Innovations in Polymer Leaflets for Prosthetic Heart Valves

Flexible synthetic leaflets for prosthetic heart valves that promote tissue ingrowth to reduce complications like thrombus formation. The leaflets have a composite structure with a porous synthetic membrane filled with a material that inhibits tissue growth. This inner layer is covered by an outer layer that promotes tissue ingrowth. The inner layer prevents excessive tissue growth, while the outer layer encourages normal tissue ingrowth. The composite structure allows tissue ingrowth while avoiding excessive tissue entanglement in the leaflets.

Prosthetic heart valve made from a composite material containing fibrous reinforcements that resist calcification and tearing. The valve leaflet includes electrospun fibers embedded in a polymer matrix. The fibers can be composed of different materials to provide tailored physical and mechanical properties. The polymer matrix can be a polyisobutylene urethane copolymer for chemical inertness.

Prosthetic heart valves with improved leaflet motion and durability using synthetic materials. The synthetic materials are treated by heat setting at specific temperatures and times to bias the leaflets towards either the closed or open position. This helps the valve coapt and seal better. The heat treatment forms a three-dimensional geometry in the leaflets that aids in motion and coaptation. The heat setting can be done before attaching the leaflets to the valve structure.

Prosthetic heart valves with improved durability and reduced calcification compared to traditional valves made from animal tissue. The valves have leaflets made from composites, fabrics, or meshes instead of natural tissue. The composites have a metal substrate with openings coated with a polymer. The fabrics and meshes are made from fine metal wires or braided/knitted metal structures. The valves can also have leaflets made from preserved natural tissue like pericardium that has been plastinated to replace the water and fat with a biocompatible polymer.

Implantable prosthetic heart valves that can be delivered in a compressed state and expanded to full size after deployment to reduce the size of the delivery catheter. The valves have a stent frame with deflectable struts that can transition between contracted and expanded states. The valve body has flexible polymeric leaflets. The valve can be made using a dip casting process where the stent is dipped in wet polymer and cured, then the leaflets are formed by dipping a mold in wet polymer and curing. The stent and leaflets are assembled to complete the valve.

Composite leaflet material for artificial heart valves that have improved durability and reduced wrinkling compared to conventional materials. The composite material is formed by combining an expanded fluoropolymer membrane with an elastomer. The elastomer fills the pores of the expanded fluoropolymer. The composite leaflets made from this material exhibit elongation while maintaining strength and then increase in stiffness beyond a certain strain. This provides flexibility during valve opening without excessive wrinkling, and resistance to tearing or failure during long-term cyclic operation.

Manufacturing prosthetic heart valves with artificial polymeric leaflets that aims at improving the manufacturability and consistency of these valves. The manufacturing involves applying a liquid polymer to the valve frame and a leaflet formation structure, partially curing the polymer in a humidity chamber, then fully curing it in another chamber. This allows the thickness of the leaflets to be precisely controlled. An identifier is marked on the valve frame to track and optimize the manufacturing process.

Valved conduits for implantation in vessels to replace damaged heart valves. The valved conduits have a collapsible design for delivery and deployment. The conduits can have multiple layers with one layer being biodegradable. The valves are attached to the inner surface of the conduits. The valve leaflets are made from layers of material that are anisotropic with offset orientations. This allows the leaflets to flex and open properly in the expanded conduit shape. The conduits can have a stent design with chevron-shaped structures that collapse and expand well. The stent design allows non-stretchable conduits and valves.

Replacement heart valves with polymeric leaflets that have improved durability and hemodynamic performance compared to biological tissue valves. The leaflets are made of multiple polymers with a composition gradient along a portion of the leaflet. This gradient allows each leaflet to have a desired stiffness profile for better durability and matching natural valve behavior. The polymers can also have fibers embedded to provide support and anisotropic mechanical properties.

Prosthetic heart valves with pre-stressed fibers in the leaflets to improve durability and mimic native valve behavior. The leaflets are composite materials with layers of pre-stressed fibers sandwiched between polymer layers. The fibers are tensioned or compressed before assembly. This provides the leaflets with anisotropic properties and spring-like tension. The pre-stress reduces the likelihood of over-stretching during heart contractions. The pre-stressed fibers also create a curved, accordion or folded configuration in the relaxed leaflet state. This emulates the natural collagen fibers in native valves.

Prosthetic valve leaflets for implantation in body passages like blood vessels that have regions with different properties to facilitate tissue ingrowth and integration into the vessel wall. The leaflet has an inner synthetic polymeric segment that extends into the vessel lumen and a peripheral segment made of a remodelable material like collagen to promote tissue ingrowth. The peripheral segment contacts the vessel wall to promote integration. This allows the valve leaflet to anchor itself to the vessel wall and prevent dislodgement.