Abstract Body: Introduction: Faster reperfusion from initial presentation was associated with improved outcomes after endovascular thrombectomy(EVT) in patients with small core strokes. However, the relationship between time and different workflow metrics with outcomes in not well-established in patients with large strokes. We aimed to analyze the clinical workflow and time measures and their effect on overall procedure and functional outcomes from SELECT2 trial.
Methods: Patients enrolled in SELECT2 trial were stratified based on treatment arm and transfer status and various workflow metrics, both in-hospital and outside (limited to transferred patients) were compared and their effect on clinical outcomes were evaluated.
Results: Of 352 enrolled, 141 patients (72 EVT, 69 MM) presented directly to EVT-capable centers, whereas 211(106 EVT, 105 MM) were transferred from referral centers. Among patients presenting directly, no difference was observed between time from LKW to arrival(EVT:376.5(119.5-638)min vs MM:435(118-802)min,p=0.50), arrival to imaging acquisition(EVT:14(10-21)min vs MM:16.5(11-25)min,p=0.21) or time from imaging to randomization(EVT:55(40.5-72.5)min vs MM:64(44-84)min,p=0.083)-Fig1a. For patients transferred to EVT-capable centers, no difference was observed between treatment arms in time from LKW to arrival - EVT:418(63-757)min vs MM:313(87.5-713)min,p=0.77; time from arrival to imaging – EVT:12(3.5-24)min vs MM:13.5(10-20)min,p=0.12; time from imaging to departure – EVT:123.5(82-195)min vs MM:128.5(85-197.5)min,p=0.95; transit time to EVT center – EVT:39(21.5-67)min vs MM:38.5(25.5-67.5)min,p=0.73); time from imaging to randomization – EVT:43(21-70)min vs MM:39(21-68)min,p=0.96)-Fig1b. Longer procedure time was associated with worse mRS (aGenOR:0.92, 95%CI:0.87-0.96,p-value:0.001 for every 10min). Longer time from perfusion imaging to reperfusion was associated with worse mRS in both direct(aGenOR:0.99(0.99-1.00),p=0.003 for every 10min) and transferred patients(aGenOR:0.98(0.95-1.00),p=0.038 for every 10min) fig2, but Interfacility transfer times or other time metrics were not significantly associated with functional outcomes.

Conclusion: In large ischemic core infarct patients randomized in the SELECT2 trial, longer times from imaging to reperfusion and procedure time were associated with worse clinical outcomes after thrombectomy. Expedited and efficient workflow protocols at thrombectomy centers are vital to optimize outcomes in large core patients.