Physiological Calcium Combined with Electrical Pacing accelerates Maturation of Human Engineered Heart Tissue. Physiological Calcium Combined with Electrical Pacing accelerates Maturation of Human Engineered Heart Tissue

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have wide potential application in basic research, drug discovery, and regenerative medicine, but functional maturation remains challenging. Here, we present a simple method whereby maturation of hiPSC-CMs can be accelerated by simultaneous application of physiological Ca 2+ and frequency-ramped electrical pacing in culture. This combination produces realistic force-frequency relationship, physiological twitch kinetics, robust β-adrenergic response, improved Ca 2+ handling, and cardiac troponin I expression within 25 days. This study provides insights into the role of Ca 2+ in hiPSC-CM maturation and offers a scalable platform for translational and clinical research. Overall design: Gene expression profile analysis of 4 experimental groups of engineered heart tissues (EHTs). The four groups are: High Calcium Ramp Pacing (HCRP), High Calcium No Pacing (HCNP), Low Calcium Ramp Pacing (LCRP) and Low Calcium No Pacing (LCNP)