Prosthetic Heart Valve Leaflets with Sliding Suture Loops
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing prosthetic heart valves face issues with stress concentrations and abrasion of suture loops due to changes in frame diameter and systole-diastole cycles, leading to potential damage and reduced durability.
Innovation Solution
The attachment of scalloped edges of valvular leaflets to struts via suture loops oriented perpendicular to the scalloped edges, allowing sliding movement along strut segments, and the use of flexible or rigid scallop line elements to manage stress and prevent abrasion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the frame diameter changes during crimping procedure, then the prosthetic valve can be deployed, but stress concentrations and abrasion occur at suture loops
Solution Approach 1:
A PTFE reinforcement strip is introduced as an intermediary element between the suture loop and the leaflet/scallop line. This reinforcement strip distributes the stress away from the suture loop, preventing abrasion and stress concentrations during frame diameter changes in the crimping procedure while allowing the valve to be deployed
2Strength
If suture loops attach leaflets to struts, then the valvular structure is secured, but abrasion occurs during systole and diastole cycles
Solution Approach 1:
The PTFE reinforcement strip serves as a mediator between the suture loop and the leaflet attachment region. It distributes mechanical stresses and prevents direct abrasion between the suture loop and the scallop line during systole and diastole cycles, while maintaining secure attachment of the valvular structure
Solution Approach 2:
The reinforcement strip changes the mechanical parameters at the attachment region by distributing stress over a larger area and altering the friction characteristics through PTFE material properties, thereby reducing abrasion during cardiac cycles
Data Source
Figure 1
Figure 2A~2B
Figure 3A~3B
AI summary
Disclosed are techniques for construction of prosthetic heart valves, particularly techniques for attachment of scalloped edges of valvular leaflets to struts of mechanical frames using sutures and/or other materials as intermediate coupling members. In some embodiments, the scalloped edges of the leaflets are coupled to the segments of the struts of the frame via suture loops that are oriented transverse to the scalloped edges of the leaflets. In some embodiments, central portions of scallop line segments are attached to the scalloped edges of the leaflets and are not attached to the frame. In some embodiments, strut segments are tapered to limit translation of suture loops. In some embodiments, a cloth strip couples the scalloped edges of the leaflets to frame struts. In some embodiments, the scalloped edge is attached to adjacent segments of intersecting struts via sliding suture loops, where the adjacent segments join at a common pivot joint.