Table 1. Overview of Derivation Cohort and Validation Cohorta.
| Characteristic | Derivation cohort HERMES (n = 781) | Validation cohort MR CLEAN registry (n = 3260) |
|---|---|---|
| Age, median (IQR), y | 67 (57-76) | 72 (61-80) |
| Sex, No./total No. (%) | ||
| Men | 414/781 (53) | 1684/3260 (52) |
| Women | 367/781 (47) | 1576/3260 (48) |
| NIHSS score, median (IQR) | 17 (14-21) | 16 (11-19) |
| Systolic blood pressure, median (IQR), mm Hg | 144 (130-159) | 150 (131-165) |
| Serum glucose level, median (IQR), mmol/L | 6.7 (5.9-7.8) | 6.8 (5.9-8.1) |
| Previous stroke, No./total No. (%) | 89/777 (11) | 544/3233 (17) |
| Hypertension, No./total No. (%) | 426/779 (55) | 1676/3194 (52) |
| Atrial fibrillation, No./total No. (%) | 217/640 (34) | 770/3217 (24) |
| Diabetes, No./total No. (%) | 120/780 (15) | 524/3236 (16) |
| Prestroke mRS score, No./total No. (%) | ||
| 0 | 501/605 (83) | 2160/3188 (68) |
| 1 | 76/605 (13) | 421/31888 (13) |
| 2 | 19/605 (3.1) | 239/3188 (7.5) |
| ≥3 | 9/605 (1.5) | 368/3188 (12) |
| Occlusion location, No./total No. (%) | ||
| ICA(-T) | 198/733 (27) | 818/3121 (26) |
| M1 | 473/733 (65) | 1804/3121 (58) |
| M2 or otherb | 62/733 (8.5) | 499/3121 (16) |
| ASPECTS scale, median (IQR) | 8 (7-9) | 9 (7-10) |
| Collateral score, No./total No. (%) | ||
| 0 | 5/602 (0.8) | 187/3053 (6.1) |
| 1 | 81/602 (14) | 1094/3053 (36) |
| 2 | 268/602 (45) | 1181/3053 (39) |
| 3 | 248/602 (41) | 591/3053 (19) |
| Treatment with IV alteplase, No./total No. (%) | 678/781 (87) | 2445/3248 (75) |
| Time from stroke onset to arterial puncture, median (IQR), min | 240 (185-299) | 195 (150-255) |
| General anesthesia, No./total No. (%) | 227/776 (29) | 775/3063 (25) |
| Duration of the procedure, median (IQR), min | 64 (40-91) | 59 (38-83) |
| Outcome measures | ||
| Reperfusion grade (mTICI), No./total No. (%) | ||
| 0 | 54/715 (7.6) | 531/3173 (17) |
| 1 | 19/715 (2.7) | 94/3173 (3.0) |
| 2A | 98/715 (14) | 592/3173 (19) |
| 2B | 483/715 (68) | 715/3173 (23)c |
| 2C | NA | 339/3173 (11)c |
| 3 | 61/715 (8.5) | 902/3173 (28) |
| NIHSS score at 24 h, median (IQR) | 9 (4-16) | 10 (4-17) |
| sICH at 24 h, No./total No. (%) | 28/770 (3.6) | 192/3245 (5.9) |
| FIV 12 h to 2 wk, median (IQR) mL | 34 (11-103) | NA |
| mRS score at 3 mo, median (IQR) | 3 (1-4) | 3 (2-6) |
| mRS 0-2 at 3 mo, No./total No. (%) | 371/781 (48) | 1235/3047 (41) |
| Survival at 3 mo, No./total No. (%) | 671/781 (86) | 2164/3047 (71) |
Abbreviations: ASPECTS, Alberta Stroke Program Early CT Score; FIV, follow-up infarct volume; HERMES, Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke Trials; ICA(-T), intracranial carotid artery (terminus); IV, intravenous; M1, middle cerebral artery segment 1; M2, middle cerebral artery segment 2; MR CLEAN, Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands; mRS, modified Rankin Scale; mTICI, modified treatment in cerebral infarction; NA, not applicable; NIHSS, National Institutes of Health Stroke Scale; sICH, symptomatic intracranial hemorrhage.
SI conversion factor: To convert glucose level to milligrams per deciliter, divide by 0.0555.
Categorical values are presented as No. (%) and continuous values as median (IQR). Missing continuous values in the derivation cohort and validation cohort, respectively, are 0 and 15 for age; 4 and 55 for NIHSS baseline score; 1 and 89 for systolic blood pressure; 26 and 371 for serum glucose; 8 and 109 for ASPECTS scale; 0 and 15 for time from stroke onset to arterial puncture; 174 and 291 for duration of the procedure; and 25 and 333 for NIHSS score at 24 hours.
Other occlusion location (M3 or anterior cerebral artery segment 1 or 2) by core laboratory: in HERMES (n = 1), in MR CLEAN Registry (n = 25).
Extended TICI score MR CLEAN Registry: 2B (n = 715), 2C (n = 339).