Methodological development of a pneumatic artificial muscle-driven left ventricular simulator using interpretive structural modeling

Mock circulation systems can replicate a wide range of cardiac operating scenarios, such as cardiovascular diseases, particularly muscular dysfunctions. These systems are operated by sophisticated control algorithms which require complex driver and data acquisition systems, whereas animal models raise ethical concerns. Therefore, there is a need for novel testbeds to overcome the challenges in the existing systems. The aim of this study is to develop a less complex and realistic left ventricular (LV) simulator. The Interpretive Structural Modeling (ISM) approach was utilized to evaluate different left ventricular actuation methods and materials. ISM revealed that the most suitable method to actuate the LV is using the pneumatic artificial muscles and latex rubber. The performance of the new LV simulator was evaluated for healthy and diseased conditions at 50, 60, 70 and 80 bpm heart rates. The experiments revealed that the beating LV simulator can generate average flow rates of up to 2.25 L/min. The actual human LV-like wall motion was also verified by the twisting angle on the apex of the beating LV simulator with 21 degrees of rotation and 11 mm of apex shortening. The prototyped beating LV simulator is a promising preliminary platform and may reach actual human LV’s hemodynamic and cardio-mechanical performance with further improvements.