Elena Zapata-Arriaza, MD

Seners P, Ben Hassen W, Lapergue B, Arquizan C, Heldner, MR, Henon H, Perrin C, Strambo, D, Cottier J-P, Sablot D, et al; for the MINOR-STROKE Collaborators. Prediction of Early Neurological Deterioration in Individuals With Minor Stroke and Large Vessel Occlusion Intended for Intravenous Thrombolysis Alone. JAMA Neurol. 2021;78:321-328.

The conjunction of minor stroke and large vessel occlusion (LVO) occurs in a considerable frequency of patients. The question in the acute phase is always the same: Should we perform mechanical thrombectomy when symptoms are presented? Should we use bridging therapy? We do not have valid clinical trials that answer this question, but Seners and colleagues have performed a multicenter retrospective analysis to identify incidence and predictors of early neurological deterioration due to ischemia (ENDi) and thus develop and validate an easily applicable predictive score of ENDi following IVT in patients with minor stroke (NIHSS ≤ 5) and LVO (ICA T/L, Tandem lesion, M1, M2 and Basilar arteries). ENDi was 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.

After inclusion/exclusion criteria, 729 and 347 patients were included in the derivation and validation cohort. ENDi occurred in 12.1% in the derivation cohort patients and accounted for approximately 90% of END cases. The timing of ENDi after IVT start was within 2 hours in 48%, 2 to 6 hours in 13%, 6 to 12 hours in 8%, and 12 to 24 hours 32% of patients. Among patients with ENDi, 56% underwent rescue MT. ENDi 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. This score showed good discriminative power for ENDi and was successfully validated in the validation cohort. In both cohorts, ENDi probability was approximately 3%, 7%, 20%, and 35% for scores of 0, 1, 2 and 3 to 4, respectively.

The analysis of this paper allows us to conclude the following points: 1) ENDi affected approximately 12% of patients; 2) 3-month functional outcome following ENDi improved with rescue MT but remained poor overall; and 3) more proximal occlusion and longer thrombus were independently associated with ENDi. Therefore, minor strokes with large vessel occlusion are not so minor, and a considerable percentage will worsen in the next hours after the onset of symptoms despite treatment with IVT. Is it really worth using IVT and waiting for the patient’s evolution? Having a technique that has proven its safety and efficacy in ischemic strokes due to large vessel occlusion, should we  go one step ahead and consider mechanical thrombectomy in these patients? Does it make sense to try recanalization with a drug that has much lower reperfusion rates than thrombectomy? It is true that this study has its limitations and that its conclusions should be taken with caution, but it provides a fundamental tool in order to choose those patients with a higher risk of worsening, with the functional consequences that this entails. Perhaps it is time to take a step forward in these cases, and this article provides interesting arguments for it.