Fig. 4: Fabrication, integration, deployment, and functional validation of the smart stent system.

a Two-dimensional design of the hybrid polymer stent incorporating PLA curve rings and PCL connectors. b Optical image of the 3D-printed stent fabricated from PCL/PLA hybrid material. c Radial force comparison of stents composed of pure PCL, pure PLA, and hybrid PCL/PLA, demonstrating enhanced mechanical strength of the hybrid structure. d Optical images of the wireless pressure sensor and stent prior to and following integration using a PVA-based coupling layer. e Stepwise catheter-based delivery process showing crimping, expansion, and vascular apposition of the smart stent. f Deployment of the integrated device into a 3 mm-diameter coronary artery phantom, confirming compatibility with standard balloon-catheter procedures. g Resonance frequency response recorded under varying hydrostatic pressures, simulating physiological hemodynamic conditions. h, i Extraction of resonance frequency minima and curve fitting, highlighting pressure-dependent frequency shifts. j Correlation between applied pressure and resonance frequency derived from fitted data. k Linear regression analysis confirming strong agreement between applied pressure and frequency response. l Comparison of predicted versus measured pressure values, validating the reliability of the smart stent for real-time intravascular pressure monitoring