New Risk Score Found to Successfully Predict Neurological Deterioration of Ischemic Origin in Minor Stroke, LVO

Using a derived and externally validated risk score, researchers were able to predict neurological deterioration of ischemic origin (END_i) among patients with minor stroke and large vessel occlusion (LVO) treated with intravenous thrombolysis (IVT), according to new findings published in JAMA Neurology.

Investigators arrived at their conclusion after performing a multicentric retrospective cohort study of 729 consecutive patients (mean age 70 years) across 45 stroke centers in France (derivation cohort). All patients included in the study had minor stroke, defined as a National Institutes of Health Stroke Scale (NIHSS) score of 5 or less; and LVO of the basilar artery, first (M1) or second (M2) segment of middle cerebral artery, or internal carotid artery. All patients had been intended for IVT alone in 45 French stroke centers, and some eventually underwent rescue thrombectomy because of END_i. A validation cohort (n = 347; mean age 69 years) with similar inclusion criteria across 9 other centers was included.

The main outcome of the study was defined as END_i: deterioration of 4 or more points on NIHSS score within the initial 24 hours without evidence of parenchymal hemorrhage on follow-up imaging or other cause.

The median NIHSS score in the derivation cohort was 3, and the occlusion site was the internal carotid artery, M1, M2, and basilar artery in 97, 207, 395, and 30 patients, respectively. Eighty-eight patients (12.1%) experienced END_i, which demonstrated a strong association with poorer outcomes at 3 months, including among those who received rescue thrombectomy. Multivariable analysis demonstrated independent associations of more proximal site of occlusion and a longer thrombus with END_i.

Using these variables, the researchers derived a 4-point score, with 1 point for the length of the thrombus and 3 points for the site of occlusion. Ultimately, they found that the score demonstrated good discriminative power for END_i and was able to be confirmed in the validation cohort, in which 38 of 347 patients (11.0%) had END_i.

The probability of END_i was found to be approximately 3% for a score of 0, 7% for a score of 1, 20% for a score of 2, and 35% for a score of 3 to 4 in both cohorts.

“The substantial END_i 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,” the researchers wrote. “Based on the strong associations observed, an easily applicable score for END_i risk prediction that may assist decision-making was derived and externally validated.”

—Christina Vogt

Reference:
Seners P, Ben Hassen W, Lapergue B, et al. Prediction of early neurological deterioration in individuals with minor stroke and large vessel occlusion intended for intravenous thrombolysis alone. JAMA Neurol. Published online January 11, 2021. doi:10.1001/jamaneurol.2020.4557