Development of Artificial Heart Valve with a Membranous Cusp (Influence of Mechanical Anisotropy)

Abstract

We have been developing heart valve-like tissues (Biovalve) using in-body tissue architecture. Previously, we fabricated a novel prosthetic valve with a membranous tissue (Biosheet) as a valve cusp and an elliptical valve annulus. Because of isotropic mechanical properties of the valve, it was difficult to satisfy the performance of both opening and closing. The purpose of this study is to clarify the influence of mechanical property of anisotropic cusp on valve performance.The valve models were fabricated from a combination of polyurethane sheets and Ni-Ti wires. In-Vitro simulation was performed to evaluate valve performance and to observe its opening-closing behavior. The experimental conditions were set at the physiological condition of healthy adult male. According to ISO5840, temporal waveform of left atrial pressure, left ventricular pressure and mitral regurgitation were measured, and regurgitation rate, mean pressure gradient and effective orifice area were calculated to evaluate the valve performance.