Rapid Exchange Balloon Catheter With Movable Support Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rapid exchange balloon catheters face challenges in complex and costly construction, difficulty in machining thin internal wires, and increased risk of kinking when traversing tortuous pathways due to direct contact and attachment of internal wires with the outer catheter shaft.
Innovation Solution
A balloon catheter design featuring a support assembly with a first member and a second member, where the leading end of the second member is free of direct physical attachment to the first member, allowing transverse movement and minimizing kinking, while effectively transferring pushing forces through an internal shoulder within the catheter shaft.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If an internal wire is directly attached to the outer catheter shaft to enhance pushability and column strength, then the transmission of pushing force is improved, but the complexity of construction and assembly increases and manufacturing cost increases
Solution Approach 1:
The support assembly is divided into separate components: an internal wire and an outer catheter shaft with distinct features (internal shoulder, engagement features). This segmentation allows independent manufacturing of simpler components that are then assembled, reducing individual component complexity while maintaining overall structural integrity and pushability.
2Area of stationary object
If the internal wire is made thin to avoid obstructing the inflation lumen, then the inflation lumen size is preserved, but the difficulty of machining and grinding spatial features increases
Solution Approach 1:
The support structure is segmented into a thin internal wire and a separate outer shaft system. The wire can be made thin to preserve lumen area, while the outer shaft contains the complex geometric features (shoulders, engagement surfaces) that are easier to manufacture separately and assemble.
Solution Approach 2:
The outer catheter shaft acts as an intermediary structure that provides the complex geometric features needed for force transmission, allowing the internal wire to remain simple and thin. The intermediary shaft mediates between the simple wire and the requirement for complex force transmission geometry.
3Force
If the internal wire is directly attached to the outer catheter shaft to transmit pushing force, then the pushability is enhanced, but the risk of kink formation increases when traversing tortuous pathways
Solution Approach 1:
The connection between the internal wire and outer shaft is made dynamic rather than rigid. The wire can slide or articulate within the outer shaft structure, allowing it to adapt to tortuous pathways without kinking, while still effectively transmitting pushing forces when needed through engagement features like the internal shoulder.
Solution Approach 2:
The mechanical parameters of the wire-shaft interface are changed from fixed/rigid to movable/slidable. This parameter change allows the system to maintain force transmission capability while adapting to varying geometric conditions in tortuous pathways, preventing kink formation.
4Force
If a complex internal wire structure is used to improve force transmission, then the pushability is enhanced, but the manufacturing cost increases
Solution Approach 1:
The force transmission function is segmented between a simple internal wire and a separately manufactured outer shaft with engagement features. This allows each component to be manufactured using simpler, more cost-effective processes, while the assembled system achieves the required force transmission performance.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A balloon catheter including a catheter shaft (30), a balloon (36) and a support assembly (34). The catheter shaft defines an internal shoulder (80) and carries the balloon. The support assembly includes a first member (120) and a second member (122). The second member defines opposing, leading (152) and trailing (150) ends, and is arranged over the first member such that the leading end is distal the trailing end. The leading end is free of direct physical attachment to the first member. A portion of the first member (120) extends within a transition lumen (100) of the catheter shaft and the leading end bears against the internal shoulder such that when a pushing force is applied at a proximal region of the catheter shaft, it is transferred onto the internal shoulder via the support assembly. Furthermore, due to the leading end being free of direct physical attachement to the first member, the leading end of the second member is transversely movable relative to the first member, thereby minimizing possible kinking of the first member. The support assembly is simple an inexpensive.