Heart-on-a-Chip: Theory, Evidence, and Personalised Medicine

Cardiovascular research traditionally relies on animal models or isolated cell cultures, each having limitations in accurately mimicking human heart function and disease. Organ-on-chip technology is the future of translational research studying clinical pathophysiology, drug testing, and personalised medicine. Organs are precisely replicated via their microenvironment and function. This review introduces clinicians to the heart-on-a-chip (HOC) technology, an advanced approach that replicates critical features of the human heart through engineered, microfluidic platforms. HOC models provide clinicians with a more accurate, reliable alternative for studying heart disease and evaluating drug safety, thus reducing dependence on animal testing. The review begins with an explanation of cardiac anatomy and electrophysiology, emphasising their complexities and challenges in traditional modelling. It then describes current advancements in scaffold-based HOC methods, particularly, using decellularised extracellular matrix and innovative techniques such as three-dimensional bioprinting to realistically reconstruct heart tissue architecture and cellular orientation. Special attention is given to electrophysiological considerations, including artificial stimulation methods designed to replicate the heart's intrinsic electrical conduction pathways. The article also discusses significant improvements in real-time and non-invasive monitoring of cardiomyocyte function. By understanding these developments, clinicians will gain insights into how HOC technology can transform cardiovascular research, enhance patient safety by reducing drug-induced cardiotoxicity risks, and pave the way for personalised medicine through patient-specific cardiac models using induced pluripotent stem cells. Ultimately, this review equips clinician readers with the knowledge to understand the milieu of HOC technology, research, diagnostics, and personalised patient care.