A method for evaluation of electrical propagation in the heart includes receiving a pacing signal applied to a heart of a patient, the pacing signal including a sequence of normal and shorter, abnormal, pacing stimuli. A responsive cardiac signal is received, that is sensed by electrodes at a location in the heart and on the body surface of the patient. A model response is found and annotated from evoked potentials caused by the normal pacing stimuli. A correlation is made between the model response along the different signal sections to find and calculate a normal and decremental time delays between the pacing stimuli and respectively resulting evoked potentials at a tissue location. A time difference is calculated, between the normal time delay and the decremental time delay. An EP map of at least a portion of the heart is presented to a user, with a graphical indication of the time difference presented at the tissue location.