Design, development, testing at ISO standards and in vivo feasibility study of a novel polymeric heart valve prosthesis

Abstract

<p>A novel polymeric heart valve shows durability equivalent to 25 years in accelerated bench testing, <italic>in vitro</italic> hydrodynamics equivalent to existing bioprosthetic valves; and good performance in a small acute feasibility study in sheep.</p>

Engineering Efforts to Refine Compatibility and Duration of Aortic Valve Replacements: An Overview of Previous Expectations and New Promises

“…Polymeric valves are manufactured with elastomeric polymers by a simple fabrication procedure using molds. Typically, the process involves “injection molding” whereby synthetic (e.g., polyurethane or polystyrene) ( 29 , 30 ) or natural polymers (e.g., fibrin) ( 31 ) are injected into tri-leaflet molds that give rise to complete sutureless valves, and can be readily mounted onto posts for implantation. This design provides advantages including easy scalability, low cost, natural hemodynamic performance and a relatively high long-term durability comparable to that of mechanical prostheses ( 32 ).…”

“…Moreover, 0.1 mm PTFE valves were characterized by higher leaflet mobility and lower transvalvular gradients ( 36 ). Stasiak et al ( 29 ) recently introduced the so-called Poli-Valve ( 38 )-a styrene triblock copolymer valve obtained by injection molding. This technique, besides being inexpensive and highly reproducible, appears to allow an optimal anisotropic distribution of forces on the leaflets and the polymeric fibers ( 39 , 40 ) resulting in maximal mechanical durability due to a similar collagen fiber orientation to that of native heart valve tissue ( 39 ).…”

Recent progress in biomaterials for heart valve replacement: Structure, function, and biomimetic design

“…With the rapid development of material science, polymeric aortic valves are considered to be a competitive candidate for the aortic valve prosthesis that could eliminate shortcomings of the existing artificial heart valves. 2,3,20,46,[69][70][71][72][73][74][75][76][77][78] Researchers have been trying to develop ideal polymeric heart valve for decades. Trace back to the 1960s, the first polymeric heart valve has been implanted into the human body.…”

“…The flow's influence would be prominent when the polymer itself could assemble to anisotropic microstructure, for example, due to the segregation of the styrenic and elastomeric blocks, the styrenic triblock copolymers with a styrene content of about 20% to 33% can selfassemble into cylindrical microstructure with well-defined diameter and spacing. 73 When under melted processing, these polymers molecular could be orientated by the flow and produce structural anisotropy in the obtained materials. 2,71,74,77,78 According to this, Joanna Stasiak et al 72 reported a slow injection molding method to achieve ordered microstructure of cylindrical block copolymers.…”

“…This fabrication of polymeric heart valve has been developed over the recent years. A novel heart valve prosthesis with the feasibility study has been reported recently, 73 were fabricated from the styrenic triblock copolymers poly(styrene-block-ethylene/propylene-block-styrene) (SEPS) and poly(styrene-block-ethylene/butylene-blockstyrene) (SEBS) with the slow injection molding method. Figure 5B shows an orientation map of the artificial heart valve leaflet obtained by SAXS, again, the direction and the length of the vector represent the orientation direction of the molecular and the proportional of the degree of orientation, respectively.…”