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。     

主动脉夹层风险评分联合D-二聚体在主动脉夹层诊断中的应用价值

目的探讨主动脉夹层风险评分联合D-二聚体对于诊断主动脉夹层(AAD)的应用价值。方法收集近5年我科收治的怀疑急性主动脉夹层而行主动脉CT造影的病例共387例,根据最终诊断分为急性主动脉综合征(AAS)组和非AAS组。分析其临床资料,计算主动脉夹层风险评分(ADD-RS),并分析D-二聚体水平(243ng/mL为阳性)。结果AAS共161例,包括主动脉夹层AAD 151例(93.79%),壁间血肿5例(3.11%),主动脉溃疡3例(1.86%),腹主动脉瘤破裂2例(1.24%)。AAD中Stanford A型占71例(47.02%),Stanford B型占80例(52.98%)。D-二聚体阳性诊断AAS的敏感性为90.7%,特异性为26.1%;而D-二聚体>5000ng/mL诊断AAS的敏感性为22.4%,特异性为95.1%。15例AAS患者D-二聚体<243ng/mL。在AAS组内,ADD-RS=0、ADD-RS=1及ADD-RS>1分别占4.97%(8/161)、78.88%(127/161)及16.15%(26/161)。ADD-RS1诊断ASS的敏感性为95.0%,特异性为35.0%。ADD-RS=0并D-二聚体阴性者为22例,均为非AAS组,表明ADD-RS=0联合D-二聚体阴性排除AAS的敏感性为100%。ADD-RS>1联合D二聚体>5000ng/mL诊断AAS的敏感性为100%。结论ADD-RS联合D-二聚体可以极大提高临床排除或诊断AAD的准确性。     

D-二聚体在急性主动脉夹层中的诊断价值

目的 探讨血浆D-二聚体水平在急性主动脉夹层(acute aortic dissection,AAD)早期诊断中的价值.方法 选取2006年1月至2009年3月因胸痛就诊于复旦大学中山医院患者共80例,其中40例经动脉三维CT血管成像(CTA)检查确诊为急性主动脉夹层病例作为ADD组,同期以类似症状就诊但最终排除急性主动脉夹层的40例为对照组,所有患者胸痛发生12 h内检测血浆 D-二聚体,比较ADD组与对照组血浆 D-二聚体水平,分析D-二聚体诊断急性主动脉夹层的敏感性、特异性、阳性预测值、阴性预测值,并绘制D-二聚体诊断急性主动脉夹层的受试者工作曲线(receiver operating char-acteristic curve,ROC曲线).所有数据用SPSS 11.5统计软件分析处理,计量资料采用均数±标准差(χ±s)表示,两组间均数比较采用Mann-Whitney检验,以P<0.05为差异具有统计学意义.结果 ADD组血浆在D-二聚体水平明显高于对照组[(5.48±7.95)vs.(0.64±0.75),P<0.01];D-二聚体(>0.5 μg/mL)诊断急性主动脉夹层的敏感性、特异性、阳性预测值和阴性预测值分别为87.5%,62.5%,70%和83.3%,受试者工作曲线下面积为0.848±0.042,95%CI为0.766-0.930.结论 D-二聚体可作为急性主动脉夹层早期诊断有效的筛选指标.     

血浆D-二聚体水平对急性主动脉夹层的诊断价值探讨

目的探讨血浆D-二聚体水平对主动脉夹层早期诊断、病变程度预测和预后判断的价值。方法顾分析天津市第五中心医院2005-2-2008-8就诊的66例主动脉夹层（AAD）患者（男51例,女15例）,与同期就诊的急性冠脉综合症（ACS）患者（78例,男66例,女12例）作为对照,比较两组间包括D二聚体、C反应蛋白、肌钙蛋白I水平在内的各项临床常用指标的差异,分析D-二聚体在不同类型患者中的临床意义及病死相关性。结果急性主动脉夹层形成后D-二聚体水平显著升高,且D-二聚体水平与病变范围呈正相关（r=0．412,P〈0．01）,死亡患者D-二聚体水平显著高于存活患者（P=0．001）。结论D-二聚体是AAD患者的早期生物标志,D-二聚体的水平阴性有助于排除急性主动脉夹层的诊断,该检测指标对判断病变范围和预后有一定的指导价值。     

Accuracy of emergency medicine ultrasound in the evaluation of abdominal aortic aneurysm

This study assesses the accuracy of Emergency Medicine (EM) residents in detecting the size and presence of abdominal aortic aneurysms (AAAs) using EM ultrasound (EUS) compared to radiology measurement (RAD) by computed tomography (CT) scan, magnetic resonance imaging (MRI), angiography, or operative findings. There were 238 aortic EUS performed from 1999–2000; 36 were positive for AAA. The EUS finding of “AAA” had a sensitivity of 0.94 (0.86–1.0 95% confidence interval [CI]) and specificity of 1 (0.98–1.0 95% CI). Mean aortic diameter among patients with AAA identified by EUS was 5.43 ± 1.95 cm and by RAD was 5.35 ± 1.83 cm. The mean absolute difference between EUS and RAD diameters was 4.4 mm (95% CI 3.7–5.5 mm). Regression of EUS on RAD diameters is strongly correlated, with R² = 0.92. EM residents with appropriate training can accurately determine the presence of AAA as well as the maximal aortic diameter.     

Aortic dissection: review of value and limitations of two-dimensional echocardiography in a six-year experience

The utility of transthoracic two-dimensional echocardiography in patients with aortic dissection was assessed by retrospective analysis in 67 patients: 31 patients with DeBakey type I, 21 patients with type II, 10 patients with type III, and five patients with false-positive diagnoses. Aortic dissection was correctly identified by two-dimensional echocardiography in 49 patients; 13 had false-negative diagnoses. Therefore the sensitivity was 79%, and the positive predictive accuracy was 91%. Transthoracic two-dimensional echocardiography is a reasonable screening technique for diagnosis of aortic dissection.     

D-二聚体在主动脉夹层中的临床意义

目的:通过检测不同类型、病期和预后主动脉夹层(AD)患者血中D-二聚体浓度,探讨D-二聚体对AD的临床意义。方法:回顾性分析45例AD患者的临床资料。结果:主动脉夹层形成后D-二聚体均升高,均值为866.1±430ug/L。D-二聚体水平在急性期显著高于慢性期(P<0.01),DⅠ型明显高于DⅢ型(P<0.01)。死亡患者D-二聚体水平显著高于存活者。结论:D-二聚体水平有助于不同病期、不同类型AD的诊断,对鉴别诊断、判断病变范围及预后有一定指导意义。     

Combining clinical risk with D-dimer testing to rule out deep vein thrombosis

We sought to determine whether the combination of low-intermediate clinical risk of acute lower extremity deep vein thrombosis (DVT) and negative ELISA D-dimer assay can eliminate the need for duplex ultrasonography. Three hundred thirty-six patients prospectively underwent clinical risk stratification (low, intermediate, and high), D-dimer testing, and duplex ultrasonography. Thirteen of 145 intermediate-risk patients had acute DVT; 11 (85%) had a positive D-dimer. Two of 118 low-risk patients had acute DVT; both had a positive D-dimer. Intermediate-high risk stratification alone had sensitivity of 93.9% (95% CI: 80.3-98.3%) and a NPV of 98.3% (95% CI: 94.0-99.5%) for acute DVT. For all patients, a positive D-dimer alone had a sensitivity of 93.9% (95% CI: 80.3-98.3%) and a NPV of 98.6% (95% CI: 95.1-99.6%). The combination of D-dimer and intermediate-high risk classification had a sensitivity of 100% (95% CI: 89.4-100%) and a NPV of 100% (95% CI: 98.9-100%). In suspected acute lower extremity DVT, the combination of intermediate-high clinical risk and positive D-dimer has a high sensitivity and NPV, possibly eliminating the need for duplex ultrasound in this group of patients.     

Sensitivity and specificity of the semiquantitative latex agglutination D-dimer assay for the diagnosis of acute pulmonary embolism as defined by computed tomographic angiography

OBJECTIVE: To determine the sensitivity and specificity of the semiquantitative latex agglutination plasma fibrin D-dimer assay for the diagnosis of acute pulmonary embolism by using computed tomographic (CT) angiography as the diagnostic reference standard. PATIENTS AND METHODS: From January 1, 1998, to June 26, 2000, patients who had both semiquantitative latex agglutination plasma fibrin D-dimer testing and CT angiography for suspected acute pulmonary embolism were selected for the study. A D-dimer value greater than 250 ng/mL was considered positive for thromboembolic disease. Diagnosis of acute pulmonary embolism was based solely on the interpretation of the CT angiogram. The D-dimer assay results were then compared with the CT angiographic diagnoses. RESULTS: Of 946 CT studies, 172 (18%) were positive for acute pulmonary embolism. The D-dimer assay was positive for 612 (65%) of the 946 patients. For acute pulmonary embolism, the D-dimer assay had a sensitivity of 0.83 (95% confidence interval [CI], 0.76-0.88), a specificity of 039 (95% CI, 036-0.43), a negative likelihood ratio of 0.44 (95 % CI, 032-0.62), and a negative predictive value of 0.91 (95% CI, 0.87-0.94). CONCLUSIONS: The semiquantitative latex agglutination plasma fibrin D-dimer assay had moderate sensitivity and low specificity for the diagnosis of acute pulmonary embolism. When used alone, the results of this test were insufficient to exclude this serious and potentially fatal disorder. Approximately two thirds of our patients had positive D-dimer assays and required further evaluation to exclude acute pulmonary embolism.     

Evaluation of a quantitative D-dimer latex immunoassay for acute pulmonary embolism diagnosed by computed tomographic angiography

OBJECTIVE: To determine the sensitivity and specificity of a quantitative plasma fibrin D-dimer latex immunoassay (LIA) for the diagnosis of acute pulmonary embolism. SUBJECTS AND METHODS: Study subjects were Mayo Clinic Rochester inpatients and outpatients with suspected acute pulmonary embolism; all had undergone quantitative D-dimer LIA testing and multidetector-row computed tomographic (CT) angiography between August 3, 2001, and November 10, 2003. Multidetector-row CT angiography was the diagnostic reference standard. RESULTS: Of 1355 CT studies, 208 (15%) were positive for acute pulmonary embolism. Median D-dimer levels were significantly higher for patients with acute pulmonary embolism (1425 ng/mL) than for patients without (500 ng/mL) (P<.001). The highest specificity that optimizes sensitivity for acute pulmonary embolism was achieved by using a discriminant value of 300 ng/mL, which yielded a sensitivity of 0.94 (95% confidence interval [CI], 0.89-0.97), a specificity of 0.27 (95% CI, 0.25-0.30), and a negative predictive value of 0.96 (95% CI, 0.93-0.98). CONCLUSION: The quantitative D-dimer LIA with a discriminant value of 300 ng/mL had high sensitivity and high negative predictive value but low specificity for the diagnosis of acute pulmonary embolism. On the basis of these results, we believe that a negative quantitative D-dimer LIA result and a low pretest probability of thromboembolism together are sufficient to exclude acute pulmonary embolism.     

Review article: Accuracy of emergency physician performed point-of-care ultrasound of the thoracic aorta: A systematic review and narrative synthesis of the literature

Point-of-care ultrasound (POCUS) is becoming ubiquitous in emergency medicine. POCUS for abdominal aortic aneurysm is well established in practice. The thoracic aorta can also be assessed by POCUS for dissection and aneurysm and transthoracic echocardiography is endorsed by international guidelines as an initial test for thoracic aortic pathologies. A systematic search of Ovid Medline, PubMed, EMBASE, SCOPUS and Web of Science from January 2000 to August 2022 identified four studies evaluating diagnostic accuracy of emergency physician POCUS for thoracic aortic dissection (TAD) and five studies for thoracic aortic aneurysm (TAA). Study designs were heterogeneous including differing diagnostic criteria for aortic pathology. Convenience recruitment was frequent in prospective studies. Sensitivity and specificity ranges for studies of TAD were 41–91% and 94–100%, respectively when an intimal flap was seen. Sensitivity and specificity ranges for studies of thoracic aorta dilation >40 mm were 50–100% and 93–100%, respectively; for >45 mm ranges were 64–65% and 95–99%. Literature review identified that POCUS is specific for TAD and TAA. POCUS reduces the time to diagnosis of thoracic aortic pathology; however, it remains insensitive and cannot be recommended as a stand-alone rule-out test. We suggest that detection of thoracic aorta dilation >40 mm by POCUS at any site increases the suspicion of serious aortic pathology. Studies incorporating algorithmic use of POCUS, Aortic Dissection Detection Risk Score and D-dimer as decision tools are promising and may improve current ED practices. Further research is warranted in this rapidly evolving field.     

探讨性别对健康成人和主动脉夹层患者血浆D-二聚体浓度的影响

目的探讨性别对健康成人和主动脉夹层患者D-二聚体浓度的影响。方法 2015年1月至2016年1月该院收治主动脉夹层患者53例,另选年龄相匹配的健康对照组50例,用Sysmex CS5100检测入选人群的D-二聚体浓度,并进行统计学分析。结果相同年龄区间内,健康对照组女性D-二聚体浓度高于男性,差异有统计学意义(t=5.357,P0.05);主动脉夹层组男性D-二聚体浓度明显高于同龄女性,差异有统计学意义(t=-2.041,P0.05);主动脉夹层组D-二聚体浓度高于健康对照组,差异有统计学意义(t=5.757,P0.05)。结论 D-二聚体浓度在健康成人和主动脉夹层患者之间有性别差异,且具有一定相关性。     

Investigation of age-adjusted D-dimer using an uncommon assay

BackgroundUse of an age-adjusted D-dimer for the evaluation of acute pulmonary embolus (PE) has been prospectively validated in the literature and has become a practice recommendation from major medical societies. Most research on this subject involves the most common D-dimer assays reporting in Fibrinogen Equivalent Units (FEU) with a non-age-adjusted manufacturer-recommended cutoff of 500 ng/ml FEU. Limited research to date has evaluated age-adjustment in assays that report in D-Dimer Units (D-DU), which use a manufacturer-recommended cutoff of 230 ng/ml D-DU. Despite scant evidence, an age-adjusted formula using D-DU has been recently endorsed by the American College of Emergency Physicians (ACEP). This formula seems arbitrary in its derivation and unnecessarily deviates from existing thresholds, thus prompting the creation of our novel-age adjustment formula. The goal of this study was to retrospectively evaluate the test characteristics of our novel age-adjusted D-dimer formula using the D-DU assay in comparison to existing traditional and age-adjusted D-dimer thresholds for the evaluation of acute PE in the ED.MethodsThis was a retrospective chart review at an academic quaternary health system with three EDs and 195,000 combined annual ED visits. Only patients with D-dimer testing and CT PE protocol (CTPE) imaging were included. Admission and discharge diagnosis codes were used to identify acute PE. Outcome measures were sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of an unadjusted traditional threshold (230) compared with both novel and ACEP-endorsed age adjusted thresholds, (Age × 5) ? 20 and Age × 5 if >50, respectively. Estimates with their exact 95% threshold were performed.Results4846 adult patients were evaluated from January 2012 to July 2017. Group characteristics include a mean age of 52 and a frequency of acute PE diagnosis by CTPE of 8.25%. Traditional D-dimer cutoff demonstrated a sensitivity of 99.8% (95% CI 98.6–100), specificity of 16.7% (95% CI 15.6–17.8) and NPV of 99.9% (95% CI 99.3–100). Our novel age-adjusted D-dimer thresholds had a sensitivity of 97.0% (95% CI 94.8–98.4), specificity of 27.9% (95% CI 26.6–29.2) and NPV of 99.0% (95% CI 98.3–99.5) with the ACEP-endorsed formula demonstrating similar test characteristics.ConclusionUse of an age-adjusted D-dimer on appropriately selected patients being evaluated for acute PE in the ED with a D-DU assay increases specificity while maintaining a high sensitivity and NPV. Both our novel formula and the ACEP-endorsed age-adjusted formula performed well, with our novel formula showing a trend towards improved testing characteristics.     

Diagnostic accuracy of biomarker D-dimer in patients after stroke suspected from venous thromboembolism: A diagnostic meta-analysis

D-dimer is a promising biomarker for identification of venous thromboembolism (VTE) in patients with stroke. The purpose of our study is to evaluate the diagnostic value of D-dimer as a promising biomarker for VTE in patients after stroke. We performed an exhaustive search of leading databases including Pubmed, Embase, the Cochrane library, China National Knowledge Infrastructure (CNKI), and China Biology Medicine disc (CBM) from inception to Oct 13, 2017. We included studies written in English and Chinese. We included studies that appraised the diagnostic value of D-dimer with reference standard for VTE diagnosis in patients after stroke. We concurrently constructed a 2 × 2 table with data extracted from included studies. We identified 8 studies that included 1490 patients after stroke from our database searches. The pooled result from limited evidence showed a sensitivity of 0.85 (95% CI 0.76–0.90) and a specificity of 0.77 (95% CI 0.73–0.81). The area under the summary receiver operating characteristic curve was 0.85(95% CI 0.81–0.88). The positive likelihood ratio (LR+) and the negative likelihood ratio (LR-) were 3.8 (95% CI 3.1–4.4) and 0.20(95% CI 0.12–0.31), respectively. In patients after stroke suspected of venous thromboembolism, D-dimer is a beneficial biomarker for diagnosis of VTE. For stroke patients with low probability of VTE, a normal D-dimer test can be used to rule-out VTE. However, we do not recommend using D-dimer as the single definitive test for VTE diagnosis. We recommend diagnosing VTE using multi-branch diagnostic strategy.     

Prevalence of acute myocardial infarction and other serious diagnoses in patients presenting to an urban emergency department with chest pain

A retrospective cohort study and chart review were performed to estimate the absolute and relative prevalence of the serious diagnoses that might cause a patient to present to the Emergency Department (ED) with a chief complaint of chest pain. In this study, we queried a database of 347,229 complete visits to the San Francisco General Hospital Emergency Department between July 1, 1993 and June 30, 1998 for visits by patients > 35 years old with a chief complaint of chest pain and no history of trauma. Visits for chest pain that resulted in hospitalization were assigned to one of nine diagnostic groups according to final diagnoses as coded in the database. Manual chart review by trained abstractors using explicit criteria was done when group assignment based on coded diagnoses was unclear and in all diagnoses of pulmonary embolism and aortic dissection. Of 8711 visits (2.5% of all visits) with a chief complaint of non-traumatic chest pain, 3271 (37.6%) resulted in hospitalization. Of the 3078 (94.1% of those hospitalized) assigned a final diagnosis, 329 (10.7% of hospitalizations, 3.8% of all visits) had acute myocardial infarction, 693 (22.5%) had either unstable angina or stable coronary artery disease, and 345 (11.2%) had pulmonary causes (mainly bacterial pneumonia) deemed serious enough to require hospitalization. Pulmonary embolism and aortic dissection were diagnosed in only 12 (0.4%) and 8 (0.3%) patients, respectively. In 905 (29.4%) hospitalizations for chest pain, myocardial infarction was “ruled out” and no cardiac ischemia or other serious etiology for the chest pain was diagnosed. Among patients presenting with chest pain, those in older age groups had dramatically increased risk of acute myocardial infarction. Women presenting with chest pain had a lower risk of acute myocardial infarction than men. In conclusion, the prevalence of acute myocardial infarction in the undifferentiated ED patient with a chief complaint of chest pain is only about 4%. An equal number of patients will have a serious pulmonary cause as the etiology of their pain. Pulmonary embolism and aortic dissection are important but extremely rare causes of a chest pain presentation to the ED.     

血浆可溶性髓样细胞触发受体1对成人脓毒症患者诊断价值的Meta分析

目的评价血浆可溶性髓样细胞触发受体1（sTREM-1）对成人脓毒症患者的诊断价值。 方法检索PubMed、Embase、Cochrane图书馆、中国生物医学文献数据库（CBM）、中国期刊全文数据库（CNKI）、万方数据库和中文科技期刊全文库（VIP）数据库从建库至2017年5月发表的有关血浆sTREM-1对成人脓毒症患者诊断价值的文献。采用双变量模型计算合并诊断比值比（DOR）、合并敏感度、合并特异度、合并阳性似然比（PLR）及合并阴性似然比（NLR）。进行合并受试者工作特征（SROC）曲线，获得曲线下面积（AUC）。 结果最终纳入30篇文献，共3 349例患者。Meta分析显示，合并DOR为20.03[95%置信区间（CI）（12.20，32.87）]、合并敏感度为0.82[95% CI（0.77，0.86）]、合并特异度为0.81 [95% CI（0.76，0.85）]、合并PLR为4.36 [95% CI（3.37，5.64）]、合并NLR为0.22[95%CI（0.16，0.29）]。SROC曲线显示合并AUC为0.89[95%CI（0.85，0.91）]。 结论血浆sTREM-1对诊断成人脓毒症患者具有中度诊断价值。     

血清D-二聚体在急性主动脉夹层诊断中的意义

目的探讨血清D-二聚体（D-dimer）水平在急性主动脉夹层诊断和预后判断中的价值。方法分析近5年来收治的34例急性主动脉夹层患者血清D-dimer水平,以同期36例急性心肌梗死患者作为对照,比较两组间的差异。分析主动脉夹层患者血清D-dimer水平与主动脉夹层不同分型及主动脉夹层死亡的相关性。结果主动脉夹层组患者血清D-dimer水平（7．1±1．7mg／L）明显高于急性心肌梗死组（0．7±0．3mg／L）（P〈0．01）。2例死亡患者D-dimer均高于10mg/L。结论主动脉夹层血清D-dimer显著升高,D-dimer水平有助于主动脉夹层诊断和预后判断。     

下壁导联 ST 段抬高急性主动脉夹层临床分析

目的：分析下壁导联 ST 段抬高的急性主动脉夹层临床特征，减少误诊，及时采取正确治疗策略。方法回顾性分析14例下壁导联 ST 段抬高的急性主动脉夹层临床表现、心电图特点、影像学表现、实验室检查、冠脉造影表现和治疗转归等资料。结果下壁导联 ST 段抬高的急性主动脉夹层患者相关临床表现提示单一高血压危险因素占79％，就诊时血压正常或高血压比例为86％；心电图提示 ST 段抬高幅度 STⅢ＞STⅡ并伴 V1或 V4R 导联 ST 段抬高比例为86％；实验室检查提示平均 D-二聚体＞2000 ng／mL；冠脉造影表现为未显示冠脉开口、冠脉血管正常或单纯右冠近端病变等；经胸心脏超声和胸部 CT 大血管造影对本病的识别率达到100％；本组患者的病死率为50％。结论下壁导联 ST 段抬高的急性主动脉夹层患者病情危重，病死率高，急诊手术治疗能明显提高患者生存率。     

血浆D-二聚体对疑似肺栓塞患者诊断价值的研究

目的：探讨血浆 D-二聚体对对疑似肺栓塞患者的诊断价值。方法采用自动化免疫比浊法测定患者血浆D-二聚体水平。统计分析血浆D-二聚体诊断肺栓塞的敏感性、特异性、阴性及阳性预测值,并绘制ROC曲线以评价其诊断价值并对D-二聚体阴性排除肺栓塞价值进行分析。结果在317例疑似肺栓塞患者中D-二聚体＜500μg/L的患者73例,其中6例被诊断为肺栓塞。D-二聚体对肺栓塞的诊断的敏感性为95.86%（95%CI：91.27%～98.08%）,特异性为38.95%（95%CI：31.98%～41.41%）,阴性预测值为91.78%（95%CI：83.21%～96.18%）,阳性预测值为56.97%（95%CI：50.69%～63.02%）,诊断准确性为64.98%（95%CI：59.58%～70.03%）。ROC曲线下面积为0.674（95%CI：0.615～0.733）。结论 D-二聚体对肺栓塞的诊断具有较高的敏感性,阴性排除肺栓塞的准确性较高,但仍可受患者年龄、测试方法等的影响。     

Aortic dissection: a dreaded disease with many faces

Aortic dissection is a relatively uncommon but catastrophic illness classically thought to present with acute, sharp, chest pain with radiation to the back. However, aortic dissection can manifest in a number of different ways that include congestive heart failure, inferior myocardial infarction, stroke, focal pulse and neurologic deficits, abdominal pain, or acute renal failure. According to some studies, only about 80% of patients with type A dissection present with severe anterior chest pain, and only about 60% describe their pain as being sharp. Another series reports that treating clinicians fail to initially entertain the diagnosis of aortic dissection in up to 35% of cases. Many patients later found to have aortic dissection are initially suspected to have other conditions such as acute coronary syndrome, pericarditis, pulmonary embolism, or even cholecystitis. In this article we present a case of an unusual presentation of aortic dissection and a review of this condition.