Mitchell Rita G, Stoddard Marcus F, Ben-Yehuda Ori, Aggarwal Kul B, Allenby Kent S, Trillo Raul A, Loyd Ruth, Chang Cheng-Tao, Labovitz Arthur J
St Louis University Health Sciences Center, St Louis, Mo 63110-1250, USA.
Am Heart J. 2002 Nov;144(5):E9. doi: 10.1067/mhj.2002.126114.
beta-Blockers have been shown to reduce both morbidity and mortality rates in patients with acute coronary syndromes. However, because of potential side effects, their use is limited in patients who might benefit the most from such therapy. It was thought that the use of an ultra-short-acting intravenous beta-blocker might produce similar results with fewer complications in those patients with relative contraindications to beta-blocker therapy.
Accordingly, we evaluated the use of esmolol in patients with acute coronary syndromes and relative contraindication to beta-blocker therapy in a prospective randomized trial. One hundred eight patients at 21 sites received an infusion of intravenous esmolol or standard therapy on admission and were followed for 6 weeks from the day of admission. The primary efficacy outcome was a composite event consisting of any of the following that occurred during the index hospitalization: death, myocardial (re)infarction, recurrent ischemia, or arrhythmia as well as silent myocardial ischemia assessed by ambulatory electrocardiographic monitoring. Safety end points including hypotension, bradyarrhythmias, new or worsening congestive heart failure, and bronchospasm were also recorded.
Event rates for primary end points were similar in the 2 groups: death (2% in the standard care group vs 4% in the group receiving esmolol), myocardial (re)infarction (4% standard vs 7% esmolol), ischemia (12% vs 13%), arrhythmias (4% vs 2%), and silent ischemia (13% vs 15%). There was a higher incidence of transient hypotension in the group receiving esmolol (2% vs 16%), but all such events were noted to resolve after discontinuation of the esmolol infusion. There were no additional differences in safety end points: bradycardia (2% for those receiving standard care vs 9% receiving esmolol), new congestive heart failure (10% vs 16%), bronchospasm (0% vs 7%), and heart block (2% vs 2%).
The use of an ultra-short-acting beta-blocker such as esmolol might offer an alternative to patients with contraindications to standard beta-blocker therapy. Although this trial had limited power to detect safety and efficacy differences between the 2 therapies, it was observed that safety end points, which occurred during esmolol administration, resolved readily when the infusions were decreased or discontinued. Additional testing is needed to substantiate these findings.
β受体阻滞剂已被证明可降低急性冠脉综合征患者的发病率和死亡率。然而，由于存在潜在副作用，在可能从这种治疗中获益最大的患者中，其使用受到限制。人们认为，对于那些有β受体阻滞剂治疗相对禁忌证的患者，使用超短效静脉β受体阻滞剂可能会产生类似的效果，且并发症更少。
因此，我们在一项前瞻性随机试验中评估了艾司洛尔在急性冠脉综合征且有β受体阻滞剂治疗相对禁忌证患者中的应用。21个研究点的108例患者在入院时接受静脉注射艾司洛尔或标准治疗，并从入院当天起随访6周。主要疗效结局是一个复合事件，包括在本次住院期间发生的以下任何一种情况：死亡、心肌（再）梗死、复发性缺血、心律失常以及通过动态心电图监测评估的无症状心肌缺血。还记录了包括低血压、缓慢性心律失常、新发或加重的充血性心力衰竭以及支气管痉挛在内的安全性终点。
两组主要终点事件发生率相似：死亡（标准治疗组为2%，接受艾司洛尔治疗组为4%）、心肌（再）梗死（标准治疗组为4%，艾司洛尔组为7%）、缺血（12%对13%）、心律失常（4%对2%）和无症状缺血（13%对15%）。接受艾司洛尔治疗组的短暂性低血压发生率较高（2%对16%），但所有此类事件在停用艾司洛尔输注后均得到缓解。安全性终点方面无其他差异：心动过缓（接受标准治疗者为2%，接受艾司洛尔治疗者为9%）、新发充血性心力衰竭（10%对16%）、支气管痉挛（0%对7%）和心脏传导阻滞（2%对2%）。
对于标准β受体阻滞剂治疗有禁忌证的患者，使用艾司洛尔等超短效β受体阻滞剂可能是一种替代选择。尽管该试验检测两种治疗方法之间安全性和疗效差异的能力有限，但观察到在艾司洛尔给药期间出现的安全性终点，在减少或停止输注时很容易得到缓解。需要进一步试验来证实这些发现。
