The present invention relates to a method to provide a mean temporal spatial isochrone (TSI) feature relating to an ECG feature (wave form) of interest, such as the activation of the heart from a single point (QRS), relative to the heart in a torso while using an ECG measurement from an ECG recording device. The method includes: receiving ECG measuring data from the ECG recording device； determining vector cardiogram (VCG) data； receiving a model of the heart, preferably with torso, as an input, preferably based on a request including request parameters； determining mean TSI data values representing the TSI feature relating to an electrophysiological phase representing the ECG feature, the mean TSI providing a location within the heart representing the mean location of the ECG feature at the corresponding time； positioning the mean TSI feature and preferably the vector cardiogram data points in the model of the heart and/or torso at an initial position； and rendering the model of the heart, preferably with torso, with the mean TSI feature, preferably with VCG data related to the TSI, for displaying on a display screen for interpretation of the displayed rendering.
