Polyurethane Knit Composite Heart Valve Leaflets for Durability

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing synthetic heart valve prostheses face challenges in achieving long-term durability, biocompatibility, and hemodynamic performance due to limitations in material selection and manufacturing methods, leading to issues like calcification, thrombosis, and paravalvular leakage.

Innovation Solution

A composite sheet made from a polyurethane elastomer reinforced with biocompatible polymer fibers, specifically a knit fabric coated with polyurethane, providing enhanced mechanical properties and biocompatibility, mimicking the anisotropic behavior of natural heart valve leaflets.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If bioprosthetic valves are used to avoid anticoagulation medication, then patient quality of life improves, but valve durability decreases to 7-10 years due to calcification and stiffening

Engineering Contradiction:

Improvethrombosis and anticoagulation requirementVSAvoidvalve lifetime

Core Design Contradiction:

Object-affected harmful factorsVSDuration of action of stationary object

Solution Approach 1:

The patent applies composite materials by combining synthetic polyurethane base material with biocompatible polymer fibers (such as PTFE, PEEK, or aramid fibers) to create a hybrid structure. This composite construction provides both the biocompatibility needed to avoid thrombosis and the mechanical strength required for long-term durability, resolving the contradiction between avoiding anticoagulation and achieving extended valve lifetime.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent utilizes parameter changes by implementing crosslinking of the polyurethane matrix through chemical or physical methods, which fundamentally alters the material's degradation resistance. This crosslinking transformation increases structural stability and calcification resistance while maintaining flexibility, thereby extending valve durability without compromising biocompatibility.

Inventive Principle:

Principle #35Parameter changes

2Duration of action of stationary object

If synthetic materials are used to extend valve lifetime, then durability improves, but biocompatibility and hemocompatibility worsen due to calcification and thrombosis

Engineering Contradiction:

Improvevalve lifetimeVSAvoidcalcification and thrombosis

Core Design Contradiction:

Duration of action of stationary objectVSObject-affected harmful factors

Solution Approach 1:

The patent employs composite materials by integrating biocompatible polymer fibers (PTFE, PEEK, or aramid) within a polyurethane matrix. This composite structure provides enhanced durability while the specific fiber materials selected ensure resistance to calcification and thrombosis, thus achieving extended lifetime without compromising biocompatibility.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent applies parameter changes through crosslinking the polyurethane matrix, which modifies the material's chemical and physical properties to resist degradation, calcification, and thrombosis. This crosslinked structure maintains long-term stability while preserving the necessary flexibility and biocompatibility for blood contact.

Inventive Principle:

Principle #35Parameter changes

3Ease of operation

If minimally invasive implantation is used, then patient recovery time improves, but device profile requirements increase, necessitating thinner materials that compromise long-term performance

Engineering Contradiction:

Improveimplantation invasivenessVSAvoidmaterial longevity

Core Design Contradiction:

Ease of operationVSDuration of action of stationary object

Solution Approach 1:

The patent applies composite materials that provide high strength-to-thickness ratio by combining polyurethane with reinforcing biocompatible fibers. This allows the valve to be made thinner for minimally invasive delivery while the fiber reinforcement ensures long-term mechanical performance and durability are not compromised.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent utilizes parameter changes through crosslinking the polyurethane matrix, which significantly enhances the material's mechanical properties and degradation resistance. This allows thinner wall thickness suitable for minimally invasive implantation while maintaining or improving long-term durability through the crosslinked structure's enhanced strength and stability.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS12478711B2Composite sheets and medical implants comprising such sheets

Publication Date: 2025.11.25 DSM IP ASSETS BV

AI summary

Disclosed herein are composite sheets and prosthetic medical devices formed therefrom. In an embodiment, a composite sheet has a thickness of 25-250 μm and comprises 10-70 mass %, based on the total mass of the composite sheet, of a knit fabric having thickness of 15-225 μm and comprising strands of 2-50 dtex, the strands comprising biocompatible polymer fibers, the strands comprising biocompatible polymer fibers, wherein the fabric comprises a thickness in a plurality of first locations, and pores in a plurality of second locations; and 30-90 mass %, based on the total mass of the composite sheet, of a polyurethane coating, wherein the polyurethane coating coats the fabric and fills the pores of the fabric such that the composite sheet is substantially impermeable to water.