Methods and systems for optimizing lesion placement to treat cardiac fibrillation in a patient include obtaining a map of one or more measurements indicative of a number and distribution of electrical circuit cores for a duration across a cardiac tissue substrate in response to electrical activity in the cardiac tissue substrate, identifying at least one region for the duration of the cardiac tissue substrate having a number of electrical circuit cores that is higher than a predetermined density threshold, generating a first sample set of lesions, the first sample set of lesions being registered onto the map, calculating and comparing a first total length of the first sample set of lesions to a predetermined length threshold, determining fitness of the first sample set of lesions, wherein fitness criteria is indicative of the level to which the sample set can terminate or at least minimize cardiac fibrillation.