Outcomes and predictors of intraprocedural rupture in patients with cerebral aneurysm

Background: Intraprocedural rupture (IPR) is a devastating complication of cerebral aneurysm treatment. While several studies have investigated its risk factors and clinical impact, further research with larger populations is warranted. Methods: We retrospectively reviewed data from 4,039 patients with 4,233 cerebral aneurysms treated at our institution between January 2009 and December 2018. Multivariate logistic regression with stepwise elimination was performed to identify the independent risk factors of IPR. Unfavorable clinical outcome was defined as a Modified Rankin Scale (mRS) >= 3 points at 3 months post-treatment. Results: IPR occurred in 61 (1.44%) of the 4,233 aneurysms. Multivariate analysis showed that previously ruptured aneurysms (odds ratio [OR] 3.182; 95% confidence interval [CI] 1.851-5.470; p < 0.001), surgical clipping (OR 3.598; 95% CI 1.894-6.836; p < 0.001), and higher aspect ratio (OR 1.310; 95% CI 1.032-1.663; p = 0.024) were independent risk factors for IPR. Patients with IPR had significantly higher rates of unfavorable clinical outcomes (mRS >= 3) compared to those without (18.0% vs. 3.3%, p < 0.001). However, within the ruptured aneurysm subgroup, the rate of unfavorable outcomes did not differ significantly between IPR and non-IPR groups (22.7% vs. 19.2%, p = 0.594). Conclusion: Ruptured aneurysms, surgical clipping, and higher aspect ratio were independently associated with IPR. IPR significantly increased the risk of unfavorable clinical outcomes regardless of treatment approach, except in the subgroup of ruptured aneurysms.