Flexible Lead-free Piezoelectric Microcone Array for Direct Assessment of Vascular Stiffness

Measurement of vascular stiffness is crucial for evaluating arteriosclerosis severity and early warning of cardiovascular diseases. Current diagnostic techniques such as magnetic resonance elastography (MRE) and optical coherence tomography (OCT) fail to directly measure vascular mechanical properties, limiting early disease detection. Here, we propose a novel technology: a flexible lead-free piezoelectric microcone array integrated with a balloon catheter for real-time vascular stiffness assessment. The array uses microcone shaped barium titanate (BaTiO3) piezoelectric ceramics encapsulated in polydimethylsiloxane (PDMS), optimized via finite element method (FEM) for enhanced sensitivity. We validated the sensor’s performance through compression testing, in vitro vascular model experiments, and ex vivo vascular studies. Results demonstrate that the sensor, with a compact size (1.5 mm×2.6 mm×0.7mm) and compatibility with standard balloon catheters, enables accurate vascular mechanical characterization, showing great potential for clinical translation in early cardiovascular disease diagnosis.