Time Matters: Adjusted Analysis of the Influence of Direct Transfer to Angiography-Suite Protocol in Functional Outcome

Background and Purpose - Direct transfer to angiography-suite (DTAS) protocol is a promising measure to improve onset to recanalization time in patients who undergo endovascular treatment. The magnitude of the improvement of good outcome rates in function of time depends of several factors. We aim to analyze the benefit of DTAS according to time from symptom onset. Methods - Retrospective case-control study of 174 consecutive DTAS cases matched with 175 patients initially transferred to computed tomography (directly transferred to computed tomography) from February 2016 to June 2019. To obtain comparable groups on admission, cases and controls were matched by occlusion location, age (±2 years), baseline National Institutes of Health Stroke Scale score (±2 points), and time from symptoms onset to hospital arrival (±30 minutes). We analyzed the rate of good functional outcome at 3 months (modified Rankin Scale score, 0-2) and safety variables stratified in less or more than 3 hours from onset to arrive. Results - There were no significant differences regarding age, sex, or baseline National Institutes of Health Stroke Scale score. Median door-to-groin time was shorter in the DTAS patients (16 [3-21] minutes versus 70 [41.5-98.5]; P<0.01). DTAS patients presented lower National Institutes of Health Stroke Scale score at 24 hours (9 [3.5-17] versus 14 [5-19]; P=0.01) and a lower rate of symptomatic hemorrhagic transformation (4.6% versus 10.9%, P<0.03). At 90 days, DTAS patients had a higher rate of good functional outcome (43% versus 29%; odds ratio, 1.81 [95% CI, 1.14-2.87]; P=0.01). Better outcome in DTAS was observed in patients admitted in the 0 to 3 hours form onset window (n=156, odds ratio 2.63 [95% CI, 1.31-5.28]; P<0.01), but not in patients admitted in the 3 to 6 hours window (n=193, odds ratio, 1.37 [95% CI, 0.72-2.60]; P=0.2). Conclusions - DTAS seems a feasible and safe strategy to improve functional outcome in patients who undergo endovascular treatment mainly within 3 hours from symptoms onset.