# US 12,214,208 B2 · Atrial tracking in an intracardiac ventricular pacemaker > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,214,208 B2 - Document ID: US12214208B2 - Status: Granted - Kind: B2 - Application number: 17/722,756 - Filed: 2022-04-18 - Published: 2022-10-13 - Granted: 2025-02-04 - Earliest claimed: 2016-09-29 - Assignees: Medtronic, Inc. - Applicants: Medtronic, Inc. - Inventors: Vincent E. Splett; Todd J. Sheldon; Yong K. Cho; Wade M. Demmer; Mark K. Erickson - Web page: https://patentgrep.com/patent/US12214208B2 ## CPC - A61N 1/36578: {controlled by mechanical motion of the heart wall, e.g. measured by an accelerometer or microphone} - A61N 1/36542: {controlled by body motion, e.g. acceleration} - A61N 1/36585: {controlled by two or more physical parameters} - A61N 1/3682: {with a variable atrioventricular delay} - A61N 1/3684: {for stimulating the heart at multiple sites of the ventricle or the atrium} - A61N 1/3756: {Casings with electrodes thereon, e.g. leadless stimulators} - A61N 1/056: {Transvascular endocardial electrode systems} - A61N 1/37205: {Microstimulators, e.g. implantable through a cannula} - A61N 1/37512: {Pacemakers} - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) ## Abstract An intracardiac ventricular pacemaker is configured to detect a ventricular diastolic event from a motion signal received by a pacemaker control circuit from a motion sensor. The control circuit starts an atrial refractory period having an expiration time set based on a time of the detection of the ventricular diastolic event. The control circuit detects an atrial systolic event from the motion signal after expiration of the atrial refractory period and controls a pulse generator of the pacemaker to deliver a pacing pulse to a ventricle of a patient's heart at a first atrioventricular pacing time interval after the atrial systolic event detection. ## Claims ### Claim 1 A pacemaker, comprising: a motion sensor configured to sense a motion signal; and a control circuit coupled to the motion sensor and a pulse generator and configured to: determine from the motion signal a timing of a ventricular diastolic event; start a time period having an expiration time set based on the timing of the ventricular diastolic event; and detect an atrial systolic event from the motion signal after the expiration time of the time period; and the pulse generator configured to generate a first pacing pulse in response to the control circuit detecting the atrial systolic event. ### Claim 2 (depends on 1) The pacemaker of claim 1, wherein the control circuit is further configured to determine the timing of the ventricular diastolic event from the motion signal by determining a timing of a ventricular passive filling event. ### Claim 3 (depends on 1) The pacemaker of claim 1, wherein: the pulse generator is further configured to generate a preceding pacing pulse before the first pacing pulse; and the control circuit is further configured to start the time period in response to the pulse generator generating the preceding pacing pulse. ### Claim 4 (depends on 1) The pacemaker of claim 1, wherein: the pulse generator is further configured to generate a plurality of pacing pulses for a plurality of cardiac cycles; the motion sensor is further configured to sense the motion signal over the plurality of cardiac cycles; and the control circuit is further configured to determine the timing of the ventricular diastolic event using the motion signal sensed over the plurality of cardiac cycles. ### Claim 5 (depends on 1) The pacemaker of claim 1, further comprising a sensing circuit configured to: sense a cardiac electrical signal; sense a ventricular electrical event signal from the cardiac electrical signal; wherein the control circuit is further configured to start the time period in response to the sensing circuit sensing the ventricular electrical event signal. ### Claim 6 (depends on 1) The pacemaker of claim 1, wherein the control circuit is further configured to: receive the motion signal over a plurality of ventricular cycles; average the motion signal over the plurality of ventricular cycles; and determine the timing of the ventricular diastolic event from the averaged motion signal. ### Claim 7 (depends on 1) The pacemaker of claim 1, wherein: the control circuit is further configured to start an atrioventricular pacing interval in response to detecting the atrial systolic event from the motion signal; and the pulse generator is further configured to generate the first pacing pulse in response to an expiration of the atrioventricular pacing interval. ### Claim 8 (depends on 1) The pacemaker of claim 1, wherein the control circuit is further configured to determine the timing of the ventricular diastolic event by comparing the motion signal to a threshold amplitude. ### Claim 9 (depends on 1) The pacemaker of claim 1, wherein the control circuit is further configured to set the expiration time of the time period based on the timing of the ventricular diastolic event by setting the expiration time to be prior to the timing of the ventricular diastolic event. ### Claim 10 (depends on 1) The pacemaker of claim 1, further comprising: a housing enclosing the pulse generator, the motion sensor and the control circuit; and a cathode electrode and anode electrode carried by the housing and coupled to the pulse generator for delivering the first pacing pulse generated by the pulse generator. ### Claim 11 A non-transitory computer-readable medium storing a set of instructions which when executed by a control circuit of a pacemaker having a motion sensor, cause the pacemaker to: sense a motion signal; determine from the motion signal a timing of a ventricular diastolic event; start a time period having an expiration time set based on the timing of the ventricular diastolic event; detect an atrial systolic event from the motion signal after the expiration time of the time period; and generate a first pacing pulse in response to detecting the atrial systolic event detection. ### Claim 12 (depends on 11) The non-transitory computer-readable medium of claim 11 further storing instructions that cause the pacemaker to determine the timing of the ventricular diastolic event from the motion signal by determining a timing of a ventricular passive filling event. ### Claim 13 (depends on 11) The non-transitory computer-readable medium of claim 11 further storing instructions that cause the pacemaker to: generate a preceding pacing pulse before the first pacing pulse; and start the time period in response to the pulse generator generating the preceding pacing pulse. ### Claim 14 (depends on 11) The non-transitory computer-readable medium of claim 11 further storing instructions that cause the pacemaker to: generate a plurality of pacing pulses for a plurality of cardiac cycles; sense the motion signal over the plurality of cardiac cycles; and determine the timing of the ventricular diastolic event using the motion signal sensed over the plurality of cardiac cycles. ### Claim 15 (depends on 11) The non-transitory computer-readable medium of claim 11 further storing instructions that cause the pacemaker to: sense a cardiac electrical signal; sense a ventricular electrical event signal from the cardiac electrical signal; and start the time period in response to the sensing circuit sensing the ventricular electrical event signal. ### Claim 16 (depends on 11) The non-transitory computer-readable medium of claim 11 further storing instructions that cause the pacemaker to: sense the motion signal over a plurality of ventricular cycles; average the motion signal over the plurality of ventricular cycles; and determine the timing of the ventricular diastolic event from the averaged motion signal. ### Claim 17 (depends on 11) The non-transitory computer-readable medium of claim 11 further storing instructions that cause the pacemaker to: start an atrioventricular pacing interval in response to detecting the atrial systolic event from the motion signal; and generate the first pacing pulse in response to an expiration of the atrioventricular pacing interval. ### Claim 18 (depends on 11) The non-transitory computer-readable medium of claim 11 further storing instructions that cause the pacemaker to determine the timing of the ventricular diastolic event by comparing the motion signal to a threshold amplitude. ### Claim 19 (depends on 11) The non-transitory computer-readable medium of claim 11 further storing instructions that cause the pacemaker to set the expiration time of the time period based on the timing of the ventricular diastolic event by setting the expiration time to be prior to the timing of the ventricular diastolic event. ### Claim 20 A method comprising: sensing a motion signal; determining from the motion signal a timing of a ventricular diastolic event; starting a time period having an expiration time set based on the timing of the ventricular diastolic event; detecting an atrial systolic event from the motion signal after the expiration time of the time period; and generating a first pacing pulse in response to detecting the atrial systolic event detection.