D-二聚体在急诊主动脉夹层早期诊断的临床应用

目的：探讨血浆D-二聚体水平在急性主动脉夹层中早期诊断的临床价值。方法：回顾性分析我院2011-05-2013-08因急诊胸痛24h内入院患者共285例,所有患者入院即抽血行全血D-二聚体快速测试,比较不同病因组D-二聚体水平。所有数据采用SPSS 16.0统计软件分析处理,计量资料采用珚x±s及中位数（M）、四分位数间距（QR）进行描述,各组间D-二聚体中位数的比较采用Kruskal-Wallis H检验,Nemenyi法进一步两两比较;绘制D-二聚体水平诊断急性主动脉夹层（AAD）的受试者工作曲线（ROC曲线）,分析D-二聚体鉴别急性主动脉夹层的敏感性、特异性、预测值和似然比（P〈0.05认为差异具有统计学意义）。结果：急性主动脉夹层组（AAD）和急性肺栓塞组（APE）血浆D-二聚体水平显著高于急性心肌梗死（AMI）、心绞痛、急性心包炎、急性胸膜炎及其他病因不明的急性胸痛病例组;AMI组D-二聚体水平大于心绞痛组（P〈0.01）;D-二聚体界值250μg/L鉴别诊断AAD的敏感度和阴性预测值均达到100%,随着D-二聚体水平的升高,诊断AAD的敏感性降低,特异性升高;低于500μg/L值能很好区分排除AAD,阴性预测值97.97%,对应阴性似然比0.02;在急性胸痛患者区分AAD诊断最佳临界点为982.5μg/L,受试者工作曲线下面积为0.972±0.010（95%CI,0.953 0.991）。结论：D-二聚体可作为急性胸痛患者中鉴别诊断主动脉夹层的方便指标。

The early diagnostic value of plasma D dimer in acute aortic dissection

Objective：To investigate the early diagnostic value of plasma D-dimer level in acute aortic dissection.Method：In this retrospective study,a total of 285cases with acute chest pain within 24hours from May 2011 to August 2013in our hospital were enrolled in the study.The D-dimer test was performed in all patients within 24 hours after onset of chest pain,D-dimer levels were compared between different groups divided by final diagnosis. The statistical analysis of data was carried out by SPSS 16.0.Kruskal Wallis H test was used to compare the median dimmers.Nemenyi methods were used for further comparisons.As analytical methods of diagnostic performance,sensitivity,specificity,likelihood ratios,and predictive values at designated cutoff levels and receiver-operating characteristic curve analysis with area under the curve calculations were done（P〈0.05was considered statistically significance）.Result：D-dimer was markedly elevated in patients with acute aortic dissection（AAD）and acute pulmonary embolism（APE）compared with acute myocardial infarction（AMI）,angina pectoris,acute pericarditis,acute pleurisy and other unknown diagnosis,as in acute myocardial infarction compared with angina pectoris（P〈0. 01）.For AAD patients,the cutoff level of D-dimer 250μg/L had a sensitivity of 100%,and negative PV 100%for ruling out acute aortic dissection.With the increase of D-dimer level,the sensitivity lower,and the specificity rise. At cutoff level of D-dimer 500μg/L had a specificity of 97.97%,and a negative likelihood of 0.02for identifying AAD.Receiver operating characteristic curve analysis for AAD versus all control subjects showed a best cutoff lever at 982.5μg/L,areas under the curve of 0.972±0.010（95%CI,0.953 0.991）.Conclusion：D-dimer may be a valuable biomarker in early differential diagnosis of acute chest pain.