Lauren Peruski, DO

Girot J-B, Richard S, Gariel F, Sibon I, Labreuche J, Kyheng M, Gory B, Dargazanli C, Maier B, Consoli A, et al. Predictors of Unexplained Early Neurological Deterioration After Endovascular Treatment for Acute Ischemic Stroke. Stroke. 2020;51:2943-2950.

Endovascular thrombectomy (EVT) has become part of the standard of care for select patients with acute ischemic stroke. Studies regarding optimizing patient selection and improvement in short- and long-term outcomes are an area of research interest. A subset that has been examined includes patients that have experienced “early neurological deterioration.” In most papers, early neurological deterioration is defined as an increase of four or more points on the NIH Stroke Scale (NIHSS) within one day of endovascular treatment. In some cases, the etiology of this clinical worsening is obvious, for example, reperfusion failure, peri-procedural complications, hemorrhagic transformation, or malignant edema. However, a significant proportion of these patients experience a neurologic worsening that is not explained by a known entity. 

This study, conducted as a national, multicenter, prospective, observational EVT registry in France, aimed to identify previously unknown predictors of early neurologic deterioration. The 2078 patients examined had undergone routine stroke care for an ICA, M1/M2, or basilar artery occlusion. All patients had endovascular therapy alone, or in combination with intravenous thrombolysis. Those included had an initial NIHSS >5, and an ASPECT of 6 or more. The outcome examined was an early neurologic deterioration (increase of at least 4 on NIHSS or death within one day of treatment), which occurred in 281/2078 patients. Excluded patients included those that had absence of recanalization (TICI 0-2a), malignant edema, or procedural complications — because these are known causes of early neurologic deterioration. The characteristics of the remaining 128 patients were then examined, as these represented the group of unexplained early neurologic deterioration.

The main finding of the study is that 6.6% of a population of acute ischemic stroke patients, treated by EVT with a baseline NIHSS score >5 and ASPECTS ≥6, experienced unexplained early neurologic deterioration. Independent predictive risk factors that were identified include: diabetes mellitus, prestroke modified Rankin Scale score ≥2, general anesthesia, admission systolic blood pressure, age, number of passes, absence of direct patient admission to an EVT-capable center, and lower pretreatment NIHSS score. As vascular neurologists, we can use these predictors of early neurologic deterioration to guide patient selection for EVT and can use this information when consenting and informing patients about this procedure. This information may even inform how endovascular procedures are performed (maximum number of passes) or how patients are triaged within a community (directly to a comprehensive stroke center versus a satellite center). Additional long-term follow up data would be helpful to guide clinical decision making, as well as follow up brain imaging.