Expandable Stented Valved Tube Prosthesis for Child Growth
Solution Overview
Problem
Existing prostheses for replacing the right ventricular outflow tract in children do not grow with the child and require multiple open-heart surgeries to change the valve, and existing technologies do not allow for the percutaneous implantation of a valve in children, and existing technologies fail to accommodate the growth of the child in the child and require multiple reoperations to change and upsize the valve, and the use of the valve, and the use of the valve.
Innovation Solution
A transcatheter dilatable biostable polymeric stented valved tube prosthesis is provided with a tubular member capable of plastic deformation from a first dimension to a second dimension; a valve component having a plurality of leaflets. The valve component is capable of expansion from a first dimension to a second dimension, secured to an interior portion of the tubular member by an elastomeric glue at two circumferential portions defining an annular cavity therein. An expandable stent is positioned in the annular cavity between the valve component and the tubular member. The expandable stent is positioned in the annular cavity between the valve component and the tubular member. The cavity can also be filled with the same elastomeric glue material, such that the stent is embedded within the glue material which fills the inside of the cavity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a fixed-size prosthesis is implanted, then the valve structure is simple and easy to manufacture, but the child requires multiple reoperations as they grow
Solution Approach 1:
The prosthesis incorporates an expandable stent framework that allows the valve tube to dynamically increase in diameter from neonatal to adult size. The stent can be expanded using a balloon catheter through the femoral artery, transforming the device from a static to a dynamic structure that grows with the child without requiring multiple surgeries.
Solution Approach 2:
The prosthesis utilizes materials with specific mechanical properties that allow controlled expansion. The valve tube material and stent framework are designed to undergo permanent deformation when expanded, changing the dimensional parameter from a small neonatal size to a larger adult size while maintaining structural integrity throughout the growth period.
2Adaptability or versatility
If tissue-engineered valves are used, then the valve can grow with the child, but the structural stability is insufficient
Solution Approach 1:
The prosthesis combines multiple materials with complementary properties: a biostable polymeric valve tube material (such as ePTFE or polyurethane) provides structural stability and durability, while the elastomeric glue material provides flexibility and bonding. This composite construction ensures both growth accommodation through expansion and long-term structural stability of the valve leaflets.
Solution Approach 2:
The valve leaflets are designed with specific local properties including increased height of coaptation and length of free edge to maintain adequate coaptation length after expansion. The stent framework provides localized reinforcement at critical areas to maintain structural stability during expansion and throughout the child's growth.
3Duration of action of stationary object
If conventional prostheses are used, then the valve is durable, but thromboembolic complications and calcification occur
Solution Approach 1:
The prosthesis uses biostable polymeric materials with specific surface properties and composition that resist thrombus formation and calcification. The material selection and surface treatment are designed to maintain hemocompatibility over time, preventing the harmful effects associated with conventional prostheses while maintaining durability.
Solution Approach 2:
The prosthesis is designed as a single-use, lifelong implant that replaces the need for multiple reoperations. By providing a durable valve that grows with the child and eliminates the need for repeated surgeries, it avoids the cumulative harmful effects of multiple implantations including thromboembolic complications and calcification.
4Ease of operation
If transcatheter valve implantation is performed, then the procedure is minimally invasive, but the vessels are hypoplastic and cannot accommodate the valve
Solution Approach 1:
The prosthesis is designed to be implanted in a minimally invasive manner through the femoral artery and then expand to its final size. The stent framework can be expanded using a balloon catheter, allowing the valve to grow from a small implantable size to its final adult size through a minimally invasive transcatheter procedure, overcoming the limitation of hypoplastic vessels.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The prosthesis can be implanted surgically and then expanded to match the growth of the child, avoiding multiple reoperations and maintaining valve integrity and functionality despite expansion, with a durable and sutureless connection between the valve and conduit.
Implementation Method 1
a tubular member capable of plastic deformation from a first dimension to a second dimension
Implementation Method 2
the valve component is secured to an interior portion of the tubular member by an elastomeric glue material
Implementation Method 3
An expandable stent is positioned in the annular cavity between the valve component and the tubular member
Data Source
AI summary
A transcatheter dilatable valve tube prosthesis is provided including a tubular member capable of plastic deformation from a first dimension to a second dimension; a valve component having a plurality of leaflets. The valve component is capable of expansion from the first dimension to the second dimension, and the valve component is secured to an interior portion of the tubular member by an elastomeric glue at two circumferential portions defining an annular cavity therein. An expandable stent is positioned in the annular cavity between the valve component and the tubular member.