Advanced in vitro cardiac models for drug evaluation: integration of organoids, engineered tissues, and...

In vitro cardiac model systems have rapidly advanced as complementary platforms to conventional two-dimensional (2D) cultures and animal models, which, despite their long-standing contributions, exhibit inherent limitations in predicting human cardiac responses. This review highlights recent progress in biomimetic platforms that more faithfully recapitulate the structure and function of the human myocardium, including engineered three-dimensional (3D) tissues, chambered ventricular constructs, self-organizing cardiac organoids, and microphysiological systems. These models are increasingly being applied as Drug Development Tools (DDTs) for safety pharmacology, efficacy testing, and cardiotoxicity assessment, offering improved predictive performance compared to traditional assays. By incorporating key features, such as three-dimensional tissue architecture, multicellular composition, electromechanical coupling, and physiological loading, these platforms enhance the translational relevance of preclinical studies. Recent innovations include maturation-enhanced organoids, vascularized engineered heart tissues, chamber models with physiological pressure-volume dynamics, and chip-based platforms that enable the real-time assessment of contractility and electrophysiology. Importantly, the integration of immune and vascular components, as well as multi-organ connectivity, further extends their applicability to systemic drug evaluations and disease modeling. Collectively, these advances bridge the gap between reductionist in vitro assays and clinical studies and align with emerging regulatory paradigms that emphasize human-relevant and non-animal testing methods. By enabling mechanistic insights into human cardiogenesis, cardiomyocyte maturation, and patient-specific disease modeling, advanced in vitro cardiac platforms hold great promise for precision pharmacology and regenerative medicine. Overall, in vitro cardiac models represent a transformative paradigm for advancing drug discovery, improving safety predictions, and reducing the reliance on animal testing in cardiovascular research.