Abstract WP26: Validation of Predictive Scales of Functional Outcome After Endovascular Therapy Using the REVASCAT Data

Abstract

Introduction: Various scales have been developed to predict long-term clinical outcome after endovascular therapy (EVT) in stroke patients. The objective of this study was to validate and compare five well-validated scales in terms of predictive accuracy for functional independence in a recent endovascular stroke trial (REVASCAT). Hypothesis: We hypothesize that predictive scales (PRE, THRIVE, HIAT2, SPAN-100, FAR) have good-excellent (AUC>0.7) predictive accuracy for good functional outcome and can predict the beneficial effect of EVT demonstrated in randomized clinical trials. Methods: REVASCAT (Randomized Trial of Revascularization with Solitaire-FR Device versus Best Medical Therapy in the Treatment of Acute Stroke Due to Anterior Circulation Large Vessel Occlusion Presenting within Eight Hours of Symptom Onset) enrolled 206 patients who were randomized to receive EVT or best medical treatment. Five scores (PRE-score, THRIVE, HIAT2, SPAN-100 and FAR-score) were retrospectively calculated on patients who received EVT. Receiver-operator characteristics (ROC) for good outcome (mRS 0-2 at 90 days) for each scale were compared. Using the highest predictive scales, the proportion of patients with good outcome by the score categorized in quartiles was analyzed. Results: 103 patients received EVT in the REVASCAT trial (mean age 65.7, median NIHSS 17). Baseline NIHSS, baseline CT-ASPECTS, age and atrial fibrillation, but not previous iv tPA or DM, were associated with good outcome in multivariable analysis. AUC for good outcome was ≥0.70 for FAR (0.74) and PRE (0.70) scores while SPAN-100 (0.67), HIAT2 (0.65) and THRIVE (0.64) had lower AUCs although differences were not statistically significant. The higher the score on the PRE and FAR scores, the lower the proportion of patients with good outcome (PRE-score: 1QT 44.4%, 2QT 24.4%, 3QT 22.2%, 4 QT 8.9%; FAR-score: 1QT 57.8%, 2QT 22.2%, 3QT 6.7%, 4QT 3.3%). Benefit of EVT accordingly to the score on the different scales will be also presented. Conclusions: Of the 5 stroke scales, FAR and PRE had better predictive accuracy for functional independence after EVT. These tools may facilitate decision making for EVT in anterior circulation large vessel occlusion stroke.