Development and validation of the FLATS score to predict periprocedural ischemic events after stent-assisted coiling for ruptured intracranial aneurysms in the acute phase: a nationwide chinese registry.

Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating stroke subtype. In the acute phase (< 72 h), stent-assisted coiling (SAC) carries a substantial risk of ischemic events (IEs). Early identification of high-risk patients is critical to improving outcomes. We developed and validated a practical risk score for predicting IEs, to support individual risk stratification. This prospective registry (SANE registry) included patients with aSAH at 33 advanced stroke centers across China from April 2021 to April 2024. Demographic, radiological and procedural variables collected at hospitalization were screened using Least Absolute Shrinkage and Selection Operator (LASSO) and logistic regression to construct a predictive risk score (FLATS). Model discrimination was assessed by the area under the receiver operating characteristic curve (AUC). An independent external validation cohort was derived from a single tertiary hospital, comprising patients treated between January 2011 and December 2020. The derivation cohort included 1,469 patients (median age: 57 years; 71.0% females) and 196 patients (13.3%) developed IEs. From 18 potential predictors, 5 variables were independent predictive factors and were included in the risk score: age, modified Fisher Scale, aneurysm size and location, and time to surgery. The FLATS score demonstrated good discriminative, with an AUC of 0.808. In external validation (n = 439), the AUC was 0.853. For risk stratification, a FLATS score > 15 was defined as high risk and a score < 10 indicated as lower risk. The FLATS score is an easily applicable aid for risk stratification of IEs after SAC for acute aSAH.  TRIAL REGISTRATION: ChiCTR2000032657 (chictr.org.cn, registered by Beijing Tiantan Hospital on May 5, 2020).