This conference poster presents the development of an advanced 3D iPSC-derived cardiac model designed to improve the assessment of drug-induced cardiotoxicity. Using the SmartHeart® hydrogel-based 4D platform, human iPSC-derived cardiomyocytes (YBLiCardio) were co-cultured with cardiac fibroblasts to form functional ring-shaped cardiac tissues. The model demonstrated synchronized contractility, calcium signaling activity, and expression of key cardiac markers, indicating functional maturation. This approach offers a more physiologically relevant system compared to traditional 2D models for evaluating cardiac safety during early drug development.