Engineering Human Myocardium: Integrating the Maturation of hiPSC-Derived Cardiac Myocytes Across Genetic, Structural, Physiological and Multicellular Systems.

The landscape of human cardiac biology was transformed by the discovery that adult somatic cells can be reprogrammed into induced pluripotent stem cells, enabling patient-specific disease modeling, drug testing, and regenerative strategies without the prior ethical or biological constraints. Subsequent advances in directed differentiation made the generation of human iPSC-derived cardiac myocytes reliable and scalable. Despite this progress, a central limitation has remained: these cells are developmentally immature, resembling fetal cardiac myocytes in structure, metabolism, and function. This immaturity restricts their utility for modeling adult-onset disease, predicting drug responses, and achieving clinical translation. Maturation is now understood as a multifactorial symphony, requiring coordinated molecular, structural, and environmental inputs rather than single interventions. As a result, the field is shifting toward integrative approaches that incorporate 3D architecture, multicellular systems, and biomimetic environments to better replicate native cardiac tissue. While fully adult-like myocardium remains an ongoing goal, advances in bioengineering and system-level design are narrowing the gap, with success increasingly defined by the generation of functional cardiac tissue rather than isolated cell maturity.