Incidence and mechanism of early neurological deterioration after endovascular thrombectomy.

Background: We investigated the prevalence and mechanisms of neurological deterioration after endovascular thrombectomy.

Methods: Between January 2011 and October 2017, acute ischemic stroke patients treated by endovascular thrombectomy in a tertiary university hospital were included. Early neurological deterioration (END) was defined as an increase of 2 or more National Institute of Health Stroke Scale (NIHSS) compared to the best neurological status after stroke within 7 days. The END mechanism was categorized into ischemia progression, symptomatic hemorrhage, and brain edema.

Results: A total of 125 acute ischemic stroke patients received endovascular thrombectomy. Neurological deterioration was detected in 44 patients, and 38 cases (86.4% of END) occurred within 72 h. The END mechanism included 20 ischemia progression, 16 brain edema and 8 hemorrhagic transformation cases. Multivariable logistic regression analysis revealed that the patients who experienced END were more likely to have poor functional outcome defined as modified Rankin scale 3-6 at 90 days than neurologically stable patients (odds ratio (OR) = 4.06, confidence interval (CI) = 1.39-11.9). The risk factor of END due to ischemia progression was stroke subtype of large artery atherosclerosis (OR = 6.28, CI = 1.79-22.0). Successful recanalization (OR = 0.11, CI = 0.03-0.39) and NIHSS after endovascular thrombectomy (OR = 1.15 per one-point increase, CI = 1.06-1.24) were significantly associated with END due to hemorrhage or brain edema.

Conclusion: Neurological deterioration frequently occurs after endovascular thrombectomy, and the risk factors of END differ according to the mechanism of END.