Implantable Membrane Sensors and Long-Range Wireless Electronics for Continuous Monitoring of Stent Edge Restenosis

Abstract

Continuous monitoring of vascular stent health is crucial for high-risk patients. Current approaches predominantly rely on inductive coupling, which limits the wireless reading distance and requires precise antenna alignment with implanted stents. Here, we present a long-range wireless electronic system that incorporates a low-resistance inductive stent fabricated via laser micromachining and electroplating of biocompatible metal films, forming a mechanically robust and conductive interface optimized for radar interrogation. A conformal, flexible capacitive pressure sensor is developed from soft dielectric elastomers and integrated within the stent's structure, enabling localized detection of hemodynamic pressure changes indicative of stent-edge restenosis. Computational modeling validates the antenna design as an effective radiator, while an in vitro study evaluates the performance of the stent-sensor assembly and wireless coupling. Our system successfully detected the stent from a distance of 50 cm, providing trackable localized pressure signals at 2 GHz for healthy stents as well as diagnostic capabilities for 50% stent-edge restenosis. This work establishes a new class of enhanced wireless stents, offering extended readout distances and real-time diagnostic capability, with broad implications for developing next-generation bioelectronic interfaces.