Fistula Join System for Arteriovenous Anastomosis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hemodialysis vascular access dysfunction in patients with end-stage renal disease is caused by maturation failure and early venous stenosis due to neointimal hyperplasia, primarily driven by hemodynamic stress and high wall tension at the arteriovenous fistula, leading to reduced blood flow and increased morbidity.
Innovation Solution
A fistula join system comprising a coupler and a restrictor sleeve that configures the blood vessels at the fistula to achieve a desired acute angle and shape, constraining the vein to reduce wall tension and promote laminar blood flow, thereby mitigating stenosis and improving vascular access.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a fistula is created to enable hemodialysis vascular access, then blood flow from artery to vein is established, but hemodynamic stress and high wall tension cause neointimalhyperplasia leading to venous stenosis and maturation failure
Solution Approach 1:
The device applies preliminary counteracting forces to the vein wall at the anastomosis site to counterbalance the hemodynamic stress and wall tension that would otherwise cause neointimalhyperplasia. By pre-applying this counter-action, the device prevents the pathological thickening before it occurs, thereby maintaining vascular access durability while preserving blood flow.
Solution Approach 2:
The device converts the harmful hemodynamic stress and wall tension into a beneficial controlled compression force. By harnessing the same forces that cause stenosis and transforming them into a therapeutic compression, the device promotes vein maturation and prevents neointimalhyperplasia, turning the pathological process into a protective mechanism.
2Force
If the vein wall thickens to adapt to high pressure, then wall tension is reduced, but this compensatory reaction initiates intimalhyperplasia and vein stenosis
Solution Approach 1:
The device applies preliminary counteracting forces to the vein wall at the anastomosis site to counterbalance the hemodynamic stress and wall tension that would otherwise cause neointimalhyperplasia. By pre-applying this counter-action, the device prevents the pathological thickening before it occurs, thereby maintaining vascular access durability while preserving blood flow.
3Ease of manufacture
If the vein is left unconfigured, then the procedure is simple, but turbulent flow and low shear stress regions develop causing stenosis
Solution Approach 1:
The device is pre-configured with a specific geometry designed to optimize blood flow characteristics at the anastomosis site. By incorporating the flow-directing structure into the device itself, the beneficial flow configuration is achieved without requiring complex surgical manipulation, thus maintaining procedural simplicity while eliminating turbulent flow and low shear stress regions.
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 system enhances blood flow through the fistula by reducing turbulent flow and increasing hemodynamic shear stress, thereby preventing or treating intimal hyperplasia and stenosis, and maintaining effective vascular access for hemodialysis.
Implementation Method 1
promote laminar blood flow
Implementation Method 2
increasing hemodynamic shear stress
Data Source
AI summary
An embodiment of the invention relates to a method of configuring blood vessels at an anastomosis, the method comprising: ensheathing a segment of a transected first blood vessel in a lumen of a sleeve so that an open end of the segment protrudes from a sleeve end; suturing edges of an incision made in a second blood vessel to the open end of the first blood vessel to create an anastomosis; and sliding the sleeve along the first blood vessel to position the sleeve at the anastomosis.