A cardiac simulation method includes storing, in a memory, a measured electrophysiological (EP) map of at least part of wall tissue of a heart of a patient. Based on the stored EP map, simulated electrical activity in response to computer-simulated pacing, which simulates actual electrical activity that would occur across the wall tissue of the heart of the patient in response to actual pacing, is calculated in a processor. Based on the simulated electrical activity calculated in the processor, one or more candidate locations on the wall tissue of the heart at which arrhythmia is suspected of originating are identified and indicated to a user.
