Effect of Early Neuroendovascular Team Involvement in Acute Stroke Protocol: A Retrospective Study

HITOSHI MORI^1*Masahiro Kashiura²Ichiro Suzuki³Fumiko Ono⁴Yuya Yoshimura⁴Takashi Moriya²

• ¹Department of Emergency and Critical Care Medicine, Hachinohe City Hospital, Hachinohe, Aomori, Japan, Department of Emergency and Critical Care Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan
• ²Department of Emergency and Critical Care Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan
• ³Department of Neurosurgery, Hachinohe City Hospital, Hachinohe, Aomori, Japan, Hachinohe, Japan
• ⁴Department of Emergency and Critical Care Medicine, Hachinohe City Hospital, Hachinohe, Japan

Introduction: Acute ischemic stroke (AIS) is a leading cause of morbidity and mortality, with outcomes dependent on timely treatment. Tissue plasminogen activator (tPA) and endovascular therapy (EVT) improve outcomes, but delays reduce their efficacy. This study introduced a protocol featuring early participation of neuroendovascular interventionists and evaluated its association with treatment times and outcomes compared with conventional management. Methods: This singlecenter retrospective study included patients with AIS transported to emergency room (ER) who received tPA or EVT between January 2010 and December 2022. Under the protocol, the stroke team-including neuroendovascular interventionists, who made the final decision on tPA and EVTwas activated by the emergency physician when stroke was suspected based on pre-hospital information. The stroke team was not activated if neuroendovascular interventionists were engaged in other procedures or if the ER physician suspected a non-stroke diagnosis. Upon arrival, the team commenced care, with neuroendovascular interventionists reviewing imaging and determining treatment strategies. Patients were categorized into protocol and conventional groups based on management under the new protocol or standard care. The primary outcome was a favorable neurological outcome, defined as a modified Rankin Scale (mRS) score of 0-2 at discharge. Secondary outcomes included time metrics for initiation of tPA and/or EVT. Logistic regression analysis estimated the effects of the protocol, adjusting for confounders, including age, sex, baseline National Institutes of Health Stroke Scale score, and pre-hospital factors. Secondary outcomes were assessed using multiple linear regression. Results: This study analyzed 501 patients, with 313 in the protocol group and 188 in the conventional group. Favorable neurological outcomes at discharge (mRS 0-2) were more frequent in the protocol group (44.4% vs. 31.9%; adjusted odds ratio: 2.92, 95% confidence interval [CI]: 1.83-4.66). The protocol group also showed shorter door-to-imaging time (-8.3 min), door-to-needle time (-55.9 min), door-to-puncture time (-59.8 min), and door-torecanalization time (-73.7 min). Conclusions: Early engagement of neuroendovascular specialists in the emergency pathway was associated with faster treatment initiation and a higher likelihood of favorable functional status at discharge in this retrospective cohort. Because residual confounding and temporal changes in stroke care cannot be excluded, prospective validation in other settings is warranted.