TEMPORAL AND SPATIAL-ANALYSIS OF POTENTIAL MAPS VIA MULTIRESOLUTION DECOMPOSITIONS

Cardiac potentials recorded on the epicardium or the body surface by a n array of electrodes are usually analyzed either as spatial distribut ions or temporal waveforms. Thus, the analysis often involves temporal descriptors (eg, max dV/dt) or spatial descriptors (eg, location of l ocal extrema) only, The best known transform technique that has been a pplied to these data that combines both spatial and temporal character istics is the karhunen-Loeve transform, a global transform applied to temporal and/or spatial bases obtained by statistical analysis of a da tabase. As an alternative, multiresolution decompositions and related wavelet-type transforms have recently seen great development in signal processing and related fields. They offer flexibility, employing tran sformations onto local (rather than global) and fixed (rather than dat a-dependent) databases, and allow transformation of distributions, wav eforms, or both, as desired. The utility of this method as applied to temporal and spatial segmentation and analysis of map data from both e picardial plaques and body surface potentials recorded during percutan eous trans luminal coronary angioplasty is illustrated.