Effective strategies in cardiac tissue engineering require matrices that recapitulate the mechanical,topographic and electrical cues present in the native extracellular matrix.In this review,we discuss recent efforts in materials science and nanotechnology to achieve functional three-dimensional (3D) scaffolds that modulate and monitor cardiac tissue function.We consider key design considerations,including choice of biopolymer matrix,cell sources,and deliverymethods for eventual therapies.We then discuss how solid-state nanomaterials may be integrated within these systems to provide unique electrical and nanotopographic cues that improve electromechanical synchrony.We describe how these approaches may be extended to complex,spatially heterogeneous constructs using 3D bioprinting techniques.Finally,we describe how scaffold materials may be augmented with bioelectronic components to achieve hybrid myocardium that monitors or controls elsctrophysiological activity.Collectively,these approaches provide a framework for achieving cardiac tissues with tunable,rationally-designed functionalities.We discuss future prospects and remaining challenges for clinical translation.