Diagnostic Tests For Pulmonary Embolism Research Articles

Hot Off the Press: SGEM #276-FOCUS on PE in Patients With Abnormal Vital Signs.

Pulmonary embolism (PE) is commonly suspected in patients presenting to the emergency department, however the gold-standard diagnostic test of CTA of the pulmonary arteries cannot always be performed rapidly. Focused cardiac ultrasound (FOCUS) has been studied previously as a diagnostic test for PE, with mixed results. We review a study by Daley et al in which the authors evaluated the diagnostic utility of FOCUS for PE in patients with unstable vital signs. We provide critical analysis of the article, as well as summarize the social media discussion and feedback of a podcast in which the authors discuss their work.

Over-Testing for Suspected Pulmonary Embolism in American Emergency Departments: The Continuing Epidemic.

No recent data have investigated rates of diagnostic testing for pulmonary embolism (PE) in US emergency departments (EDs), and no data have examined computed tomographic pulmonary angiography (CTPA) rates in subgroups at high risk for adverse imaging outcomes, including young women and children. We hypothesized that over-testing for PE remains a problem. We used electronic health record and billing data for 16 EDs in Indiana and 11 hospitals in the Dallas-Fort Worth area from 2016 to 2019 to locate ED patients who had any of the following: D-dimer, CTPA, scintillation ventilation perfusion lung scanning or formal pulmonary angiography. The primary outcomes were ED encounter volume-adjusted CTPA rate, PE yield rate with subgroup reporting for children (<18 years) and women under 45 years. We also examined the most frequent diagnoses. From a total visit volume of 1 828 010 patient encounters, 97 125 (5.3% of the total volume) had a diagnostic test for PE, including 25 870 patients who had CTPA order without D-dimer (59% of all tests for PE). The yield rate for PE from CTPA scans was 1.3% (1.1%-1.5%) in Indiana and 4.8% (4.2%-5.1%) in Dallas-Fort Worth (pooled rate 3.1%). Linear regression showed that increased D-dimer ordering correlated with increased PE yield rate (Pearson's R2=0.43; P<0.001). From the pooled sample, 59% of CTPAs done were in women, with 21% of all CTPAs performed on women under 45 years of age, and 1.4% (1.3%-1.5%) on children. The most frequent diagnoses were symptom-based descriptions of chest pain (34%) and shortness of breath (6.5%) and the condition-based diagnosis of pneumonia (4.1%). Over-testing for PE in American EDs remains a major public health problem. Centers with higher D-dimer ordering had higher yield of PE on CTPA. These data suggest the potential for implementation of D-dimer based protocols to reduce low-yield CTPA ordering.

Differential diagnostic dilemma between pulmonary embolism and acute coronary syndrome

Acute pulmonary embolism (PE) is a frequent life-threatening condition in emergency departments. Careful diagnosis is important, and different diagnostic tests such as electrocardiogram (ECG), biochemical markers, echocardiogram, and computed tomography are required. Although ECG is a cheap and rapid diagnostic test for pulmonary embolism, it has some limitations in the differential diagnosis of acute coronary syndrome and acute PE. Herein, we report ECG results of a patient diagnosed with acute PE mimicking acute coronary syndrome.

Transthoracic Sonography for the Detection of Pulmonary Embolism – a Meta-Analysis

Radiation protection is a major issue since the implementation of MSCT technology and its widespread indication for the detection of various diseases. In a European-wide trial (SECT) meta-analyses of imaging alternatives to CT have been initiated. This paper focuses on the diagnostic performance of transthoracic ultrasound (TUS) for the diagnosis of pulmonary embolism (PE) (5 studies, 652 patients). Medical literature (from 1990 to 2006) in PubMed and EMBASE databases was searched for articles on studies that used TUS as diagnostic tests for PE. Studies were included if they reported the positive and negative rates of PE diagnoses from TUS compared with the rates of PE in CT, MRI or a combination of diagnostic tests. Two readers assessed the quality of the studies. Pooled sensitivity and specificity of TUS for PE were 80 % (95 % CI: 75 %, 83 %) and 93 % (95 % CI: 89 %, 96 %), respectively. In the time of MSCT, TUS is an imaging modality that is no longer part of recent diagnostic algorithms for the diagnosis of PE. Considering the increasing number of requested CT examinations and therefore increasing collective radiation dose, this meta-analysis shows that TUS is a diagnostic alternative for special clinical settings in the work-up of suspected PE that seems to have fallen into oblivion.

Echocardiographic Predictors of Pulmonary Embolism in Patients Referred for Helical CT

Transthoracic echocardiography (TTE) is ordered frequently in patients with suspected pulmonary embolism (PE). Multiple indices have been suggested to play a useful diagnostic role. We sought to determine the relative predictive accuracy of suggested quantitative indices among patients referred for CT scanning for exclusion of PE. We retrospectively identified 67 consecutive patients who underwent CT for the exclusion of PE, and had a TTE within 48 hours of CT. Echo indices suggested to play a role in the diagnosis of PE were measured RV/LV area ratio, RV/LV end diastolic dimension ratio, the "McConnell" sign, interventricular septal shift ("D-sign"), Pulmonary artery diameter, tricuspid regurgitation velocity, and "60/60 sign" (TR velocity < 3.9 m/sec plus pulmonary artery acceleration time < 60 msec). CT confirmed PE in 41 (61%). Mean age was 58 (18-92). Forty-five were female. Subjects with PE were younger, and more likely to be tachycardic and require ICU admission. Of the echocardiographic indices, RV/LV EDD ratio > 0.7 was the most accurate predictor (sensitivity 66%, specificity 77%). The McConnell sign was the most specific (96%), however, with poor sensitivity (16%). Mean TR velocities did not differ between those with and without PE (270 +/- 74 vs. 294 +/- 83, P = 0.25). RV/LV EDD ratio > 0.7 has good accuracy for the diagnosis of acute PE. RV/LV area ratio > 0.7 and McConnell sign are specific but not sensitive indicators of acute pulmonary embolism. The presence of these findings should prompt further diagnostic testing for PE.

D-dimer and BNP levels in acute aortic dissection

Early diagnosis and treatment are pivotal for patients with acute aortic dissection (AAD). D-dimer is a rule-out diagnostic test for pulmonary embolism but there is evidence that it may also be applicable to AAD. We evaluated plasma D-dimer, white cell blood count (WBC), C-reactive protein (CRP) and N-terminal pro-B-type natriuretic peptide (BNP) in 18 consecutive patients with established AAD, 21 consecutive patients with dilated ascending aortas scheduled for elective surgery and 8 normal subjects. Patients with AAD had significantly higher elevated D-dimer, compared to chronic aneurysms and normal controls ( p < 0.0001). D-dimer level higher than 700 ng/ml had a sensitivity of 94% and specificity of 59% for diagnosis of AAD. The WBC count was also significantly increased compared to the other groups ( p < 0.01). CRP and BNP values were significantly higher compared to normal controls but these parameters did not distinguish between AAD and chronic aneurysms. D-dimer can be used as a ‘rule-out’ test in patients with suspected AAD and seems useful in the discrimination between AAD and chronic uncomplicated aneurysms, unlike CRP and BNP plasma levels.

Diagnosis of pulmonary embolism: in transition

To discuss reports published in 2005 on the diagnosis of clinically suspected nonmassive pulmonary embolism. Progress has been made in assessing the clinical probability of pulmonary embolism, in addressing diagnosis in the elderly, in evaluating the diagnostic performance of single-detector and multidetector row helical computed tomography, and in the role of D-dimer measurement and lower limb venous compression ultrasonography in the diagnostic work-up of pulmonary embolism. Diagnosing venous thromboembolism depends mainly on noninvasive diagnostic tools that are used sequentially. In most patients, a noninvasive work-up is feasible and the diagnostic algorithms are becoming simpler. This review focuses on developments in clinical probability assessment, pulmonary embolism in the elderly, potential new uses of D-dimer measurement, advent of multidetector row helical computed tomography, and utility of ultrasonography in detecting deep vein thrombosis in patients with suspected pulmonary embolism. With the development of potentially more sensitive diagnostic tests for pulmonary embolism, physicians are now facing the risk of overdiagnosis and hence overtreatment. The issue will no longer be just to detect clots but to identify patients who must be treated using anticoagulants, a complicated question.

An Evaluation of d-Dimer in the Diagnosis of Pulmonary Embolism

It may be safe to omit additional diagnostic testing in selected patients with suspected pulmonary embolism (PE) who have a negative D-dimer test, but this approach has never been evaluated in a randomized, controlled trial. To determine if additional diagnostic testing can be safely withheld in patients with suspected PE who have negative erythrocyte agglutination D-dimer test results. Randomized comparisons in 2 subgroups of a prospective multicenter study. 7 university hospitals. 1126 outpatients or inpatients with suspected PE; of these, 456 patients with negative erythrocyte agglutination D-dimer test results were randomly assigned to the intervention groups. Patients were classified into 2 clinical probability groups: those with a low clinical probability of PE (low-probability group) and those with a moderate or high clinical probability of PE, a nondiagnostic ventilation-perfusion lung scan, and no evidence of proximal deep venous thrombosis on bilateral ultrasonography (moderate- or high-probability group). The experimental intervention for both probability groups was no further diagnostic testing for PE. The control intervention for the low-probability group was a ventilation-perfusion lung scan followed by ultrasonography of the proximal deep veins of the legs on the same day. If the lung scan was nondiagnostic, ultrasonography of the legs was repeated 7 and 14 days later. The control intervention for the moderate- or high-probability group was ultrasonography of the proximal deep veins of the legs after 7 and 14 days. In the control and experimental groups, anticoagulation was withheld or withdrawn if PE was not diagnosed. Symptomatic venous thromboembolism (VTE) during 6 months of follow-up. Prevalence of VTE was 15.2% in the 1126 enrolled patients. In the low-probability group, VTE occurred during follow-up in 0 of 182 patients who had no additional diagnostic testing and in 1 of 185 patients who had additional testing (difference, -0.5 percentage point [95% CI, -3.0 to 1.6 percentage points]). In the moderate- or high-probability group, VTE occurred during follow-up in 1 of 41 patients who had no additional diagnostic testing and in 0 of 41 patients who had additional testing (difference, 2.4 percentage points [CI, -6.4 to 12.6 percentage points]). The authors could not enroll 2000 patients as originally planned; 3 randomly assigned patients did not receive the allocated intervention, and 7 received inadequate follow-up. Personnel who performed follow-up evaluations were not blinded to the results of diagnostic testing at enrollment or to allocation group assignments. In patients with a low probability of PE who have negative D-dimer results, additional diagnostic testing can be withheld without increasing the frequency of VTE during follow-up. Low clinical probability and negative D-dimer results occur in 50% of outpatients and in 20% of inpatients with suspected PE.

Respiratory Dead Space Measurement in the Investigation of Pulmonary Embolism in Outpatients With Pleuritic Chest Pain

Pleuritic chest pain is a common presenting condition in the emergency department. A noninvasive bedside rule out test for pulmonary embolism would aid investigating this patient group. Our study aimed to compare the clinical utility of three methods for calculating respiratory dead space in the diagnosis of pulmonary embolism in outpatients with pleuritic chest pain. Prospective diagnostic study. Large city-center emergency department. Between February 2002 and June 2003, 425 patients presenting to the emergency department with pleuritic chest pain were prospectively recruited. Data collection for respiratory dead space was performed in the emergency department by two researchers. The respiratory dead space fraction was calculated independently using three different methods. All patients underwent an independent reference standard diagnostic algorithm to establish the presence or absence of pulmonary embolism. Those with a low modified Wells clinical probability and a normal quantitative d-dimer finding were discharged home. All others followed a reference standard protocol using Prospective Investigation of Pulmonary Embolism Diagnosis-interpreted ventilation/perfusion scanning, CT pulmonary angiography, and digital subtraction pulmonary angiography. All patients were followed up clinically for 3 months. For the Bohr calculation, the area under the receiver operating characteristic curve was 0.62 (95% confidence interval [CI], 0.51 to 0.73), the Enghoff calculation was 0.66 (95% CI, 0.55 to 0.77), and the capillary sample Enghoff was 0.62 (95% CI, 0.49 to 0.65). The optimum Bohr cutoff value gave 100.0% sensitivity (95% CI, 84.5 to 100%) but a low specificity of 22.7% (95% CI, 18.8 to 27.2%). The optimum cutoff points for Enghoff and capillary Enghoff calculations gave sensitivities of 95.3% (95% CI, 77.3 to 99.2%) and 94.4% (95% CI, 74.2 to 99.0%), respectively, with poor specificity. Respiratory dead space analysis does not perform well as a stand-alone diagnostic test for pulmonary embolism in outpatients presenting with pleuritic chest pain.

Early Recognition of Pulmonary Embolism

Pulmonary embolism is a major cause of morbidity and mortality in the United States. The majority of deaths from pulmonary embolism occur because an accurate diagnosis was not made. It is imperative for clinicians to have a high level of clinical suspicion of pulmonary embolism when patients present with dyspnea, tachypnea, chest pain, hemoptysis, and cough. If pulmonary embolism is diagnosed and treatment initiated, death and recurrence of embolism are uncommon. Beyond correct diagnosis and treatment, the single most effective strategy that can be employed to decrease the high mortality associated with pulmonary embolism is identification of individuals at risk and the institution of prophylactic measures. This article reviews the incidence, risk factors, assessment, physical examination, laboratory, and diagnostic testing for pulmonary embolism.

The Impact of the Introduction of Computed Tomography With Pulmonary Angiography as a Diagnostic Test for Pulmonary Embolism

The Impact of the Introduction of Computed Tomography With Pulmonary Angiography as a Diagnostic Test for Pulmonary Embolism

Bedside Diagnostic Tests for Pulmonary Embolism

Bedside Diagnostic Tests for Pulmonary Embolism

Contrast-enhanced spiral computed tomography of the pulmonary arteries: an overview.

Spiral computed tomography is a new noninvasive diagnostic test for pulmonary embolism. The method provides tomographic images of the thorax in the axial plane, which depict the thoracic wall, the mediastinum, the lungs, and the pulmonary vessels. Thrombotic emboli in the vessels are seen as intraluminal filling defects in the contrast-enhanced pulmonary arteries. The physical principles of spiral computed tomography and several technical considerations concerning image quality will be briefly discussed. The accuracy of spiral computed tomography in the detection of pulmonary embolism is discussed by way of an overview of published validation and clinical outcome studies encompassing spiral computed tomography and the diagnosis of pulmonary embolism.

Effects of age on the performance of common diagnostic tests for pulmonary embolism

PURPOSE: The diagnosis of pulmonary embolism in the elderly is often difficult because of comorbid medical conditions, and perhaps also because diagnostic tests have a lower yield. We analyzed the diagnostic performance of common diagnostic tests for pulmonary embolism in different age groups. METHODS: We analyzed data from two large studies that enrolled 1,029 consecutive patients presenting to the emergency department with clinically suspected pulmonary embolism. The clinical probability of pulmonary embolism (high [≥80%], intermediate, or low [≤20%]) was estimated by the treating physician. All patients underwent a sequential diagnostic protocol, including ventilation-perfusion lung scan, measurement of plasma D-dimer level, lower limb venous compression ultrasonography, and pulmonary angiography if the noninvasive work-up was inconclusive. RESULTS: The prevalence of pulmonary embolism increased progressively, from 12% in patients <40 years of age to 44% in those ≥80 years of age. The positive predictive value of a high clinical probability of pulmonary embolism was greater in the elderly (71% to 78% in those ≥60 years old versus 40% to 64% in those ≤59 years old). The sensitivity of D-dimer testing was 100% in all age groups, but its specificity decreased markedly with age, from 67% in those ≤40 years old to 10% in those ≥80 years old. The diagnostic yield of lower limb compression ultrasonography was greater in the elderly. The proportion of lung scans that were diagnostic (normal, near-normal, or high probability) decreased from 68% to 42% with increasing age. CONCLUSIONS: Age affects the performance of common diagnostic tests for pulmonary embolism and should be kept in mind when evaluating patients suspected of having this condition.

Acute pulmonary embolism

Acute pulmonary embolism

THE DIAGNOSIS OF PULMONARY EMBOLISM.

No single noninvasive test for pulmonary embolism is both sensitive and specific. Some tests are good for "ruling in" pulmonary embolism (e.g., helical CT) and some tests are good for "ruling out" pulmonary embolism (e.g., D-dimer); others are able to do both but are often nondiagnostic (e.g., ventilation-perfusion lung scanning). For optimal efficiency, choice of the initial diagnostic test should be guided by clinical assessment of the probability of pulmonary embolism and by patient characteristics that may influence test accuracy. This selective approach to testing enables pulmonary embolism to be diagnosed or excluded in a minimum number of steps. However, even with the appropriate use of combinations of noninvasive tests, it is often not possible to definitively diagnose or exclude pulmonary embolism at initial presentation. Most of these patients can be managed safely without treatment or pulmonary angiography by repeating ultrasound testing of the proximal veins after one and 2 weeks to detect evolving deep vein thrombosis. Helical CT and MRI are rapidly improving as diagnostic tests for pulmonary embolism and are expected to become central to its evaluation.