Analysis of beat-to-beat late potential variability and the effect of atrial pacing

Late potentials, which are abnormal high-frequency, low-amplitude signals found near the end of the QRS complex, are known to be an indication of susceptibility to ventricular arrhythmias in certain groups of patients. Signal-averaging, the standard method for detecting late potentials, cannot reliably detect signals which are inconsistent from beat-to-beat. Recent attempts to improve the predictive accuracy of signal-averaging by employing atrial pacing to induce cycle-length dependent effects have reported mixed results, possibly due to beat-to-beat variations in the late potential signal. The author reports preliminary results using time-sequenced adaptive filtering to detect late potentials beat-to-beat at the resting heart rate and during atrial pacing.<>