Multi-chamber intracardiac pacing system

A method performed by an implantable medical device system including a first implantable pacemaker having a housing, the implantable medical device system further including a second implantable pacemaker, wherein the method comprises:

• sensing from a cardiac electrical signal received by a first sensing module within the housing of the first implantable pacemaker:
• near field intrinsic cardiac events occurring in a first heart chamber, far field intrinsic events occurring in a second heart chamber different than the first heart chamber, and far field pacing pulses, the far field pacing pulses being pacing pulses delivered in the second heart chamber by the second implantable pacemaker, wherein the housing of the first implantable pacemaker is configured to be implanted within the first heart chamber and the second implantable pacemaker is configured to be implanted within the second heart chamber;
• setting a first pacing escape interval in response to a far field pacing pulse sensed by the first sensing module;
• allowing the first pacing escape interval to continue without restarting the first pacing escape interval in response to a far field intrinsic event sensed by the first sensing module during the first pacing escape interval;
• and
• controlling a pulse generator within the housing of the first implantable pacemaker to deliver a cardiac pacing pulse to the first heart chamber upon expiration of the first pacing escape interval.

A non-transitory, computer-readable storage medium storing a set of instructions that, when executed by a control module within a housing of a first implantable pacemaker of a medical device system including the first implantable pacemaker and a second implantable pacemaker, cause the system to:

• sense from a cardiac electrical signal received by a first sensing module of the first implantable pacemaker near field intrinsic cardiac events occurring in a first heart chamber, far field intrinsic events occurring in a second heart chamber different than the first heart chamber, and far field pacing pulses, the far field pacing pulses being pacing pulses delivered in the second heart chamber by the second implantable pacemaker, wherein the housing of the first implantable pacemaker is configured to be implanted within the first heart chamber and the second implantable pacemaker is configured to be implanted within the second heart chamber;
• setting a first pacing escape interval in response to a far field pacing pulse sensed by the first sensing module;
• allowing the first pacing escape interval to continue without restarting the first pacing escape interval in response to a far field intrinsic event sensed by the sensing module during the first pacing escape interval;
• and
• controlling a pulse generator within the housing of the first implantable pacemaker to deliver a cardiac pacing pulse to the first heart chamber upon expiration of the first pacing escape interval.