Human-heart-model for hardware-in-the-loop testing of pacemakers

To guarantee the safety of medical devices, including embedded systems, it is essential to consider both electronic components and the natural environment during validation and verification. In contrast to prior research, we present a hardware-in-the-loop environment that connects a real medical system to a biological model in real time for validation, including the modeling of the mechanical component of the heart valves in addition to the modeling of the electrical conduction and electrical stimulation of the heart chambers. Our model accounts for the dynamic adaptation of the temporal processes in the heart chambers to the pacing frequency of the individual chambers as a function of the action potential. This study investigates two additional risk factors affecting the heart under different conditions: pacemaker syndrome and electrical stimulation during the vulnerable phase. Both can be life-threatening to the patient if left untreated. In implementing our concept on a physical pacemaker connected to our software-based model of the heart, we discovered that the test pacemaker was unable to generate the required heart rate in three of the scenarios we tested. Additionally, our tests revealed occurrences of pacemaker syndrome and stimulation in the vulnerable phase.