Optical imaging plays a crucial role in basic cardiovascular research. In this talk, I will discuss the latest developments in the field of cardiac optical mapping, and demonstrate that it is possible to image action potential and calcium wave phenomena on the surface of the beating heart in real-time. Using a mix of optical and numerical computer vision techniques, including, for instance, voltage-sensitive fluorescent dyes, ratiometric imaging and numerical motion tracking, it is possible to simultaneously measure mechanical tissue deformation, as well as electrophysiological wave phenomena at very high spatial and temporal resolutions. I will discuss some of the experimental requirements, e.g. illumination, optics, preparation of the tissue, and will review the state-of-the-art in numerical techniques and hardware requirements for performing the measurements in real-time at imaging speeds of 500fps. Further, I will discuss how the superposition of motion and fluorescence-related phenomena poses a tricky problem, which needs to be addressed when imaging and post-processing the data. In this context, I will discuss the origin of motion artifacts, the importance of a co-moving measurement, the effect of inhomogeneous illumination, and how cross-talk between mechanics and electrophysiology may negatively affect the measurement [1,2]. Most importantly, I will demonstrate that deep learning is very successfull in solving some of these issues, as it can learn the complex relationship between motion, illumination and fluorescence-encoded electrophysiology, and can use this information to correctly disentangle the involved physical phenomena leading to reliable and accurate measurements. Using this powerful technique, it becomes possible to study electromechanical phenomena in great detail. For instance, we studied and were able to resolve rotor dynamics in fibrillating contracting hearts and found a strong correlation between tissue mechanics and electrophysiology [3]. Lastly, I will explain some of the limitations of cardiac optical mapping and potential future directions.