Outcome of patients with large vessel occlusion in the anterior circulation and low NIHSS score

Background Optimal management of patients with large vessel occlusion (LVO) and low NIHSS score is unknown, which was the aim to investigate in this study. Methods This is a retrospective analysis of a prospective single tertiary care centre 14-year cohort of patients with LVO in the anterior circulation and NIHSS score ≤ 5 on admission. Outcome was analysed according to primary intended therapy. Results Among 185 patients (median age 67.4 years), 52.4% received primary conservative therapy (including 26.8% secondary reperfusion in case of secondary neurological deterioration), 12.4% IV thrombolysis (IVT) only and 35.1% primary endovascular therapy (EVT). 95 (51.4%) patients experienced neurological deterioration until 3 months. Primary-IVT-only and primary-EVT compared to conservative-therapy patients had better 3 months’ outcome (54.5% vs. 30.8%: adjusted OR 6.02; adjusted p = 0.004 for mRS 0–1 and 54.7% vs. 30.8%: adjusted OR 5.09; adjusted p = 0.002, respectively). Also mRS shift analysis favored primary-IVT-only and primary-EVT patients ( adjusted OR 6.25; adjusted p = 0.001 and adjusted OR 3.14; adjusted p = 0.003). Outcome in primary-IVT-only vs. primary-EVT patients did not differ significantly. Patients who received secondary EVT because of neurological deterioration after primary-conservative-therapy had worse 3 months’ outcome than primary-EVT patients (20.8% vs. 30.8%: adjusted OR 0.24; adjusted p = 0.047 for mRS 0–1 and adjusted OR 0.31; adjusted p = 0.019 in mRS shift analysis). Survival and symptomatic intracranial haemorrhage did not differ amongst groups. Conclusions Our data indicate that primary IVT and/or EVT may be better than primary conservative therapy in patients with LVO in the anterior circulation and low NIHSS score. Furthermore, primary EVT was better than secondary EVT in case of neurological deterioration. There is an unmet need for RCTs to find the optimal therapy for this patient group.