Introducing a hardware-in-the-loop simulation of the cardiovascular system

Advances in direct mechanical ventricular actuation devices have been limited by the inability to test the whole device interaction in-vitro. In this study, we introduce a novel technique to produce a realistic, multimodality cardiovascular simulator to mimic the activity of a beating heart. To achieve the mechanical representation of the heart, each ventricle was defined by a real-time modifiable semicircular pattern of post-buckled spring steel strips with adjustable boundary attachments. The mechanical properties of these strips such as stiffness, length, width and boundary conditions approximated the local and global biomechanical properties of the native heart. This physical heart model interfaced with a mathematical model of the cardiovascular system based on hardware-in-the-loop simulation. In-vitro experiments were carried out in an attempt to investigate into the effect that the DMVA system has on PV loop, cardiac output, and overall hemodynamics under different physiological conditions. By employing this in-vitro setting, assist devices can be physically applied to the circulatory models and assessed before animal or clinical trials are conducted. This will significantly aid device behavioural understanding, development time and cost during device's prototyping.