COMPARISON OF SPECTRAL TEMPORAL MAPPING TO THE TIME-DOMAIN SIGNAL-AVERAGED ELECTROCARDIOGRAM IN NORMAL SUBJECTS AND IN PATIENTS WITH CORONARY-ARTERY DISEASE AND SUSTAINED VENTRICULAR-TACHYCARDIA

Spectral temporal mapping is a new form of analysis for signal-average d electrocardiography which has the goal of improving the sensitivity and specificity of traditional time domain analysis. Our objective in this study was to determine the effectiveness of one form of spectral temporal mapping, in the face of conflicting results that have so far been reported with this approach. We prospectively performed both spec tral temporal mapping and time domain analysis on 50 patients with a h istory of coronary artery disease and inducible sustained monomorphic ventricular tachycardia (Group 1) and on 25 normal subjects with norma l electrocardiograms and no history of heart disease (Group 2). We fou nd that for the 40 Group 1 patients without bundle branch block (Group 1A), the sensitivity of spectral temporal mapping was lower than that for time domain analysis (45% vs 80%, P < 0.005). The results of Spec tral temporal mapping for Group ZA patients were similar to that for a ll of Group 1. The sensitivity of Spectral temporal mapping was 60% (n = 10) for patients with bundle branch block (Group 1B). The specifici ty noted in Group 2 was 88% by each means of analysis; however, no one in Group 2 had an abnormal finding by time domain and spectral tempor al mapping. Attempts to optimize the criteria for an abnormal spectral analysis did not identify criteria that were superior to those curren tly in use. We conclude that spectral temporal mapping using Haberl's method is inferior to time domain analysis in identifying patients wit h sustained ventricular tachycardia, but may be of value in conjunctio n with the traditional approach in identifying normal subjects.