A system for analyzing intracardial electrogram data, the system comprising: - a computing device comprising at least one computer readable medium , the computing device storing instructions executable by at least one processor - a data output unit comprising a data output screen for displaying results of electrophysiological data analysis, wherein the computing device is configured to receive electrophysiological data obtained from a mapping catheter assembly that comprises an electrode assembly with a plurality of n electrodes , each electrode configured for measuring electrophysiological data in the form of electrogram signals, wherein the computing device is configured to: (a) assign predetermined positions of electrodes on the electrode assembly to their respective corresponding electrogram signals; (b) provide or generate a two-dimensional spatial map of the electrode positions ; (c) for discrete times over which the electrogram signals are being processed, process the electrogram signals to generate a plurality of three-dimensional electrogram surfaces corresponding at least partially to the 2D map, one surface being generated for each discrete time, and (d) process the plurality of three-dimensional electrogram surfaces through time to generate, using optical flow analysis, a velocity vector map corresponding at least partially to the 2D map, the data output unit being configured to display the velocity vector map on the data output screen of the data output unit. - a computing device comprising at least one computer readable medium , the computing device storing instructions executable by at least one processor - a data output unit comprising a data output screen for displaying results of electrophysiological data analysis, wherein the computing device is configured to receive electrophysiological data obtained from a mapping catheter assembly that comprises an electrode assembly with a plurality of n electrodes , each electrode configured for measuring electrophysiological data in the form of electrogram signals, wherein the computing device is configured to: (a) assign predetermined positions of electrodes on the electrode assembly to their respective corresponding electrogram signals; (b) provide or generate a two-dimensional spatial map of the electrode positions ; (c) for discrete times over which the electrogram signals are being processed, process the electrogram signals to generate a plurality of three-dimensional electrogram surfaces corresponding at least partially to the 2D map, one surface being generated for each discrete time, and (d) process the plurality of three-dimensional electrogram surfaces through time to generate, using optical flow analysis, a velocity vector map corresponding at least partially to the 2D map, the data output unit being configured to display the velocity vector map on the data output screen of the data output unit. (a) assign predetermined positions of electrodes on the electrode assembly to their respective corresponding electrogram signals; (b) provide or generate a two-dimensional spatial map of the electrode positions ; (c) for discrete times over which the electrogram signals are being processed, process the electrogram signals to generate a plurality of three-dimensional electrogram surfaces corresponding at least partially to the 2D map, one surface being generated for each discrete time, and (d) process the plurality of three-dimensional electrogram surfaces through time to generate, using optical flow analysis, a velocity vector map corresponding at least partially to the 2D map, the data output unit being configured to display the velocity vector map on the data output screen of the data output unit. <EOS>