Kudenchuk P J, Maynard C, Cobb L A, Wirkus M, Martin J S, Kennedy J W, Weaver W D
Department of Medicine, University of Washington, Seattle 98195-6422, USA.
J Am Coll Cardiol. 1998 Jul;32(1):17-27. doi: 10.1016/s0735-1097(98)00175-2.
We sought to determine whether the prehospital electrocardiogram (ECG) improves the diagnosis of an acute coronary syndrome.
The ECG is the most widely used screening test for evaluating patients with chest pain.
Prehospital and in-hospital ECGs were obtained in 3,027 consecutive patients with symptoms of suspected acute myocardial infarction, 362 of whom were randomized to prehospital versus hospital thrombolysis and 2,665 of whom did not participate in the randomized trial. Prehospital and hospital records were abstracted for clinical characteristics and diagnostic outcome.
ST segment and T and Q wave abnormalities suggestive of myocardial ischemia or infarction were more common on both the prehospital and hospital ECGs of patients with as compared with those without acute coronary syndromes (p < or = 0.00001). Those with prehospital thrombolysis were more likely to show resolution of ST segment elevation by the time of hospital admission (14% vs. 5% in patients treated in the hospital, p = 0.004). In patients not considered for prehospital thrombolysis, both persistent and transient ST segment and T or Q wave abnormalities discriminated those with from those without acute coronary ischemia or infarction. Compared with ST segment elevation on a single ECG, added consideration of dynamic changes in ST segment elevation between serial ECGs improved the sensitivity for an acute coronary syndrome from 34% to 46% and reduced specificity from 96% to 93% (both p < 0.00004). Overall, compared with abnormalities observed on a single ECG, consideration of serial evolution in ST segment, T or Q wave or left bundle branch block (LBBB) abnormalities between the prehospital and initial hospital ECG improved the diagnostic sensitivity for an acute coronary syndrome from 80% to 87%, with a fall in specificity from 60% to 50% (both p < 0.000006).
ECG abnormalities are an early manifestation of acute coronary syndromes and can be identified by the prehospital ECG. Compared with a single ECG, the additional effect of evolving ST segment, T or Q waves or LBBB between serially obtained prehospital and hospital ECGs enhanced the diagnosis of acute coronary syndromes, but with a fall in specificity.
我们试图确定院前心电图（ECG）是否能改善急性冠状动脉综合征的诊断。
ECG是评估胸痛患者最广泛使用的筛查测试。
对3027例连续出现疑似急性心肌梗死症状的患者进行了院前和院内ECG检查，其中362例被随机分为院前溶栓组和院内溶栓组，2665例未参与随机试验。提取院前和院内记录的临床特征和诊断结果。
与无急性冠状动脉综合征的患者相比，疑似急性冠状动脉综合征患者的院前和院内ECG上提示心肌缺血或梗死的ST段、T波和Q波异常更为常见（p≤0.00001）。院前溶栓患者在入院时更有可能出现ST段抬高的缓解（14% vs. 院内治疗患者的5%，p = 0.004）。在未考虑院前溶栓的患者中，持续性和短暂性ST段、T波或Q波异常可区分有无急性冠状动脉缺血或梗死。与单次ECG上的ST段抬高相比，增加对系列ECG之间ST段抬高动态变化的考虑，可使急性冠状动脉综合征的敏感性从34%提高到46%，特异性从96%降低到93%（p均<0.00004）。总体而言，与单次ECG上观察到的异常相比，考虑院前和初始院内ECG之间ST段、T波或Q波或左束支传导阻滞（LBBB）异常的系列演变，可使急性冠状动脉综合征的诊断敏感性从80%提高到87%，特异性从60%降低到50%（p均<0.000006）。
ECG异常是急性冠状动脉综合征的早期表现，可通过院前ECG识别。与单次ECG相比，连续获得的院前和院内ECG之间ST段、T波或Q波或LBBB的演变对急性冠状动脉综合征诊断有额外作用，可提高诊断率，但特异性降低。
