a measure of activity, so that the at least one of the start of or the duration of the ventricular event monitor window is rate adaptive.

9. The aLP of claim 1 , further comprising:
one or more receivers configured to receive implant-to-implant (i2i) messages from a ventricular leadless pacemaker (vLP);
wherein the at least one of the processor or controller is configured to time delivery of the atrial pacing pulse to the atrial chamber, based on timing of a premature ventricular contraction (PVC), in response to a said i2i message received from the vLP indicating that the PVC was detected by the vLP.

10. The aLP of claim 1 , further comprising:
one or more receivers configured to receive implant-to-implant (i2i) messages from a ventricular leadless pacemaker (vLP);
wherein the at least one of the processor or controller is configured to disable at least one of the one or more receivers during the ventricular event monitor window to thereby conserve energy.

11. The aLP of claim 1 , wherein the at least one of the processor or controller is configured to:
control the pulse generator, or a further pulse generator of the aLP, to selectively generate conductive communication pulses for use in transmitting an implant-to-implant (i2i) message to a ventricular leadless pacemaker (vLP) to inform the vLP of an intrinsic or paced atrial activation, to thereby enable the vLP to time its delivery of a ventricular pacing pulse based on the intrinsic or paced atrial activation; and
to include, within the i2i message, a status bit that informs the vLP whether the aLP was able to successfully detect the ventricular activation from the sensed signal during one or more previous cardiac cycles.

12. The aLP of claim 1 , wherein the at least one of the processor or controller is configured to:
control the pulse generator, or a further pulse generator of the aLP, to selectively generate conductive communication pulses for use in transmitting an implant-to-implant (i2i) message to a ventricular leadless pacemaker (vLP) to inform the vLP of an intrinsic or paced atrial activation, to thereby enable the vLP to time its delivery of a ventricular pacing pulse based on the intrinsic or paced atrial activation; and
to include, within the i2i message, a status bit that informs the vLP whether the aLP received a valid i2i message from the vLP during one or more previous cardiac cycles, thereby enabling the vLP to determine whether to adjust at least one of an amplitude or a timing of one or more further i2i messages that the vLP transmits to the aLP.

13. The aLP of claim 1 , wherein to monitor the sensed signal for the ventricular activation within the ventricular event monitor window, the at least one of the processor or controller is configured to at least one of:
determine whether a magnitude associated with one or more features of the sensed signal is abov

Assignees

• Pacesetter Inc

Inventors

• Min Xiaoyi
• Yang Weiqun
• Persson Benjamin T
• Badie Nima
• Ryu Kyungmoo
• Mouchawar Gabriel

Classifications

• A61N1/3706

  Pacemaker parameters (stimulation threshold A61N1/371) · CPC title

• A61N1/3688

  configured for switching the pacing mode, e.g. from AAI to DDD · CPC title

• A61N1/3704

  Circuits specially adapted therefor, e.g. for sensitivity control · CPC title

• A61N1/025

  Digital circuitry features of electrotherapy devices, e.g. memory, clocks, processors · CPC title

• A61N1/056

  Transvascular endocardial electrode systems · CPC title