Various embodiments are described herein for detecting a rotor at a location of a heart that experiences cardiac fibrillation. This generally involves obtaining a plurality of bipolar EGMs for a recording duration using a circular bipolar electrode array positioned at the location of the heart； detecting a dominant periodicity Cycle Length (CL) and identifying periodic activations for each bipolar EGM associated with the dominant periodicity CL； tracking the identified periodic activations across each bipolar EGM to define rotational activations and determining when a path taken by the tracked rotational activations corresponds to a rotational activation pattern of a rotor； and detecting the rotor when a number and completeness of the tracked rotational activations meet predefined rotor criteria.
