Evaluating the performance of a configurable finite element model as a tool in composite catheter design

Abstract

Currently there are limited predictive modeling tools available for composite interventional catheter design. Most interventional catheter development involves iteration based design. Composite interventional catheters typically consist of a PTFE inner layer wrapped with a fine strand, metal reinforcement layer covered with a TPE (thermoplastic elastomer) outer layer. Fast reliable computational based techniques for early stage catheter design would limit the number of prototypes required to get to concept or design freeze stage therefore reducing development time. This paper’s goal is to examine how effective FEA is as a technique for predicting the performance of a composite catheter shaft. The steps taken and challenges overcome in creating a configurable FE model for a spirally reinforced composite catheter are outlined. The paper presents Finite Element (FE) generated data for tensile yield. This is a fundamental performance parameter in interventional catheter design. Catheters are designed to operate below their yield point. Models developed for simulating tensile yield can likely be adapted to simulate other performance characteristics such as flexural properties and torsion characteristics as part of future work. Data from FEA analysis is compared with data from physically testing catheters built to the same specification as that used in the FE model configuration.