Dynamic number of segments of spectral temporal mapping of the signal-averaged electrocardiogram derived from duration of the QRS complex

The signal-averaged electrocardiogram (ECG) was recorded and analyzed in 30 postinfarction patients with ventricular tachycardia and long late potentials, and in 30 controls with normal signal-averaged ECG to investigate whether the results of spectral temporal mapping of the signal-averaged ECG are disturbed in patients with long late potentials, and to calculate a formula for computing the number of ECF segments to be analyzed in such patients. When a new formula, based on the difference between the total filtered and the standard QRS durations, was used, the identification of patients with ventricular tachycardia and long late potentials was significantly improved