Prediction of Early Neurological Deterioration in Individuals With Minor Stroke and Large Vessel Occlusion Intended for Intravenous Thrombolysis Alone

Abstract

Importance: The best reperfusion strategy in patients with acute minor stroke and large vessel occlusion (LVO) is unknown. Accurately predicting early neurological deterioration of presumed ischemic origin (ENDi) following intravenous thrombolysis (IVT) in this population may help to select candidates for immediate transfer for additional thrombectomy.

Objective: To develop and validate an easily applicable predictive score of ENDi following IVT in patients with minor stroke and LVO.

Design, setting, and participants: This multicentric retrospective cohort included 729 consecutive patients with minor stroke (National Institutes of Health Stroke Scale [NIHSS] score of 5 or less) and LVO (basilar artery, internal carotid artery, first [M1] or second [M2] segment of middle cerebral artery) intended for IVT alone in 45 French stroke centers, ie, including those who eventually received rescue thrombectomy because of ENDi. For external validation, another cohort of 347 patients with similar inclusion criteria was collected from 9 additional centers. Data were collected from January 2018 to September 2019.

Main outcomes and measures: ENDi, defined as 4 or more points' deterioration on NIHSS score within the first 24 hours without parenchymal hemorrhage on follow-up imaging or another identified cause.

Results: Of the 729 patients in the derivation cohort, 335 (46.0%) were male, and the mean (SD) age was 70 (15) years; of the 347 patients in the validation cohort, 190 (54.8%) were male, and the mean (SD) age was 69 (15) years. In the derivation cohort, the median (interquartile range) NIHSS score was 3 (1-4), and the occlusion site was the internal carotid artery in 97 patients (13.3%), M1 in 207 (28.4%), M2 in 395 (54.2%), and basilar artery in 30 (4.1%). ENDi occurred in 88 patients (12.1%; 95% CI, 9.7-14.4) and was strongly associated with poorer 3-month outcomes, even in patients who underwent rescue thrombectomy. In multivariable analysis, a more proximal occlusion site and a longer thrombus were independently associated with ENDi. A 4-point score derived from these variables-1 point for thrombus length and 3 points for occlusion site-showed good discriminative power for ENDi (C statistic = 0.76; 95% CI, 0.70-0.82) and was successfully validated in the validation cohort (ENDi rate, 11.0% [38 of 347]; C statistic = 0.78; 95% CI, 0.70-0.86). In both cohorts, ENDi probability was approximately 3%, 7%, 20%, and 35% for scores of 0, 1, 2 and 3 to 4, respectively.

Conclusions and relevance: The substantial ENDi rates observed in these cohorts highlights the current debate regarding whether to directly transfer patients with IVT-treated minor stroke and LVO for additional thrombectomy. Based on the strong associations observed, an easily applicable score for ENDi risk prediction that may assist decision-making was derived and externally validated.

Conflict of interest statement

Conflict of Interest Disclosures: Dr Lapergue has received grants from Stryker Neurovascular, Penumbra, MicroVention, and Balt. Dr Heldner has received grants from Bangerter Foundation and honoraria for serving on the scientific advisory board from Amgen. Dr Strambo has received grants from Swiss Heart Foundation and University of Lausanne. Dr Béjot has received personal fees from AstraZeneca, Bristol Myers Squibb, Pfizer, Medtronic, MSD France, Amgen, Servier Laboratories, and Boehringer Ingelheim. No other disclosures were reported.

Figures

Figure 1.. Three-Month Modified Rankin Scale (mRS) Scores According to Early Neurological Deterioration of Presumed Ischemic Origin (ENDi) Status and Rescue Thrombectomy Status in the ENDi Subgroup in the Derivation Cohort

mRS score was not available for 37 patients (5 patients with ENDi and 32 with no early neurological deterioration [END]).

Figure 2.. Early Neurological Deterioration of Presumed Ischemic Origin (ENDi) as a Function of Occlusion Site and Thrombus Length in the Derivation Cohort

A, ENDi rates according to each occlusion site. Error bars indicate 95% CIs. B, The regression curve estimates the probability of ENDi according to thrombus length. The shaded area depicts the 95% CIs (logistic regression model). END indicates early neurological deterioration; ICA-T/L, T or L intracranial internal carotid artery; M1, first segment of the middle cerebral artery; M2, second segment of the middle cerebral artery.

Figure 3.. The ENDi Score for Prediction of Early Neurological Deterioration of Presumed Ischemic Origin (ENDi) in Patients With Minor Stroke Due to Intracranial Large Vessel Occlusion

A, ENDi risk prediction score. B, Probability of ENDi according to incremental points on the ENDi score applied to the derivation and validation cohorts. Incremental points are presented on the x-axis and probability of ENDi on the y-axis. Error bars indicate the 95% CIs. ICA-T/L indicates T or L intracranial internal carotid artery; M1, first segment of the middle cerebral artery; M2, second segment of the middle cerebral artery.