Lynn Jeremy S, Singh Amandeep, Snoey Eric R
Department of Emergency Medicine, Alameda County Medical Center, Highland Hospital, Oakland, CA 94602-1018, USA.
ISRN Cardiol. 2011;2011:364728. doi: 10.5402/2011/364728. Epub 2011 Apr 12.
Background. The use of a single troponin measurement to exclude the diagnosis of non-ST segment myocardial infarction (NSTEMI) in patients that present with ischemic symptom duration ≥8 hours is sometimes used in the Emergency Department. Study Objective. To describe the characteristics of patients with initial nondiagnostic troponin values who develop a positive troponin while in the Emergency Department and to evaluate whether NSTEMI can be excluded using symptom duration ≥8 hours and initial troponin I. Methods. Retrospective chart review of patients evaluated for NSTEMI in the Emergency Department. Results. 4,510 patients had at least two troponin I values obtained during the two-year study period. 115 (2.5%) of these patients had an initially nondiagnostic (<0.6 ng/mL) and subsequent positive (≥0.6 ng/mL) troponin I result. Twenty-five (22%) of the 115 had duration of symptoms ≥8 hours. Of these 25 patients, 18 had an intermediate first troponin value (i.e., >0.06 ng/mL, but <0.6 ng/mL). Only two of the remaining seven patients had a final primary diagnosis of NSTEMI. Conclusion. The use of a negative initial troponin I together with a symptom onset of ≥8 hours defines a population with a very low incidence of a hospital diagnosis of NSTEMI.
背景。急诊科有时会使用单次肌钙蛋白检测来排除缺血症状持续时间≥8小时患者的非ST段抬高型心肌梗死（NSTEMI）诊断。研究目的。描述急诊科初始肌钙蛋白值未确诊但随后肌钙蛋白转为阳性的患者特征，并评估是否可使用症状持续时间≥8小时和初始肌钙蛋白I来排除NSTEMI。方法。对急诊科评估为NSTEMI的患者进行回顾性病历审查。结果。在为期两年的研究期间，4510例患者至少检测了两次肌钙蛋白I值。其中115例（2.5%）患者初始肌钙蛋白I值未确诊（<0.6 ng/mL），随后转为阳性（≥0.6 ng/mL）。115例中有25例（22%）症状持续时间≥8小时。在这25例患者中，18例首次肌钙蛋白值处于中间水平（即>0.06 ng/mL，但<0.6 ng/mL）。其余7例患者中只有2例最终主要诊断为NSTEMI。结论。初始肌钙蛋白I阴性且症状发作≥8小时的患者群体，医院诊断为NSTEMI的发生率非常低。
