Structural reinforcements as a strategy toward durable polymeric heart valves

Valvular heart diseases are commonly addressed by the implantation of heart valve replacement devices; however, current prosthetics remain suboptimal in their performance and longevity, often necessitating multiple operations. Here, structurally reinforced polymeric heart valves are fabricated, utilizing a combination of dip coating and 4-axis three-dimensional printing with different grades of elastomeric polyurethanes. This strategy introduces mechanical anisotropy, increases toughness nearly 9-fold, and enhances fatigue resistance with a 150% increase in the energy required for tear propagation. While all valves exceed the ISO 5840-2 standard, structural reinforcement prevents the progression of tears during accelerated cardiac cycling and reduces regurgitation by about 50% compared with unreinforced valves without compromising opening performance. Subsequently, we demonstrate a valved conduit to broaden the possible clinical applications of this design. These structurally reinforced polymeric heart valve replacements could offer improved device performance and resistance against tear propagation, thus providing a vital window for necessary clinical interventions.