Variable-Rigidity Delivery Tube Across the Aortic Arch

Solution Overview

Problem

Current ventricular assist devices face challenges in efficiently navigating the aortic valve and arch due to rigid delivery tubes, which can lead to complications during implantation and operation, and there is a need for a solution that allows for varying mechanical properties along the tube length to facilitate smooth passage and optimal blood pumping.

Innovation Solution

A left-ventricular assist device with a delivery tube that has varying flexural rigidity along its length, specifically designed to traverse the aortic valve, arch, and descending aorta, using a combination of materials and structures such as polyurethane, polyether block amide, and aramid fibers to ensure flexibility and tensile strength, along with a drive cable system to rotate the impeller for blood pumping.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a rigid delivery tube is used, then the delivery tube maintains structural strength, but it causes complications during navigation through the aortic valve and arch

Engineering Contradiction:

Improvestructural strengthVSAvoidnavigation through aortic structures

Core Design Contradiction:

StrengthVSEase of operation

Solution Approach 1:

The delivery tube incorporates different material properties at different locations: the first portion (distal end) has lower flexural rigidity to navigate the aortic valve and arch, while the second portion (proximal end) has higher flexural rigidity to maintain structural strength during implantation and operation. This spatial variation in material properties resolves the contradiction between navigability and structural integrity.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The delivery tube transitions from a static, uniform rigidity design to a dynamic, variable rigidity design where the flexural properties change along the length of the tube. This allows the tube to adapt its mechanical behavior to different operational phases: flexible during navigation, rigid during implantation and operation.

Inventive Principle:

Principle #15Dynamics

2Ease of operation

If the delivery tube is made flexible to navigate aortic structures, then navigation is improved, but the tube loses tensile strength

Engineering Contradiction:

Improvenavigation through aortic structuresVSAvoidtensile strength

Core Design Contradiction:

Ease of operationVSStrength

Solution Approach 1:

The delivery tube incorporates different material properties at different locations: the first portion (distal end) has lower flexural rigidity to navigate the aortic valve and arch, while the second portion (proximal end) has higher flexural rigidity to maintain structural strength during implantation and operation. This spatial variation in material properties resolves the contradiction between navigability and structural integrity.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The delivery tube uses composite material construction with varying compositions along its length. The first portion uses materials with lower flexural rigidity (such as polyurethane or polyether block amide) for navigation, while the second portion uses materials with higher flexural rigidity to maintain tensile strength. This composite approach allows both flexibility for navigation and strength for structural support.

Inventive Principle:

Principle #40Composite materials

3Ease of manufacture

If a uniform delivery tube design is used, then manufacturing is simplified, but it cannot optimize performance across different aortic structures

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidperformance optimization across aortic structures

Core Design Contradiction:

Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The delivery tube incorporates different material properties at different locations: the first portion (distal end) has lower flexural rigidity to navigate the aortic valve and arch, while the second portion (proximal end) has higher flexural rigidity to maintain structural strength during implantation and operation. This spatial variation in material properties resolves the contradiction between navigability and structural integrity.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The delivery tube is divided into distinct segments: a first portion (distal end) and a second portion (proximal end), each with optimized material properties for their specific functional requirements. This segmentation allows each portion to be independently optimized for its role while maintaining overall tube functionality.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS20240277990A1Delivery tube

Publication Date: 2024.08.22 MAGENTA MEDICAL LTD

AI summary

Apparatus and methods are provided, including a left-ventricular assist device that includes an impeller configured for insertion into a subject's left ventricle. A delivery tube passes through the subject's aorta, from outside the subject into the left ventricle. The delivery tube includes an outer layer that varies along a length of the delivery tube such that a flexural rigidity of the delivery tube at a first portion of the delivery tube, which is configured to traverse the aortic valve, is less than the flexural rigidity at a second portion, which is configured to traverse at least a portion of the aortic arch, and the flexural rigidity at the second portion is less than the flexural rigidity at a third portion, which is configured to traverse the descending aorta. Other applications are also described.