Transapical Self-Expanding Valve Anchoring via Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for replacing cardiac valves are invasive, require prolonged hospitalization, and involve significant complexities and costs, with existing stent-supported systems facing issues with migration, sealing, and adaptation to irregular cardiac ring surfaces, and often necessitate extracorporeal circulation or temporary heart stopping.
Innovation Solution
A catheter system for delivering a self-expandable heart prosthesis with a prosthetic valve assembly that includes a central expandable band and discrete anchors, allowing for precise anchoring and sealing, and the ability to adapt to varying cardiac ring diameters and irregular surfaces, using a push-forward sheath for antegrade delivery and a pusher tube for active expansion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If stent-supported systems are used for valve positioning, then the valve can be delivered percutaneously, but migration from the target valve site occurs due to inadequate anchoring
Solution Approach 1:
The prosthesis is divided into distinct functional segments: a central band for valve support, separate anchors for anchoring, and a sealing element for sealing. This segmentation allows each component to perform its specific function optimally - the anchors provide secure anchoring to prevent migration while the central band supports the valve, and the sealing element addresses leakage independently.
Solution Approach 2:
The sealing element acts as an intermediary component positioned between the prosthesis and the irregular cardiac ring surface. This sealing element mediates the interface, adapting to surface irregularities and calcifications to provide effective sealing without requiring direct contact between the rigid stent structure and the irregular native tissue.
2Productivity
If conventional stents are used, then valve replacement can be performed, but sealing quality is poor due to irregular and calcified cardiac ring surfaces
Solution Approach 1:
Different parts of the prosthesis have different local qualities tailored to their specific functions. The sealing element is designed with compliant, adaptable material properties to conform to irregular surfaces, while the central band provides rigid structural support, and the anchors offer firm anchoring. This local differentiation of properties optimizes sealing at the interface with irregular cardiac ring surfaces.
3Ease of manufacture
If fixed-diameter stents are used, then manufacturing is simplified, but adaptation to varying vessel wall diameters is limited
Solution Approach 1:
The prosthesis incorporates dynamic, self-adjusting features that allow it to adapt to varying anatomical conditions. The sealing element and central band can dynamically adjust their configuration to match the actual diameter and shape of the cardiac ring, providing optimal fit and sealing without requiring multiple fixed-diameter options.
4Ease of operation
If balloon expansion is used for stent deployment, then the valve can be positioned, but trauma to fragile valve tissue occurs
Solution Approach 1:
The prosthesis employs self-expanding anchors that automatically expand to their functional configuration upon deployment, eliminating the need for external balloon expansion. This self-service mechanism allows the anchors to expand gently against the tissue, positioning the valve without subjecting fragile valve tissue to the high pressures and mechanical trauma associated with balloon inflation.
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
Enables minimally invasive cardiac valve replacement with reduced migration risk, improved sealing, and adaptation to individual anatomy, potentially reducing hospital stay and procedural complexity while avoiding extracorporeal circulation.
Implementation Method 1
self-expandable prosthesis that can be compressed into a delivery catheter and then expanded to a functional state
Data Source
Figure 1~3
Figure 4~10
Figure 5~8
AI summary
A prosthetic valve assembly for use in replacing a deficient native valve comprises a replacement valve (820) supported on an expandable prosthesis frame. The valve (820) may be delivered transluminally or transmyocardially using a thorascopic or other limited access approach using a delivery catheter (920). Preferably, the initial partial expansion of the valve (820) is performed against the native valve annulus (916) to provide adequate anchoring and positioning of the valve (820) as the remaining portions of the valve (820) expand. The valve (820) may be be delivered using a retrograde or antegrade approach. When delivered using a retrograde approach, a delivery catheter (920) with a pull-back sheath (922) may be used, while antegrade delivery is preferably performed with a delivery catheter (920) with a push- forward sheath (922) that releases the proximal end of the valve (820) first.