Drift compensation in multi-chamber leadless pacemaker system that provides aai+vvi operation

A ventricular leadless pacemaker (vLP) configured to communicate with an atrial LP (aLP) using implant-to-implant (i2i) communication, wherein the vLP is configured to be implanted in or on a ventricular chamber or proximate a left bundle branch (LBB) and to perform pacing of the ventricular chamber, and wherein the aLP is configured to be implanted in or on an atrial chamber and to perform pacing of the atrial chamber, the vLP comprising:

• a receiver configured to receive event messages from the aLP using i2i communication;
• a plurality of electrodes;
• a memory;
• a timing circuitry;
• a pulse generator configured to deliver pacing pulses using at least two of the plurality of electrodes;
• and
• a controller communicatively coupled to the receiver, the pulse generator, the timing circuitry, and the memory;
• the controller configured to:
• during a first period of time, during which the aLP and the vLP transmit event messages to one another, determine and store one or more count values in the memory;
• control the pulse generator to cause the vLP to provide VVI operation during a second period of time during which the aLP and the vLP abstain from transmitting event messages to one another to thereby conserve power, and during which the aLP provides AAI operation;
• during at least one of the first period of time or the second period of time, determine a compensation offset based on at least one of the one or more count values determined and stored during the first period of time, wherein the compensation offset is indicative of a drift between timing circuitry of the aLP and the timing circuitry of the vLP;
• and
• during the second period of time, whenever the vLP is to deliver pacing stimulation to the ventricular chamber to provide the VVI operation and had delivered pacing stimulation to the ventricular chamber during an immediately preceding cardiac cycle, control the pulse generator to time pacing of the ventricular chamber based on the compensation offset, to thereby compensate for the drift between the timing circuitry of the aLP and the timing circuitry of the vLP so that the synchronization between atrial and ventricular pacing is maintained whenever the vLP provides ventricular pacing for two or more consecutive cardiac cycles during the second period of time.

A multi-chamber leadless pacemaker system comprising:

• an atrial leadless pacemaker (aLP);
• and
• a ventricular leadless pacemaker (vLP);
• the aLP and the vLP configured to communicate with one another using implant-to-implant (i2i) communication;
• the aLP configured to be implanted in or on an atrial chamber and to perform pacing of the atrial chamber;
• and
• the vLP configured to be implanted in or on a ventricular chamber or proximate a left bundle branch (LBB) and to perform pacing of the ventricular chamber,
• the vLP comprising:
• a receiver configured to receive event messages from the aLP using i2i communication;
• a plurality of electrodes;
• a memory;
• a timing circuitry;
• a pulse generator configured to deliver pacing pulses using at least two of the plurality of electrodes;
• and
• a controller communicatively coupled to the receiver, the pulse generator, the timing circuitry, and the memory;
• the controller configured to:
• during a first period of time, during which the aLP and the vLP transmit event messages to one another, determine and store one or more count values in the memory;
• control the pulse generator to cause the vLP to provide VVI operation during a second period of time during which the aLP and the vLP abstain from transmitting event messages to one another to thereby conserve power, and during which the aLP provides AAI operation;
• during at least one of the first period of time or the second period of time, determine a compensation offset based on at least one of the one or more count values determined and stored during the first period of time, wherein the compensation offset is indicative of a drift between timing circuitry of the aLP and the timing circuitry of the vLP;
• and
• during the second period of time, whenever the vLP is to deliver pacing stimulation to the ventricular chamber to provide the VVI operation and had delivered pacing stimulation to the ventricular chamber during an immediately preceding cardiac cycle, control the pulse generator to time pacing of the ventricular chamber based on the compensation offset, to thereby compensate for the drift between the timing circuitry of the aLP and the timing circuitry of the vLP so that the synchronization between atrial and ventricular pacing is maintained whenever the vLP provides ventricular pacing for two or more consecutive cardiac cycles during the second period of time.