Method and system for determining pace timing 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;
• a memory disposed within the housing and operably coupled to the controller, the memory configured to store a previously determined atrial contraction timing fiducial;
• a pressure sensor disposed relative to the housing and operably coupled to the controller, the controller configured to receive a pressure signal from the pressure sensor;
• the controller configured to determine an A-V delay relative to the previously determined atrial contraction timing fiducial, the controller configured to adjust the A-V delay based at least in part on the pressure signal;
• and
• the controller configured to generate and deliver a ventricle pacing pulse after the adjusted A-V delay following the previously determined 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 signal representative of cardiac performance;
• determining a timing fiducial for a cardiac cycle;
• adjusting a pacing time relative to the timing fiducial based at least in part on the sensed signal;
• generating and delivering the ventricle pacing pulse at the pacing time in the cardiac cycle;
• and
• following the ventricle pacing pulse, sensing for the signal representative of cardiac performance to determine if the cardiac performance improved using the adjusted pacing time.