Left Ventricular Unloading in Anterior ST-Segment Elevation Myocardial Infarction Without Shock: The ST-Segment Elevation Myocardial Infarction Door to Unload Randomized Controlled Trial.

Left ventricular (LV) wall tension and load are major determinants of infarct size.

左心室（LV）壁张力和负荷是决定梗死大小的主要因素。

Preclinical studies identified that delaying reperfusion to permit LV unloading with a transvalvular microaxial flow pump (TV-mAFP) reduces infarct size.

临床前研究发现，延迟再灌注以允许使用经瓣膜微轴流泵（TV-mAFP）进行左心室卸载可以减少梗死面积。

We tested whether this combination reduces infarct size compared with reperfusion alone in patients with anterior STEMI without cardiogenic shock.

我们测试了这种组合是否能在没有心源性休克的前壁STEMI患者中减少梗死面积，与单独再灌注相比。

The STEMI-Door to Unload (DTU) pivotal trial tested the central hypothesis that the combination of mechanical LV unloading plus a 30-minute delay before PCI reduces infarct size compared with immediate PCI alone in patients with anterior STEMI without cardiogenic shock.

STEMI-Door to Unload (DTU) 关键试验测试了中心假设，即机械性左心室卸载与PCI前30分钟延迟相结合，与仅立即PCI相比，可以减少无心源性休克的前壁STEMI患者的梗死面积。

Methods

We conducted an open-label, randomized controlled trialat 55 hospitals in the United States, Germany, Italy, United Kingdom, Switzerland, and Canada.

我们在美国、德国、意大利、英国、瑞士和加拿大的55家医院进行了一项开放标签、随机对照试验。

Adults aged 18 to 85 years with no prior myocardial infarction and presenting with acute anterior STEMI within 1 to 6 hours of symptom onset before hospital arrival were eligible for inclusion.

年龄在18至85岁之间，之前没有心肌梗死病史，并且在症状发作后1至6小时内到达医院前出现急性前壁ST段抬高型心肌梗死（STEMI）的成人符合纳入标准。

Patients were randomly assigned (1:1) by study site personnel to either LV unloading with a TV-mAFP for 30 minutes before PCI (treatment group) or PCI alone (control group).

患者按1:1的比例随机分配，由研究现场人员分配至左心室卸载组，使用经胸主动脉内反搏（TV-mAFP）30分钟后再进行经皮冠状动脉介入治疗（PCI）（治疗组），或仅接受PCI（对照组）。

The primary outcome was infarct size normalized to LV mass (IS/LVM) evaluated by cardiac magnetic resonance imaging 3 to 5 days after PCI and was evaluated in all randomized patients.

主要结果是在PCI后3至5天通过心脏磁共振成像评估的心肌梗死大小标准化为左心室质量（IS/LVM），并在所有随机患者中进行评估。

The trial is closed to new participants.

该试验已对新参与者关闭。

Results

Between December 12, 2019 and September 3, 2024, 527 patients were randomized; 262 patients were assigned to the treatment group and 265 to the control group.

在2019年12月12日至2024年9月3日期间，共有527名患者被随机分配；其中262名患者被分配到治疗组，265名患者被分配到对照组。

Mean patient age was 61 ± 11 years, and 417 patients (79.1%) were men.

患者的平均年龄为61±11岁，其中417名患者（占79.1%）为男性。

Total ischemic time was longer in the treatment arm.

治疗组的总缺血时间更长。

IS/LVM was 30.8% ± 16.2% in the treatment group and 31.9% ± 16.9% in the control group (mean difference: -1.1%; 95% CI: -4.2 to 2.0; P = 0.50).

治疗组的IS/LVM为30.8% ± 16.2%，对照组为31.9% ± 16.9%（平均差异：-1.1%；95% 置信区间：-4.2至2.0；P = 0.50）。

Major bleeding or vascular complications at 30-day follow-up occurred more frequently in the treatment group when compared with either a prespecified performance goal or the control group.

在30天随访期间，治疗组的主要出血或血管并发症发生率较预先设定的性能目标或对照组更高。

Conclusions

Combination of a TV-mAFP plus delayed PCI did not reduce infarct size in patients with anterior STEMI without cardiogenic shock compared with PCI alone.

在没有心源性休克的前壁ST段抬高型心肌梗死患者中，联合使用TV-mAFP和延迟PCI并未比单独使用PCI减少梗死面积。

(Primary Unloading and Delayed Reperfusion in ST-Elevation Myocardial Infarction: The STEMI-DTU Trial [DTU-STEMI]; NCT03947619).

(STEMI-DTU试验[DTU-STEMI]; NCT03947619)：ST段抬高型心肌梗死的初级卸载和延迟再灌注。