Engineered Heart Valve Tissue Formation at the Organ Level: Effects of Flow Dynamics on Tissue Development

Tissue engineered heart valve (TEHV) development protocols have yet to be optimized to an extent that can offer long-term function of value to patients, beyond contemporary clinical practices. One method of optimization may be possible through appropriate mechanical conditioning of the evolving engineered tissue before implantation. Engelmayr et al. [1] showed the synergistic benefits of combined flexural and fluid induced stresses on valvular-like tissue grown on rectangular scaffold strips. However, for clinical translation to be realized, it is important to determine if the nature of extracellular matrix production in such mechanistic studies also occurs at the macro-level, in the intact tri-leaflet valve geometry. Therefore, appropriate organ-level studies are required wherein the valvular tissues are subjected to the complex 3-dimensional flow/flexure/stretch regimes under highly controlled sub-, normal, and hyper-physiological flow levels. In this manner, biomechanical factors contributing to engineered tissue development can be coupled to tri-leaflet valve geometry requirements. In this study, one possible conditioning strategy on tri-leaflet TEHV structures is presented.