CBO guideline 'Deep venous thrombosis and pulmonary embolism; revision of the earlier guidelines. Dutch Organization for Quality Assurance in Hospitals

Diagnosis of clinically suspected deep venous thrombosis is based on a clinical score, serial compression ultrasonography and D-dimer assay. For the diagnosis of pulmonary embolism perfusion scintigraphy, ventilation scintigraphy, echography of the leg veins and pulmonary angiography in that order lead to the lowest mortality, morbidity and costs. Diagnostics with spiral CT followed by pulmonary angiography leads to equal mortality and fewer angiography procedures. Decision rules based on anamnesis, physical examination, blood gas analysis and chest radiograph have proved to be insufficiently reliable. The present D-dimer assays have too little sensitivity and too much variability. Thrombo-prophylaxis with low-molecular-weight heparin is indicated for general surgery, joint replacement of the knee or hip, cranial and spinal surgery, subarachnoid haemorrhage after surgical treatment of an aneurysm, acute myocardial infarction, ischaemic stroke or spinal cord lesion, intensive care patients, patients with acute paralysis due to a neuromuscular disorder, and bedridden patients with a risk factor. Prophylaxis has to be continued as long as the indication exists. In the acute phase of deep venous thrombosis or pulmonary embolism treatment with (low-molecular-weight) heparin in an adequate dose is necessary. When started at the same time as coumarin derivatives the treatment with heparin has to be continued for at least 5 days. The risk of postthrombotic syndrome after deep venous thrombosis will be lowered by carrying compression stockings for at least 2 years after the event.     

64层螺旋CT血管造影诊断中度疑似肺栓塞的临床价值

目的探讨肺通气灌注显像和CT肺动脉造影2种无创性检查技术诊断肺栓塞（PE）,对临床Wells评分分组为中度疑似肺栓塞的诊断价值。方法 将2006年3月至2009年11月,临床Wells评分分组为中度疑似肺栓塞60例患者,行64层螺旋CT肺动脉造影和肺通气/灌注显像,对2种显像的判定结果进行相关分析,其准确性、符合性及不确定性诊断比率的差异采用χ2检验进行比较。结果 Wells评分为中度可能组中CTPA和V/Q显像诊断PE的敏感性、特异性、符合率分别为：88%、72%、P〈0.01;91%、77%、P〈0.01;90%、74%、P〈0.01。结论在Wells评分中度可能性组别中,CTPA诊断PE均较V/Q显像的价值高,并可作为临床中度疑诊肺栓塞病例的首选检查方法。     

Negative ELISA D-dimer assay can miss pulmonary embolism

This evaluation of the use of enzyme-linked immunosorbent assay (ELISA) D-dimer test in routine clinical practice supports other evidence that the assay has a high sensitivity to exclude pulmonary embolism in patient populations in which there is clinical suspicion. Nevertheless, the assay incorrectly excluded the diagnosis of pulmonary embolism in 2 cases. Other examples of clinical decision-making exist for which the acceptable negative predictive value for screening is set at 100%--eg, the diagnosis of phenylketonuria in newborns. Physicians who do not want to miss cases of acute pulmonary embolism when they clinically suspect the diagnosis should not rely solely on negative D-dimer assay results when the value to rule out the diagnosis is set at 500 ng/mL. If a lower value is used to define normal--eg, 250 ng/mL, as used in other studies-no cases of acute pulmonary embolism would have been missed in this group of patients. Regardless of the cutoff used, the assay will yield many false-positive results.     

The cost-effectiveness of diagnostic strategies in patients with suspected pulmonary embolism

The cost-effectiveness of various diagnostic strategies in patients with clinically suspected pulmonary embolism (PE) was analysed using a modelling approach. In 451 consecutive patients with clinically suspected PE data on the performance of diagnostic tests were collected prospectively in two large teaching hospitals in Amsterdam, The Netherlands. The ventilation-perfusion lung scan was used as the primary diagnostic test in all patients. In patients with a non-diagnostic lung scan result the performance of a clinical decision rule, a D-dimer test, and ultrasonography of the leg veins was evaluated with pulmonary angiography as the gold standard. It was estimated that the strategy recommended by a 1992 Dutch consensus meeting costs about Dfl 4400 per patient and that 97.02% of the patients can be expected to survive the first 6 months after the primary PE. The nation-wide annual costs for the diagnosis and treatment of patients by this strategy were estimated at 163 million Dutch Guilders. Subsequently, the costs and effects of alternative strategies were evaluated in a modelling approach, and compared with those of the consensus strategy. One strategy was selected that produces the best results in terms of survival and leads to considerable savings as compared with the consensus strategy. In this strategy subsequently a ventilation-perfusion scan, a clinical decision rule, a D-dimer test, a pulmonary angiography and leg ultrasonography are performed. Patients with a high probability ventilation-perfusion scan, an abnormal angiography or leg ultrasound test are treated, whereas treatment is withheld in patients with a normal ventilation-perfusion scan, a normal clinical decision rule, a negative D-dimer test, a normal angiography, or a normal leg ultrasound test. This strategy will have to prove its value and usefulness in clinical practice in a subsequent prospective validation phase.     

肺癌合并肺动脉栓塞症的CTA表现

探讨肺癌患者合并肺动脉栓塞（PE）的临床表现及CT血管成像（CTA）特点,提高对肺癌并发肺动脉栓塞的防治认识,并研究两者在临床上诊断上的相关性。方法：回顾性分析763例原发性肺癌患者的临床及影像资料,9例确诊肺动脉栓塞,同时分析其诊断及治疗相关性。结果：肺癌患者急性肺动脉栓塞的发生率约1.2%（9/763）。9例患者均静脉应用肝素和口服华法林抗凝治疗,其中2例采用了尿激酶溶栓治疗,经积极溶栓及抗凝治疗后效果良好。结论：重视肺癌合并肺栓塞的及早期诊断与治疗,CTA对肺血栓栓塞症的诊断简便、安全、准确率高,敏感性和特异性较高,是诊断肺癌合并肺动脉栓塞症的理想检查方法。     

多层螺旋CT扫描诊断肺动脉栓塞的应用价值

目的：探讨肺动脉栓塞患者的CT影像诊断价值。方法：回顾性分析22例临床怀疑为肺动脉栓塞的患者利用16排螺旋CT行肺动脉成像检查的影像学资料。结果：22例患者的肺动脉栓塞部位及范围均能显示,其中肺动脉栓塞10例,肺叶动脉栓塞7例,肺段及段以下动脉栓塞5例。22例患者中只有4例为单支动脉栓塞。结论：多层螺旋CT肺动脉成像作为一种无创性检查方法,能为肺动脉栓塞诊断提供直接、丰富的影像诊断细节,并能在治疗后较好地评价溶栓效果。     

Screening for pulmonary embolism with a D-dimer assay: do we still need to assess clinical probability as well?

Clinical risk stratification and D-dimer assay can be of use in excluding pulmonary embolism in patients presenting to emergency departments but many D-dimer assays exist and their accuracy varies. We used clinical risk stratification combined with a quantitative latex-agglutination D-dimer assay to screen patients before arranging further imaging if required. Retrospective analysis of a sequential series of 376 patients revealed that no patient with a D-dimer of <275 ng/mL was diagnosed with pulmonary embolism, irrespective of clinical probability. We conclude that a latex-agglutination assay could be used to exclude pulmonary embolism without the necessity for clinical risk stratification. If these findings are borne out by further work, D-dimer strategies to exclude pulmonary embolism could substantially reduce imaging workload.     

血清DD、CRP、BNP联合Wells评分诊断肺栓塞患者的临床价值分析

目的探讨血清D-二聚体(DD)、C反应蛋白(CRP)、B型脑钠肽(BNP)联合Wells评分诊断肺栓塞患者的临床价值。方法选取90例肺栓塞患者作为研究组,选取同期90例健康体检者作为对照组,均进行血清DD、CRP、BNP检测和Wells评分,比较两组的血清DD、CRP、BNP水平及Wells评分,分析血清DD、CRP、BNP联合Wells评分诊断肺栓塞的效果及相关性。结果研究组的血清DD、CRP、BNP水平及Wells评分均显著高于对照组(P<0.05)。血清DD、CRP、BNP水平及Wells评分越高,诊断肺栓塞的可能性越大,呈现正相关(P<0.05)。血清DD、CRP、BNP联合Wells评分诊断肺栓塞的灵敏度、特异度、准确度均显著高于血清DD、CRP、BNP水平及Wells评分单一诊断(P<0.05)。结论血清DD、CRP、BNP联合Wells评分诊断肺栓塞的效能更高,对于早期肺栓塞患者的筛查与诊断具有重要的临床意义。     

CTPA in suspected pulmonary embolism: diagnostic strategy

De Bruin and colleagues recently analysed the performance of the CTPA scan in patients with suspected pulmonary embolism. Their study shows that in a significant number of patients no abnormalities were found on a CTPA scan, a troubling finding given the radiation exposure. Young patients and ambulatory patients, in particular, often had a completely normal CTPA scan. Better stratification of patients with a high suspicion of pulmonary embolism is required, including evaluation of the value of clinical decision rules in ambulatory patients with suspected pulmonary embolism. In addition, the use of perfusion scanning, which involves significantly less radiation exposure, deserves further research in young people. Principally, a diagnostic strategy for pulmonary embolism comprising a clinical decision rule, followed by a D-dimer test if necessary, should be applied in clinical practice. This strategy will significantly reduce the number of CTPA scans showing no pulmonary embolism.     

Acute massive pulmonary embolism

To establish the diagnosis of the acute massive pulmonary embolism is critically urgent for the doctors, because the life saving causal therapy should be introduced as soon as possible. The combined use of the estimated clinical probability and the results of one or more noninvasive examinations increase the accuracy in confirming the diagnosis of embolism. The most important methods to confirm or rule out the suspicion of pulmonary embolism are the noninvasive perfusion pulmonary isotopic scanning, spiral CT, echocardiography and the invasive "gold standard" pulmonary angiography. The life saving causal therapy means the urgent recanalization of the obstructed pulmonary arteries. The surgical embolectomy is a high risk intervention, but the invasive radiological methods are also capable of destroying the emboli mechanically and very effectively. The different thrombolytic treatment methods mean causal therapy too, and these protocols can be used in every hospital. There is no alternative treatment in patients with sudden clinical death caused by acute pulmonary embolism: the drug administration during reanimation should be completed with thrombolysis.     

Diagnosis of non-severe pulmonary embolism by a decision analysis-based strategy in pulmonary hospital recruted-patients

We have study prospectively cases of non severe pulmonary embolism in a pulmonary department by an analysis based strategy associating radio-clinical probability, venous ultra sonography, D-Dimers value followed, if no performed diagnosis, by pulmonary scintigraphy or angio-CT scan. 64 cases of pulmonary embolism suspicion have been hospitalised in our department between October 1998 and July 2001; 40 patients was included in our study and have been classified in 3 groups regarding pre test clinical probability. Anticoagulant treatment has been initialised only in the third group (probability >80%) Clinical probability associated with venous ultra sonography and D- Dimeres value allow or exclude pulmonary embolism diagnosis in 27 patients. In the others, scintigraphy and angio CT scan were necessary for establishing diagnosis. Application of this algorithm allow diagnosis of pulmonary embolism in 29 patients and exclude this pathology in the other 11. None of this patient complained from recurrent thrombo embolic accident during 17 to 42 months observance period.     

Pulmonary embolism: optimizing the diagnostic imaging approach

Venous thromboembolism is a common medical problem that can affect a wide range of patients. The clinical presentation ranges from minor, nonspecific signs and symptoms to severe clinical scenarios. The combination of objective pretest clinical probability, D-dimer testing, and imaging studies plays a critical role in its diagnosis. There are multiple imaging modalities to confirm or exclude the presence of pulmonary embolism and deep vein thrombosis, but, at present, computed tomography angiography is the most frequently used. Other imaging, however, is required for several subpopulations.     

2 patients with signs of venous thromboemolism: deviations from the guidelines

Deviations from the relevant guidelines occurred during the diagnosis of 2 patients with clinical signs of venous thromboembolism (VTE). In a 73-year-old man with bladder cancer and dyspnoea in whom pulmonary embolism was suspected, pulmonary angiography was not performed following a negative ventilation/perfusion scan; instead, a less invasive spiral CT scan was performed. Because the communicated outcome of 'pulmonary embolism' was incorrect, the patient was treated with anticoagulants and began bleeding from a duodenal ulcer. In a 32-year-old man with minor clinical signs of deep-vein thrombosis in his right leg, additional investigation was not pursued following negative echography. After 3 weeks, the thrombosis was extensive and pulmonary embolism developed, and it appeared that there was a family history of VTE. Both patients were later adequately diagnosed and treated. Guidelines are increasingly used in legal matters as a gauge in the assessment of medical care. Physicians and hospital directors are responsible for a policy on guidelines and the (possible) compliance therewith. Physicians should and must deviate from guidelines if there are good reasons. They must justify the deviation from protocol in the medical records.     

急性肺栓塞致右心室功能不全的CT影像学分析

目的本研究旨在探讨急性肺栓塞(APE)致右心功能不全(RVD)患者CT影像学变化及其意义。方法回顾性分析解放军总医院2016年1月~12月经CT肺血管造影(CTPA)证实为肺栓塞并行右心导管检查确诊右心功能不全的患者26例为研究组,同时选取同期入院经CTPA排除的疑诊APE患者62例作为对照组,分析肺栓塞致右心功能不全患者CT影像学变化及其意义。结果研究组CTPA测量的RVd/LVd、冠状静脉窦直径明显大于对照组,差异有统计学意义(P0.05)。结论在肺栓塞患者的临床诊断中,采用CTPA检查方式,同时测量RVd/LVd、冠状静脉窦直径,有助于在诊断肺栓塞的同时判断患者是否存在右心功能不全,为患者临床治疗提供指导。     

Body Time

Abstract

Venous thromboembolism is a common medical problem that can affect a wide range of patients. The clinical presentation ranges from minor, nonspecific signs and symptoms to severe clinical scenarios. The combination of objective pretest clinical probability, D-dimer testing, and imaging studies plays a critical role in its diagnosis. There are multiple imaging modalities to confirm or exclude the presence of pulmonary embolism and deep vein thrombosis, but, at present, computed tomography angiography is the most frequently used. Other imaging, however, is required for several subpopulations.     

急性肺动脉栓塞的CT肺动脉造影和MR诊断的对比研究

目的：探讨急性肺动脉栓塞（PE）的多层螺旋CT肺动脉造影（MSCTPA）和MR肺动脉成像（MRPA）的诊断价值并进行对比。方法：选取2012年9月-2013年10月本院收治并拟诊为PE的患者52例,根据患者采用的成像方法分为CT组（n=41）和MR组（n=11）,CT组患者行MSCTPA,MR组患者行1.5T MRPA,均观察肺动脉栓子的特点和肺叶继发变化情况,并由2位不知情的高级职称影像科医师对两组图像进行分析,统计不同部位的急性肺动脉栓塞检出数量。结果：CT组患者中,MSCTPA共发现肺动脉栓子661支,包括488支中段以上栓子。MR组患者中,MRPA共发现31支肺动脉栓塞。结论：MSCTPA操作简单,快捷,可清楚地显示肺动脉栓子,检出率高;MRPA可清楚显示肺叶动脉以上的栓子,但肺段动脉栓子仅部分可显示清楚,可结合三维增强磁共振动脉成像（3D-CE-MRPA）进行诊断。     

多层螺旋CT肺动脉血管造影检查在诊断肺动脉血管栓塞中的临床应用价值及进展展望

近年来,临床上肺动脉血管栓塞(PE)的发病率日益增加。随着医学技术的飞速发展,尤其是新的诊疗方法的普及,临床诊断与影像放射学诊断能力都得到很大的提高,PE的临床确诊病例增加非常明显,也为临床制定及时有效的救治方法,提供了有力的依据。目前PE已成为医学影像学科和相关临床学科的重点研究课题之一,但由于多数患者缺乏敏感性和特异性的临床表现和实验室检查数据,故PE的临床诊断主要依赖于医学影像学检查。本文就多层螺旋CT肺动脉血管造影应用诊断及其进展展望做一系统综述。     

The role of spiral computed tomography and D-dimer in pulmonary embolism

The first part of this study retrospectively compared the discriminatory power of spiral CT versus clinical findings in 112 consecutive patients referred with chest pain or dyspnoea. Spiral CT exhibited a sensitivity 91.9%; specificity 98.7%; PPV 97.1%; NPV 96.1%; accuracy 96.4%. No other test or clinical parameter had acceptable accuracy. The SimpliRED test is a latex method of estimating the level of D-dimer. The second part of this study determined that, in a similar consecutive series of patients referred for lung scintigrams, although SimpliRED tests had a NPV 95.5%, 59/126 (46.8%) consecutive were positive. However on the basis of clinical effectiveness and cost, imaging for suspected pulmonary embolism should be based on a combination of D-dimer estimation and spiral CT.     

Diagnostic work-up of severe diseases: simple prediction rules or just a simple test?

Diagnosing pulmonary embolism is an important problem. Several risk factors have been combined in prediction models, such as the Wells en Geneva scores. These models were prospectively validated in a large Dutch study (Prometheus study). With respect to this study, two critical issues are noted. Firstly, the discriminative ability of the models was modest, with areas under the Receiver Operating Characteristic (ROC) curve around 0.7. Secondly, the cut-offs to define low risk groups for the prediction rules were rather liberal, defining 60-70% of the included patients as 'low risk', while around 15% of these had a pulmonary embolism. In combination with a D-dimer test only 22-23% were classified as negative. This test missed only 1 patient among 186 patients identified with a pulmonary embolism. Performing a D-dimer test is hence essential in all patients in the selection for a CT scan. Improvements in the prediction rules are necessary to make these meaningful in the diagnostic work-up for pulmonary embolism.     

探讨多层螺旋CT在肺动脉栓塞中的临床应用

目的分析多层螺旋CT在肺动脉栓塞患者临床诊断中的应用价值。方法选取2010年1月—2013年12月期间我院收治的74例肺部动脉栓塞患者作为观察对象,所有患者均经16层CT配合MPB、MIP及VR进行高效处理进行诊断,回顾性分析本组患者的影像学情况。结果本组74例患者经多层螺旋CT检查后,本组74例患者中,病变共受累肺动脉485支,其中显示栓塞左/右肺动脉10支,亚段肺动脉207支,叶肺动脉117支,段肺动脉151支。结论多层螺旋CT在PE的临床诊断中具有无创、高效、准确率高等特点,尤其是对亚段PE的敏感性非常高,可以作为今后临床中关于PE的首选诊断方法。