Zig-Zag Expandable Sheath for Kink-Resistant Vessel Navigation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing expandable introducer sheaths for prosthetic devices are prone to kinking when passing through curved vasculature, requiring increased insertion force and posing a risk of trauma to the patient.
Innovation Solution
The introduction of a kink-resistant expandable sheath with a cylindrical frame formed by a plurality of struts arranged in a zig-zag configuration, which allows the sheath to expand from a first diameter to a second diameter upon passage of a medical device, minimizing kinking and reducing insertion force.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional expandable sheaths are used, then the sheath can be expanded to accommodate prosthetic devices, but the sheath is prone to kinking when passing through curved vasculature
Solution Approach 1:
The sheath incorporates a zig-zag configuration that allows controlled curving and bending without kinking. The alternating pattern of compressed and uncompressed portions enables the sheath to navigate curved vasculature while maintaining structural integrity and preventing kink formation.
Solution Approach 2:
The sheath transitions from a static rigid structure to a dynamic flexible structure that can adapt its shape. The expandable design with zig-zag configuration allows the sheath to dynamically adjust its curvature and flexibility to match the vasculature path, preventing kinks during navigation.
2Adaptability or versatility
If the sheath is expanded to accommodate larger prosthetic devices, then the device can be delivered, but increased insertion force is required
Solution Approach 1:
The sheath is divided into multiple segments or sections along its length, with alternating compressed and uncompressed portions in the zig-zag configuration. This segmentation allows progressive expansion and reduces the peak force required by distributing the expansion effort across multiple sections rather than requiring simultaneous expansion of the entire sheath.
Solution Approach 2:
The sheath utilizes changes in physical parameters including radial dimension (expansion from collapsed to expanded state) and structural configuration (zig-zag pattern). These parameter changes enable the sheath to accommodate larger devices while the alternating compressed/uncompressed portions facilitate gradual expansion that reduces insertion force requirements.
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Expandable sheaths are disclosed herein. In some aspects, the sheath comprises at least one plurality of struts arranged to form an expandable cylindrical frame such that the formed frame is kink resistant. The disclosed frames are configured to expand from a first diameter d1 in an unexpended position to a second diameter d2 an expanded position upon passage of a medical device, while maintaining the kink resistance. Also disclosed are methods of making the same.