Inverse localization of the latest-activated areas in the ventricles from body surface potential maps

In this simulation study an identification of the latest depolarized site of the ventricles from integral body surface potential maps (BSPMs) using an inverse solution in terms of one or two dipoles was tested on models of a normal heart. The input data for the inverse solution were integral BSPMs computed from the interval of the last 5 or 10 ms of depolarization. It was assumed that such integral BSPMs represents a small activated area so that they can be approximated by a single dipole. The BSPMs were produced by two types of normal heart-torso models. The very last activated points on the surfaces of the ventricular models were known. If there was a single latest activated area, the localization error was between 0.5 and 3.5 cm. If there were two distinct latest activated areas, the localization error was between 1. 7 and 2. 9 cm. The proposed method could be used for the preliminary noninvasive assessment of the latest-activated ventricular areas, which are of great interest for cardiac resynchronization therapy.