Stent Angioplasty for the Treatment of Cerebral Vasospasm: A Systematic Review and Meta-Analysis

Several case series and prospective cohorts have reported the use of stent retrievers (SR) and specifically designed expanding stents (ES) to perform in situ mechanical stent angioplasty to treat cerebral vasospasm in subarachnoid vasospasm. The aim of this study was to review and conduct a meta-analysis to evaluate the safety and efficacy of this novel technique. A systematic review and meta-analysis was conducted according to established protocols. Searches were conducted in PubMed, Scopus, Web of Science, and EMBASE databases up to June 2024, including variations of "stent," "expanding device," "vasospasm," "subarachnoid hemorrhage." Original studies reporting treatment outcomes for vasospasm by using SR/ES in more than 5 patients were included. Pooled data from 8 studies, comprising 156 patients and 428 targeted vessels treated with stent angioplasty for vasospasm were analyzed. We evaluated rates of angiographic success, complications, recurrence, and neurologic improvement. Meta-analysis was performed by using a random-effects model. The angiographic success rate was 81.8% (95% CI: 70.6-89.3). Subgroup analysis showed a success rate of 86.5% (95% CI: 62.6-96.1) with ES and 80.5% (95%CI: 62.6-93.1) with SR. Overall complication rate was 1.1% (95% CI: 0.0-3.6), due to clot formation or hemorrhage. Recurrence of vasospasm was noted in 12.8% (95% CI: 5.2-28.1) while neurologic improvement was seen in 65.9% (95% CI: 51.1-78.1) of the cases. Finally, it should be noted that all included studies used stent angioplasty in combination with intra-arterial vasodilators. Our meta-analysis is limited by selection and reporting biases, as well as high heterogeneity. Moreover, the overall low quality of available evidence is the main limitation of our results. Combination of stent angioplasty and intra-arterial vasodilators was found to have high rates of angiographic success and low incidences of adverse events. Randomized controlled trials are needed to confirm their efficacy and safety compared with medical and balloon angioplasty treatments.