Development of a mechano-mimetic mitral valve – hybrid experimental and finite element analysis findings

Mitral valve mechanics play a significant role in its function and alterations in mechanics are classical indicators of valvular disease. In-vivo large animal models are inherently limited for the study of mitral mechanics, as they lack pathology, anatomical consistency and reproducibility. In-vitro flow rigs with ex-vivo specimens have similar issues. Synthetic mitral valves are being developed for flow examinations, but to-date lack anisotropy and capacity for physiological pressures and flow simultaneously. In this work, a mechano-mimetic synthetic mitral valve with anisotropic leaflet mechanical properties is presented with experimental findings and complemented by finite element predictions. Attaining peak systolic transmitral pressures exceeding 120 mmHg with flow rates greater than 3.5 L/min, this represents a significant advancement over existing synthetic approaches. This low-cost physical model addresses the compelling need for anatomically representative, repeatable, and durable synthetic mitral valves with precise control over leaflet thickness and incorporating anisotropic material properties to advance our understanding mitral mechanics. STATEMENT OF SIGNIFICANCE: Synthetic mitral valves models are an increasingly important tool in studying mitral valve mechanics. However, there are few models available currently, most of which have limitations such as lack of anisotropy, precise control over leaflet thickness, reproducibility, and/or capability to replicate physiological flows. The mechano-mimetic mitral valve presented in this study is the first of its kind to be anisotropic, anatomically representative with precise control over leaflet thickness and chordae attachment, and reproducible. The separate chordae allow adjustment of chordae tension individually and proper closure of the valve, leading to physiological pressures and flow inside the flow rig. This work paves the way for more representative synthetic mitral valve models and realistic experimental simulations of mitral valve mechanics.