2-D spatiotemporal imaging of T-wave alternans in precordial ECG leads by means of Poincare sections

T-wave alternans (TWA), i.e., characteristic variations of the T-wave shape in ECGs are considered as important indicator of myocardial ischemia posing risk of sudden death. The aim of the study is proposition of a new visualization scheme of TWA detected in standard V1-V6 precordial leads. TWA levels are detected by means of Poincare sections then, 2-D spatiotemporal maps are obtained by means of biharmonic spline interpolation method. TWA mappings are tested on 30 ECGs recorded from postinfarction patients. TWA maps can be used for simultaneous spatio-temporal location of alternans in precordial leads – feature not offered in other TWA detection methods.