Abstract 326: Mechanical Thrombectomy in Low NIHSS: Preventing High mRS

Introduction Mechanical thrombectomy (MT) for acute ischemic stroke (AIS) is very effective treatment in patients with high National Institutes of Health Stroke Scale (NIHSS) scores. However, disability can also be seen in patients with NIHSS scores of 0‐5. Besides, clinical deterioration as a result of stroke progression is quite common in patients with large vessel occlusion (LVO). Although there are studies investigating the effectivity of EVT in patients with low NIHSS scores, more comprehensive data are needed on patient selection and safety. In this study we aimed to determine the clinical outcome of patients with low NIHSS scores who underwent mechanical thrombectomy in our center. Methods We conducted a single‐center, retrospective study of a prospectively maintained database of stroke patients presenting with NIHSS scores of 0‐5. Patients who applied within 24 hours from the onset of symptoms were included in the study. Detailed clinical information of the patients such as age, sex and the presence of comorbidities, localization of occlusion, procedural measures were recorded. Clinical outcomes were evaluated with NIHSS scores at 24 hours and mRS 3 months. Results A total of 147 patients were enrolled in this study. Patient presenting with NIHSS<5 within 24 hours of onset and imaging modalities showing large or medium vessel occlusion and diffusion‐perfusion mismatch were evaluated for MT. The mean age was 62.75 ± 14.63 and 85 (57.8%) of the patients were male. A total of 8 (5.4%) patients had occlusion in extracranial ICA, 16 (10.9%) in ICA terminal, 49 (33.3%) in MCA M1, 52 (35.4%) in MCA M2 and 8 (5.4%) in M3, 3 (2.1%) in ACA, whereas 5 (3.4%) patients in basilar artery and 6 (4.1%) patients in PCA. The mean NIHSS on admission was 3.28 ± 1.37 and 3.29 ± 3.95 at 24 hours. The patients with mRS scores of 0‐2 were evaluated as functionally independent. The number of functionally independent patients at 90 days was 108 (79.4%), whereas 15 (10.2%) patients died. Conclusions: In this study low NIHSS patients with underlying vessel occlusion benefit from MT in terms of 3.month mRS. Still large cohort, randomized studies are warranted to show superiority to medical treatment.