Stent Pump with Deployable Stream Former for Reduced Hemolysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cardiac assist devices require major surgical intervention and can cause hemolysis due to turbulent blood flow and abrupt velocity changes, necessitating a solution for improved blood flow and reduced invasiveness.
Innovation Solution
A stent pump with a deployable impeller and stream former arrangement that unfolds radially for increased pumping capacity, allowing for low rotational speed and reduced blood trauma, and is deployable via transcatheter intervention without sternotomy, using a steerable guiding wire and shape-memory alloys for deployment and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional pump systems are used to assist cardiac output, then pumping capacity is improved, but hemolysis and blood cell damage increase due to turbulent flow and abrupt velocity changes
Solution Approach 1:
The pump system employs a flexible, collapsible housing that can dynamically adjust its configuration between a compressed delivery state and an expanded operational state. This dynamic structure allows the pump to achieve optimal blood flow characteristics in the expanded state while enabling minimally invasive delivery in the compressed state, resolving the contradiction between pumping capacity and blood cell damage by optimizing the operational geometry to reduce turbulence.
Solution Approach 2:
The invention changes the physical parameters of the pump housing from a rigid fixed structure to a flexible variable structure that can alter its geometric parameters (diameter, volume, flow path) between delivery and operational states. This parameter change enables the pump to provide adequate pumping capacity when expanded while minimizing blood trauma through optimized flow characteristics, and facilitates transcatheter delivery when compressed.
2Productivity
If conventional pump systems are implanted to assist cardiac output, then hemodynamic performance is improved, but surgical intervention and invasiveness increase
Solution Approach 1:
The pump housing is designed as a dynamic structure that transitions from a compressed configuration for minimally invasive catheter delivery to an expanded configuration for optimal hemodynamic performance. This dynamic capability allows the pump to achieve adequate pumping function through a smaller, less invasive delivery approach, eliminating the need for major surgical intervention while maintaining effective cardiac output assistance.
Solution Approach 2:
The pump components are arranged in a nested configuration where the impeller and stream former are contained within a collapsible housing that can be compressed for delivery and expanded for operation. This nesting approach enables the pump to be delivered through catheters via minimally invasive routes while providing sufficient pumping capacity when deployed, thus improving ease of operation without sacrificing hemodynamic performance.
3Stability of the object's composition
If the pump housing is made rigid and fixed for stable operation, then structural stability is improved, but deliverability through catheters and minimally invasive routes is worsened
Solution Approach 1:
The housing transitions from a rigid fixed structure to a flexible dynamic structure that can collapse for catheter delivery and expand for stable operation. This dynamic behavior allows the pump to achieve both structural stability during operation (when expanded) and deliverability during insertion (when compressed), resolving the contradiction between stability and ease of operation.
Solution Approach 2:
The housing is constructed from flexible materials that can deform between compressed and expanded states. This flexible shell structure provides structural stability when expanded for operation while enabling compression for minimally invasive delivery through catheters, thus simultaneously satisfying the requirements for stability and deliverability that a rigid structure cannot meet.
4Productivity
If the impeller diameter is increased for higher pumping capacity, then productivity is improved, but the risk of blood trauma and hemolysis increases due to higher rotational speeds
Solution Approach 1:
The pump system dynamically adjusts its operational parameters by transitioning between compressed and expanded states, allowing optimal blood flow characteristics to be achieved in the expanded state with reduced rotational speeds. This dynamic configuration enables adequate pumping capacity without the blood trauma associated with high-speed rotation, as the expanded geometry provides smoother flow paths and reduced turbulence.
Solution Approach 2:
The invention changes the geometric parameters of the pump housing from a compressed delivery configuration to an expanded operational configuration, which alters the flow dynamics and allows for lower rotational speeds to achieve the same pumping capacity. This parameter change reduces blood trauma and hemolysis by optimizing the flow characteristics at reduced speeds while maintaining productivity.
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 pump achieves optimal blood flow and reduced cell damage with minimal invasiveness, maintaining hemodynamic performance and allowing for pulsatile or continuous flow control, enhancing cardiac output and reducing the risk of hemolysis.
Implementation Method 1
A typical pump uses an impeller or a set of blades, which spins to push a flow of fluid in one direction.
Implementation Method 2
the stream former is arranged downstream of the impeller... the blood flows due to suction into the housing as well as when the blood leaves the pump
Implementation Method 3
the housing, the stream former and/or the impeller are deployable from a first position, in which the housing, the stream former and/or the impeller are folded for being arranged within a delivery device, into a second, expanded position
Data Source
AI summary
The invention relates to a stent pump for intravascular, intraventricular or intraatrial placement inside the human heart comprising: —a preferably tubular housing having an inlet and an outlet, —an impeller, and —a stream former, wherein the impeller and optionally the stream former are arranged within the housing, characterized in that the stream former is arranged downstream of the impeller, and the housing, the stream former and/or the impeller are deployable from a first position, in which the housing, the stream former and/or the impeller are folded for being arranged within a delivery device, into a second, expanded position, in which the housing, the stream former and/or the impeller are deployed.