Method and system for utilizing an atrial contraction timing fiducial in a leadless cardiac pacemaker system

A leadless cardiac pacemaker (LCP) configured to sense cardiac activity and to pace a patient's heart, the LCP disposable within a ventricle of the patient's heart, the LCP comprising:

• a housing;
• a first electrode secured relative to the housing;
• a second electrode secured relative to the housing, the second electrode spaced from the first electrode;
• a controller disposed within the housing and operably coupled to the first electrode and the second electrode such that the controller is capable of receiving electrical cardiac signals from the heart via the first electrode and the second electrode;
• the controller further configured to determine an atrial contraction timing fiducial based at least in part upon a sensed indication of atrial contraction in a first heartbeat and a sensed indication of ventricular contraction in the first heartbeat, an immediately preceding heartbeat and/or an immediately succeeding heartbeat;
• and
• the controller further configured to generate and deliver a ventricle pacing pulse using the atrial contraction timing fiducial.

A method for generating a ventricle pacing pulse using a leadless cardiac pacemaker (LCP) disposed within a patient's left ventricle, the method comprising:

• sensing for a first signal indicating an atrial contraction of a patient's heart;
• sensing for a second different signal related to the atrial contraction of the patient's heart;
• determining an atrial contraction timing fiducial based at least in part on the sensed first signal indicating the atrial contraction of the patient's heart and the sensed second signal related to the atrial contraction of the patient's heart;
• and
• generating and delivering the ventricle pacing pulse using the atrial contraction timing fiducial.