Triple Balloon Catheter for In Situ Biodegradable Stent Formation
Solution Overview
Problem
Current stent technologies face high failure rates due to neointimal hyperplasia and acute arterial thrombosis, with drug-eluting stents showing increased in-stent thrombosis and limited re-endothelialization, while pre-formed biodegradable stents struggle with external radial force, compressibility, and delivery system challenges.
Innovation Solution
Development of catheters for forming liquid cast biodegradable arterial stents using multiple balloon occlusion and infusion catheters, which include a proximal and distal occlusion balloon, a middle balloon, and elements for delivering light or heat to initiate polymerization of a polymer solution within the artery, creating a stent that is biodegradable and can inhibit thrombosis and neointimal hyperplasia.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If drug-eluting stents are used to prevent neointimal hyperplasia, then restenosis is reduced, but in-stent thrombosis rate increases and re-endothelialization is delayed
Solution Approach 1:
The patent changes the chemical parameters of the stent material by using biodegradable polymers with specific degradation rates and properties. The polymer composition and degradation kinetics are carefully controlled to provide mechanical support initially, then gradually degrade to allow natural healing processes, avoiding the thrombogenic effects of permanent metal stents and the excessive inhibition of drug-eluting stents.
Solution Approach 2:
The patent employs composite material strategies by combining biodegradable polymer matrices with controlled drug delivery systems. The stent consists of multiple functional components including the structural polymer framework, embedded anti-proliferative drugs, and potentially endothelialization-promoting agents, creating a multi-functional composite structure that addresses multiple clinical concerns simultaneously.
2Object-affected harmful factors
If pre-formed biodegradable stents are used to address thrombosis and re-endothelialization issues, then biocompatibility improves, but external radial force, compressibility, and delivery system complexity worsen
Solution Approach 1:
The patent divides the stent into multiple segments or struts that can be independently formed and then assembled. This segmentation allows each component to be optimized for biocompatibility while the overall structure maintains mechanical integrity. The segmented approach also simplifies the delivery system as components can be delivered separately and self-assemble at the target site.
Solution Approach 2:
The patent replaces complex mechanical delivery systems with chemical or self-assembly mechanisms. Instead of using sophisticated compression and expansion mechanisms, the stent components are designed to self-assemble through chemical bonding or physical interactions after delivery, significantly simplifying the delivery system while maintaining stent functionality.
3Strength
If liquid cast biodegradable stents are formed in situ using multiple balloon occlusion catheters, then radial force and compressibility are optimized, but device complexity and procedure time increase
Solution Approach 1:
The patent merges multiple functions into a single integrated catheter system. The delivery catheter incorporates both the balloon occlusion mechanism and the liquid polymer deposition system, allowing simultaneous structural formation and material deposition. This integration reduces the number of separate devices needed while maintaining the ability to optimize radial force and compressibility through controlled polymer casting.
4Manufacturing precision
If light or heat elements are added to initiate polymerization of polymer solution, then stent formation control improves, but device complexity and energy requirements increase
Solution Approach 1:
The patent introduces intermediary substances such as photoinitiators or thermal initiators that mediate the polymerization process. These intermediaries have low activation energies and can trigger polymerization with minimal external energy input. The initiators are incorporated into the polymer solution before delivery, allowing controlled polymerization to occur immediately after deposition with minimal additional energy requirements.
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 catheter system enables the formation of biodegradable stents that provide sufficient radial force, inhibit thrombosis, and promote re-endothelialization, addressing the limitations of existing stent technologies by forming stents in situ with optimal mechanical properties and biocompatibility.
Implementation Method 1
an element for delivering light such as UV light or visible light which promote or initiate curing of the solution (e.g., via polymerization or cross-linking)
Implementation Method 2
elements for delivering heat, which promotes or initiates curing of the solution (e.g., via polymerization or cross-linking)
Implementation Method 3
the proximal occlusion balloon and distal occlusion balloon when inflated define an interior space within an artery between the inflated proximal occlusion balloon and the inflated distal occlusion balloon
Data Source
AI summary
Disclosed are balloon catheters for forming liquid cast biodegradable arterial stents, typically, the balloon catheters include multiple balloons and multiple ports and include an element for promoting or initiating curing of a polymer solution via polymerization or cross-linking.