Use of high-pass filtering to detect late potentials in the signal-averaged ECG.

The authors investigate the use of digital filters for analysis of the signal-averaged ECG. They consider the basic types of digital filters and examine respective advantages and disadvantages for ECG analysis. An approach to analyzing the signal-averaged ECG using separate filters for measuring QRS offset and amplitudes is proposed. A study of 19 subjects explores the use of filters to detect low-level activity anywhere in the QRS complex.