缺血修饰清蛋白在急性心肌缺血早期诊断中的临床价值

Clinical significance of ischemia modified albumin for the early diagnosis of acute cardiac ischemia

目的探讨血清缺血修饰清蛋白(IMA)测定在急性心肌缺血早期的临床价值。方法采用间接清蛋白-钴结合实验(ACB)测定80例确诊为急性冠状动脉综合征(ACS)的患者及60例因胸痛入院但最后确诊为非缺血性心脏病患者,胸痛发作3h内的血清IMA水平和临床常用的心肌损伤标志物心肌肌钙蛋白T(cTnT)、肌酸激酶同工酶(CK-MB)。通过绘制ACB在该人群中用于诊断ACS的受试者工作特征(ROC)曲线判定最佳临界值,确定IMA诊断ACS的敏感性、特异性、阳性预测值和阴性预测值。结果与对照组比较,ACS组ACB明显降低,为(49.75±10.25)U/mL,经t检验,差异有统计学意义(P<0.01),而ACS组中,急性心肌梗死(AMI)组与不稳定型心绞痛(UA)组间ACB比较差异无统计学意义(P>0.05);cTnT、CK-MB水平分别为(1.24±0.67)ng/mL、(35.14±9.37)U/L,经t检验,差异无统计学意义(P>0.05)。根据ROC曲线,当cut-off值为63.6U/mL时,IMA检测的敏感性、特异性、阳性预测值和阴性预测值较高,分别为81.27%、86.58%、84.19%和82.57%。结论缺血修饰清蛋白是早期诊断心肌缺血的敏感标志物,对于急性冠状动脉综合征的早期诊断和治疗具有重要的临床意义。

Objective To discuss the clinical significance of ischemia modified albumin （IMA） for the early diagnosis of acute cardiac ischemia（ACI）.Methods Indirect albumin cobalt binding （ACB） test was performed to measure the serum IMA level and routine methods were performed for the detection of cardiac troponin T （cTnT） and creatine kinase isoenzyme MB （CK-MB） within 3 hours after the onset of thoracalgia in 80 cases of patients with definite diagnosis of acute coronary syndrome（ACS） and 60 patients with chest pain while finally diagnosed as non-ischemic heart diseases.By preparing receiver operating characteristic（ROC） curve,based on ACB value,the optimal cut-off value of IMA for the diagnosis of ACS was confirmed,and related sensitivity,specificity,positive predictive value and negative predictive value were calculated.Results Compared with control group,ACB value of ACS group was significantly lower,as （49.75±10.25）U/mL,with the statistically significant difference by t test（P0.01）,while in ACS group,there was no significant difference in ACB values between acute myocardial infarction （AMI） group and unstable angina（UA） group （P0.05）.In ACS group,serum levels of cTnT and CK-MB were （1.24±0.67）ng/mL and （35.14±9.37）U/L respectively,without statistical difference with control group by t test（P0.05）.According to ROC curve,when cut-off value was 63.6 U/mL,the sensitivity,specificity,positive predictive value and negative predictive value of IMA for the diagnosis of ACS were relatively high,as 81.27%,86.58%,84.19% and 82.57% respectively.Conclusion IMA could be an sensitive marker for the early diagnosis of cardiac ischemia,with clinical significance for the early diagnosis and cure of ACS.