Light and the Heart

Optogenetics is an emerging technology for optical interrogation and control of excitable tissues by merging genetic and optical means. The traditional description of optogenetics involves the use of light and optics to modulate cell, tissue, organ, and animal function through activation of light-sensitive ion channels and pumps. This chapter describes the basic principles of optogenetics, the available and evolving optogenetic toolbox, and the unique potential of this technology for basic and translational cardiac electrophysiology. It focuses on optogenetic sensors and describes the utilization of genetically encoded voltage and calcium indicators for optical monitoring of the electrophysiological and calcium-handling properties of cardiac tissues. The chapter discusses the ability to control cardiac excitability using optogenetic actuators, with a specific emphasis on the potential of this technology for treating cardiac arrhythmias. The advantages and potential applications of combining these two technologies for simultaneous optical sensing and actuation are discussed.