Impact of stent use on vasospasm occurrence after subarachnoid hemorrhage: a propensity score matching analysis

Objective We hypothesized that stents in stent-assisted coil embolization during endovascular treatment (EVT) may reduce the risk of symptomatic vasospasm following aneurysmal subarachnoid hemorrhage (aSAH) and its treatment. This study aimed to evaluate the impact of stent placement on the occurrence of symptomatic vasospasm, identify the associated risk factors, and analyze symptomatic vasospasm occurrence according to treatment modality and aneurysm location. Methods We retrospectively analyzed 546 aSAH patients treated from 2013 to 2022. The primary outcome was symptomatic vasospasm occurrence. Potential risk factors for symptomatic vasospasm were evaluated using multivariate logistic regression. Propensity score matching was used to assess the impact of stent use during EVT, treatment modality (coiling vs clipping), and aneurysm location (anterior vs posterior circulation) on symptomatic vasospasm occurrence. Results Multivariate analysis identified younger age (OR 0.954, 95% CI 0.934 to 0.974, P<0.001), external ventricular drainage (EVD) placement (OR 2.470, 95% CI 1.404 to 4.346, P=0.002), higher white blood cell (WBC) count (OR 1.057, 95% CI 1.006 to 1.109, P=0.027), and higher modified Fisher scale score (OR 4.303, 95% CI 1.725 to 10.736, P=0.002) as significant risk factors. Propensity score matched analysis revealed that stent use during EVT significantly reduced the risk of symptomatic vasospasm (OR 0.413, 95% CI 0.176 to 0.970, P=0.042); however, treatment modality and aneurysm location showed no significant influence. Conclusions We found that stent placement during EVT significantly reduced the occurrence of symptomatic vasospasm after aSAH. Additional risk factors included younger age, EVD placement, higher WBC count, and higher modified Fisher scale score. Further studies are warranted to validate these findings and explore their implications for clinical practice.