There is a need for accurate measurements of mechanical strain and motion of the heart both in vitro and in vivo. We have developed a new structured-light imaging system capable of epicardial shape measurement at 333 fps at a resolution of 768 × 768 pixels. Here we present proof-of-concept data from our system applied to a beating rabbit heart in vitro to measure epicardial mechanics. This method will allow high resolution mapping of epicardial strain and virtual immobilization of the heart for removal of motion artifacts from epicardial recordings with fluorescence dyes. This will allow mapping of transmembrane potential and calcium transients in a beating heart, including in vivo.