Abstract: A PPG system includes a processor configured to receive a PPG signal from a PPG sensor, the PPG signal having a plurality of pulses each representing a heartbeat of a patient. The processor is also configured to determine an amplitude variance of the plurality of pulses over a time period, determine a pulse period variance of the PPG signal over the time period, determine a cardiac stability based on a ratio of the amplitude variance and the pulse period variance, and provide an indication of the cardiac stability via a display. The amplitude variance includes an average of squared differences of an amplitude of a peak of each pulse of the plurality of pulses from a mean amplitude of the plurality of pulses over the time period, and the mean amplitude includes an average of respective midpoints of each of the plurality of pulses over the time period.

Abstract: A PPG system includes a processor configured to receive a PPG signal from a PPG sensor, the PPG signal having a plurality of pulses each representing a heartbeat of a patient. The processor is also configured to determine an amplitude variance of the plurality of pulses over a time period, determine a pulse period variance of the PPG signal over the time period, determine a cardiac stability based on a ratio of the amplitude variance and the pulse period variance, and provide an indication of the cardiac stability via a display. The amplitude variance includes an average of squared differences of an amplitude of a peak of each pulse of the plurality of pulses from a mean amplitude of the plurality of pulses over the time period, and the mean amplitude includes an average of respective midpoints of each of the plurality of pulses over the time period.

Abstract: A PPG system for determining cardiac stability of a patient includes a PPG sensor configured to be secured to an anatomical portion of the patient, wherein the PPG sensor is configured to sense a physiological characteristic of the patient. The PPG system includes a monitor operatively connected to the PPG sensor. The monitor receives a PPG signal from the PPG sensor. The monitor includes a cardiac stability analysis module configured to determine an amplitude variance of the PPG signal over a predetermined time period and configured to determine a pulse period variance of the PPG signal over the time period. The cardiac stability analysis module is configured to determine cardiac stability as a function of the amplitude variance and the pulse period variance.