To evaluate mechanical thrombectomy (MT) benefits on acute large vessel occlusion (LVO) stroke patients who were transferred to a comprehensive stroke center (CSC).

All MT cases between 2015-2017 were categorized into two groups: transferred group (TG) and mothership group (MG). Demographics, stroke severity, recanalization rate, Time from last known normal to groin puncture (TNP) were reviewed. TICI score 2b or higher was good recanalization. Favorable outcome was mRS 0-2. Fish Exact and Mann Whitney test were used for statistical analysis.

TG had 46 patients, and MG had 70. Mean age of TG was 64 years old (yo) and that MG was 63 yo. NIHSS on admission (median(IQR25-75%)) was similar: TG was17(12-20) vs AG 17(13-20). TNP median time (IQR25-75%) in the TG was 397(275-615)min vs 267(196-541) min in the MG,(p=0.122). TG had 80% good recanalization, and MG had 72%. However, MG had significant better outcomes than TG(33.8% vs 17.4%,p=0.03). Favorable outcome in TG was less than MG(17.4% vs 33.8%,p=0.08). For MT cases that were started within 8hrs after stroke onset, TG still had 102 min longer in median TNP time, with less favorable outcome(22.7% vs 34.6%) than MG.

Our study showed LVO patients who were transferred to a CSC had less favorable outcomes, possibly from longer time lapse from the onset to treatment. We may consider alternative ways to improve MT benefits for those patients, such as “drive interventionalists to local hospitals”, or “new tailored training program that credentials more vascular neurologists to perform MT at remote hospitals without full neurointerventional training”.