Cardiotoxicity remains a major cause of drug attrition and post-market withdrawal, highlighting the need for more physiologically relevant in vitro models capable of reproducing the structural and functional features of mature human cardiac tissue more accurately than state-of-the art 2D and 3D cardiac cell culture systems. This thesis focuses on the development and validation of an engineered platform that combines the use of advanced cardiac cell culture strategies to promote cardiomyocyte maturation and support future applications in drug screening, disease modelling, and predictive cardiac testing.