Patent ID: 8843199

Claim:
A method of determining a cardiac response to a pacing pulse, comprising: delivering two or more initialization pacing pulses to the heart using a first electrode combination of a plurality of electrodes that are electrically coupled to a heart; sensing for a cardiac response following each of the two or more initialization pacing pulses using a second electrode combination; for each of the two or more initialization pacing pulses, determining a delay interval between when the initialization pacing pulse was delivered using the first electrode combination until when a corresponding cardiac response was sensed using the second electrode combination; following delivery of the two or more initialization pacing pulses: delivering a pacing pulse to the heart using the first electrode combination; sensing a cardiac response to the pacing pulse using the second electrode combination; and classifying the cardiac response to the pacing pulse as one of a captured response and a non-captured response, the classifying step including: determining if the sensed cardiac response to the pacing pulse has a predetermined characteristic that falls within a classification window, the pre-determined characteristic comprising a peak amplitude that exceeds a pre-determined threshold and wherein the classification window begins after a predetermined time delay following the pacing pulse and extends for a window duration, wherein the predetermined time delay is chosen based at least in part on the determined delay intervals of each of two or more of the initialization pacing pulses.