A Real-Time Heart-in-the Loop: A Novel Method for Validation of Cardiac Devices

Implantable devices are key tools for cardiac rhythm management. However, the recalls of software-related devices highlight a role for rigorous testing. For example, pacing issues have been reported from incorrect mode or parameter selection, and unintended mode switching triggered by intrinsic rhythm disturbances. These often arise after multiple heart device interactions, underscoring the value of interactive closed-loop testing. For this, we propose a computational virtual heart model that validates device designs and aids clinical understanding of how device parameters impact individual patient heart functions. Biophysical models give insights into cardiac electrophysiology, but computational costs limit real-time applications. Research fellows from the Auckland Bioengineering Institute introduce an advanced in-silico heart activation model for device validation. This model, constructed from hybrid automata (HA), integrates regional electrophysiology and conduction paths, using Simulink^® and Stateflow^® charts. It captures the activity of various cardiac cell types, dynamic responses to diastolic intervals, and regional conduction characteristics. Additionally, an electrogram model facilitates integration with medical devices. An automated framework, including test generation, execution, and evaluation, is also developed, which leverages stochastic optimization algorithms to explore physiological conditions. This achieves high test coverage with clinically relevant responses. The simulated findings align with clinical observations, notably in pacemaker-mediated tachycardia risk assessment. This heart model represents a transformative tool for cardiac device development and verification. It provides a cost-effective and ethically responsible method to optimize device performance and predict clinical outcomes prior to in-vivo testing. Future work will expand the model's application to emerging cardiac therapies and support regulatory decision-making processes for device approval.