Abstract
Simultaneous interrogation of cardiac electrophysiological and metabolic processes is essential for investigating and treating heart disease. Key challenges remain in creating stretchable multimodal bioelectronic devices capable of organ-scale, label-free probing of electrophysiology and metabolism in vivo. Here, we present stretchable, scalable, large-area transparent microelectrode arrays (MEAs) that integrate up to 144 microelectrodes and interconnects, enabling a centimeter-scale field of view to tackle these challenges. The microelectrodes consist of conductive polymer-coated metal nanowire composites with outstanding optical transparency and electrochemical performance for both electrophysiological sensing and electrical pacing. These large-area arrays exhibit excellent yield, uniformity, biocompatibility, and mechanical deformability like native cardiac tissue. They successfully achieve in vivo spatiotemporal mapping of electrophysiological activity together with colocalized label-free autofluorescence imaging of metabolism across all four beating heart chambers under clinically relevant conditions in small animals, including ischemia, arrhythmia, and device-delivered electrotherapy. The platform offers methodological opportunities to advance basic and clinical cardiology.