Cryoablation Catheter Flow Splitting for In-Catheter Precooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cryoablation technologies face challenges in achieving efficient, safe, and reliable precooling of refrigerant fluid for cryoprobes, often requiring separate supply lines, mechanical valves, and are prone to temperature gradients and safety risks, especially in disposable devices.
Innovation Solution
A cryoablation catheter assembly that splits the refrigerant flow into therapeutic and precooling portions using a heat exchanger within the catheter, allowing adjustable precooling power without separate supply lines, utilizing a flow splitter and heat transfer structure to maintain precise temperature control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If external precooling methods are used to achieve temperatures significantly below freezing point, then precooling effectiveness is improved, but temperature gradients occur between piping and ambient causing significant loss of cooling power
Solution Approach 1:
The patent merges the precooling function and therapeutic function into a single integrated catheter assembly. The precooling heat exchanger and therapeutic cryo-applicator are combined in one device, allowing precooling to occur at the application site rather than requiring separate external precooling lines that would create temperature gradients and cooling power losses.
Solution Approach 2:
The precooling heat exchanger performs preliminary cooling of the refrigerant flow before it reaches the therapeutic cryo-applicator. This preliminary action occurs within the catheter assembly itself, ensuring the refrigerant is already cooled to the required temperature before therapeutic application, eliminating the need for extensive external precooling infrastructure.
2Measurement precision
If separate supply lines are used for precooling and therapeutic flow, then precooling control is improved, but device complexity increases and compatibility with standard refrigerant connection lines is lost
Solution Approach 1:
The patent segments the refrigerant flow within a single supply line using a flow splitter. The flow splitter divides the refrigerant into a precooling flow portion and a therapeutic flow portion, allowing separate control of each function while maintaining compatibility with standard single-line refrigerant connection interfaces.
Solution Approach 2:
The single supply line is designed to perform multiple functions: it delivers refrigerant to both the precooling heat exchanger and the therapeutic cryo-applicator. This multi-functional design maintains compatibility with standard refrigerant connection lines while enabling both precooling and therapeutic operations through one universal interface.
3Measurement precision
If mechanical valves are used to control refrigerant flow splitting, then flow control precision is improved, but reliability decreases due to mechanical wear and safety risks
Solution Approach 1:
The patent replaces mechanical valves with a flow splitter that uses fluid dynamics and heat exchange principles to control refrigerant flow distribution. The flow splitter passively divides the refrigerant flow between precooling and therapeutic portions based on thermal gradients and pressure differentials, eliminating moving parts and mechanical wear while maintaining reliable flow control.
Solution Approach 2:
The flow splitting mechanism is self-regulating based on the thermal state of the system. As the precooling heat exchanger cools the refrigerant, natural convection and pressure differentials automatically adjust the flow distribution between precooling and therapeutic portions, requiring no external mechanical control components.
4Extent of automation
If solenoid valves are used for flow control, then automation is improved, but temperature control deteriorates due to valve warming of refrigerant
Solution Approach 1:
The patent eliminates solenoid valves by using a passive flow splitter mechanism that relies on thermal and pressure gradients rather than electromagnetic actuation. This avoids the heat generation inherent in solenoid operation, preventing unwanted warming of the refrigerant while still enabling automated flow control through the thermal dynamics of the precooling process itself.
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 effective precooling of the therapeutic flow portion within the catheter, reducing the need for mechanical components and ensuring safe, reliable operation across varying ambient conditions.
Implementation Method 1
a precooling arrangement comprising a heat exchanger configured to apply an adjustable precooling power from the precooling flow portion to the therapeutic flow portion
Implementation Method 2
a flow splitter configured to split the input flow into a therapeutic flow portion and a precooling flow portion
Data Source
AI summary
A cryoablation catheter assembly is described. The assembly comprises (a) an inlet for receiving an input flow of refrigerant fluid, (b) a cryo-applicator, (c) a flow splitter configured to split the input flow into a therapeutic flow portion and a precooling flow portion, and (d) a precooling arrangement configured to precool the therapeutic flow portion and guide the precooled therapeutic flow portion towards the cryo-applicator, wherein the precooling arrangement comprises a heat exchanger configured to apply an adjustable precooling power from the precooling flow portion to the therapeutic flow portion. Furthermore, a cryoablation system and a method are described.