ENDOCARDIAL FRAGMENTED ELECTROGRAM AND PREDICTION OF VENTRICULAR-TACHYCARDIA BY BODY-SURFACE SIGNAL-AVERAGED ELECTROCARDIOGRAPHIC MAPPING

Signal-averaged (SA) electrocardiography and SA electrocardiographic m apping were performed in 50 patients with old myocardial infarction, 1 9 of whom had left ventricular aneurysm and 11 of whom had clinical su stained ventricular tachycardia. The SA electrocardiogram and SA elect rocardiographic mapping data were then compared with those obtained by endocardial catheter mapping in patients with or without fragmented e lectrograms, sustained ventricular tachycardia, and ventricular aneury sm. Compared to SA electrocardiography, the SA map correlates with sus tained VT with improved sensitivity but decreased specificity. However , SA electrocardiographic mapping had the advantage of displaying the extent of the body surface area that was positive for late potentials. In addition, the site of the longest endocardial fragmented electrogr am could be predicted by SA electrocardiographic mapping suggesting th at this technique deserves wider clinical application.