Introduction Patients with large vessel occlusion (LVO) stroke are often transferred from primary to tertiary stroke centres for endovascular thrombectomy (EVT). We previously showed that ≥33% improvement in National Institute of Health Stroke Scale (NIHSS) score correlated with early recanalization obviating need for EVT. We aimed to validate this correlation and assess cost savings if non-invasive imaging was performed prior to digital subtraction angiography (DSA). Methods Patients transferred to an Australian tertiary stroke centre for possible EVT between January 2023 and April 2024 and underwent DSA with or without EVT were included. Changes in NIHSS between transfer and arrival, demographic, treatment and anatomical factors were collected. NIHSS changes were correlated with early recanalization. Real-time costs of in- and out-of-hours neuroimaging and DSA were calculated. Results 257 transferred patients with LVO were included (30% female, median age 71[IQR 61-79) ). Median presentation NIHSS was 14 (IQR 10-19). 129 (50%) patients received intravenous thrombolytics. 27 (11%) patients demonstrated early recanalization and did not require EVT. Threshold of ≥33% NIHSS improvement remained the best trade-off between sensitivity (74%) and specificity (88%) for recanalization. The hyperacute investigation and treatment costs in/out-of-hours per patient was 1491 and 3591. Costs if patients with ≥33% NIHSS improvement were non-invasively imaged prior to DSA was 1471 and 3548 –savings of 34 per patient overall. Conclusion We validated that ≥33% neurological recovery between primary and tertiary stroke centre had the best sensitivity-specificity profile for predicting early recanalization. Modest cost savings occurred using this threshold, but in resource-poor settings this may be more significant.
Sharma et al. (Fri,) studied this question.