Abstract WP21: “Stunned Brain”– Early versus Delayed Clinical Recovery After Neurothrombectomy

Abstract

Introduction: Heterogeneity in early neurological improvement after neurothrombectomy for large vessel occlusion (LVO) stroke is well documented. Delayed clinical recovery is observed in a subset of patients who do not experience early improvement. Understanding the temporality of clinical recovery after thrombectomy is essential in guiding prognostication and targeting rehabilitation. In this study, we aim to describe the characteristics and incidence of early and delayed clinical recovery and identify their predictors after LVO stroke thrombectomy. Methods: A retrospective analysis of prospectively-collected data on patients undergoing anterior circulation LVO stroke thrombectomy. Demographic characteristics, clinical and radiological data, treatment and procedural information were extracted and analyzed. Characteristics and predictors of early clinical recovery (ECR-1-NIHSS <6 at 24 hours and ECR-2-mRS 0-2 at discharge) and delayed clinical recovery (DCR-1 and 2- mRS 0-2 at 90 days) were analyzed. Statistical analyses were performed on SPSS 23 (IBM, Armonk, NY). Results: Three hundred and fifty-five patients met study criteria. 55% (195) were females and mean age was 71±15 years. Mean NIHSS score and median ASPECTS were 17±6 and 9 (8-10), respectively. ECR-1 and ECR-2 were observed in 31% (115) and 21% (73) patients, respectively. Among non-ECR patients, delayed recovery was observed in 27-30% of patients. Lower NIHSS [OR-0.83 (0.75-0.91), p=<0.01] and higher ASPECTS [OR-2.14, (1.29-3.54), p=0.003] scores were independent predictors of ECR-1 and younger age [OR-0.96 (0.94-0.99), p=0.01] and absence on parenchymal hemorrhage (PH) [OR-3.1 (1.3-7.1), p=0.007] were independent predictors of DCR-1. Among non-early improvers, patients <80 years and without PH have a 40% chance of DCR compared to no patients over 80 years with parenchymal hemorrhage experiencing DCR. Conclusion: About one-third of patients experience early clinical recovery (ECR-1-31%) and approximately one-third (DCR-1-30%) of non-early improvers experience delayed clinical recovery. Lower NIHSS score and higher ASPECTS predict ECR while younger age and absence of parenchymal hemorrhage predict DCR.