Prosthesis Delivery Device Sheath Retraction Assist
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing delivery and deployment devices for endoluminal prostheses require high manual force, often exceeding 22.5 pounds, to retract the sheath due to high retraction resistance, which can tire operators and is undesirable.
Innovation Solution
A delivery and deployment device with a deployment assist mechanism, such as a spring or hydraulic system, that applies a retraction force to reduce the manual force required to retract the sheath over a retraction distance, potentially requiring no additional force in some cases, while maintaining operator control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If the delivery catheter, sheath, and prosthesis are tightly interconnected to provide a low-diameter profile, then the radial profile is reduced allowing atraumatic access, but the retraction force required to deploy the prosthesis increases to over 100 Newtons
Solution Approach 1:
A deployment assist mechanism is pre-loaded with stored energy (spring compression or hydraulic pressure) that is activated during deployment. This preliminary preparation of energy allows the system to overcome the high retraction resistance without requiring excessive manual force from the operator during the actual deployment moment.
Solution Approach 2:
The patent introduces a deployment assist mechanism as an intermediary element between the operator and the sheath-d delivery catheter system. This intermediary mechanism (spring or hydraulic cylinder) transfers and amplifies the operator's input force, enabling control of the high-force deployment process with minimal manual effort.
2Reliability
If high retraction force is required to deploy the prosthesis, then the prosthesis can be securely retained during delivery, but operator fatigue increases due to the high force requirement
Solution Approach 1:
The deployment assist mechanism is designed to be self-activating through stored energy (pre-compressed spring or pre-pressurized hydraulic system). Once triggered, the mechanism automatically generates the necessary retraction force without requiring continuous manual effort from the operator, thereby eliminating operator fatigue while maintaining secure prosthesis retention throughout the procedure.
Solution Approach 2:
The deployment process is divided into distinct phases: a triggering phase where the operator initiates deployment with minimal force, and an execution phase where the stored energy mechanism automatically provides the high retraction force needed. This periodic action allows the operator to avoid sustained high-force application, preventing fatigue.
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
Reduces the manual force needed to deploy the prosthesis, minimizing operator fatigue and maintaining control over the deployment process, with the assist mechanism ensuring the sheath retracts without additional input when the retraction force exceeds resistance.
Implementation Method 1
The assist mechanism may comprise a stored energy device, such as a spring. A spring may comprise, for example, one or more coil springs and/or one or more gas springs.
Implementation Method 2
The assist mechanism may comprise a hydraulic cylinder and/or a gas cylinder.
Data Source
AI summary
A device for delivering and deploying a prosthesis is described and comprises an elongate sheath having a sheath lumen and a delivery catheter slidably disposed within the sheath lumen. A deployment assist mechanism may be coupled to the delivery catheter and the sheath and configured to apply a retraction force to the delivery catheter and the sheath. Additional devices, systems, and methods of delivering and deploying a prosthesis are described.