Square Leaflet Stitch for Prosthetic Heart Valve Sealing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing prosthetic heart valves face challenges in minimizing stenosis and regurgitation, and maintaining functionality over the patient's lifetime, with current designs often requiring anticoagulant therapy and having issues with valve leakage and restricted profiles during implantation.

Innovation Solution

A prosthetic heart valve design featuring a square stitch pattern between leaflets, secured to an expandable braided stent with a tubular seal, which provides a secure seal while minimizing apertures and profile width, using a single continuous thread with loops and segments to compress and support the leaflets, and a tubular seal attached to the braided stent for enhanced stability and reduced leakage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional stitching methods are used to connect leaflets, then the valve structure is simple to manufacture, but the seal between leaflets is insufficient leading to leakage

Engineering Contradiction:
Improveseal between leafletsVSAvoidstitch structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The square stitch is pre-formed with loops and segments designed to compress leaflet edges together before the valve is fully implanted. The stitch structure is prepared in advance with specific geometric configurations that will automatically provide compression and sealing when deployed, eliminating the need for complex post-implantation adjustments.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The square stitch incorporates curved segments between apertures that allow the stitch to flex and conform to the curved surfaces of the leaflet edges. This curvature enables the stitch to maintain consistent compression force around the entire leaflet perimeter, improving seal reliability while keeping the overall structure relatively simple.

Inventive Principle:
Principle #14Spheroidality (Curvature)

2Strength

If multiple apertures are created in leaflets for stitching, then the stitch can secure leaflets together, but the number of apertures increases leading to potential leakage paths and weakened leaflet structure

Engineering Contradiction:
Improveleaflet structural integrityVSAvoidseal between leaflets
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

Multiple stitch functions are merged into a single continuous thread structure. The square stitch uses one continuous thread that forms both securing loops and compressing segments, eliminating the need for multiple separate sutures or fasteners. This reduces the number of discrete apertures needed while maintaining secure leaflet connection and sealing.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The square stitch employs a continuous thread running through multiple apertures with loops and segments that continuously compress the leaflet edges together. This continuous compression action along the entire stitch path maintains seal reliability while the thread continuity distributes stress evenly, preserving leaflet structural integrity.

Inventive Principle:
Principle #20Continuity of useful action

3Ease of operation

If the prosthetic valve is designed with a larger profile for easier implantation, then the ease of operation improves, but the unexpanded profile increases making delivery through catheters more difficult

Engineering Contradiction:
Improveimplantation processVSAvoidunexpanded profile
Core Design Contradiction:
Ease of operationVSLength of moving object

Solution Approach 1:

The prosthetic valve is designed with dynamic characteristics, allowing it to transition between a compressed low-profile state for delivery through catheters and an expanded functional state for implantation. The square stitch and leaflet structure are engineered to maintain stability in both configurations, enabling easy delivery while ensuring proper function after deployment.

Inventive Principle:
Principle #15Dynamics

4Duration of action of stationary object

If mechanical heart valves are used, then the valve durability is high, but the patient must undergo anticoagulant therapy which has side effects

Engineering Contradiction:
Improvevalve functionalityVSAvoidanticoagulant therapy requirements
Core Design Contradiction:
Duration of action of stationary objectVSObject-affected harmful factors

Solution Approach 1:

The invention changes the material parameter of the valve from synthetic mechanical materials to biologic tissue materials. This parameter change allows the valve to function durably without requiring anticoagulant therapy, as the biologic tissue is more compatible with the body's natural clotting mechanisms while maintaining sufficient durability for long-term function.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP3250154B1Prosthetic heart valve square leaflet-leaflet stitch
Publication Date: 2024.05.15 BOSTON SCIENTIFIC SCIMED INC
  • EP3250154B1 patent drawingFigure 1A
  • EP3250154B1 patent drawingFigure 1B
  • EP3250154B1 patent drawingFigure 1C~1H

AI summary

A prosthetic heart valve provided herein can include at least two leaflets being secured together along aligned edges thereof by a stitch of a single thread. The stitch includes at least one loop extending through a first aperture, around the aligned edges, and back through the first aperture.