Heart Valve Delivery Catheter for Stepwise Stent Release
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing delivery systems for prostheses, particularly heart valves, face challenges such as complex crimping procedures, difficulty in maneuvering through tortuous vasculature, and inaccurate positioning due to the beating heart, leading to potential damage to tissue leaflets and increased procedural complexity.
Innovation Solution
A catheter system with a mechanism for sequential release of a stent, featuring axially movable sleeves and a stent holder, allowing for controlled deployment and positioning of prostheses like heart valves, with pre-loading capabilities to simplify the procedure and reduce operator skill requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the prosthesis is crimped to a small size to pass through the vasculature, then the delivery system can navigate narrow and tortuous pathways, but the tissue leaflets are negatively affected by long-term crimping
Solution Approach 1:
The prosthesis is loaded onto the catheter in the factory before sterilization, allowing the crimping to be performed once during manufacturing rather than during the surgical procedure. This preliminary crimping action eliminates repeated crimping and uncrimping cycles that would otherwise damage the tissue leaflets during loading and deployment in the operating room.
Solution Approach 2:
The catheter system includes a loading tool with a loading cone and compression elements that distribute the crimping force evenly across the prosthesis structure. This beforehand cushioning of forces prevents localized stress concentrations that would damage the delicate tissue leaflets during the crimping process.
2Reliability
If the prosthesis is loaded onto the catheter in the operating room by a trained operator, then the prosthesis can be freshly prepared, but the procedural complexity and operator skill requirements increase
Solution Approach 1:
The prosthesis comes pre-loaded onto the catheter in a sterile, factory-controlled environment. The entire assembly is designed as a self-contained unit that requires no manual loading operation by the surgeon. The prosthesis essentially serves itself by being permanently attached to the delivery catheter during manufacturing, eliminating the need for complex loading tools and trained operators to perform loading in the operating room.
Solution Approach 2:
The loading of the prosthesis onto the catheter is performed as a preliminary action during manufacturing rather than during surgery. This advance preparation transfers the complexity from the surgical procedure to the manufacturing process, where it can be controlled and standardized without requiring surgeon skill.
3Measurement precision
If the prosthesis is deployed in a stepwise fashion to control positioning, then the positioning accuracy is improved, but the deployment mechanism becomes more complex
Solution Approach 1:
The delivery catheter is divided into two functional segments: a fixed distal portion that remains stationary at the implantation site, and a movable proximal portion that can be advanced or retracted relative to the fixed portion. This segmentation allows the prosthesis to be deployed in a controlled stepwise fashion by moving only the proximal segment, achieving positioning accuracy without requiring complex multi-component deployment mechanisms.
Solution Approach 2:
The deployment mechanism utilizes dynamic movement of the movable catheter segment relative to the fixed segment. By dynamically adjusting the position of the movable segment during deployment, the system achieves precise control over prosthesis positioning while maintaining a relatively simple overall mechanism structure.
4Volume of moving object
If the catheter diameter is reduced to navigate narrow vasculature, then the minimally invasive approach is maintained, but the crimped prosthesis diameter is insufficient for adequate implantation
Solution Approach 1:
The prosthesis is nested within the catheter in a crimped state during delivery, allowing the entire assembly to pass through narrow vasculature via the femoral artery. Once positioned at the implantation site, the prosthesis is expanded from its crimped configuration to its full implantation diameter. This nesting approach allows the catheter to have a small delivery diameter while the prosthesis achieves its required large implantation diameter.
Solution Approach 2:
The prosthesis undergoes a parameter change in diameter from its crimped delivery state to its expanded implantation state. This parameter transformation allows the same prosthesis to fit within a small-diameter catheter for delivery while achieving the necessary large diameter for functional implantation, resolving the contradiction between catheter size and prosthesis size.
Data Source
AI summary
The present disclosure relates to a delivery catheter and the stepwise release of a stent from the catheter into the vasculature of a patient, as well as a loading device for a transcatheter heart valve (THV) prosthesis.