Green G B, Beaudreau R W, Chan D W, DeLong D, Kelley C A, Kelen G D
Department of Emergency Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Ann Emerg Med. 1998 Jan;31(1):19-29. doi: 10.1016/s0196-0644(98)70276-8.
To evaluate and compare the utility of measurement of troponin T and the creatine kinase MB subunit (CK-MB) for risk stratification of ED patients with possible myocardial ischemia.
Prospective observational study of ED patients with symptoms of possible myocardial ischemia with early, single sample serologic testing for cardiac troponin T and CK-MB using an identity-unlinked process. Chart review (ED, inpatient, outpatient), and telephone and mail surveys identified adverse events (AEs) during the 14 days following enrollment. AEs recorded included death, respiratory or cardiac arrest, myocardial infarction (MI), atrial and ventricular arrhythmias, pulmonary edema, conduction disturbances, and recurrent angina. Measures of the predictive ability for AEs were calculated for troponin T, CK-MB, and a combined troponin T/CK-MB index (defined as positive if either troponin T or CK-MB levels exceeded threshold values).
Among 292 study patients, 45 (15.4%) experienced at least one AE, including seven deaths and 12 MIs. The troponin T result was positive in 34 patients, and the CK-MB result was positive in 15 patients; 6 patients had positive results for both markers and 43 patients had a positive combined troponin T/CK-MB index. Odds ratios (ORs) for occurrence of AEs among all patients were 4.4 (1.8 to 10.2), 10.0 (3.0 to 36.0), and 4.5 (2.0 to 9.8) for troponin T, CK-MB and the troponin T/CK-MB index, respectively. Both markers were individually predictive of AEs (troponin T = 4.3; CK-MB = 7.5) among all those with chest pain. Only the CK-MB level was significantly predictive of AEs among those presenting with symptoms other than chest pain (OR = 24.3 [1.1, 1448]), whereas only the troponin T level was significantly predictive among patients representing a disposition dilemma for the emergency physician (OR = 5.7 [1.4, 20.7]). When compared, the ORs for troponin T and CK-MB were not significantly different for any patient subgroup. The troponin T/CK-MB index did not have a higher prognostic value than either troponin T or CK-MB alone in any subgroup studied.
A positive test result for either troponin T or CK-MB in the ED successfully identified patients at significantly higher risk of adverse events during the 2 weeks following their ED visit. The two markers may complement each other in that each appears to have prognostic ability among a unique patient subgroup. ED marker measurement can provide useful prognostic information for patients with a broad spectrum of presentations consistent with possible myocardial ischemia.
评估并比较肌钙蛋白T和肌酸激酶MB亚单位（CK-MB）检测在对可能存在心肌缺血的急诊患者进行风险分层中的效用。
对有心肌缺血可能症状的急诊患者进行前瞻性观察研究，采用身份无关流程对心脏肌钙蛋白T和CK-MB进行早期单样本血清学检测。通过病历审查（急诊、住院、门诊）以及电话和邮件调查确定入组后14天内的不良事件（AE）。记录的AE包括死亡、呼吸或心脏骤停、心肌梗死（MI）、房性和室性心律失常、肺水肿、传导障碍以及复发性心绞痛。计算肌钙蛋白T、CK-MB以及肌钙蛋白T/CK-MB联合指标（定义为肌钙蛋白T或CK-MB水平超过阈值即为阳性）对AE的预测能力。
在292例研究患者中，45例（15.4%）经历了至少一次AE，包括7例死亡和12例MI。34例患者肌钙蛋白T结果为阳性，15例患者CK-MB结果为阳性；6例患者两种标志物结果均为阳性，43例患者肌钙蛋白T/CK-MB联合指标为阳性。所有患者中发生AE的比值比（OR），肌钙蛋白T为4.4（1.8至10.2），CK-MB为10.0（3.0至36.0），肌钙蛋白T/CK-MB联合指标为4.5（2.0至9.8）。在所有胸痛患者中，两种标志物各自对AE均有预测作用（肌钙蛋白T = 4.3；CK-MB = 7.5）。在表现为非胸痛症状的患者中，只有CK-MB水平对AE有显著预测作用（OR = 24.3 [1.1, 1448]），而在给急诊医生带来处置难题的患者中，只有肌钙蛋白T水平有显著预测作用（OR = 5.7 [1.4, 20.7]）。比较时，在任何患者亚组中，肌钙蛋白T和CK-MB的OR均无显著差异。在任何研究的亚组中，肌钙蛋白T/CK-MB联合指标的预后价值均不高于单独的肌钙蛋白T或CK-MB。
急诊时肌钙蛋白T或CK-MB检测结果为阳性成功识别出在急诊就诊后2周内发生不良事件风险显著更高的患者。这两种标志物可能相互补充，因为它们似乎在不同的独特患者亚组中均具有预后判断能力。急诊标志物检测可为表现出与可能心肌缺血相符的广泛症状的患者提供有用的预后信息。
