System and method for predicting cardiac arrhythmia utilizing frequency information derived from multiple segments of the late QRS and the ST portion

摘要

Several hundred digitized ECG waveforms are averaged together (discarding abnormal waveforms) to form an array of digitized values. Then multiple overlapping subsegments are extracted from this array, processed by a window function in a way that produces a D.C. free result, and transformed into the frequency domain. The logarithm of the square of the amplitude (down to a minimum noise threshold level) of these frequency domain values are then plotted in a three-dimensional plot that graphically illustrates whether or not the patient from whom the waveforms were taken is likely to be at risk of cardiac arrhythmia in the near future. Cross correlation of these functions against one far removed from the QRS complex enables a factor of normality to be computed.