Technologies and applications of current human cardiac organoids.

Human self-organizing cardioids, a recent breakthrough in cardiac organoid research, are constructed with the specialized cardiac lineage cells derived from human pluripotent stem cells (hPSCs) and have made rapid advancements since 2021. A key advantage of these organoids is their minimal reliance on external interventions, allowing them to more accurately replicate the heart's developmental processes through intrinsic signaling pathways, thereby closely mimicking natural cardiac characteristics. Consequently, they hold significant promise for improving drug safety evaluations, treating both congenital and acquired heart diseases, advancing eugenics practices, developing humanized cardiac disease models, conducting research in regenerative medicine, and understanding how unique environments (such as aerospace) affect human health. This review systematically describes the current various self-organizing cardioid construction techniques, comparing the structural differences caused by diverse signal stimulations, which would be instrumental in optimizing designs for more advanced and mature cardioids. Additionally, we summarize existing applications and address the challenges faced. Despite some uncertainties and challenges in current technologies and applications, this emerging cardiac organoid technology holds promise to provide new possibilities for cardiovascular medicine through continuous refinement.