Bench Models for Assessing the Mechanics of Mitral Valve Repair and Percutaneous Surgery

Abstract

Rapid preclinical evaluations of mitral valve (MV) mechanics are currently best facilitated by bench models of the left ventricle (LV). This review aims to provide a comprehensive assessment of these models to aid interpretation of their resulting data, inform future experimental evaluations, and further the translation of results to procedure and device development. For this review, two types of experimental bench models were evaluated. Rigid LV models were characterized as fluid-mechanical systems capable of testing explanted MVs under static and or pulsatile left heart hemodynamics. Passive LV models were characterized as explanted hearts whose left side is placed in series with a static or pulsatile flow-loop. In both systems, MV function and mechanics can be quantitatively evaluated. Rigid and passive LV models were characterized and evaluated. The materials and methods involved in their construction, function, quantitative capabilities, and disease modeling were described. The advantages and disadvantages of each model are compared to aid the interpretation of their resulting data and inform future experimental evaluations. Repair and percutaneous studies completed in these models were additionally summarized with perspective on future advances discussed. Bench models of the LV provide excellent platforms for quantifying MV repair mechanics and function. While exceptional work has been reported, more research and development is necessary to improve techniques and devices for repair and percutaneous surgery. Continuing efforts in this field will significantly contribute to the further development of procedures and devices, predictions of long-term performance, and patient safety.

Biomimetic six-axis robots replicate human cardiac papillary muscle motion: pioneering the next generation of biomechanical heart simulator technology

“…The simulators feature programmable pumps that expose heart valves to their physiologic environment-including relevant pressure and flow waveforms-while haemodynamic, strain and motion metrics are recorded. Numerous previous studies feature analyses of disease states and optimization of surgical valve repair techniques and devices [1][2][3][4][5][6][7][8]. These studies are unique in their ability to immediately inform the current practice of cardiac surgery and have already had a meaningful impact on patient care through the analysis of surgical repairs [9,10].…”

Effects of annular contraction on anterior leaflet strain using an in vitro simulator with a dynamically contracting mitral annulus

“…For functional MR (FMR), the MV maintains a normal anatomy with pathological structure/geometry (Schmitto et al, 2010). This allows in vitro models to be more advantageous due to their ability to use readily-accessible, healthy MVs and easily modify their geometry for different experiments, all while maintaining the valve’s subvalvular anatomy (Siefert and Siskey, 2015).…”