Feasibility Study for Fatigue Detection of an Electrical Circuit Integrated into a Stent

Active Stents describe an approach of equipping stents with an electrical system for real time monitoring of physiological parameters in the body. This advancement is necessary since there are still medical concerns and drawbacks after stent implantation. Understanding the behavior of the integrated circuit, the interaction with the stent, and potential failure modes in simulated environments is essential to obtain a robust and reliable assembly. Other than existing approaches to integrate an electrical circuit into a stent, a miniaturized, polyimide-based, conformable electrical circuit is manufactured to meet the harsh environment within a blood vessel's prevailing cyclic mechanical loads. To detect different stages of mechanical fatigue of circuit tracks, a custom-made setup was created for measuring electrical voltage in the range of millivolts. First experiments with manually integrated simplified electrical circuits into a stent, show the longevity of different test cohorts/samples and no change of electrical performance up to 180 min without external load. Fatigue detection derived by different factors based on the complexity of the manufacturing and assembly procedure, excluding additional load, was possible with the here presented feasibility study.