Development and validation of a nomogram for predicting 30-day outcomes in patients with unruptured vertebrobasilar dissecting aneurysms undergoing endovascular treatment: a multicenter cohort study

BACKGROUND: Endovascular treatment (EVT) of vertebrobasilar dissecting aneurysms (VBDAs) is associated with high morbidity and mortality, significantly influencing patient prognosis. This study aimed to develop and validate a nomogram for predicting 30-day outcomes in patients with unruptured VBDAs undergoing EVT. METHODS: This retrospective study included 606 patients with unruptured VBDAs who underwent EVT at 10 institutions between January 2015 and April 2025, with 491 in the training cohort and 115 in the validation cohort. Poor outcome was defined as a modified Rankin Scale score ≥3. Predictors were identified via least absolute shrinkage and selection operator analysis and multivariable regression analysis. A nomogram was developed using these predictors. The predictive accuracy and clinical utility of the nomogram were evaluated using area under the curve (AUC), calibration curves, and decision curve analysis (DCA). RESULTS: Over a 30-day follow-up, 44 patients (9.0%) in the training cohort and 13 patients (11.3%) in the validation cohort experienced poor outcomes. Multivariate logistic regression identified ischemic stroke history (OR 3.393, P=0.021), aneurysms located in the vertebrobasilar artery (OR 2.552, P=0.009), type IV VBDA (OR 1.762, P=0.013), overlapping devices (OR 2.736, P=0.007), and aneurysm width (OR 1.101, P=0.043) as predictors of 30-day poor outcome. A nomogram incorporating these predictors yielded AUCs of 0.851 (95% CI 0.784 to 0.918) and 0.860 (95% CI 0.722 to 0.999) in the training and validation cohorts, respectively. The calibration curve and DCA analyses validate the nomogram's clinical utility. CONCLUSION: The nomogram provides an individualized prediction of poor outcomes after EVT, serving as a practical risk assessment tool for patients with unruptured VBDAs.