Supplementary Material for: Direct Admission versus Secondary Transfer for Acute Stroke Patients Treated with Intravenous Thrombolysis and Thrombectomy: Insights from the Endovascular Treatment in Ischemic Stroke Registry

Background: To date, thrombectomy for large vessel occlusion (LVO) strokes can be performed only in comprehensive stroke centers with thrombectomy capacity. We compared the clinical outcome of patients first referred to a primary stroke center to those admitted directly to a comprehensive stroke center and treated on site in the multicentric observational Endovascular Treatment in Ischemic Stroke (ETIS) registry. Methods: From our perspective, multicenter, observational ETIS registry, we analyzed anterior circulation stroke patients, treated within 8 h, who underwent thrombectomy after thrombolysis and were admitted to a comprehensive stroke center either with drip and ship or mothership. Clinical and safety outcomes were compared between 2 groups. Results: A total of 971 patients were analyzed: 298 were treated with the mothership approach and 673 with drip and ship. Significantly more functional independence (90-day modified Rankin Scale [mRS] 0–2) was achieved in mothership (60.1%) than in drip and ship patients (52.6%; adjusted relative risk [RR] 0.87, 95% CI 0.77–0.98, p = 0.018). Excellent outcome (90-day mRS 0–1) was achieved in 45.3% of the mothership group, compared to 37.9% of the drip and ship group (RR 0.84, 95% CI 0.71–0.98; p = 0.026). According to the distance between the primary stroke center and the comprehensive stroke center, greater functional independence was achieved in mothership than in drip and ship >12.5 miles patients (adjusted RR 0.82; 95% CI 0.71–0.94). Results in the drip-ship group stratified according to time between cerebral imaging and groin puncture (categorized according to the median cut-off: 140 min) were similar. Symptomatic intracerebral hemorrhage rate and mortality within 90 days was similar in both groups (7.5 vs. 5.9%, p = 0.40; 17.4 vs. 16.1%, p = 0.63). Conclusions: Our study suggests that LVO stroke patients directly admitted to a comprehensive stroke center present a higher chance of functional independence, especially when the distance between the primary stroke center and comprehensive stroke center is >12.5 miles or when the time between cerebral imaging and groin puncture is ≥140 min.