Stent Graft Coverage Layout for Fenestration and Axial Support

Solution Overview

Problem

Existing stent grafts face challenges in achieving optimal fenestration size and edge support, particularly in complex anatomical structures like the aortic arch, leading to potential separation of branch stents and reduced adaptability.

Innovation Solution

The stent graft design incorporates regions with varying coverage rates of wavy rings, including a region A with lower coverage for fenestration and region B with higher coverage for axial support, along with keel regions to enhance stability and prevent shortening.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the stent graft uses uniform high coverage rate of wavy rings throughout, then axial support is improved, but fenestration capability and adaptability to branch vessels deteriorate

Engineering Contradiction:

Improveaxial supportVSAvoidfenestration capability

Core Design Contradiction:

StrengthVSAdaptability or versatility

Solution Approach 1:

The stent graft applies different coverage rates of wavy rings in different circumferential regions. Specifically, the first region has a first coverage rate optimized for axial support, while the second region has a second coverage rate optimized for fenestration. This local differentiation allows each region to perform its specific function effectively without compromising the other.

Inventive Principle:

Principle #3Local quality

2Adaptability or versatility

If the stent graft uses uniform low coverage rate of wavy rings throughout, then fenestration capability is improved, but axial support and prevention of retraction deteriorate

Engineering Contradiction:

Improvefenestration capabilityVSAvoidaxial support

Core Design Contradiction:

Adaptability or versatilityVSStrength

Solution Approach 1:

The stent graft applies different coverage rates of wavy rings in different circumferential regions. Specifically, the first region has a first coverage rate optimized for axial support, while the second region has a second coverage rate optimized for fenestration. This local differentiation allows each region to perform its specific function effectively without compromising the other.

Inventive Principle:

Principle #3Local quality

3Adaptability or versatility

If the window size is increased to meet branch vessel requirements, then adaptability is improved, but window edge support deteriorates

Engineering Contradiction:

Improvebranch vessel adaptabilityVSAvoidwindow edge support

Core Design Contradiction:

Adaptability or versatilityVSStrength

Solution Approach 1:

The stent graft applies different coverage rates of wavy rings in different circumferential regions. Specifically, the first region has a first coverage rate optimized for axial support, while the second region has a second coverage rate optimized for fenestration. This local differentiation allows each region to perform its specific function effectively without compromising the other.

Inventive Principle:

Principle #3Local quality

Data Source

PatentEP3733123B1Stent graft

Publication Date: 2025.11.05 LIFETECH SCI (SHENZHEN) CO LTD

Figure 1~2
Figure 3~4
Figure 5~6

AI summary

A stent graft; the stent graft is provided in the axial direction thereof with at least one Region T, and the Region T includes a plurality of wavy rings (101); in the circumferential direction, the Region T includes a region A and a Region B that is connected to the region A, the ratio of the area of the region A to the area of the Region T being 1/4-2/3, the ratio of the coverage rate of the wavy rings (101) in the region A to the coverage rate of the wavy rings (101) in the Region B being 1/5-9/10, and the ratio of the coverage rate of the wavy rings (101) within any circular region having a diameter of 20 mm within the region A to the coverage rate of the wavy rings (101) in the region A being 0.7-1.3.