Coiled Valve Restraint for Short-Path Prosthetic Valve Delivery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing prosthetic valve delivery systems face challenges in navigating tortuous vascular pathways with limited deployment area and require a high degree of lateral flexibility to minimize cross-sectional area and length, especially when deploying through minimally invasive methods.
Innovation Solution
A valve delivery system featuring an inner shaft with an elongated tension member that coils around the prosthetic valve to maintain it in a compressed state, allowing for releasable deployment by uncoiling and expanding the valve at the target site, minimizing the need for a lengthy deployment path.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If a traditional delivery catheter with coaxial inner tube and outer tube sheath is used, then the prosthetic valve can be delivered through the vascular system, but the deployment site requires a length equivalent to the length of the prosthetic valve plus the length of the capsule, increasing the required deployment area
Solution Approach 1:
The patent extracts and eliminates the outer tube sheath from the traditional delivery system, retaining only the inner tube as the delivery catheter. This removal of the sheath component directly reduces the deployment site length requirement while maintaining the essential delivery function through the vascular system
Solution Approach 2:
The delivery system is segmented into distinct functional components: the delivery catheter (inner tube) for navigation and positioning, and the self-expanding stent-graft with its own expansion mechanism. This segmentation allows the stent-graft to expand independently at the target site without requiring the sheath to be withdrawn over its entire length
2Adaptability or versatility
If the delivery system is designed to navigate tortuous vascular pathways, then access to the target site is achieved, but the system requires greater length and cross-sectional area, reducing lateral flexibility
Solution Approach 1:
The delivery catheter is designed with flexible materials and a thin-walled construction that allows it to bend and conform to tortuous vascular pathways. This flexibility enables navigation through complex anatomy without requiring excessive system length or cross-sectional area
Solution Approach 2:
Instead of making the entire delivery system long and rigid to ensure structural integrity, the patent inverts the approach by using a short, flexible catheter that relies on the self-expanding properties of the stent-graft for structural support during and after deployment
3Manufacturing precision
If the sheath is fully withdrawn to deploy the prosthetic valve, then the valve expands to conform with the blood vessel wall, but the process requires extensive sheath withdrawal distance, increasing the deployment area
Solution Approach 1:
The stent-graft is designed with self-expanding properties that allow it to automatically expand to its native configuration once released from the delivery catheter. This self-service expansion mechanism eliminates the need for extensive sheath withdrawal, as the valve expands in place through its inherent elastic memory rather than being pushed by sheath retraction
Solution Approach 2:
The stent-graft is pre-formed and self-expanded outside the body, then compressed into a small profile for delivery. This preliminary preparation allows the device to be delivered in a compact state and then rapidly expand at the target site without requiring long sheath withdrawal distances
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 efficient delivery of prosthetic valves through complex vascular anatomy with reduced invasiveness and flexibility, facilitating deployment without extending beyond the length of the prosthetic valve, thus enhancing procedural efficiency and minimization of invasive procedures.
Implementation Method 1
employ a suitable elastic material such as stainless steel or nitinol (nickel-titanium)
Implementation Method 2
Nitinol may additionally employ shape memory properties
Implementation Method 3
permitted to expand upon removal of a restraint to an expanded or natural state
Data Source
AI summary
A valve delivery system and valve delivery method are disclosed. The valve delivery system includes an inner shaft extending along a longitudinal axis and an elongated tension member to continuously circumferentially coil around a prosthetic valve disposed on the inner shaft to form a sheath portion to releasably contain the prosthetic valve on the inner shaft in a compressed state, the elongated tension member extending from the sheath portion along the longitudinal axis of the inner shaft.