Guidelines on the diagnosis and management of acute pulmonary embolism: the Task Force for the Diagnosis and Management of Acute Pulmonary Embolism of the European Society of Cardiology (ESC)

Outpatient versus inpatient treatment for patients with acute pulmonary embolism: an international, open-label, randomised, non-inferiority trial

BACKGROUND

Although practice guidelines recommend outpatient care for selected, haemodynamically stable patients with pulmonary embolism, most treatment is presently inpatient based. We aimed to assess non-inferiority of outpatient care compared with inpatient care.

METHODS

We undertook an open-label, randomised non-inferiority trial at 19 emergency departments in Switzerland, France, Belgium, and the USA. We randomly assigned patients with acute, symptomatic pulmonary embolism and a low risk of death (pulmonary embolism severity index risk classes I or II) with a computer-generated randomisation sequence (blocks of 2-4) in a 1:1 ratio to initial outpatient (ie, discharged from hospital ≤24 h after randomisation) or inpatient treatment with subcutaneous enoxaparin (≥5 days) followed by oral anticoagulation (≥90 days). The primary outcome was symptomatic, recurrent venous thromboembolism within 90 days; safety outcomes included major bleeding within 14 or 90 days and mortality within 90 days. We used a non-inferiority margin of 4% for a difference between inpatient and outpatient groups. We included all enrolled patients in the primary analysis, excluding those lost to follow-up. This trial is registered with ClinicalTrials.gov, number NCT00425542.

FINDINGS

Between February, 2007, and June, 2010, we enrolled 344 eligible patients. In the primary analysis, one (0·6%) of 171 outpatients developed recurrent venous thromboembolism within 90 days compared with none of 168 inpatients (95% upper confidence limit [UCL] 2·7%; p=0·011). Only one (0·6%) patient in each treatment group died within 90 days (95% UCL 2·1%; p=0·005), and two (1·2%) of 171 outpatients and no inpatients had major bleeding within 14 days (95% UCL 3·6%; p=0·031). By 90 days, three (1·8%) outpatients but no inpatients had developed major bleeding (95% UCL 4·5%; p=0·086). Mean length of stay was 0·5 days (SD 1·0) for outpatients and 3·9 days (SD 3·1) for inpatients.

INTERPRETATION

In selected low-risk patients with pulmonary embolism, outpatient care can safely and effectively be used in place of inpatient care.

FUNDING

Swiss National Science Foundation, Programme Hospitalier de Recherche Clinique, and the US National Heart, Lung, and Blood Institute. Sanofi-Aventis provided free drug supply in the participating European centres.

Usefulness of combined assessment with computed tomographic signs of right ventricular dysfunction and cardiac troponin T for risk stratification of acute pulmonary embolism

The aim of this study was to evaluate the incremental value of combined assessment with computed tomographic (CT) signs of right ventricular (RV) dysfunction and cardiac troponin T level for predicting early death or adverse outcomes due to acute pulmonary embolism (PE). One hundred seventy-three non-high-risk patients with acute PE, confirmed by CT pulmonary angiography, were retrospectively evaluated. The area under the curve and hazard ratio of CT signs and troponin T levels were compared for predicting early death or adverse outcomes. Patients were classified into intermediate- and low-risk groups on the basis of CT signs and troponin T levels, and mortality was compared. Seventeen patients (9.8%) died within 3 months. Early mortality of intermediate-risk patients (14% to 19%) was higher than that of low-risk patents (2% to 6%). A ratio of RV volume to left ventricular volume > 1.5 had the highest area under the curve (0.709) and hazard ratio (5.402) for predicting early death. The combination of CT signs and elevated troponin T level had an increased area under the curve and hazard ratio for predicting early death and adverse outcomes compared to those of CT signs or elevated troponin T level alone. In conclusion, the combined assessment of the ratio of RV volume to left ventricular volume and an elevated troponin T level provided incrementally more prognostic information in non-high-risk patients with acute PE compared to the single predictor of CT signs or troponin T level.

Does a clinical decision rule using D-dimer level improve the yield of pulmonary CT angiography?

OBJECTIVE

The objective of our study was to evaluate the impact of incorporating a mandatory clinical decision rule and selective d-dimer use on the yield of pulmonary CT angiography (CTA).

MATERIALS AND METHODS

Guidelines incorporating a clinical decision rule (Wells score: range, 0-12.5) and a highly sensitive d-dimer assay as decision points were placed into a computerized order entry menu. From December 2006 through November 2008, 261 pulmonary CTA examinations of 238 men and 14 women (mean age ± SD, 65 ± 12 years; range, 31-92 years) were performed. Eight patients underwent more than one pulmonary CTA examination. Charts were reviewed. The results of pulmonary CTA, the clinical decision rule, and d-dimer level (if obtained) were analyzed with the Student t test, chi-square test, or other comparisons using statistical software (MedCalc, version 11.0).

RESULTS

Of the pulmonary CTA examinations, 16.5% (43/261) were positive for pulmonary embolism (PE) compared with 3.1% (6/196) during the previous 2 years. The mean clinical decision rule score and mean d-dimer level were 5.5 ± 2.4 (SD) and 4956 ± 2892 ng/mL, respectively, for those with PE compared with 4.5 ± 2.1 and 2398 ± 2100 ng/mL for those without PE (both, p < 0.01). The negative predictive value of a clinical decision rule score of 4 or less and d-dimer level of less than 1000 ng/mL was 1.0. A clinical decision rule of greater than 4 and a higher d-dimer level were better predictors for PE, especially a d-dimer level of greater than 3000 ng/mL (odds ratio = 6.69; 95% CI = 2.72-16.43).

CONCLUSION

Guidelines combining a clinical decision rule with d-dimer level significantly improved the utilization of pulmonary CTA and positive yield for PE.

Serum asymmetric dimethylarginine, nitrate, vitamin B(12), and homocysteine levels in individuals with pulmonary embolism

We aimed to analyze the pre- and posttreatment serum asymmetric dimethylarginine (ADMA), nitrate (NO₃), vitamin B₁₂ and homocysteine levels in pulmonary embolism (PTE) patients and to determine the prognostic value of these variables in predicting chronic thromboembolic pulmonary hypertension (CTEPH). This study was conducted in 64 patients. The patients were classified into the two groups: patients with normal pulmonary artery pressure (PAP) (group I) and patients with high PAP with persistent lung perfusion defects or who died at the end of 3 months of therapy (group II). We found statistically significant differences between two groups with respect to the partial oxygen pressure, the oxygen saturation, and the PAP, but there was no difference between the two groups with respect to the pretreatment ADMA, NO₃, or homocysteine levels. The vitamin B₁₂ levels were higher in group II. The NO₃ levels increased and the ADMA and vitamin B₁₂ levels decreased with treatment in both groups. These results suggest that these parameters are not predictive of the development of CTEPH.

Treatment of Pulmonary Embolism Using Ultrasound-Accelerated Thrombolysis Directly Into Pulmonary Arteries

Traditional therapy for pulmonary embolism includes systemic anticoagulation, systemic thrombolysis, catheter-directed thrombolysis / suction catheter thrombectomy, and surgical thromboembolectomy. Currently, the standard treatment for submassive and massive pulmonary embolism involves the use of systemic anticoagulation. However, unlike systemic anticoagulation there is no standard treatment algorithm for the use of thrombolytics to aggressively treat pulmonary embolism and its sequelae. This case report discusses the successful use of thrombolytics using the EKOS EkoSonic Ultrasound-Accelerated Thrombolysis System in the treatment of bilateral submassive pulmonary emboli along with a saddle pulmonary embolus. The EKOS ultrasound-accelerated thrombolysis procedure resulted in rapid substantial clinical improvement, resolution of bilateral pulmonary emboli along with resolution of the saddle pulmonary embolus, restoration of pulmonary blood flow with resolution of pulmonary hypertension, and normalization of pulmonary embolism-related cardiac dysfunction. This novel application of ultrasound-accelerated thrombolytic infusion directly into the pulmonary arteries for pulmonary embolism provides a potential new treatment option and a valuable addition to the treatment algorithm for the management of both submassive and massive pulmonary embolism.

Diagnosis and management of life-threatening pulmonary embolism

Pulmonary embolus (PE) is estimated to cause 200 000 to 300 000 deaths annually. Many deaths occur in hemodynamically unstable patients and the estimated mortality for inpatients with hemodynamic instability is between 15% and 25%. The diagnosis of PE in the critically ill is often challenging because the presentation is nonspecific. Computed tomographic pulmonary angiography appears to be the most useful study for diagnosis of PE in the critically ill. For patients with renal insufficiency and contrast allergy, the ventilation perfusion scan provides an alternative. For patients too unstable to travel, echocardiography (especially transesophageal echocardiography) is another option. A positive result on lower extremity Doppler ultrasound can also aid in the decision to treat. The choice of treatment in PE depends on the estimated risk of poor outcome. The presence of hypotension is the most significant predictor of poor outcome and defines those with massive PE. Normotensive patients with evidence of right ventricular (RV) dysfunction, as assessed by echocardiography, comprise the sub-massive category and are at intermediate risk of poor outcomes. Clinically, those with sub-massive PE are difficult to distinguish from those with low-risk PE. Cardiac troponin, brain natriuretic peptide, and computed tomographic pulmonary angiography can raise the suspicion that a patient has sub-massive PE, but the echocardiogram remains the primary means of identifying RV dysfunction. The initial therapy for patients with PE is anticoagulation. Use of vasopressors, inotropes, pulmonary artery (PA) vasodilators and mechanical ventilation can stabilize critically ill patients. The recommended definitive treatment for patients with massive PE is thrombolysis (in addition to anticoagulation). In massive PE, thrombolytics reduce the risk of recurrent PE, cause rapid improvement in hemodynamics, and probably reduce mortality compared with anticoagulation alone. For patients with a contraindication to anticoagulation and thrombolytic therapy, surgical embolectomy and catheter-based therapies are options. Thrombolytic therapy in sub-massive PE results in improved pulmonary perfusion, reduced PA pressures, and a less complicated hospital course. No survival benefit has been documented, however. If one is considering the use of thrombolytic therapy in sub-massive PE, the limited documented benefit must be weighed against the increased risk of life-threatening hemorrhage. The role of surgical embolectomy and catheter-based therapies in this population is unclear. Evidence suggests that sub-massive PE is a heterogeneous group with respect to risk. It is possible that those at highest risk may benefit from thrombolysis, but existing studies do not identify subgroups within the sub-massive category. The role of inferior vena cava (IVC) filters, catheter-based interventions, and surgical embolectomy in life-threatening PE has yet to be completely defined.

The Impact of Age on the Delay in Diagnosis in Patients With Acute Pulmonary Embolism

It has been speculated that the atypical clinical presentation of acute pulmonary embolism (PE) in older patients leads to a late diagnosis and therefore contributes to a worse prognosis. Therefore, we prospectively evaluated the delay in diagnosis and its relation to the in-hospital mortality in 202 patients with acute PE. Patients >65 years presented more often with hypoxia ( P = .017) and with a history of syncope ( P = .046). Delay in diagnosis was not statistically different in both age groups. Older age was significantly associated with an increased risk for in-hospital mortality (OR 4.36, 95% CI 0.93-20.37, P = .043), whereas the delay in diagnosis was not associated with an increase of in-hospital mortality. We therefore conclude that the clinical presentation of acute PE in older patients cannot be considered as a risk factor for late diagnosis and is not responsible for their higher in-hospital death rate.

Improved outcome of surgical pulmonary embolectomy by aggressive intervention for critically ill patients

BACKGROUND

Acute massive pulmonary thromboembolism is a life-threatening disorder, and prompt treatment is necessary. We analyzed the outcome of pulmonary embolectomy for massive pulmonary embolism.

METHODS

Nineteen patients who underwent pulmonary embolectomy were retrospectively investigated. Average age of patients was 59 years, and 79% were female. Most patients had massive or submassive pulmonary thromboemboli dislodging into the main pulmonary trunk or bilateral main pulmonary arteries. Hemodynamics of most patients were unstable. Two patients required percutaneous cardiopulmonary support before embolectomy, and 4 required cardiopulmonary resuscitation. In 6 patients, thrombolysis was ineffective.

RESULTS

All patients underwent emergent pulmonary embolectomy. Operative mortality was 5.3%. No patients exhibited newly developed neurologic damage. Ten-year survival rate was 83.5% ± 8.7%.

CONCLUSIONS

Pulmonary embolectomy saves critically ill patients having acute massive pulmonary thromboembolism. We must evaluate pulmonary embolism patients with an algorithm that includes surgical embolectomy as one of several therapeutic options.

Use of fondaparinux in a pregnant woman with pulmonary embolism and heparin-induced thrombocytopenia

BACKGROUND

A serious complication of heparin treatment, heparin-induced thrombocytopenia (HIT) is rarely observed in pregnant women. Drug therapy during pregnancy should always be chosen to minimize fetal risk. The management of HIT in pregnancy represents a medical challenge. Unlike heparins, the anticoagulants used in patients with HIT do cross the placenta, with unknown fetal effects.

CASE REPORT

We present a case of a 24-year-old female presenting for care at 34 weeks of gestation with acute pulmonary embolism treated initially with unfractionated heparin (UFH) and low molecular weight heparin (LMWH), who developed HIT. She was then successfully treated with fondaparinux.

CONCLUSIONS

To the best of our knowledge, this is one of the first case reports describing a successful use of fondaparinux in the treatment of HIT in a third-trimester pregnant woman, providing a novel approach for this subset of patients.

Electrocardiogram score predicts severity of pulmonary embolism in hemodynamically stable patients

BACKGROUND

Risk stratification of patients with pulmonary embolism (PE) is essential to guide therapy. The presence of right ventricle dysfunction (RVD) and the anatomic extent of PE have been suggested to predict clinical course. The aim of this study was to assess the ability of an electrocardiogram (ECG) scoring system to predict RVD or the clot load score in normotensive patients with PE.

METHODS

Consecutive patients presenting to the emergency room with PE and hemodynamic stability were prospectively included. ECG, echocardiography and computed tomography pulmonary angiography (CTPA) were performed on all patients.

RESULTS

A total of 103 patients were studied. ECG score correlated significantly with the clot load score (r = 0.41, 95% confidence interval [CI]: 0.22-0.57, P < 0.001), systolic pulmonary artery pressure (r= 0.31, 95% CI: 0.09-0.49, P = 0.006), pulmonary artery diameter (r = 0.28, 95% CI: 0.07-0.47, P = 0.011) and right ventricle to left ventricle ratio, both measured with echocardiography (r = 0.42, 95% CI: 0.22-0.57, P < 0.001) and with CTPA (r= 0.36, 95% CI: 0.13-0.56, P = 0.004). Area under the receiver operating characteristic curve for detecting RVD was 0.82 (95% CI: 0.72-0.89). Interobserver agreement regarding ECG score was substantial (κ = 0.80).

CONCLUSIONS

ECG score correlates with the severity of PE in hemodynamically stable patients. It is potentially useful for risk-stratification strategies in this setting.

Reduction in membrane component of diffusing capacity is associated with the extent of acute pulmonary embolism

Acute pulmonary embolism (PE) often decreases pulmonary diffusing capacity for carbon monoxide (DL,CO), but data on the mechanisms involved are inconsistent. We wanted to investigate whether reduction in diffusing capacity of alveolo-capillary membrane (DM) and pulmonary capillary blood volume (Vc) is associated with the extent of PE or the presence and severity of right ventricular dysfunction (RVD) induced by PE and how the possible changes are corrected after 7-month follow-up. Forty-seven patients with acute non-massive PE in spiral computed tomography (CT) were included. The extent of PE was assessed by scoring mass of embolism. DL,CO, Vc, DM and alveolar volume (VA) were measured by using a single breath method with carbon monoxide and oxygen both at the acute phase and 7 months later. RVD was evaluated with transthoracic echocardiography and electrocardiogram. Fifteen healthy subjects were included as controls. DL,CO, DL, CO/VA, DM, vital capacity (VC) and VA were significantly lower in the patients with acute PE than in healthy controls (P < 0.001). DM/Vc relation was significantly lower in patients with RVD than in healthy controls (P = 0.004). DM correlated inversely with central mass of embolism (r = -0.312; P = 0.047) whereas Vc did not. DM, DL,CO, VC and VA improved significantly within 7 months. In all patients (P = 0.001, P = 0.001) and persistent RVD (P = 0.020, P = 0.012), DM and DL,CO remained significantly lower than in healthy controls in the follow-up. DM was inversely related to central mass of embolism. Reduction in DM mainly explains the sustained decrease in DL,CO in PE after 7 months despite modern treatment of PE.

Challenges, controversies, and hot topics in pulmonary embolism imaging

OBJECTIVE

The purpose of this article is to discuss the diagnostic role of pulmonary CT angiography (CTA) in the workup of pulmonary embolism (PE), including specific populations, and issues such as pulmonary CTA combined with indirect CT venography; radiation dose considerations; the management of isolated subsegmental PE; and new technologic developments, such as dual-source/dual-energy pulmonary CTA.

CONCLUSION

The role of pulmonary CTA will continue to grow with the emergence of MDCT and dual-energy CT and their improved capabilities. However, the need for any given CT examination should always be justified on the basis of the individual patient's benefits and risks.

Multidetector computed tomography for acute pulmonary embolism: diagnosis and risk stratification in a single test

AIMS

In patients with acute pulmonary embolism (PE), right ventricular dysfunction at echocardiography is associated with increased in-hospital mortality. The aims of this study in patients with acute PE were to identify a sensitive and simple criterion for right ventricular dysfunction at multidetector computed tomography (MDCT) using echocardiography as the reference standard and to evaluate the predictive value of the identified MDCT criterion for in-hospital death or clinical deterioration.

METHODS AND RESULTS

Right ventricular dysfunction at MDCT was defined as the right-to-left ventricular dimensional ratio and was centrally assessed by a panel unaware of clinical and echocardiographic data. A right-to-left ventricular dimensional ratio ≥0.9 at MDCT had a 92% sensitivity for right ventricular dysfunction [95% confidence interval (CI) 88-96]. Overall, 457 patients were included in the outcome study: 303 had right ventricular dysfunction at MDCT. In-hospital death or clinical deterioration occurred in 44 patients with and in 8 patients without right ventricular dysfunction at MDCT (14.5 vs. 5.2%; P< 0.004). The negative predictive value of right ventricular dysfunction for death due to PE was 100% (95% CI 98-100). Right ventricular dysfunction at MDCT was an independent predictor for in-hospital death or clinical deterioration in the overall population [hazard ratio (HR) 3.5, 95% CI 1.6-7.7; P= 0.002] and in haemodynamically stable patients (HR 3.8, 95% CI 1.3-10.9; P= 0.007).

CONCLUSION

In patients with acute PE, MDCT might be used as a single procedure for diagnosis and risk stratification. Patients without right ventricular dysfunction at MDCT have a low risk of in-hospital adverse outcome.

Soluble CD40 ligand levels in acute pulmonary embolism: a prospective, randomized, controlled study

CD40 ligand is a thromboinflammatory molecule that predicts cardiovascular events. Platelets constitute the major source of soluble CD40 ligands (sCD40L), which has been shown to influence platelet activation. The main aim of this study was to evaluate sCD40L levels in patients with acute pulmonary embolism (PE). Sixty-five PE patients (32 males, mean age 58 ± 12 years) and 29 healthy controls (15 males, mean age 56 ± 14 years) were enrolled in the study. sCD40L levels were evaluated at the enrollment by ELISA method. Multislice detected pulmonary computed tomography was performed on all patients with a suspected diagnosis of PE. In addition, echocardiography was performed to evaluate right ventricular (RV) dysfunction. There was no statistically significant difference between the two groups regarding demographic features. sCD40L levels were significantly higher in acute PE group compared to healthy controls (5.3 ng/ml and 1.4 ng/ml, respectively; p < 0.001). sCD40L levels of patients with and without RV dysfunction were similar. Correlation analysis between echocardiographic findings and sCD40L levels did not show significant difference. The present study demonstrated a role of sCD40L in pathogenesis of PE for the first time. Further studies are needed to clarify a predictive and prognostic value of sCD40L levels in acute PE patients.

Imaging of non-cardiac, non-traumatic causes of acute chest pain

Non-traumatic chest pain is a common symptom in patients who present in the emergency department. From a clinical point of view, it is important to differentiate cardiac chest pain from non-cardiac chest pain (NCCP). Among the plethora of potential causes of NCCP, life-threatening diseases, such as aortic dissection, pulmonary embolism, tension pneumothorax, and esophageal rupture, must be differentiated from non-life threatening causes. The majority of NCCP, however, is reported to be benign in nature. The presentation of pain plays an important role in narrowing the differential diagnosis and initiating further diagnostic management and treatment. As the benign causes tend to recur, and may lead to patient anxiety and great costs, a meticulous evaluation of the patient is necessary to diagnose the underlying disorder or disease.

How do I manage a patient with suspected acute pulmonary embolism?

Acute PE is a cardiovascular emergency and early risk stratification is important in the management of these patients. Pre-test clinical prediction models together with D-dimer assays help select those who require imaging. Each hospital should develop a strategy for investigating patients with suspected PE depending on local expertise, resources and the patient population.

Prognostic value of the Geneva prediction rule in patients in whom pulmonary embolism is ruled out

OBJECTIVES

The prognosis of patients in whom pulmonary embolism (PE) is suspected but ruled out is poorly understood. We evaluated whether the initial assessment of clinical probability of PE could help to predict the prognosis for these patients.

DESIGN

Retrospective analysis of data obtained during a prospective multicentre management study.

SETTING

Six general and teaching hospitals in Belgium, France and Switzerland.

SUBJECTS

In 1334 patients in whom PE was ruled out, 3-month mortality data were available (hospital readmission status was unknown for three patients) and clinical probability was evaluated with the revised Geneva score (RGS).

MAIN OUTCOME MEASURES

Three-month mortality and readmission rates.

RESULTS

Three-month mortality and readmissions rates were 3% and 19%, respectively and differed significantly depending on the RGS-determined PE probability group (P<0.001). When compared with patients presenting with a low probability, the risk of death after 3 months was higher in cases of intermediate or high RGS-based probability {odds ratio: 8.7 [95% confidence interval (CI): 2.7-28.5] and 22.6 (95%CI: 2.1-241.2), respectively}. The readmission risk increased with PE probability group (P<0.001). The main causes of death were cancer, respiratory failure and cardiovascular failure. In total, 86% of patients with low RGS-based probability were alive and had not been readmitted to hospital, whereas other patients had a twofold increased risk of death or readmission during the 3-month follow-up. The simplified Geneva score, calculated a posteriori, gave similar results.

CONCLUSIONS

Initial assessment of clinical probability may help to stratify prognosis of patients in whom PE has been ruled out. Patients with a low probability of PE have a good prognosis. Whether patients with higher probability might benefit from more vigilant care should be evaluated.

Computed tomography and magnetic resonance imaging of pulmonary hypertension: Pulmonary vessels and right ventricle

Pulmonary hypertension (PH) is very heterogeneous and the classification identifies five major groups including many associated disease processes. The treatment of PH depends on the underlying cause and accurate classification is paramount. A comprehensive assessment to identify the cause and severity of PH is therefore needed. Furthermore, follow-up assessments are required to monitor changes in disease status and response to therapy. Traditionally, the diagnostic imaging work-up of PH comprised mainly echocardiography, invasive right heart catheterization, and ventilation/perfusion scintigraphy. Due to technical advances, multidetector row computed tomography (CT) and magnetic resonance imaging (MRI) have become important and complementary investigations in the evaluation of patients with suspected PH. Both modalities are reviewed and recommendations for clinical use are given.

The prognostic value of markers of right ventricular dysfunction in pulmonary embolism: a meta-analysis

Introduction

In pulmonary embolism (PE) without hemodynamic compromise, the prognostic value of right ventricular (RV) dysfunction as measured by echocardiography, computed tomography (CT) or biological (natriuretic peptides) markers has only been assessed in small studies.

Methods

Databases were searched using the combined medical subject headings for right ventricular dysfunction or right ventricular dilatation with the exploded term acute pulmonary embolism. This retrieved 8 echocardiographic marker based studies (n = 1249), three CT marker based studies (n = 503) and 7 natriuretic peptide based studies (n = 582). A meta-analysis of these data was performed with the primary endpoint of mortality within three months after pulmonary embolism, and a secondary endpoint of overall mortality and morbidity by pulmonary embolism.

Results

Patients with PE without hemodynamic compromise on admission and the presence of RV dysfunction determined by echocardiography and biological markers were associated with increased short-term mortality (odds ratio (OR) _ECHO = 2.36; 95% confidence interval (CI): 1.3-43; OR _BNP = 7.7; 95% CI: 2.9-20) while CT was not (OR_CT = 1.54-95% CI: 0.7-3.4). However, corresponding pooled negative and positive likelihood ratios independent of death rates were unsatisfactory for clinical usefulness in risk stratification.

Conclusions

The presence of echocardiographic RV dysfunction or elevated natriuretic peptides is associated with short-term mortality in patients with pulmonary embolism without hemodynamic compromise. In contrast, the prognostic value of RV dilation on CT has yet to be validated in this population. As indicated both by positive and negative likelihood ratios the current prognostic value in clinical practice remains very limited.

Management of massive and submassive pulmonary embolism, iliofemoral deep vein thrombosis, and chronic thromboembolic pulmonary hypertension: a scientific statement from the American Heart Association

Venous thromboembolism (VTE) is responsible for the hospitalization of >250 000 Americans annually and represents a significant risk for morbidity and mortality. Despite the publication of evidence-based clinical practice guidelines to aid in the management of VTE in its acute and chronic forms, the clinician is frequently confronted with manifestations of VTE for which data are sparse and optimal management is unclear. In particular, the optimal use of advanced therapies for acute VTE, including thrombolysis and catheter-based therapies, remains uncertain. This report addresses the management of massive and submassive pulmonary embolism (PE), iliofemoral deep vein thrombosis (IFDVT),and chronic thromboembolic pulmonary hypertension (CTEPH). The goal is to provide practical advice to enable the busy clinician to optimize the management of patients with these severe manifestations of VTE. Although this document makes recommendations for management, optimal medical decisions must incorporate other factors, including patient wishes, quality of life, and life expectancy based on age and comorbidities. The appropriateness of these recommendations for a specific patient may vary depending on these factors and will be best judged by the bedside clinician.

[Initial antithrombotic therapy for pulmonary embolism]

The initial therapy for patients with pulmonary embolism who are haemodynamically stable relies on antithrombotic treatment. The aim of anticoagulant treatment is to prevent any thrombus extension or recurrence, with revascularization dependent on the fibrinolytic system. Current treatment is biphasic, with parenteral heparin or derivatives (low molecular weight heparins and fondaparinux) followed by oral vitamin K antagonists. Although these treatments are efficient, they suffer from some limitations including parenteral administration and the need for surveillance and monitoring. Use of low molecular weight heparins or fondaparinux is recommended in French guidelines, but unfractionated heparin still has an important role in some specific situations such as severe renal insufficiency, around the time of surgery and where there is a high risk of bleeding. The next generation of anticoagulants will soon be licensed for treatment in pulmonary embolism and may well replace heparin and/or vitamin K antagonists for the majority of patients, although "older" treatments will always be requested in some specific situations.

Clinical assessment of chest pain and guidelines for imaging

For many emergency facilities, risk assessment of patients with diffuse chest pain still poses a major challenge. In their currently valid recommendations, the international cardiological societies have defined a standardized assessment of the prognostically relevant cardiac risk criteria. Here the classic sequence of basic cardiac diagnostics including case history (cardiac risk factors), physical examination (haemodynamic and respiratory vital parameters), ECG (ST segment analysis) and laboratory risk markers (troponin levels) is paramount. The focus is, on the one hand, on timely indication for percutaneous catheterization, especially in patients at high cardiac risk with or without ST-segment elevation in the ECG, and, on the other hand, on the possibility of safely discharging patients with intermediate or low cardiac risk after non-invasive exclusion of a coronary syndrome. For patients in the intermediate or low risk group, physical or pharmacological stress testing in combination with scintigraphy, echocardiography or magnetic resonance imaging is recommended in addition to basic diagnostics. Moreover, the importance of non-invasive coronary imaging, primarily cardiac CT angiography (CCTA), is increasing. Current data show that in intermediate or low risk patients this method is suitable to reliably rule out coronary heart disease. In addition, attention is paid to the major differential diagnoses of acute coronary syndrome, particularly pulmonary embolism and aortic dissection. Here the diagnostic method of choice is thoracic CT, possibly also in combination with CCTA aiming at a triple rule-out.

Clinical prediction of pulmonary embolism in respiratory emergencies

INTRODUCTION

The initial management of suspected pulmonary embolism (PE) is commonly done in respiratory departments, but is based on clinical prediction rules developed in other settings.

OBJECTIVE

To determine the accuracy of established prediction rules for PE in patients with respiratory emergencies.

DESIGN

A prospective study

MATERIALS AND METHODS

Patients presenting to respiratory emergency department with acute symptoms and signs suggestive of PE (n=183) and subsequently admitted to hospital were prospectively enrolled. Wells' rule, original and revised Geneva scores, their components separately, and other common clinical parameters were recorded during admission. PE was diagnosed by perfusion lung scanning, computed tomographic pulmonary angiography, lower limb venous ultrasonography, magnetic resonance pulmonary angiography, and/or pulmonary angiography.

RESULTS

PE was confirmed in 52 and ruled out in 131 patients. Tachycardia, atelectasis, elevated hemidiaphragm, clinical signs of deep-venous thrombosis, physician perception that PE is the likeliest diagnosis, previous thromboembolism, chest pain, and absence of chronic obstructive pulmonary disease or cough were associated with the presence of PE. These significant parameters could be combined for accurate pre-test PE prediction, with a newly devised combinatorial tool exhibiting the highest area under curve [0.92 (95% CI: 0.87-0.97)], followed by Wells' rule [0.86 (95% CI 0.79-0.92)], the revised Geneva score [0.83 (95% CI 0.77-0.90)], and the original Geneva score [0.75 (95% CI 0.68-0.83)].

CONCLUSION

Wells' rule and the revised Geneva score are more useful in diagnosing PE in respiratory emergencies. A newly devised prediction tool can be of even greater accuracy in this patient population.

Use of imaging for investigation of suspected pulmonary embolism during pregnancy and the postpartum period

Pulmonary embolism (PE) is recognized as a leading cause of maternal mortality in the developed world; however, it is a very difficult diagnosis to make on clinical grounds, and in most cases imaging is required. Pregnancy is a recognized risk factor for venous thromboembolism, and symptoms of normal pregnancy including shortness of breath, tachycardia and leg swelling are included in clinical tools for risk stratification for PE in the non-pregnant population. This results in a very low threshold for imaging, despite concerns regarding the risk of exposure to ionizing radiation both for the fetus and the maternal breast. We reviewed the results of all ventilation/perfusion scans and computed tomography pulmonary angiograms performed in pregnant women at a single institution to identify how many of these tests were positive for PE, and which clinical features may identify a low-risk group. A total of 386 scans were performed to investigate 375 episodes of suspected PE, representing 1.3-1.5% of pregnant women. Fifteen patients were diagnosed with PE, giving an incidence of one in 2000 maternities. The only statistically significant factors associated with PE were smoking or the presence of multiple risk factors. Clinical features of tachycardia and leg swelling did not provide significant diagnostic value; however, the absence of pleuritic chest pain had a negative predictive value of 97.8%. Arterial blood gas and D-dimer were statistically different between those with and without PE but not to a clinically useful degree. Currently available clinical and laboratory tools are not adequate to exclude a diagnosis of PE in a pregnant patient, thus imaging is justified to exclude PE. Further longitudinal studies to identify a low-risk group who do not require imaging is vital.

Dynamic composition of semantic pathways for medical computational problem solving by means of semantic rules

This paper presents a semantic rule-based system for the composition of successful algorithmic pathways capable of solving medical computational problems (MCPs). A subset of medical algorithms referring to MCP solving concerns well-known medical problems and their computational algorithmic solutions. These solutions result from computations within mathematical models aiming to enhance healthcare quality via support for diagnosis and treatment automation, especially useful for educational purposes. Currently, there is a plethora of computational algorithms on the web, which pertain to MCPs and provide all computational facilities required to solve a medical problem. An inherent requirement for the successful construction of algorithmic pathways for managing real medical cases is the composition of a sequence of computational algorithms. The aim of this paper is to approach the composition of such pathways via the design of appropriate finite-state machines (FSMs), the use of ontologies, and SWRL semantic rules. The goal of semantic rules is to automatically associate different algorithms that are represented as different states of the FSM in order to result in a successful pathway. The rule-based approach is herein implemented on top of Knowledge-Based System for Intelligent Computational Search in Medicine (KnowBaSICS-M), an ontology-based system for MCP semantic management. Preliminary results have shown that the proposed system adequately produces algorithmic pathways in agreement with current international medical guidelines.

Interventional therapies for venous thromboembolism: vena caval interruption, surgical embolectomy, and catheter-directed interventions

Therapeutic strategies other than anticoagulation sometimes require consideration in the setting of acute venous thromboembolism. Vena caval filter placement is increasingly common, in part because of the availability of nonpermanent filter devices. Filter placement, surgical embolectomy, and catheter embolectomy have not been subjected to the same prospective, randomized clinical trial scrutiny as anticoagulation but seem appropriate in certain clinical settings. The indications, contraindications, and available data supporting these therapeutic methods are discussed.

[Pulmonary thromboembolism]

Pulmonary thromboembolism is a frequent disease in emergency departments and often poses a diagnostic challenge that requires appropriate strategies. Clinical information, laboratory tests such as a D-dimer and imaging techniques such as computed tomography (CT) angiography, ventilation-perfusion scintigraphy or echocardiography help to establish clinical probability and the severity of the disease. With all this information, risk scores can be constructed, such as the Pulmonary Embolism Severity Index (PESI) score, which has high sensitivity in predicting mortality. Treatment should be started immediately with heparin, usually low molecular weight heparin. If the patient is at high risk, thrombolytic therapy is indicated, although possible contraindications should be thoroughly assessed. Supportive treatment may be considered in a few patients.

Six-month echocardiographic study in patients with submassive pulmonary embolism and right ventricle dysfunction: comparison of thrombolysis with heparin

INTRODUCTION

The aim of this study was to assess the effect of thrombolysis versus heparin treatment on echocardiographic parameters and clinical outcome, during hospitalization and within the first 180 days after admission, in patients with first episode of submassive pulmonary embolism (SPE) and right ventricle dysfunction (RVD).

METHODS

Consecutive patients (age, 18-75 years) with a first episode of SPE, symptoms onset since no more than 6 hours, normal blood pressure (>100 mm Hg), echocardiographic evidence of RVD and positive lung spiral computed tomography were double-blind randomized: 1 group received 100 mg of alteplase (10-mg bolus, followed by a 90-mg intravenous infusion over a period of 2 hours), while the other group received matching placebo. In addition to alteplase or placebo, both groups received an unfractionated heparin treatment. Echocardiogram was performed at admission, at 24, 48 and 72 hours, at discharge and at 3 and at 6 months after randomization.

RESULTS

Seventy-two patients were included into the study; 37 were assigned to thrombolysis and 35 to placebo. Both groups were well matched with regard to features and clinical presentation. Thrombolysis group showed a significant early improvement of RV function compared with heparin group, and this improvement was observed also during the follow-up (180 days). The same group also showed significant reduction in clinical events during the hospitalization and follow-up.

CONCLUSIONS

Our data suggest that, in hemodynamically stable patients with SPE, thrombolysis shows an earliest reduction of RVD and a more favorable trend in clinical outcome, so, it could merit consideration in SPE.

Are biomarkers additive to pulmonary embolism severity index for severity assessment in normotensive patients with acute pulmonary embolism?

BACKGROUND

Biomarkers and clinical prediction rules have been proposed for severity assessment in acute pulmonary embolism (PE).

AIM

The aim of this study was to compare biomarkers with the PE Severity Index (PESI), a validated scoring system for predicting 30-day mortality and to determine if addition of biomarkers to PESI would improve its predictive accuracy.

STUDY DESIGN AND METHODS

We conducted a retrospective analysis of normotensive patients admitted with PE confirmed by CT pulmonary angiogram, to three teaching hospitals between January 2005 and July 2007. All patients had admission levels of D-dimer and Troponin I and calculation of PESI score on admission. The outcome of interest was 30-day mortality.

RESULTS

There were 411 patients included in the study. Patients who died had higher levels of D-dimer (median 2947 ng/ml vs. 1464 ng/ml; P=0.02), Troponin (57.1% positive vs. 13.8%; P<0.0001) and higher PESI scores [median 109 vs. 83; P<0.0001], compared to survivors. PESI had superior accuracy for predicting 30-day mortality than a combination of Troponin and D-dimer (AUC 0.80 vs. 0.75). Addition of Troponin to PESI further improved the predictive value of the score (AUC 0.85 for vs. AUC 0.80 for PESI alone).

CONCLUSION

Biomarkers and clinical prediction rules predict outcome in acute PE. Addition of troponin to the PESI scoring system improves the predictive value for 30-day mortality and may be useful for guiding initial management of patients presenting with PE.

[The patient with pulmonary embolism or vascular emergency requiring intensive care]

Acute pulmonary embolism requires ICU management only for patients with hemodynamic instability who need artificial ventilation, or for hemodynamically stable patients with significant right ventricular dysfunction. For both patient groups, echocardiography is the most relevant diagnostic method. The main therapeutic consideration is on systemic thrombolysis. It is indicated in almost all patients with hemodynamic instability but only in selected cases of right ventricular dysfunction. All other patients receive standard anticoagulation only. A second vascular emergency scenario is type 2 heparin-induced thrombocytopeniae (HIT II) which may cause venous as well as arterial complications. Alternative anticoagulation has to be established from the first moment of clinical suspicion. It has to be continued in a therapeutic dosage if HIT II is confirmed, and has to be stopped if the diagnosis is refuted. The latter case is by far more frequent. Regarding arterial occlusions (acute limb ischemia, acral gangrene, iatrogenic vascular trauma) hints are given for the management in the setting of intensive care.