Mechanical and Structural Properties of a Novel Hybrid Heart Valve Scaffold for Tissue Engineering

Abstract

Hybrid heart valve scaffolds were fabricated from decellularized porcine aortic heart valve matrices and enhanced with bioresorbable polymers using different protocols: (i) dip coating of lyophilized decellularized matrices, and (ii) impregnation of wet decellularized matrices. The following polymers were evaluated: poly(4-hydroxybutyrate) and poly(3-hydroxybutyrate-co4-hydroxybutyrate). Tensile tests were conducted to assess the biomechanical behavior of valve leaflet strips. Suture retention strength was evaluated for the adjacent conduit. A pulse duplicator system was used for functional testing of the valves under physiological systemic load conditions. The properties of the hybrid structures were compared with native, decellularized, and glutaraldehyde-fixed specimens. Mechanisms of the polymer impregnation process were studied with IR spectroscopy, fluorescent microscopic imaging, and SEM. Altogether this study demonstrates the feasibility and improved biomechanical function of a novel hybrid heart valve scaffold for an application in tissue engineering.

Engineering of a polymer layered bio-hybrid heart valve scaffold

“…Earlier studies reported that PGA resulted in high degradation rate while PHA showed increased risk of premature mechanical failure [24]. Other commonly used polymers for TEHV such as poly (ester urethane) urea (PEUU), poly-hydroxybutyrate (PHB) and its co polymers combined with natural ECM corroborated better biomechanical properties [16,25,26]. These studies displayed superior mechanical properties but did not provide evidence for retention of tissue in its native hydrated form.…”

Characterization of new isolated Ralstonia eutropha strain A-04 and kinetic study of biodegradable copolyester poly(3-hydroxybutyrate-co-4-hydroxybutyrate) production

“…It has been reported that P(3HB-co-4HB)s have been tried in applications in soft tissue engineering due to their unique mechanical properties [8]. Recently, P(3HB-co-4HB) has been found to be useful in biomedical applications [14].…”

Effects of decellularization on the mechanical and structural properties of the porcine aortic valve leaflet

“…Commonly used decellularization methods are a non-ionic detergent, Triton X-100, (tert-octylphenylpolyoxyethylen) [16,21,25], an anionic detergent, SDS (sodium dodecyl sulfate) [20], and an enzymatic agent, Trypsin [15,18,22,26,27]. To understand the mechanics of decellularized valve leaflets, Korossis et al [20] measured the leaflet strips cut along the circumferential or the radial direction and found that after treatment with SDS (hypotonic buffer), extensibility and failure strain of circumferential strips significantly increased, while in the radial strips, there was some increase but not significantly [20].…”