Abstract
PURPOSE: In-stent restenosis (ISR) after vertebral artery stenting (VAS) affects 20-35% of patients, yet current risk stratification lacks sensitivity for early intervention. We propose the first combined biomarker model integrating endothelin-1 (ET-1) and fibroblast growth factor 23 (FGF23) to address this gap. METHODS: A prospective cohort study was conducted involving 148 patients who underwent VAS between 2020 and 2024. Blood samples were collected preoperatively to measure ET-1 and FGF23 levels. ISR was defined as a stenosis of at least 50% on follow-up imaging. Statistical analyses included multivariable logistic regression and receiver operating characteristic (ROC) curve evaluations to assess the biomarkers' performance. RESULTS: ISR occurred in 34 patients (23%). Both ET-1 and FGF23 levels were significantly higher in the ISR group. Multivariate analysis identified ET-1, FGF23, stent length, and LDL-C levels as independent predictors of ISR. The combined model using both biomarkers demonstrated superior discriminative performance (AUC = 0.96) compared to individual markers (AUC = 0.73 for ET-1 and AUC = 0.77 for FGF23). The model achieved sensitivity and specificity of 92.3% and 89.7%, respectively. CONCLUSION: The combined assessment of serum ET-1 and FGF23 exhibits a synergistic predictive role for ISR after VAS. The ET-1/FGF23 model enables personalized risk stratification, guiding targeted therapies to reduce recurrent ischemic events and healthcare costs.