Department of Emergency Medicine, Medical University of Vienna, Vienna, Austria.
Division of Cardiovascular and Interventional Radiology, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
Heart. 2019 Apr;105(7):531-537. doi: 10.1136/heartjnl-2018-313705. Epub 2018 Oct 25.
To evaluate the effect of prereperfusion hypothermia initiated in the out-of-hospital setting in awake patients with ST-segment elevation myocardial infarction (STEMI) on myocardial salvage measured by cardiac MRI (CMR).
Hypothermia was initiated within 6 hours of symptom onset by the emergency medical service with surface cooling pads and cold saline, and continued in the cath lab with endovascular cooling (target temperature: ≤35°C at time of reperfusion). Myocardial salvage index (using CMR) was compared in a randomised, controlled, open-label, endpoint blinded trial to a not-cooled group of patients at day 4±2 after the event.
After postrandomisation exclusion of 19 patients a total of 101 patients were included in the intention-to-treat analysis (control group: n=54; hypothermia group: n=47). Target temperature was reached in 38/47 patients (81%) in the intervention group. Study-related interventions resulted in a delay in time from first medical contact to reperfusion of 14 min (control group 89±24 min; hypothermia group 103±21 min; p<0.01). Myocardial salvage index was 0.37 (±0.26) in the control group and 0.43 (±0.27) in the hypothermia group (p=0.27). No differences in cardiac biomarkers or clinical outcomes were found. In a CMR follow-up 6 months after the initial event no significant differences were detected.
Out-of-hospital induced therapeutic hypothermia as an adjunct to primary percutaneous coronary intervention did not improve myocardial salvage in patients with STEMI.
NCT01777750.
评估在院外清醒的 ST 段抬高型心肌梗死（STEMI）患者中预先开始的体外低温对心脏磁共振（CMR）测量的心肌挽救的影响。
通过急诊医疗服务使用表面冷却垫和冷盐水在症状发作后 6 小时内开始低温，在导管室继续进行血管内冷却（目标温度：再灌注时≤35°C）。随机、对照、开放标签、终点盲法试验比较心肌挽救指数（使用 CMR），与事件发生后第 4±2 天未降温的患者进行比较。
在随机分组后排除 19 例患者后，共有 101 例患者纳入意向治疗分析（对照组：n=54；低温组：n=47）。干预组 38/47 例（81%）达到目标温度。研究相关干预导致从首次医疗接触到再灌注的时间延迟了 14 分钟（对照组 89±24 分钟；低温组 103±21 分钟；p<0.01）。对照组的心肌挽救指数为 0.37（±0.26），低温组为 0.43（±0.27）（p=0.27）。未发现心脏生物标志物或临床结局的差异。在初始事件后 6 个月的 CMR 随访中未发现显著差异。
作为经皮冠状动脉介入治疗的辅助手段，院外诱导的治疗性低温并未改善 STEMI 患者的心肌挽救。
NCT01777750。
