Can early neurological improvement after mechanical thrombectomy be used as a surrogate for final stroke outcome?

Abstract

Background and purposeWe aimed to identify the best definition of early neurological improvement (ENI) at 2 and 24 hours after mechanical thrombectomy (MT) and determine its ability to predict a good functional outcome at 3 months.MethodsThis retrospective analysis was based on a prospectively collected registry of patients treated by MT for ischemic stroke from May 2010 to March 2017. We included patients treated with stent-retrievers with National Institute of Health Stroke Scale (NIHSS) score before treatment and at 2 and/or 24 hours after treatment and modified Rankin Score (mRS) at 3 months. Receiver operating characteristic curve analysis was performed to estimate optimal thresholds for ENI at 2 and 24 hours. The relationship between optimal ENI definitions and good outcome at 3 months (mRS 0–2) was assessed by logistic regression.ResultsThe analysis included 246 patients. At 2 hours, the optimal threshold to predict a good outcome at 3 months was improvementin the NIHSS score of >1 point (AUC 0.83,95% CI 0.77 to 0.87), with sensitivity and specificity 78.3% (62.2–85.7%) and 84.6% (77.2–90.3%), respectively, and OR 12.67 (95% CI 4.69 to 31.10, p<0.0001). At 24 hours, the optimal threshold was an improvementin the NIHSS score of >4 points (AUC 0.93, 95% CI 0.89 to 0.96), with sensitivity and specificity 93.8% (87.7–97.5%) and 83.2% (75.7–89.2%), respectively, and OR 391.32 (95% CI 44.43 to 3448.35, p<0.0001).ConclusionsENI 24 hours after thrombectomy appears to be a straightforward surrogate of long-term endpoints and may have value in future research.

Predictor of 90-day functional outcome after mechanical thrombectomy for large vessel occlusion stroke: NIHSS score of 10 or less at 24 hours

“…Consistent with those findings, prompt neurological improvement has shown to be more accurate as the baseline NIHSS score increases. 10 Likewise, neurological improvement of NIHSS score ≥ 4 was unable to predict good functional outcome in the large-vessel stroke subset in intravenous tPA and placebo groups. 4…”

“…Soize et al analyzed 246 large-vessel stroke patients treated with thrombectomy and identified the ENI as the most important predictor of 90-day functional outcome. 10 Despite the larger sample size, the study had a number of limitations. Patients were treated between 2010 and 2017.…”

“…Accuracy of rapid neurological improvement (RNI, defined as a reduction of ≥ 8 on the NIHSS or an NIHSS score < 2 at 24 hours after thrombectomy), 3 dramatic neurological improvement (DNI, defined as a reduction of ≥ 10 on the NIHSS or an NIHSS score < 4 at 24 hours), 1,6 and early neurological improvement (ENI, defined as an improvement in NIHSS score > 4 at 24 hours), 10 were assessed and compared to predictors in the current cohort.…”

“…Mechanical thrombectomy and intravenous or sonothrombolysis may follow different neurological recovery kinetics. 10 Successful mechanical thrombectomy establishes reperfusion rapidly while intravenous tPA most commonly fails to recanalize proximal LVO due to the longer and more robust clots. 5 Those studies also included non-LVO strokes that are often associated with lower baseline NIHSS score.…”

Nomogram predicting early neurological improvement in ischaemic stroke patients treated with endovascular thrombectomy

“…Diametrical recovery, namely early neurological improvement (ENI), was observed in a significant proportion of patients within the first 24 h of EVT treatment [2]. ENI has been regarded as a surrogate indicator of effective recanalization [3][4][5] and a reliable prognostic marker after EVT [2,[6][7][8]. However, the definition of ENI in EVT patients remains poorly defined.…”