Introduction and Aims: Cardiac optical mapping is becoming increasingly popular for quantifying cardiac spatiotemporal dynamics, with recent advances enabling high-quality recordings from high-resolution CMOS cameras at relatively low prices ($500). Analyzing the large data sets to extract quantitative information is now a bottleneck.
Methods: We developed VizCOM, a feature-rich Python-based tool for visualizing and analyzing cardiac optical mapping data. VizCOM was developed in a close collaboration between experimentalists and software developers.
Results: VizCOM can process very long (minutes) voltage or voltage-calcium recordings. A mask can be easily drawn to isolate a region of interest (A-B), and the signal from a given pixel can be displayed by moving the mouse over the image (C). Several filtering methods have been implemented, including stacking and baseline drift removal methods (C). Activation maps (by colors and/or isochrones) for wave fronts (D) and/or backs can be displayed. Plots of action potential duration (APD) vs. diastolic interval for all pixels in the tissue (E) and of APD dispersion across the whole tissue are available for each beat, as well as ∆APD plots for alternans (F). In addition, APD can be calculated for a line drawn across the tissue to analyze alternans (G). All quantified values can be saved, including histograms of APD spatial distributions, APD restitutions, and movies of the activation sequences. VizCOM also can handle data recordings from a variety of cameras.
Conclusion: VizCOM is a comprehensive program that provides high-level support for the visualization and analysis of cardiac optical mapping signals.