Stent With Sinusoidal Struts and Segmented Joints

Solution Overview

Problem

Current stents face challenges in maintaining vessel patency while providing sufficient flexibility and resistance to fatigue fracture, especially in tortuous vasculature, where they are subjected to torsion, bending, and compression, leading to potential jagged breakage and compromised support.

Innovation Solution

A stent design featuring a plurality of annular segments with temporary non-permanent joints and shape memory materials, allowing for controlled fracture at predetermined locations to prevent fatigue fractures, maintaining radial strength and flexibility for deployment in curved vessels.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the stent is made rigid to maintain vessel patency, then radial strength is improved, but flexibility and resistance to fatigue fracture deteriorate

Engineering Contradiction:

Improveradial strengthVSAvoidresistance to fatigue fracture

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The stent is divided into multiple articulated segments connected by joints, allowing each segment to maintain structural integrity while the overall structure remains flexible. The joints between segments enable controlled movement to accommodate vessel curvature and physiological stresses, preventing catastrophic failure while maintaining radial support.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The stent incorporates dynamic joints that allow controlled movement between segments in response to physiological stresses. These joints enable the stent to adapt to vessel curvature and bending forces, transforming from a static rigid structure to a dynamic system that can absorb and distribute mechanical stresses, thereby improving fatigue resistance.

Inventive Principle:

Principle #15Dynamics

2Ease of operation

If the stent is made flexible to facilitate deployment in tortuous vasculature, then ease of operation is improved, but radial strength and vessel support deteriorate

Engineering Contradiction:

Improveease of deploymentVSAvoidradial strength

Core Design Contradiction:

Ease of operationVSStrength

Solution Approach 1:

The stent is divided into multiple articulated segments connected by joints, allowing each segment to maintain structural integrity while the overall structure remains flexible. The joints between segments enable controlled movement to accommodate vessel curvature and physiological stresses, preventing catastrophic failure while maintaining radial support.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different parts of the stent have different mechanical properties - the segments provide radial strength while the joints provide flexibility. This local differentiation of mechanical properties allows the stent to simultaneously achieve the rigidity needed for vessel support and the flexibility needed for easy deployment in tortuous vasculature.

Inventive Principle:

Principle #3Local quality

3Stability of the object's composition

If the stent is made as a single continuous structure, then structural integrity is improved, but controlled fracture and modular separation deteriorate

Engineering Contradiction:

Improvestructural integrityVSAvoidcontrolled fracture capability

Core Design Contradiction:

Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The stent is divided into multiple articulated segments connected by joints, allowing each segment to maintain structural integrity while the overall structure remains flexible. The joints between segments enable controlled movement to accommodate vessel curvature and physiological stresses, preventing catastrophic failure while maintaining radial support.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The stent incorporates predetermined fracture points and articulated joints that are designed to fail in a controlled manner under excessive stress. This preliminary design of failure points allows the stent to separate into smaller modular sections rather than fracturing catastrophically, maintaining structural integrity during normal operation while enabling controlled separation when needed.

Inventive Principle:

Principle #10Preliminary action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The stent design enhances resistance to fatigue fractures, ensuring controlled separation that does not compromise vessel support, while maintaining flexibility and radial strength, facilitating easy deployment and accommodation of physiological stresses.

Implementation Method 1

The stent may be self-expanding or balloon-expandable

Methodology Applied

Scientific EffectShape memory: Shape Memory Alloy

Data Source

PatentUS9603732B2Stent including sinusoidal struts

Publication Date: 2017.03.28 COVIDIEN LP

AI summary

The invention provides for intra-luminal stents, especially stent having controlled fracture connection, as well as, methods of making and using the same. In one embodiment, a stent for implantation into a vessel has a plurality of annular segments collectively forming tubular shape, characterized by at least first and second adjacent annular segments each defined by a plurality of struts and at least one joint interconnecting respective struts of the first and second segments on a non-permanent basis.