Effect of Angiographic Hemodynamic Parameters and Vascular Tortuosity on In-Stent Restenosis in Intracranial Atherosclerosis

BACKGROUND AND OBJECTIVE: In-stent restenosis (ISR) is an important factor affecting the long-term efficacy of stenting for intracranial atherosclerotic stenosis (ICAS). We aimed to investigate the risk factors of ISR by analyzing the clinical features, angiography-based hemodynamic parameters, and vascular morphology. METHODS: Patients with severe symptomatic ICAS undergoing stenting were retrospectively screened. The vascular morphology was described by angle, relative length (RL), triangulation index (TI). Hemodynamic parameters were assessed by quantitative digital subtraction angiography. Four regions of interest (ROIs) were delineated near the lesion. Relative time to peak (rTTP) was the difference in TTP between ROIs. Logistic regression was performed to explore the risk factors of ISR. RESULTS: Of the 312 patients, 106 (median IQR age, 61.0 53.8-66.3 years; 83 78.3% male) were ultimately included, of whom 22 patients (20.8%) developed ISR, with a median follow-up time of 6.6 (6.1-8.8) months. Multivariate logistic analysis showed that residual stenosis (adjusted OR = 1.107, p = 0.007), monocyte to high-density lipoprotein cholesterol ratio (MHR) (adjusted OR = 1.031, p = 0.032), hyperglycemia (adjusted OR = 5.695, p = 0.015), post-stenting RL (adjusted OR = 0.802, p = 0.032) and trans-stenotic rTTP CONCLUSIONS: Angiographic hemodynamic parameters, vascular tortuosity, and MHR are significant risk indicators associated with ISR. The developed model shows strong potential for identifying high-risk patients.