Design of a Motor-Torsion Driven 3D-Printed Left Ventricular Mock Circulation System and Hemocompatibility Assessment

In vitro testing of ventricular assist devices, constructing a mock circulation system that reproduces physiological cardiac function, is critical. However, current ventricular simulators often lack biomimetic fidelity and may introduce hemolysis and coagulation risks during prolonged operation, affecting hemocompatibility assessment. This study proposes a motor-driven torsional 3D-printed left ventricular simulator to reconstruct the hemodynamics of severe heart failure and related pathological conditions. The system integrates a 3D-printed elastic ventricular model with programmable torsional actuation, allowing the simulation of various cardiac conditions by adjusting the motor torsion angle and rotational speed, peripheral resistance and compliance. Fresh porcine blood was circulated for 4 h in a closed-loop system, with periodic measurements of plasma-free hemoglobin (PfHb), thrombin–antithrombin complex (TAT), and P-selectin. The results show that the system successfully reproduces typical hemodynamic features of severe heart failure, while hemolysis and coagulation markers remain low. After 4 h, PfHb was below 20 mg/dL, with no significant platelet activation or thrombosis. This study demonstrates that the proposed system enhances biomimicry while maintaining excellent hemocompatibility, offering a reliable platform for in vitro performance and safety evaluation of ventricular assist devices.