急性心肌梗死诊断中不同心肌标损伤标志物联合应用方案的比较

目的比较不同心肌损伤标志物组合诊断急性心肌梗死(AMI)的价值,探讨心肌型脂肪酸结合蛋白(H-FABP)在增加心肌标志物组合诊断效能方面的作用。方法随机纳入急诊就诊的急性胸痛患者组成待研究人群,定量测定每位患者入院第一管血的血清H-FABP及临床常用的心肌损伤标志物(cTnI,Myo),随后根据WHO标准将研究对象分为AMI与心梗疑似患者。绘制3种标志物用于诊断AMI的ROC曲线。通过ROC曲线确定3种心肌损伤标志物诊断AMI的最佳Cutoff值,并对设计出的3种诊断AMI的心肌损伤标志物组合试验(cTnI Myo、cTnI H-FABP、cTnI Myo H-FABP)的各诊断准确度指标进行比较。结果3种标志物诊断AMI的ROC曲线下面积分别为:AUCcTnI0．938(95％CI 0．888-0．988),AUCMyo0．743(95％CI 0．651-0．836),AUCH-FABP 0．919 (95％CI 0．873-0．964);根据ROC曲线确定的各指标用于诊断AMI的cutoff值分别为CutoffcTnI 0．5 ng／mL,CutoffMyo90 ng／mL,CutoffH-FABP 5．7 ng／mL。据此推算的各心肌损伤标志物及其组合诊断AMI的敏感度(按cTnI、Myo、H-FABP、cTnI Myo、cTnI H-FABP、cTnI Myo H-FABP的顺序)分别为0．804、0．674、0．783、0．957、0．957、0．957;特异度分别为0．966、0．747、0．954、0．724、0．92、0．724;诊断符合率分别为0．910、0.722、0．895、0．805、0．932、0．805。与“cTnI H-FABP”相比,敏感度cTnI(z=2．261,P=0．024)、Myo(Z=3．497,P<0．001)、H-FABP(Z=2．478,P=0．013)、特异度Myo (Z=3．062,P=0．002)、cTnI Myo(Z=3．378,P<0．001)、cTnI Myo H-FABP (Z=3．378,P<0．001)、诊断符合率Myo(Z=4．528,P<0．001)、cTnI Myo (Z=3．064,P=0．002)、cTnI Myo H-FABP(Z=3．064,P=0．002)与之的差异均具有统计学意义。结论“cTnI H-FABP”心肌损伤标志物组合诊断AMI表现出最高的诊断敏感度与较高的诊断特异度,其在临床出现急性胸痛人群中诊断AMI的价值优于目前临床使用的心肌损伤标志物组合。

A Comparison of Different Combination Regimens of Biochemical Markers in Diagnosing Acute Myocardial Infarction

Objective To compare the diagnostic accuracy of different combination regimens of myocardial infarction markers in diagnosing acute myocardial infarction; and to estimate the effect of heart-type fatty acid-binding protein (H-FABP) in improving the diagnostic accuracy of the combinations. Methods Patients with acute onset of chest pain were included randomly. Serum concentrations of H-FABP and other biochemical markers for myocardial infarction (cTnI, Myo) were determined immediately, and then acute myocardial infarction (AMI) patients were defined according to the WHO criteria. ROC curves for three biochemical markers were established respectively, and the cutoff values of the three markers were determined accordingly. Three combination regimens of myocardial infarction markers for AMI diagnosis were designed: cTnI Myo, cTnI H-FABP, cTnI H-FABP Myo. Diagnostic accuracy of the three regimens were then calculated and compared. Results The AUCs for the three biochemical markers were AUCcTnI 0.938 (95%CI: 0.888-0.988), AUCMyo 0.743 (95%CI: 0.651-0.836), and AUCH-FABP 0.919 (95%CI: 0.873-0.964), respectively. AUCH-FABP was significantly larger than AUCMyo(P<0.01). The cutoff values of the three biochemical markers for diagnosing AMI were defined as CutoffcTnI 0.5 ng/mL, CutoffMyo 90 ng/mL, and CutoffH-FABP 5.7 ng/mL, respectively. The diagnostic accuracy of these markers and their combination regimens were calculated and presented as follows (cTnI, Myo, H-FABP, cTnI Myo, cTnI H-FABP, cTnI Myo H-FABP): sensitivity: 0.804, 0.674, 0.783, 0.957, 0.957 ard 0.957; specificity: 0.966, 0.747, 0.954, 0.724, 0.92 and 0.724; diagnostic efficacy: 0.910, 0.722, 0.895, 0.805, 0.932 and 0.805, respectively. Compared with the combination of cTnI H-FABP, the sensitivities of cTnI (Z=2.26I, P=0.024), Myo (Z=3.497, P<0.001) and H-FABP (Z=2.478, P=0.013) were significantly lower; the specificities of Myo (Z=3.062, P=0.002), cTnI Myo (Z=3.378, P<0.001) and cTnI Myo H-FABP (Z=3.378, P<0.001) were significantly lower; and the diagnostic efficacies of Myo (Z=4.528, P<0.001), cTnI Myo (Z=3.064, P=0.002) and cTnI Myo H-FABP (Z=3.064,P=0.002) were significantly lower. Conclusion The combination regimen of cTnI H-FABP which includes H-FABP as the sensitive marker seems to be more effective than the currently used combinations in diagnosing AMI in patients with acute onset of chest pain.