Supplementary Material for: Mechanical thrombectomy treatment beyond 16 hours from last known well in patients with large vessel occlusion

Introduction: Mechanical thrombectomy (MT) has been reported to be effective within 24 h after last known well (LKW) by the DAWN (DWI or CTP Assessment with Clinical Mismatch in the Triage of Wake-Up and Late Presenting Strokes Undergoing Neurointervention with Trevo) trial and within 16 h after LKW by the DEFUSE-3 (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke 3) trial. However, there have been few reports of MT more than 16 h after LKW, and the efficacy and safety of MT more than 24 h after LKW have not yet been demonstrated. We evaluated the efficacy and safety of MT more than 16 h after LKW.
Methods: Using data from the Nippon Medical School Hospital MT registry from April 2011 to August 2022, consecutive patients with anterior circulation large vessel occlusion (LVO) and prehospital modified Rankin scale (mRS) scores of 0–3 were enrolled. Patients were classified into the following three groups: early group (LKW <6 h); middle group (LKW 6–16 h); and late group (LKW >16 h). The clinical characteristics and outcomes were compared among these three groups.
Results: Among 778 patients in the MT registry, 624 were enrolled. The early group included 432 patients, the middle group included 123 patients, and the late group included 69 patients. The patients had a median age of 77 years (interquartile range, 68–83) and 359 were male (57.5%). The median prehospital mRS score was 1 (interquartile range, 1–1), median National Institutes of Health Stroke Scale score on admission was 17 (interquartile range, 10–23), and median Alberta Stroke Program Early CT score was 10 (interquartile range, 8–10). Regarding safety and efficacy, the proportions of cases with successful reperfusion (modified Thrombolysis in Cerebral Infarction score of 2b–3; 85.4% vs 92.7% vs 88.7%; P=.47), symptomatic intracranial haemorrhage (6.4% vs 5.7% vs 7.2%; P=.99), mRS score ≤3 at 90 days (52.0% vs 60.2% vs 44.9%; P=.11), and mRS score of 6 at 90 days (11.3% vs 10.6 vs 8.7%; P=.37) were not significantly different between the three groups.
Conclusion: Patients who received MT more than 16 h after LKW experienced the same safety and efficacy as those who received MT at 0–16 h after LKW. MT more than 16 h after LKW may be safe and effective for stroke patients with LVO.

引言：既往DAWN试验（DWI或CTP评估觉醒及晚期就诊卒中患者行Trevo神经介入治疗中的临床错配分诊，DAWN）证实，机械取栓术（Mechanical thrombectomy, MT）在最后已知正常时间（last known well, LKW）后24小时内均有效；DEFUSE-3试验（缺血性卒中影像学评估后血管内治疗3，DEFUSE-3）则证实其在LKW后16小时内有效。然而，目前关于LKW后16小时以上行MT的报道极少，且LKW后24小时以上行MT的有效性与安全性尚未得到证实。本研究旨在评估LKW后16小时以上行MT的有效性与安全性。

方法：本研究纳入2011年4月至2022年8月日本医科大学附属医院MT登记数据库中的连续病例，入选标准为前循环大血管闭塞（LVO）且院前改良Rankin量表（mRS）评分0~3分的患者。将患者分为三组：早期组（LKW<6小时）、中期组（LKW 6~16小时）及晚期组（LKW>16小时），比较三组患者的临床特征与结局。

结果：该MT登记数据库中共收录778例患者，最终纳入624例。其中早期组432例，中期组123例，晚期组69例。所有入组患者的中位年龄为77岁（四分位间距：68~83），男性359例，占比57.5%。院前mRS评分中位数为1（四分位间距：1~1），入院时美国国立卫生研究院卒中量表（NIHSS）评分中位数为17（四分位间距：10~23），阿尔伯塔卒中项目早期CT评分（ASPECTS）中位数为10（四分位间距：8~10）。在安全性与有效性方面，三组患者的成功再灌注率（改良脑梗死溶栓分级mTICI 2b~3级：85.4% vs 92.7% vs 88.7%；P=0.47）、症状性颅内出血发生率（6.4% vs 5.7% vs 7.2%；P=0.99）、90天mRS评分≤3分比例（52.0% vs 60.2% vs 44.9%；P=0.11）及90天mRS评分6分比例（11.3% vs 10.6% vs 8.7%；P=0.37）均无显著统计学差异。

结论：LKW后16小时以上接受MT的患者，其安全性与有效性与LKW后0~16小时接受MT的患者相当。LKW后16小时以上行MT或可用于前循环大血管闭塞的卒中患者，且兼具安全性与有效性。