Subintimal Re-entry Catheter with Deflection Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for recanalizing occluded blood vessels, particularly in cases of chronic total occlusion, face challenges in re-entering the true lumen from the subintimal space, leading to difficulties in restoring blood flow.
Innovation Solution
A subintimal recanalization catheter with a distal portion having flattened wings and a guide wire lumen, along with a deflection mechanism, is used to orient and deflect the catheter tip towards the true lumen, facilitating re-entry by actuating a pull wire to curve the distal nose and guide wire port for successful re-canalization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a subintimal pathway is created around the occlusion, then recanalization can be achieved when antegrade penetration fails, but re-entering the true lumen from the subintimal space becomes difficult
Solution Approach 1:
The catheter is pre-formed with a flattened distal portion and wings that are configured to engage the vessel wall before re-entry occurs. This preliminary configuration enables the operator to easily orient and anchor the catheter against the vessel wall, facilitating successful re-entry into the true lumen without requiring complex manipulation during the critical re-entry moment
Solution Approach 2:
The deflection wire mechanism enables dynamic curvature change in the catheter's distal portion. By actuating the deflection wire, the distal portion can be curved to orient the guide wire port toward the true lumen, creating an optimal re-entry angle and significantly improving the ease of re-entry operation
2Ease of manufacture
If the catheter maintains a simple tubular structure, then manufacturing is easier, but orientation and control within the subintimal space becomes difficult
Solution Approach 1:
The catheter is divided into distinct functional segments: a proximal tubular portion for navigation, a flattened distal portion with wings for anchoring and orientation, and a deflection wire mechanism for angular control. This segmentation allows each portion to be optimized for its specific function while maintaining overall manufacturing feasibility through modular construction
Solution Approach 2:
The distal portion of the catheter is intentionally made asymmetric with a flattened cross-section and extended wings rather than a symmetric circular tube. This asymmetric design provides inherent orientation cues and mechanical engagement features that greatly improve the ease of orienting the catheter within the subintimal space, while the asymmetric shape can still be manufactured using standard forming techniques
3Ease of operation
If the distal portion is made flattened with wings, then orientation within subintimal space is facilitated, but device complexity increases
Solution Approach 1:
Multiple functions are merged into the distal portion structure: the flattened shape provides orientation, the extended wings provide anchoring and directional control, and the integrated deflection wire mechanism provides angular adjustment. By combining these functions into a single integrated distal component rather than separate attachments, the overall device complexity is minimized while maintaining enhanced operational capabilities
Data Source
Figure 1A~1B
Figure 1C
Figure 2
AI summary
A subintimal recanalization catheter, including an elongate shaft including a first tubular member and a penetration member slidably disposed in a lumen of the first tubular member. The penetration member includes a distal tip positioned proximal of a distal nose of the first tubular member. The distal nose of the first tubular member includes a ramp and a guide wire lumen extending through the distal nose of the first tubular member. Longitudinal movement of the penetration member relative to the first tubular member causes the penetration member to contact the ramp to direct the distal tip of the penetration member away from the first tubular member.