Chronotopocardiography: a new method for presentation of orthogonal electrocardiograms and vectorcardiograms.

A mathematical model was developed to express and visualize signals from 3 orthogonal ECG (vectorcardiographic (VCG) leads as areas of activation on a spherical surface approximating to the walls of the cardiac ventricles, called the image surface. A computer program was compiled for presentation of orthogonal ECGs in the form of a series of instantaneous maps of cardiac activation, as well as chronotopocardiograms displaying the topography and the duration of activation on the image surface on two summary maps.