Flexible Electro‐Optical Arrays for Simultaneous Multi‐Site Colocalized Spatiotemporal Cardiac Mapping and Modulation

Abstract Bioelectronic devices that allow simultaneous accurate monitoring and control of the spatiotemporal patterns of cardiac activity provide an effective means to understand the mechanisms and optimize therapeutic strategies for heart disease. Optogenetics is a promising technology for cardiac research due to its advantages such as cell‐type selectivity and high space‐time resolution, but its efficacy is limited by the insufficient number of modulation channels and lack of simultaneous spatiotemporal mapping capabilities in current implantable cardiac optogenetics tools available for in vivo investigations. Here, soft implantable electro‐optical cardiac devices integrating multilayered highly uniform arrays of transparent microelectrodes and multicolor light‐emitting diodes in thin, flexible platforms are designed for mechanically compliant high‐content high‐precision electrical mapping and single‐/multi‐site optogenetics and electrical stimulation without light‐induced artifacts. Systematic benchtop characterizations, together with ex vivo and in vivo evaluations on healthy and diseased small animal hearts and human cardiac slices demonstrate their functionalities in real‐time spatiotemporal mapping and control of cardiac rhythm and function, with broad applications in basic and ultimately clinical cardiology.