Abstract TP002: Door-to-Reperfusion Time Is More Strongly Associated with Poor Outcomes Than Onset-to-Door Time in Mechanical Thrombectomy for Acute Ischemic Stroke

Background: In mechanical thrombectomy (MT) for acute ischemic stroke with large vessel occlusion, a shorter time from onset to reperfusion is associated with a higher frequency of favorable outcomes. However, when the total time is divided into onset-to-door time (OTD) and door-to-reperfusion time (DTR), it remains unclear which has a greater impact on patient outcomes. Methods: Using our prospectively maintained registry, we analyzed 1,984 consecutive stroke patients who were admitted to our hospital between January 2018 and October 2024. Among them, those who underwent mechanical thrombectomy (MT) were included in this study. Patients with pre-stroke mRS > 4 or without accurate time data were excluded. Poor outcome (PO) was defined as a modified Rankin Scale (mRS) score of 5–6 at 90 days, and good outcome (GO) as mRS 0–4. Patients were categorized into two groups, GO and PO. Odds ratios (OR) for poor outcome were calculated for each 30-minute delay in OTD and DTR. Results: A total of 138 patients were included (median age 72 years; 93 males [67.4%]; median NIHSS 17). Intravenous thrombolysis was performed in 63 patients (45.7%). At 90 days, 46 patients (33.3%) had poor outcomes (mRS 5–6). There was no significant difference in OTD between GO and PO groups (74 [37-178] min vs 120 [50-217] min, p = 0.186). In contrast, DTR was significantly longer in the PO group (173 [137-213] min vs 218 [157-269] min, p = 0.013). The impact of a 30-minute delay on poor outcome was greater for DTR (OR 1.094, 95% CI 0.987–1.213) than for OTD (OR 1.003, 95% CI 0.958–1.050). Conclusions: In patients undergoing MT, delays in OTD were not associated with poor outcomes, whereas delays in DTR showed a tendency to be associated with poor outcomes. Specifically, each 30-minute delay in DTR was associated with a point estimate of a 9.4% increase in the odds of poor outcome, highlighting the importance of achieving reperfusion as quickly as possible after hospital arrival. Importantly, since current practice often leaves room for further reduction in DTR, these findings suggest that systematic efforts to streamline in-hospital workflows could translate into tangible improvements in patient outcomes.