Patient characteristics in 2199 patients with anterior circulation LVO stroke treated in the early (<6 hours) and late (6–24 hours) time windows. Missing data were <2% for all variables
| Variable | Early window reference n=1690, % (n) | Late window known onset n=141, % (n) | Late window LSW n=368, % (n) | P value |
| Patient characteristics | ||||
| Age median (IQR) | 73 (64–80) | 74 (64–80) | 73 (64–80) | 0.996 |
| Female sex | 46.7% (790) | 46.1% (65) | 43.5% (160) | 0.522 |
| Hypertension | 58.3% (984) | 55.4% (77) | 60.9% (223) | 0.483 |
| Atrial fibrillation | 45.4% (767) | 41.8% (59) | 46.7% (172) | 0.611 |
| Diabetes | 15.6% (264) | 15.7% (22) | 16.6% (61) | 0.896 |
| Previous stroke | 10.8% (183) | 12.9% (18) | 11.1% (41) | 0.764 |
| Stroke characteristics | ||||
| Median NIHSS (IQR) | 16 (11–20) | 12 (7–17) | 15 (11–19) | <0.001 |
| Wake-up stroke | 3.2% (54) | 0% (0) | 61.1% (225) | <0.001 |
| Occlusion location | ||||
| First imaging (CTA) | 0.167 | |||
| ICA | 24.6% (400) | 16.3% (23) | 21.3% (76) | |
| MCA, M1 | 56.9% (927) | 61.0% (86) | 58.8% (210) | |
| MCA, M2 | 18.5% (302) | 22.7% (32) | 19.9% (71) | |
| DSA | 0.039 | |||
| ICA | 19.3% (327) | 14.9% (21) | 20.9% (77) | |
| MCA, M1 | 51.2% (866) | 46.1% (65) | 54.1% (199) | |
| MCA, M2 | 29.4% (497) | 39.0% (55) | 25.0% (92) | |
| Partial recanalization (all) | 14.9% (251) | 17.7% (25) | 7.1% (26) | <0.001 |
| In IVT patients (n=1175) | 18.9% (199) | 24.3% (18) | 20.4% (10) | 0.513 |
| Medical and EVT treatment and process times | ||||
| IVT treatment | 62.2% (1052) | 52.5% (74) | 13.3% (49) | <0.001 |
| Median DTN (IQR) | 29 (18–44) | 40 (24–56) | 47 (27–72) | <0.001 |
| Median OTN (IQR) | 95 (75–125) | 137 (93–185) | 233 (139–272) | <0.001 |
| Secondary transport to CSC | 57.7% (972) | 92.2% (130) | 66.8% (245) | <0.001 |
| Median OTG (IQR) | 192 (141–251) | 435 (395–515) | 551 (442–710) | <0.001 |
| Median NTG (IQR) | 87 (50–145) | 288 (230–347) | 206 (122–347) | <0.001 |
| Median OTR (IQR) | 254 (192–322) | 499 (449–576) | 619 (501–765) | <0.001 |
| Reperfusion rate | 0.141 | |||
| mTICI 2b–3 | 84.9% (1418) | 80.6% (112) | 87.5% (321) | |
| Anesthesia | 0.006 | |||
| Conscious sedation | 64.7% (1091) | 51.8% (73) | 61.4% (226) | |
| General anesthesia | 35.3% (594) | 48.2% (68) | 38.6% (142) | |
| EVT technique | 0.762 | |||
| DAC | 20.7% (349) | 19.9% (28) | 19.8% (73) | |
| Stent retriever + DAC | 74.8% (1264) | 76.6% (108) | 77.4% (285) | |
| Other | 1.2% (21) | 1.4% (2) | 0.8% (3) | |
| Only attempt | 3.3% (56) | 2.1% (3) | 1.9% (7) | |
| Early neurological outcome | ||||
| 24 hours NIHSS, median (IQR) | 6 (2–14) | 7 (3–15) | 8 (3–16) | 0.002 |
| Adverse events | ||||
| sICH | 4.0% (67) | 2.1% (3) | 4.9% (18) | 0.413 |
| Procedural complication | 12.9% (165) | 10.4% (12) | 12.1% (38) | 0.717 |
| Post-procedural complication | 31.8% (395) | 29.6% (34) | 22.9% (71) | 0.01 |
CSC, comprehensive stroke center; CTA, CT angiography; DAC, direct aspiration catheter; DSA, digital subtraction angiography; DTN, door-to-needle; EVT, endovascular thrombectomy; ICA, internal carotid artery; IVT, intravenous thrombolysis; LSW, last seen well; LVO, large vessel occlusion; MCA, middle cerebral artery; mTICI, modified Treatment In Cerebral Infarction; NIHSS, National Institutes of Health Stroke Scale; NTG, needle-to-groin; OTG, onset-to-groin; OTN, onset-to-needle; OTR, onset-to-revascularization; sICH, symptomatic intracerebral hemorrhage.