缺血修饰白蛋白在急性冠状动脉综合征危险分层中的诊断价值

Diagnositic value of ischemia modified albumin in risk stratification for acute coronary syndrome

目的:评估缺血修饰白蛋白(IMA)作为心肌缺血标志物在急性冠状动脉综合征(ACS)危险分层中的诊断价值。方法:入选2007年1月至2009年10月在我院救治的发病6h内可疑缺血性胸痛,且不符合急性ST段抬高心肌梗死(STEMI)诊断标准者。全数患者在入院即刻分别检测IMA、cTnT、CK-MB,并在发病12h后再次检测cT-nT。由2名心脏科专家在对IMA不知情的情况下,分别做出12h和临床最终诊断。根据12hcTnT结果和临床最终诊断,分别计算IMA诊断精确度。结果:313例可疑胸痛者中12hcTnT阳性、最终诊断ACS者分别为116和163例。对预测12hcTnT阳性,以急诊即刻cTnT特异性(99.49%)、阳性预测值(96.55%)、阳性似然比(47.31)最高,IMA测值最低;IMA敏感性(94.83%)、阴性预测值(95.59%)最高,阴性似然比(0.08)最低,IMA阴性组有6例患者12hcTnT阳性。对最终诊断ACS,IMA的特异性(90.79%)和敏感性(74%)均较低。163例最终诊断为ACS的患者中,非ST段抬高心肌梗死(NSTEMI)66例,STEMI30例,不稳定型心绞痛(UA)67例。3组IMA水平无显著差异,但较非ACS组IMA水平显著升高。结论:IMA存在少数假阴性,使临床安全性受限。由于IMA极低的检验特异性,且无法区别UA和急性心肌梗死,因此对ACS危险分层价值不高。

Objective：To evaluate the diagnositic value of ischemia modified albumin （IMA） as a biomarker of cardiac ischemia in risk stratification for acute coronary syndrome （ACS）. Methods：Consecutive patients presenting with suspicious ischemic chest pain and without evidence of ST segment elevation myocardial infarction（STEMI） were enrolled. Serum levels of IMA,cTnT,CK-MB at presentation and delayed cTnT taken at 12h after pain onset were measured. The final clinic diagnosis was made by 2 cardiologists who were blind to the results of IMA. The diagnostic accuracy for IMA was calculated based on 12h cTnT results and the final clinical diagnosis. Results：Amony 313 patients with suspected chest pains, 116 were 12h cTnT positive ACS, and 163 were ACS in the final diagnosis, resulting in specificity （99.49%）, positive predictive value （96.55%）, positive likelihood ratio （47.31）. For IMA test values, sensitivity （94.83 % ）, negative predictive value （95.59% ） were the highest, negative likelihood ratio （0.08） was low. In the IMA-negative group, 6 patients were 12h cTnT positive. In patients with final diagnosis of ACS, IMA specificity （90.79%） and sensitivity （74%） were lower. Out of the 163 cases diagnosed as ACS, there were 66 cases with non-ST-segment elevation myocardial infarction （NSTEMI）, 30 cases STEMI, and 67 found among the three IMA groups, but cases unstable the IMA level angina （UA）. in the non-ACS Conclusion：This study suggests that there is a small portion of false safe use as a clinical test indicator. In the meantime, the extremely low and inability to distinguish UA from acute myocardial infarction （AMI） risk stratification approach. No significant differences were group was significantly higher. negative IMA, which limits its level of test specificity of IMA denote a low value of the ACS