SPIE proceeding.pdf

A leading cause of death in the US is cardiovascular disease, of which approximately 44% are attributable to coronary artery disease. A minimally invasive procedure with stent placement has drastically improved the outcomes. However, there are still relatively high percentages of a life-threatening complication called "restenosis" (i.e., re-narrowing of a coronary artery). Here, we introduce an imperceptible nanostructured electronic stent that incorporates an ultrathin stretchable wireless sensor with a stent for continuous surveillance of restenosis along with neointimal proliferation and plaque deposition. The low-profile, nanomembrane capacitive strain sensor is constructed by the printing of conductive nanoparticles and polymers on a soft elastomeric membrane. This sensor is capable of detecting strains as low as 0.15% with a sensitivity of 3% per linear strain. The sensor performance is suitable to detect small alterations produced in the coronary artery with the progression of restenosis under typical pulsatile flow. In addition, an in vitro testing platform has been developed to accurately evaluate the sensor's performance. Both numerical analysis and computational fluid dynamics (CFD) were used to design the artery model with various levels of restenosis. The strain plots of artery models from both numerical and computational analyses have successfully shown the relationship between the strain and restenosis levels, varied pressures, artery lumens, and artery thicknesses. Our recent outcomes will provide better solutions for both diagnostic heart disease and many other vascular diseases that require stents.