Systems and methods for determining prevalence of a cardiac phenomenon based on electrophysiological (EP) data from a tissue of a body are provided. The EP data is measured by at least one sensor disposed on at least one medical device that is positionable near the tissue of the body. A system includes an electronic control unit communicatively coupled to a display device and configured to, for each of the plurality of locations, detect, at each of a plurality of discrete times occurring during a predetermined time period, whether a cardiac phenomenon occurs at the location based on the EP data, determine a prevalence of the cardiac phenomenon based on the detecting, and display information indicative of the determined prevalence of the cardiac phenomenon on the display device.
