BackgroundBronchial arterial embolization (BAE) has been accepted as an effective treatment for bronchiectasis-related hemoptysis. However, rare clinical trials compare different sizes of specific embolic agents. This study aims to evaluate whether different Embosphere microsphere sizes change the outcome of BAE.MethodsA retrospective review was conducted on consecutive patients with bronchiectatic hemoptysis who were scheduled to undergo BAE treatment during a period from January 2018 to December 2022. The patients received BAE using microspheres of different sizes: group A patients were treated with 500–750 μm microspheres, and group B patients were treated with 700–900 μm microspheres. The cost of embolic microspheres (Chinese Yuan, CNY), duration of hospitalization, complications, and hemoptysis-free survival were compared between patients in group A and those in group B. A Cox proportional hazards regression model was used to identify predictors of recurrent hemoptysis.ResultsMedian follow-up was 30.2 months (range, 20.3–56.5 months). The final analysis included a total of 112 patients (49–77 years of age; 45 men). The patients were divided into two groups: group A (N = 68), which received 500–750 μm Embosphere microspheres, and group B (N = 44), which received 700–900 μm Embosphere microspheres. Except for the cost of embolic microspheres(group A,5314.8 + 1301.5 CNY; group B, 3644.5 + 1192.3 CNY; p = 0.042), there were no statistically significant differences in duration of hospitalization (group A,7.2 + 1.4 days; group B, 8 + 2.4days; p = 0.550), hemoptysis-free survival (group A, 1-year, 2-year, 3-year, 85.9%, 75.8%, 62.9%; group B, 1-year, 2-year, 3-year, 88.4%, 81.2%,59.4%;P = 0.060), and complications(group A,26.5%; group B, 38.6%; p = 0.175) between the two groups. No major complications were observed. The multivariate analysis results revealed that the presence of cystic bronchiectasis (OR 1.61, 95% CI 1.12–2.83; P = 0.001) and systemic arterial-pulmonary shunts (SPSs) (OR 1.52, 95% CI 1.10–2.72; P = 0.028) were independent risk factors for recurrent bleeding.ConclusionsFor the treatment of BAE in patients with bronchiectasis-related hemoptysis, 500–750 μm diameter Embosphere microspheres have a similar efficacy and safety profile compared to 700–900 μm diameter Embosphere microspheres, especially for those without SPSs or cystic bronchiectasis. Furthermore, the utilization of large-sized (700–900 μm) Embosphere microspheres is associated with the reduced cost of an embolic agent.