Clinical prediction rules for pulmonary embolism: a systematic review and meta-analysis

Intermediate-Risk and High-Risk Pulmonary Embolism: Recognition and Management: Cardiology Clinics: Cardiac Emergencies

Pulmonary embolism (PE) is the third most common cause of cardiovascular death. Every specialty of medical practitioner will encounter PE in their patients, and should be prepared to employ contemporary strategies for diagnosis and initial risk-stratification. Treatment of PE is based on risk-stratification, with anticoagulation for all patients, and advanced modalities including systemic thrombolysis, catheter-directed therapies, and mechanical circulatory supports utilized in a manner paralleling PE severity and clinical context.

Ten-Year Trend in Advanced Imaging Utilization for Suspected Pulmonary Embolism in Pregnancy

PURPOSE

Advanced imaging is essential to diagnose pulmonary embolism (PE) in pregnancy, but there are associated maternal and fetal radiation risks. The purpose of this study was to evaluate the 10-year trend in advanced imaging utilization for the evaluation of suspected PE in pregnancy.

METHODS

The authors evaluated pregnant women with advanced imaging using CT pulmonary angiography (CTPA) or lung scintigraphy (LS) for evaluation of suspected PE presenting to two tertiary hospitals from 2007 to 2016. The rate of imaging was evaluated relative to positive PE rate and local pregnancy rate. positive PE was defined as a new acute PE finding on any advanced imaging within 3 days of first advanced imaging test. Local pregnancy rates were defined per 1,000 pregnancies in the county serviced by both hospitals. Chi-square testing was used to evaluate statistical significance (P < .05) in the utilization trend of advanced imaging and relative to local pregnancy rates and evaluations positive for PE.

RESULTS

A total of 707 pregnant patients were identified, of whom 92.5% (n = 654) underwent CTPA and 7.5% (n = 53) underwent LS. Regression analysis showed an average increase of 5.2 advanced imaging studies per year (P < .001), with 61 and 105 studies performed in 2007 and 2016, respectively. Additionally, there was an average increase of 0.08 (P < .001) advanced imaging studies per 1,000 local pregnancies per year, doubling from 0.7 in 2007 to 1.4 in 2016 (P < .001). Finally, there was a decrease of 0.004 (P = .009) in advanced imaging positive for PE, from 3% (2 of 61) in 2007 to 0% (0 of 100) in 2016.

CONCLUSIONS

Advanced imaging utilization increased by 72% over the 10-year window, driven by higher use of CTPA. Although the detection rate of PE on advanced imaging has decreased, the utilization rate among pregnant patients doubled during this period. These results highlight the need to consider the radiation risks and costs of advanced imaging in specific patient populations.

A machine learning model for diagnosing acute pulmonary embolism and comparison with Wells score, revised Geneva score, and Years algorithm

BACKGROUND

Acute pulmonary embolism (APE) is a fatal cardiovascular disease, yet missed diagnosis and misdiagnosis often occur due to non-specific symptoms and signs. A simple, objective technique will help clinicians make a quick and precise diagnosis. In population studies, machine learning (ML) plays a critical role in characterizing cardiovascular risks, predicting outcomes, and identifying biomarkers. This work sought to develop an ML model for helping APE diagnosis and compare it against current clinical probability assessment models.

METHODS

This is a single-center retrospective study. Patients with suspected APE were continuously enrolled and randomly divided into two groups including training and testing sets. A total of 8 ML models, including random forest (RF), Naïve Bayes, decision tree, K-nearest neighbors, logistic regression, multi-layer perceptron, support vector machine, and gradient boosting decision tree were developed based on the training set to diagnose APE. Thereafter, the model with the best diagnostic performance was selected and evaluated against the current clinical assessment strategies, including the Wells score, revised Geneva score, and Years algorithm. Eventually, the ML model was internally validated to assess the diagnostic performance using receiver operating characteristic (ROC) analysis.

RESULTS

The ML models were constructed using eight clinical features, including D-dimer, cardiac troponin T (cTNT), arterial oxygen saturation, heart rate, chest pain, lower limb pain, hemoptysis, and chronic heart failure. Among eight ML models, the RF model achieved the best performance with the highest area under the curve (AUC) (AUC = 0.774). Compared to the current clinical assessment strategies, the RF model outperformed the Wells score ( P = 0.030) and was not inferior to any other clinical probability assessment strategy. The AUC of the RF model for diagnosing APE onset in internal validation set was 0.726.

CONCLUSIONS

Based on RF algorithm, a novel prediction model was finally constructed for APE diagnosis. When compared to the current clinical assessment strategies, the RF model achieved better diagnostic efficacy and accuracy. Therefore, the ML algorithm can be a useful tool in assisting with the diagnosis of APE.

How to recognize pulmonary embolism in syncope patients: A simple rule

BACKGROUND

Syncope can be the presenting symptom of Pulmonary Embolism (PE). It is not known wether using a standardized algorithm to rule-out PE in all patients with syncope admitted to the Emergency Departments (ED) is of value or can lead to overdiagnosis and overtreatment.

METHODS

We tested if simple anamnestic and clinical parameters could be used as a rule to identify patients with syncope and PE in a multicenter observational study. The rule's sensitivity was tested on a cohort of patients that presented to the ED for syncopal episodes caused by PE. The clinical impact of the rule was assessed on a population of consecutive patients admitted for syncope in the ED.

RESULTS

Patients were considered rule-positive in the presence of any of the following: hypotension, tachycardia, peripheral oxygen saturation ≤ 93 % (SpO2), chest pain, dyspnea, recent history of prolonged bed rest, clinical signs of deep vein thrombosis, history of previous venous thrombo-embolism and active neoplastic disease. The sensitivity of the rule was 90.3 % (95 % CI: 74.3 % to 98.0 %). The application of the rule to a population of 217 patients with syncope would have led to a 70 % reduction in the number of subjects needing additional diagnostic tests to exclude PE.

CONCLUSIONS

Most patients with syncope due to PE present with anamnestic and clinical features indicative of PE diagnosis. A clinical decision rule can be used to identify patients who would benefit from further diagnostic tests to exclude PE, while reducing unnecessary exams that could lead to over-testing and over-diagnosis.

Clinical prediction tool to identify children at risk of pulmonary embolism

INTRODUCTION

The diagnosis of pediatric pulmonary embolism (PE) is often delayed due to non-specific symptoms, and clinical prediction tools designed for adults are unsuitable for children. This study aimed to create a PE predictive model and to evaluate the reported tools in the Thai pediatric population.

MATERIALS AND METHODS

A multi-center retrospective study from 4 university hospitals included children ≤18 years of age undergoing computed tomography pulmonary angiogram from 2000 to 2020 with the suspicion of PE. Patients' clinical presentations and risk factors of venous thromboembolism (VTE) were compared between the PE-positive and PE-negative groups. Significant risk factors from univariate and multivariate logistic regression were included to create a clinical prediction tool. The performance of the model was demonstrated by sensitivity, specificity, area under the curve (AUC), Hosmer Lemeshow test, ratio of observed and expected outcomes and bootstrapping.

RESULTS

Of the 104 patients included, 43 (41.3 %) were grouped as PE-positive and 61 (58.7 %) as PE-negative. Five parameters, including congenital heart disease/pulmonary surgery, known thrombophilia, previous VTE, nephrotic syndrome and chest pain showed significant differences between the two groups. Score ≥ 2 yielded a 74.4 % sensitivity and a 75.4 % specificity with an AUC of the model of 0.809. The model performance and validation results were within satisfactory ranges.

CONCLUSION

The study created a clinical prediction tool indicating the likelihood of PE among Thai children. A score ≥2 was suggestive of PE.

High and intermediate risk pulmonary embolism in the ICU

Pulmonary embolism (PE) is a common and important medical emergency, encountered by clinicians across all acute care specialties. PE is a relatively uncommon cause of direct admission to the intensive care unit (ICU), but these patients are at high risk of death. More commonly, patients admitted to ICU develop PE as a complication of an unrelated acute illness. This paper reviews the epidemiology, diagnosis, risk stratification, and particularly the management of PE from a critical care perspective. Issues around prevention, anticoagulation, fibrinolysis, catheter-based techniques, surgical embolectomy, and extracorporeal support are discussed.

Deep vein thrombosis and pulmonary embolism: a prospective, observational study to evaluate diagnostic performance of the Tina-quant D-Dimer Gen.2 assay

Background

D-Dimer testing is a diagnostic tool for exclusion of deep vein thrombosis (DVT) and pulmonary embolism (PE). This study evaluated the diagnostic performance of the Tina-quant® D-Dimer Gen.2 assay (Roche Diagnostics International Ltd, Rotkreuz, Switzerland) in patients with low/intermediate pre-test probability of DVT/PE using standard, age-, and clinical probability-adjusted cut-offs.

Methods

In this prospective, observational, multicenter study (July 2017-August 2019), plasma samples were collected from hospital emergency departments and specialist referral centers. DVT/PE was diagnosed under hospital standard procedures and imaging protocols. A standard D-dimer cut-off of 0.5 µg fibrinogen equivalent units (FEU)/ml was combined with the three-level Wells score; cut-offs adjusted for age (age × 0.01 µg FEU/ml for patients >50 years) and clinical probability (1 µg FEU/ml for low probability) were also evaluated. An assay comparison was conducted in a subset of samples using the Tina-quant D-Dimer Gen.2 assay and the previously established routine laboratory assay, STA-Liatest D-Di Plus assay (Stago Deutschland GmbH, Düsseldorf, Germany).

Results

2,897 patients were enrolled; 2,516 completed the study (DVT cohort: 1,741 PE cohort: 775). Clinical assessment plus D-dimer testing using the standard cut-off resulted in 317 (DVT) and 230 (PE) false positives, and zero (DVT) and one (PE) false negatives. Negative predictive value (NPV) was 100.0% (95% confidence interval [CI]: 99.7%-100.0%) and 99.8% (95% CI: 98.8%-100.0%) for DVT and PE, respectively. After age-adjustment, NPV was 99.9% (95% CI: 99.6%-100.0%) and 99.1% (95% CI: 97.8-99.7) for DVT and PE, respectively. False positive rates decreased (>50%) in clinical probability-adjusted analyses vs. primary analysis. In the assay comparison, the performances of the two assays were comparable.

Conclusion

The Tina-quant D-Dimer Gen.2 assay and standard D-dimer cut-off level combined with the three-level Wells score accurately identified patients with a very low probability of DVT/PE.

Low Risk Meets High Stakes: Unraveling the Mystery of Low D-dimer Pulmonary Embolism

Pulmonary embolisms (PEs) are potentially life-threatening emergencies that carry significant morbidity and mortality. Advances in treatment options and the safety of existing procedures have effectively reduced the long-term and short-term effects of the condition. Therefore, it is important to make an early diagnosis so that treatment options can be thoroughly explored. The D-dimer is an important tool in the early diagnosis of PEs. It is especially useful in ruling out the diagnosis in patients with a low to moderate suspicion of the disease. We present a case of a 22-year-old male who presented with exertional dyspnea, congestion, and rhinorrhea for one day and was noted to have persistent hypoxia and tachycardia. The influenza test was positive, and he was started on oseltamivir. Due to persistent hypoxia, a CT pulmonary angiogram was ordered and revealed filling defects in the left lower lobe segmental vessels suggestive of PE, as well as multifocal multilobar bilateral ground-glass opacities. He was initially treated with a heparin drip and subsequently switched to eliquis. After a significant improvement in his hypoxia, he was discharged home for outpatient follow-up, including a hypercoagulable workup. This case demonstrates that despite the usefulness of the D-dimer as a diagnostic tool for PEs, it cannot solely or fully replace the full gamut of screening tools used to determine the risk of PE. Although rare, false-negative scores do occur; therefore, the tool should always be used in conjunction with other scoring systems, physician gestalt, and within the specific clinical context.

Comparison of international guideline recommendations for the diagnosis of pulmonary embolism

Pulmonary embolism is one of the leading causes of death due to cardiovascular disease. Timely diagnosis is crucial, but challenging, as the clinical presentation of pulmonary embolism is unspecific and easily mistaken for other common medical emergencies. Clinical prediction rules and D-dimer measurement allow stratification of patients into groups of expected prevalence and are key elements in adequate selection of patients for diagnostic imaging; however, the strengths and weaknesses of the multiple proposed prediction rules, when to measure D-dimer, and which cutoff to apply might be elusive to a significant proportion of physicians. 13 international guidelines authored by medical societies or expert author groups provide recommendations on facets of the diagnostic investigations in suspected pulmonary embolism, some of which are hallmarked by pronounced heterogeneity. This Review summarises key recommendations of each guideline, considers the most recent evidence on the topic, compares guideline recommendations on each facet of the diagnosis of pulmonary embolism, and provides a synthesis on the most common recommendations.

American Society of Hematology, ABHH, ACHO, Grupo CAHT, Grupo CLAHT, SAH, SBHH, SHU, SOCHIHEM, SOMETH, Sociedad Panamena de Hematología, Sociedad Peruana de Hematología, and SVH 2023 guidelines for diagnosis of venous thromboembolism and for its management in special populations in Latin America

Implementation of international guidelines in Latin American settings requires additional considerations (ie, values and preferences, resources, accessibility, feasibility, and impact on health equity). The purpose of this guideline is to provide evidence-based recommendations about the diagnosis of venous thromboembolism (VTE) and its management in children and during pregnancy. We used the GRADE ADOLOPMENT method to adapt recommendations from 3 American Society of Hematology (ASH) VTE guidelines (diagnosis of VTE, VTE in pregnancy, and VTE in the pediatric population). ASH and 12 local hematology societies formed a guideline panel comprising medical professionals from 10 countries in Latin America. Panelists prioritized 10 questions about the diagnosis of VTE and 18 questions about its management in special populations that were relevant for the Latin American context. A knowledge synthesis team updated evidence reviews of health effects conducted for the original ASH guidelines and summarized information about factors specific to the Latin American context. In comparison with the original guideline, there were significant changes in 2 of 10 diagnostic recommendations (changes in the diagnostic algorithms) and in 9 of 18 management recommendations (4 changed direction and 5 changed strength). This guideline ADOLOPMENT project highlighted the importance of contextualizing recommendations in other settings based on differences in values, resources, feasibility, and health equity impact.

Predictive value of D-dimer and fibrinogen degradation product for splanchnic vein thrombosis in patients with severe acute pancreatitis: a single-center retrospective study

BACKGROUND AND AIM

Early diagnosis of splanchnic vein thrombosis (SVT) after severe acute pancreatitis (SAP) remains difficult because of its insidious onset. Common serum markers for thrombosis such as D-dimer (D-D) have lost their diagnostic value due to their elevation in non-thrombotic patients with SAP. The aim of this study is to predict SVT after SAP using common serum indicators of thrombosis by establishing a new cut-off value.

METHODS

177 SAP patients were included in a retrospective cohort study from September 2019 to September 2021. Patient demographics, dynamic changes of coagulation and fibrinolysis indicators were collected. Univariate analyses and binary logistic regression analyses were applied to assess potential risk factors for the development of SVT in SAP patients. A receiver operating characteristic (ROC) curve was generated to assess the predictive value of independent risk factors. Moreover, clinical complications and outcomes were compared between two groups.

RESULTS

Among 177 SAP patients, 32 (18.1%) developed SVT. The most common cause of SAP was biliary (49.8%), followed by hypertriglyceridemia (21.5%). Multivariate logistic regression analyses showed that D-D (OR, 1.135; 95%CI, 1.043-1.236; p = 0.003) and fibrinogen degradation product (FDP) (OR, 1.037; 95%CI, 1.015-1.060; p = 0.001) were independent risk factors for SVT development in patients with SAP. The area under ROC curve for D-D was 0.891 (p = 0.003, sensitivity= 95.3%, specificity = 74.1%) at a cut-off value of 6.475, and the area under ROC curve for FDP was 0.858 (p = 0.001, sensitivity = 89.4%, specificity = 72.4%) at a cut-off value of 23.155.

CONCLUSION

D-D and FDP are significant independent risk factors with high predictive value for SVT in patients with SAP.

A Clinical Prediction Rule for Thrombosis in Critically Ill COVID-19 Patients: Step 1 Results of the Thromcco Study

The incidence of thrombosis in COVID-19 patients is exceptionally high among intensive care unit (ICU)-admitted individuals. We aimed to develop a clinical prediction rule for thrombosis in hospitalized COVID-19 patients. Data were taken from the Thromcco study (TS) database, which contains information on consecutive adults (aged ≥ 18) admitted to eight Spanish ICUs between March 2020 and October 2021. Diverse logistic regression model analysis, including demographic data, pre-existing conditions, and blood tests collected during the first 24 h of hospitalization, was performed to build a model that predicted thrombosis. Once obtained, the numeric and categorical variables considered were converted to factor variables giving them a score. Out of 2055 patients included in the TS database, 299 subjects with a median age of 62.4 years (IQR 51.5-70) (79% men) were considered in the final model (SE = 83%, SP = 62%, accuracy = 77%). Seven variables with assigned scores were delineated as age 25-40 and ≥70 = 12, age 41-70 = 13, male = 1, D-dimer ≥ 500 ng/mL = 13, leukocytes ≥ 10 × 10³/µL = 1, interleukin-6 ≥ 10 pg/mL = 1, and C-reactive protein (CRP) ≥ 50 mg/L = 1. Score values ≥28 had a sensitivity of 88% and specificity of 29% for thrombosis. This score could be helpful in recognizing patients at higher risk for thrombosis, but further research is needed.

Derivation and External Validation of a Risk Prediction Model for Pulmonary Embolism in Patients With Lung Cancer: A Large Retrospective Cohort Study

OBJECTIVE

To investigate the risk factors of pulmonary embolism in patients with lung cancer and develop and validate a novel nomogram scoring system-based prediction model.

METHOD

We retrospectively analyzed the clinical data and laboratory characteristics of 900 patients with lung cancer who were treated, including patients with lung cancer without pulmonary embolism (LC) and patients with lung cancer with pulmonary embolism (LC  +  PE). The patients were randomly divided into derivation and internal validation groups in a 7:3 ratio. Using logistic regression analysis, a diagnostic model of the nomogram scoring system was developed by incorporating selected variables in the derivation group and validated in the internal and external validation groups (n  =  108).

RESULT

Seven variables (adenocarcinoma, stage III-IV LC, indwelling central venous catheter, chemotherapy, and the levels of serum albumin, hemoglobin, and D-dimer) were identified as valuable parameters for developing the novel nomogram diagnostic model for differentiating patients with LC and LC  +  PE. The scoring system demonstrated good diagnostic performance in the derivation (area under the curve [AUC]; 95% confidence interval [CI], 0.918; 0.893, 0.943; sensitivity, 88.5%; specificity, 80.5%), internal validation (AUC; 95% CI, 0.921; 0.884, 0.958; sensitivity, 90.5%; specificity, 80.4%), and external validation (AUC; 95% CI, 0.929; 0.875, 0.983; sensitivity; 85.0%; specificity; 87.5%) groups.

CONCLUSION

In this study, we constructed and validated a nomogram scoring system based on 7 clinical parameters. The scoring system exhibits good accuracy and discrimination between patients with LC and LC  +  PE and can effectively predict the risk of PE in patients with LC.

Diagnostic Accuracy of a Bespoke Multiorgan Ultrasound Approach in Suspected Pulmonary Embolism

Purpose The aims of this study were to prospectively assess the diagnostic accuracy of a bespoke multiorgan point-of-care ultrasound approach for suspected pulmonary embolism and evaluate if this model allows reduced referral to further radiation diagnostics while maintaining safety standards. Materials and Methods Patients with suspected pulmonary embolism referred for CT pulmonary angiography or ventilation/perfusion scintigraphy were included as a convenience sample. All patients were subject to blinded ultrasound investigation with cardiac, lung, and deep venous ultrasound. The sensitivity and specificity of applied ultrasound signs and the hypothetical reduction in the need for further diagnostic workup were calculated. Results 75 patients were prospectively enrolled. The Wells score was below 2 in 48 patients, between 2 and 6 in 24 patients, and above 6 in 3 patients. The prevalence of pulmonary embolism was 28%. The most notable ultrasound signs were presence of a deep venous thrombus, at least two hypoechoic pleural-based lesions, the D-sign, the 60/60-sign, and a visible right ventricular thrombus which all had a specificity of 100%. Additionally, a multiorgan ultrasound investigation with no findings compatible with pulmonary embolism yielded a sensitivity of 95.2% (95%CI: 76.2-99.9). CT or scintigraphy could be safely avoided in 70% of cases (95%CI: 63.0-83.1%). Conclusion The findings of our study suggest that implementation of a multiorgan ultrasound assessment in patients with suspected pulmonary embolism may safely reduce the need for CT or scintigraphy by confirming or dismissing the suspicion.

COVID-19 infection and its impact on case fatality in patients with pulmonary embolism

BACKGROUND

Although a high prevalence of pulmonary embolism (PE) has been reported in association with coronavirus disease 2019 (COVID-19) in critically ill patients, nationwide data on the outcome of hospitalised patients with COVID-19 and PE are still limited. Thus, we investigated seasonal trends and predictors of in-hospital death in patients with COVID-19 and PE in Germany.

METHODS

We used a German nationwide inpatient sample to analyse data on hospitalisations among COVID-19 patients with and without PE during 2020, and to detect changes in PE prevalence and case fatality in comparison with 2019.

RESULTS

We analysed 176 137 COVID-19 hospitalisations in 2020; PE was recorded in 1.9% (n=3362) of discharge certificates. Almost one-third of patients with COVID-19 and PE died during the in-hospital course (28.7%) compared with COVID-19 patients without PE (17.7%). Between 2019 and 2020, numbers of PE-related hospitalisations were largely unchanged (98 485 versus 97 718), whereas the case fatality rate of PE increased slightly in 2020 (from 12.7% to 13.1%; p<0.001). Differences in case fatality were found between PE patients with and without COVID-19 in 2020 (28.7% versus 12.5%; p<0.001), corresponding to a 3.1-fold increased risk of PE-related death (OR 3.16, 95% CI 2.91-3.42; p<0.001) in the presence of COVID-19.

CONCLUSIONS

In Germany, the prevalence of PE events during hospitalisations was similar in 2019 and 2020. However, the fatality rate among patients with both COVID-19 and PE was substantially higher than that in those with only one of these diseases, suggesting a life-threatening additive prognostic impact of the COVID-19-PE combination.

PrEdictive value of coMbined pre-test proBability and blOod gas anaLysis In pulmonary emboliSM-the EMBOLISM study

In patients with suspected pulmonary embolism (PE), the number of unnecessary computed tomography pulmonary angiography (CTPA) scans remains high, especially in patients with low pre-test probability (PTP). So far, no study showed any additional benefit of capillary blood gas analysis (BGA) in diagnostic algorithms for PE. In this retrospective analysis of patients with suspected PE and subsequent CTPA, clinical data, D-dimer levels and BGA parameters (including standardized PaO2) were analyzed. Logistic regression analyses were performed to identify independent predictors for PE and reduce unnecessary CTPA examinations in patients with low PTP according to Wells score. Of 1538 patients, PE was diagnosed in 433 patients (28.2%). The original Wells score (odds ratio: 1.381 [95% CI 1.300-1.467], p < 0.001) and standardized PaO2 (odds ratio: 0.987 [95% CI 0.978-0.996], p = 0.005) were independent predictors for PE. After cohort adjustment for low PTP a D-dimer cut-off < 1.5 mg/L (278 patients (18.1%) with 18 PE (6.5%)) was identified in which a standardized PaO2 > 65 mmHg reduced the number of unnecessary CTPA by 31.9% with a 100% sensitivity. This approach was further validated in additional 53 patients with low PTP. In this validation group CTPA examinations were reduced by 32.7%. No patient with PE was missed. With our novel algorithm combining BGA testing with low PTP according to Wells score, we were able to increase the D-Dimer threshold to 1.5 mg/L and reduce CTPA examinations by approximately 32%.

Elevation of the D-dimer cut-off level might be applicable to rule out pulmonary embolism for active cancer patients in the emergency department

Recent guidelines for diagnosing acute pulmonary embolism (PE) are based on clinical decision rules and D-dimer. D-dimer measurement is recommended only for patients who are 'PE-unlikely'. We aimed to assess the current guidelines for cancer patients and to determine an optimal D-dimer cut-off level. This retrospective observational study was conducted in the emergency department of Asan Medical Center (Seoul, Korea) between 02/2017 and 09/2017 for the development cohort and between 06/2018 and 02/2019 for the validation cohort. Among adult active cancer patients with suspected PE, we included those who were 'PE-unlikely' according to Wells' criteria and who underwent D-dimer testing and computed tomographic pulmonary angiography (CTPA). A total of 498 patients (227 in the development cohort and 271 in the validation cohort) were included, and PE was diagnosed in 8.8% and 18.5% of patients, respectively. The optimal D-dimer cut-off level was 2.0 μg/mL. This elevated cut-off level showed a much higher specificity of 21.3% (95% confidence interval [CI] 16.2-27.3%) and 21.7% (95% CI 16.8-7.6%) in the development and validation sets, respectively, compared with the specificity of 4.4% (95% CI 2.3-8.1%) and 4.1% (95% CI 2.2-7.6%) using the age-adjusted cut-off. The new D-dimer cut-off value identified unnecessary CTPA for 21.3% of patients (absolute difference, 16.9%, 35 of 207) in the development cohort and 21.7% (absolute difference, 17.6%, 39 of 221) of patients in the validation cohort compared to using the standard age-adjusted cut-off. The elevated D-dimer cut-off value combined with Wells' criteria might reduce unnecessary CTPA in active cancer patients with a 'PE-unlikely' classification. Further clinical trials are warranted to improve the PE diagnostic strategy in cancer patients.

Echocardiographic findings in patients with acute pulmonary embolism at Sohag University Hospitals

Background

Acute pulmonary thromboembolism (PTE) is one of the serious medical issues with higher prevalence and mortality rates. As mentioned in several medical reports, most of the chest pain patients, visiting the emergency departments, are usually diagnosed with either acute PTE, acute coronary syndromes, or acute aortic syndromes. The current study aimed to study the risk factors and explore the echocardiographic findings in patients with PTE.

Results

Forty patients with acute pulmonary embolism were enrolled in the study. Echocardiography and computed tomography pulmonary angiography (CTPA) were evaluated for all participants. The echocardiography showed that 29 patients (72.5%) had echocardiographic findings suggestive of acute PTE. Twenty-four patients (60%) had tricuspid regurge. Twenty-one patients (52.5%) had dilated right ventricle (RV). Also, 13 patients (32.5%) had an echocardiographic finding of pulmonary hypertension. Furthermore, ten patients (25%) had McConnell’s sign, and 21 patients (52.5%) had RV systolic dysfunction where only two (5%) showed RV thrombosis. Echocardiographic data of the eight high-risk patients showed that 6 patients (75%) had TR, 8 patients (100%) had dilated RV, 5 patients (62.5%) had pulmonary hypertension, 8 patients (100%) had McConnell’s sign, one patient (12.5%) had RV thrombus, and 8 patients (100%) had RV systolic dysfunction.

Conclusion

The results revealed that thrombus in the main pulmonary trunk was a high-risk factor for patients with acute pulmonary embolism. The current study suggested that echocardiography is an important bedside imaging tool for the diagnosis of PTE. Echocardiography could detect the tricuspid regurge, pulmonary hypertension, McConnell’s sign, RV dilatation, thrombosis, and dysfunction. Furthermore, echocardiography was considered a non-invasive test for rapid diagnosis of PTE and determining the degree of the risk category (high- or low-risk patients) specially with the presence of McConnell’s sign, dilated RV, and RV systolic dysfunction.

Elderly Population with COVID-19 and the Accuracy of Clinical Scales and D-Dimer for Pulmonary Embolism: The OCTA-COVID Study

BACKGROUND

Elderly COVID-19 patients have a high risk of pulmonary embolism (PE), but factors that predict PE are unknown in this population. This study assessed the Wells and revised Geneva scoring systems as predictors of PE and their relationships with D-dimer (DD) in this population.

METHODS

This was a longitudinal, observational study that included patients ≥75 years old with COVID-19 and suspected PE. The performances of the Wells score, revised Geneva score and DD levels were assessed. The combinations of the DD level and the clinical scales were evaluated using positive rules for higher specificity.

RESULTS

Among 305 patients included in the OCTA-COVID study cohort, 50 had suspected PE based on computed tomography pulmonary arteriography (CTPA), and the prevalence was 5.6%. The frequencies of PE in the low-, intermediate- and high-probability categories were 5.9%, 88.2% and 5.9% for the Geneva model and 35.3%, 58.8% and 5.9% for the Wells model, respectively. The DD median was higher in the PE group (4.33 mg/L; interquartile range (IQR) 2.40-7.17) than in the no PE group (1.39 mg/L; IQR 1.01-2.75) (p < 0.001). The area under the curve (AUC) for DD was 0.789 (0.652-0.927). After changing the cutoff point for DD to 4.33 mg/L, the specificity increased from 42.5% to 93.9%.

CONCLUSIONS

The cutoff point DD > 4.33 mg/L has an increased specificity, which can discriminate false positives. The addition of the DD and the clinical probability scales increases the specificity and negative predictive value, which helps to avoid unnecessary invasive tests in this population.

D-Dimer Tests in the Emergency Department: Current Insights

In the Emergency Medicine setting, D-dimer is currently employed in the diagnostic assessment of suspected venous thromboembolism and aortic syndrome. The nonspecific symptoms reported by patients, like chest pain, dyspnea or syncope, uncover a wide range of differential diagnosis, spanning from mild to life-threatening conditions. Therefore, we assumed the perspective of the Emergency Physician and, in this narrative review, we reported a brief presentation of the epidemiology of these symptoms and the characteristics of patients, in whom we could suspect the aforementioned pathologies. We also reported in which patients D-dimer gives useful information. In fact, when the probability of the disease is high, the D-dimer level is futile. On the contrary, given the low specificity of the test, when the probability of the disease is very low, a false-positive value of the D-dimer only increases the risk of overtesting. Patients with low to moderate probability really benefit from the D-dimer testing, in order to prevent the execution of expensive and potentially dangerous imaging tests. In the second part of the review, we focused on the prognostic value of the test in septic patients. The early prognostic stratification of septic patients remains a challenge for the Emergency Physician, in the absence of a definite biomarker or score to rely on. Therefore, we need several parameters for the early identification of patients at risk of an adverse prognosis and the D-dimer may play a role in this demanding task. SARS COVID-19 patients represent an emerging reality, where the role of the D-dimer for prognostic stratification could be relevant. In fact, in patients with severe forms of this disease, the D-dimer reaches very high values, which appear to parallel the course of respiratory failure. Whether the test may add useful information for the management of these patients remains to be determined.

D-dimer to rule out venous thromboembolism during pregnancy: A systematic review and meta-analysis

BACKGROUND

The usefulness of D-dimer measurement to rule out venous thromboembolism (VTE) during pregnancy is debated.

OBJECTIVES

We performed a systematic review and meta-analysis to investigate the safety of D-dimer to rule out acute VTE in pregnant women with suspected pulmonary embolism and/or deep vein thrombosis.

METHODS

Two reviewers independently identified studies through PubMed and Embase until June 2021, week 1. We supplemented our search by manually reviewing reference lists of all retrieved articles, clinicalTrials.gov, and reference literature. Prospective or retrospective studies in which a formal diagnostic algorithm was used to evaluate the ability of D-dimer to rule out VTE during pregnancy were eligible.

RESULTS

We identified 665 references through systematic database and additional search strategies; 45 studies were retrieved in full, of which four were included, after applying exclusion criteria. Three studies were prospective, and one had a retrospective design. The 3-month thromboembolic rate in pregnant women left untreated after a negative D-dimer was 1/312 (0.32%; 95% CI, 0.06-1.83). The pooled estimate values were 99.5% for sensitivity (95% CI, 95.0-100.0; I², 0%) and 100% for negative predictive value (95% CI, 99.19-100.0; I², 0%). The prevalence of VTE and the yield of D-dimer were 7.4% (95% CI, 3.8-12; I², 83%) and 34.2% (95% CI, 15.9-55.23; I², 89%) respectively.

CONCLUSION

Our results suggest that D-dimer allows to safely rule out VTE in pregnant women with suspected VTE and a disease prevalence consistent with a low/intermediate or unlikely pretest probability.

Risk factors for pulmonary embolism in patients with COVID-19: a systemic review and meta-analysis

PURPOSE

To detect the risk factors for pulmonary embolism (PE) in patients with COVID-19.

METHODS

Studies were searched for in PubMed, Cochrane Library, Web of Science, and EMBASE. Two authors independently screened articles and extracted data. The data were pooled by meta-analysis and three subgroup analyses were performed.

RESULTS

Of the 2210 articles identified, 27 studies were included. Pooled analysis suggested that males (odds ratio (OR) 1.49, 95% confidence interval (CI) 1.26-1.75, P = 0.000), obesity (OR 1.37, 95% CI 1.03-1.82, P = 0.033), mechanical ventilation (OR 3.34, 95% CI 1.90-5.86, P = 0.000), severe parenchymal abnormalities (OR 1.92, 95% CI 1.43-2.58, P = 0.000), ICU admission (OR 2.44, 95% CI 1.48-4.03, P = 0.000), and elevated D-dimer and white blood cell values (at two time points: hospital admission or closest to computed tomography pulmonary angiography) (P = 0.000) correlated with a risk for PE occurrence in COVID-19 patients. However, age and common comorbidities had no association with PE occurrence. Computed tomography pulmonary angiography, unclear-ratio/low-ratio, and hospitalization subgroups had consistent risk factors with all studies; however, other subgroups had fewer risk factors for PE.

CONCLUSIONS

Risk factors for PE in COVID-19 were different from the classic risk factors for PE and are likely to differ in diverse study populations.

Construction of a Risk Prediction Model for Hospital-Acquired Pulmonary Embolism in Hospitalized Patients

The purpose of this study is to establish a novel pulmonary embolism (PE) risk prediction model based on machine learning (ML) methods and to evaluate the predictive performance of the model and the contribution of variables to the predictive performance. We conducted a retrospective study at the Shanghai Tenth People's Hospital and collected the clinical data of in-patients that received pulmonary computed tomography imaging between January 1, 2014 and December 31, 2018. We trained several ML models, including logistic regression (LR), support vector machine (SVM), random forest (RF), and gradient boosting decision tree (GBDT), compared the models with representative baseline algorithms, and investigated their predictability and feature interpretation. A total of 3619 patients were included in the study. We discovered that the GBDT model demonstrated the best prediction with an area under the curve value of 0.799, whereas those of the RF, LR, and SVM models were 0.791, 0.716, and 0.743, respectively. The sensibilities of the GBDT, LR, RF, and SVM models were 63.9%, 68.1%, 71.5%, and 75%, respectively; the specificities were 81.1%, 66.1, 72.7%, and 65.1%, respectively; and the accuracies were 77.8%, 66.5%, 72.5%, and 67%, respectively. We discovered that the maximum D-dimer level contributed the most to the outcome prediction, followed by the extreme growth rate of the plasma fibrinogen level, in-hospital duration, and extreme growth rate of the D-dimer level. The study demonstrates the superiority of the GBDT model in predicting the risk of PE in hospitalized patients. However, in order to be applied in clinical practice and provide support for clinical decision-making, the predictive performance of the model needs to be prospectively verified.

Which adults with sickle cell disease need an evaluation for pulmonary embolism?

Individuals living with sickle cell disease (SCD) are at an increased risk of venous thrombo-embolism (VTE) including pulmonary embolisms (PEs). There is a high mortality associated with PE in individuals with SCD. It can be difficult to diagnose PE since presenting symptoms of PE often mimic those of other forms of vaso-occlusive crisis in SCD. Currently, there are no validated models for predicting PEs in patients with sickle cell disease, which often leads to frequent CT scans and exposure to harmful radiation and intravenous contrast. The aim of this study was to evaluate different host variables and potential clinical biomarkers of patients with SCD including those used in the Wells score to assess predictability for PE in order to create a more accurate diagnostic algorithm to predict PE. A retrospective chart review was performed on 349 patients with SCD who underwent testing for a PE with a CT scan of the chest. Forward and backward stepwise model selection was performed to obtain a parsimonious model of the predictors of PEs. The incidence of PE in this population was 9·7%. Of the factors evaluated for this study, the Wells score was the only one with clinical significance. A Wells score greater than 4 had a sensitivity and specificity of 72·5% and 70·1%, respectively, and a score greater than 6 had a sensitivity and specificity of 50% and 87%, respectively. The Wells score is an acceptable clinical tool which may prove useful in individuals with SCD to predict who is most likely to have a PE and therefore should undergo a CT scan. A prospective study is needed to further confirm these findings.

Decision support for computed tomography in the emergency department: a multicenter cluster-randomized controlled trial

OBJECTIVES

Clinical decision support may facilitate evidence-based imaging, but most studies to date examining the impact of decision support have used non-randomized designs which limit the conclusions that can be drawn from them. This randomized trial examines if decision support can reduce computed tomography (CT) utilization for patients with mild traumatic brain injuries and suspected pulmonary embolism in the emergency department. This study was funded by a competitive public research grant and registered on ClinicalTrials.gov (NCT02410941).

METHODS

Emergency physicians at five urban sites were assigned to voluntary decision support for CT imaging of patients with either head injuries or suspected pulmonary embolism using a cluster-randomized design over a 1-year intervention period. The co-primary outcomes were CT head and CT pulmonary angiography utilization. CT pulmonary angiography diagnostic yield (proportion of studies diagnostic for acute pulmonary embolism) was a secondary outcome.

RESULTS

A total of 225 physicians were randomized and studied over a 2-year baseline and 1-year intervention period. Physicians interacted with the decision support in 38.0% and 45.0% of eligible head injury and suspected pulmonary embolism cases, respectively. A mixed effects logistic regression model demonstrated no significant impact of decision support on head CT utilization (OR 0.93, 95% CI 0.79-1.10, p = 0.31), CT pulmonary angiography utilization (OR 0.98, 95% CI 0.88-1.11, p = 0.74) or diagnostic yield (OR 1.23, 95% CI 0.96-1.65, p = 0.10). However, overall CT pulmonary diagnostic yield (17.7%) was almost three times higher than that reported by a recent large US study, suggesting that selective imaging was already being employed.

CONCLUSION

Voluntary decision support addressing many commonly cited barriers to evidence-based imaging did not significantly reduce CT utilization or improve diagnostic yield but was limited by low rates of participation and high baseline rates of selective imaging. Demonstrating value to clinicians through interventions that improve workflow is likely necessary to meaningfully change imaging practices.

Risk stratification of emergency department patients with acute pulmonary thromboembolism: Is chest pain a reason to investigate?

BACKGROUND

This study aimed to risk-stratify chest pain as a presenting symptom in patients with a diagnosis of pulmonary thromboembolism (PE) to assess for any association. In addition, this study aimed to assess traditionally acknowledged PE risk factors in an Australian population.

METHODS

This was a retrospective single-centre cohort study assessing patients who presented to our emergency department during the period of 1 January 2019 to 1 January 2020. 730 consecutive patients who went on to computed tomography pulmonary angiography (CTPA) examination after presentation were included.

RESULTS

The rate of CTPA being positive in this study was 11.6% (85/730). Chest pain was associated with a non-significant reduction in the odds of PE (OR 0.774, P = 0.327). Univariate analysis showed significantly increased odds of a diagnosis of PE with presentation for leg pain/swelling (OR 6.670, P < 0.001). Multivariate analysis showed increasing age (OR 1.018, 95% CI 1.002-1.034, P = 0.024), clinical signs of a DVT (OR 3.194, 95% CI 1.803-5.657, P < 0.001) and positive D-dimer (OR 1.762, 95% CI 1.011-3.071, P = 0.046) were associated with increased odds of PE.

CONCLUSION

In this study, Emergency Department presentation with chest pain, whilst the most common reason to perform a CTPA, resulted in reduced odds with regard to the diagnosis of pulmonary thromboembolism. The use of CTPA in this setting may be rationalised according to other factors such as localised leg pain as a symptom, signs of DVT, increasing age or positive D-dimer.

The role of imaging in pulmonary hypertension

Pulmonary hypertension (PH) is a debilitating and potentially life threatening condition in which increased pressure in the pulmonary arteries may result from a variety of pathological processes. These can include disease primarily involving the pulmonary vasculature, but more commonly PH may result from left-sided heart disease, including valvular heart disease. Chronic thromboembolic pulmonary hypertension (CTEPH) is an important disease to identify because it may be amenable to surgical pulmonary artery endarterectomy or balloon pulmonary angioplasty. Parenchymal lung diseases are also widespread in the community. Any of these disease processes may result in adverse remodeling of the right ventricle and progressive right heart (RH) failure as a common final pathway. Because of the breadth of pathological processes which cause PH, multiple imaging modalities play vital roles in ensuring accurate diagnosis and classification, which will lead to application of the most appropriate therapy. Multimodality imaging may also provide important prognostic information and has a role in the assessment of response to therapies which ultimately dictate clinical outcomes. This review provides an overview of the wide variety of established imaging techniques currently in use, but also examines many of the novel imaging techniques which may be increasingly utilized in the future to guide comprehensive care of patients with PH.

Systematic review and meta-analysis of test accuracy for the diagnosis of suspected pulmonary embolism

Pulmonary embolism (PE) is a common, potentially life-threatening yet treatable condition. Prompt diagnosis and expeditious therapeutic intervention is of paramount importance for optimal patient management. Our objective was to systematically review the accuracy of D-dimer assay, compression ultrasonography (CUS), computed tomography pulmonary angiography (CTPA), and ventilation-perfusion (V/Q) scanning for the diagnosis of suspected first and recurrent PE. We searched Cochrane Central, MEDLINE, and EMBASE for eligible studies, reference lists of relevant reviews, registered trials, and relevant conference proceedings. 2 investigators screened and abstracted data. Risk of bias was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 and certainty of evidence using the Grading of Recommendations Assessment, Development and Evaluation framework. We pooled estimates of sensitivity and specificity. The review included 61 studies. The pooled estimates for D-dimer sensitivity and specificity were 0.97 (95% confidence interval [CI], 0.96-0.98) and 0.41 (95% CI, 0.36-0.46) respectively, whereas CTPA sensitivity and specificity were 0.94 (95% CI, 0.89-0.97) and 0.98 (95% CI, 0.97-0.99), respectively, and CUS sensitivity and specificity were 0.49 (95% CI, 0.31-0.66) and 0.96 (95% CI, 0.95-0.98), respectively. Three variations of pooled estimates for sensitivity and specificity of V/Q scan were carried out, based on interpretation of test results. D-dimer had the highest sensitivity when compared with imaging. CTPA and V/Q scans (high probability scan as a positive and low/non-diagnostic/normal scan as negative) both had the highest specificity. This systematic review was registered on PROSPERO as CRD42018084669.

COVID-19 and venous thromboembolism: Known and unknown for imaging decisions

As we continue to fight against the current coronavirus disease-2019 (COVID-19) pandemic, healthcare professionals across the globe are trying to answer questions surrounding how to best help patients with the up-to-date available science while awaiting the development of new therapies and mass vaccination. Since early in the pandemic, studies indicated a heightened risk of venous thromboembolism (VTE) in COVID-19 infected patients. There have been differing expert opinions about how to assess pretest probability of VTE in this patient population. This has been partly due to the high prevalence of respiratory failure in this patient population and the use of D-dimer as a prognostic test which is also frequently elevated in patients with COVID-19 in absence of VTE. Some experts have argued for an approach similar to usual care with testing if clinical suspicion is high enough. Some have argued for more routine screening at different points of care. Others have even suggested empiric therapeutic anti-coagulation in moderate to severely ill COVID-19 patients. In the following article, we review and summarize the most current literature in hopes of assisting clinicians in decision making and guidance for when to be concerned for VTE in COVID-19 patients. We also discuss research gaps and share pathways currently being used within our institution.

Echopulmonography as a Surrogate Modality in Disclosure of Occult Pulmonary Consequences of Pulmonary Vascular Occlusion

Background:

Diagnostic modalities of pulmonary embolism (PE) are still emerging day after day with new tools and promising characteristic features.

Objective:

The aim of our work was to assess the diagnostic yield of echopulmonography in patients with PE regarding pleural, parenchymal and vascular features of acute events and consequences.

Methods:

This is a prospective quasi-experimental study in which transthoracic echopulmonography was adopted as a screening method for patients with clinical suspicion of PE in comparison to Multi-Detector Computed Tomography Angiography of the chest, which is the best standard. This study was conducted on 32 patients at the chest department in Mansoura University Hospital and a Specialized Internal Medicine Hospital.

Results:

Echopulmonography was positive for pulmonary embolism at 68.75% but was of negative value in 31.25%. On the other hand, CTPA was positive for pulmonary embolism in (71.78%) but was of negative value in 28.12%. EPG confirm PE in 87% of patients diagnosed with PE by CTPA with a false-negative result of 13%. EPG could exclude PE in 77.7% of patients who were negative for PE by CTPA with a false-positive result of 22.2%.

Conclusion:

Echopulmonography might show promising features to be a substitute for computed tomography angiography in the diagnosis of pulmonary embolism.

Diagnostic management of inpatients with a positive D-dimer test: developing a new clinical decision-making rule for pulmonary embolism

Background

A positive D-dimer test has high sensitivity but relatively poor specificity for the diagnosis of pulmonary embolism, causing difficulty for clinicians unskilled in pulmonary embolism diagnosis in determining whether a patient with a positive D-dimer test needs to undergo computed tomographic pulmonary angiography.

Objectives

We sought to develop a new clinical decision-making rule based on a positive D-dimer result to predict the probability of pulmonary embolism and to guide clinicians in making decisions regarding the need for computed tomographic pulmonary angiography.

Methods

We conducted a prospective, multicenter study in three hospitals in China. A total of 3014 inpatients with positive D-dimer results were included. In the derivation group, we built a multivariate logistic regression model and deduced a regression equation from which our score was derived. Finally, we validated the score in an independent cohort.

Results

Our score included nine variables (points): chest pain (1.4), chest tightness (2.3), shortness of breath (3.6), hemoptysis (3.4), heart rate ≥100 beats/min (3.6), blood gas analysis (2.9), electrocardiogram presenting a typical S1Q3T3 pattern (4.1), electrocardiogram findings (2.4), and ultrasonic cardiogram findings (3.7). The sensitivities and specificities were 100% and 86.94%, respectively, in the derivation group and 100% and 90.82%, respectively, in the validation group. Additionally, the observed and predicted proportions of patients who underwent computed tomographic pulmonary angiography were 16.82% and 10.76%, respectively, in the derivation group and 18.72% and 11.40%, respectively, in the validation group.

Conclusions

The new score can categorize inpatients with a positive D-dimer test as pulmonary embolism-likely or pulmonary embolism-unlikely, thus reducing unnecessary computed tomographic pulmonary angiography examinations.

Trends in Imaging for Suspected Pulmonary Embolism Across US Health Care Systems, 2004 to 2016

IMPORTANCE

In response to calls to reduce unnecessary diagnostic testing with computed tomographic pulmonary angiography (CTPA) for suspected pulmonary embolism (PE), there have been growing efforts to create and implement decision rules for PE testing. It is unclear if the use of advanced imaging tests for PE has diminished over time.

OBJECTIVE

To assess the use of advanced imaging tests, including chest computed tomography (CT) (ie, all chest CT except for CTPA), CTPA, and ventilation-perfusion (V/Q) scan, for PE from 2004 to 2016.

DESIGN, SETTING, AND PARTICIPANTS

Cohort study of adults by age group (18-64 years and ≥65 years) enrolled in 7 US integrated and mixed-model health care systems. Joinpoint regression analysis was used to identify years with statistically significant changes in imaging rates and to calculate average annual percentage change (growth) from 2004 to 2007, 2008 to 2011, and 2012 to 2016. Analyses were conducted between June 11, 2019, and March 18, 2020.

MAIN OUTCOMES AND MEASURES

Rates of chest CT, CTPA, and V/Q scan by year and age, as well as annual change in rates over time.

RESULTS

Overall, 3.6 to 4.8 million enrollees were included each year of the study, for a total of 52 343 517 person-years of follow-up data. Adults aged 18 to 64 years accounted for 42 223 712 person-years (80.7%) and those 65 years or older accounted for 10 119 805 person-years (19.3%). Female enrollees accounted for 27 712 571 person-years (52.9%). From 2004 and 2016, chest CT use increased by 66.3% (average annual growth, 4.4% per year), CTPA use increased by 450.0% (average annual growth, 16.3% per year), and V/Q scan use decreased by 47.1% (decreasing by 4.9% per year). The use of CTPA increased most rapidly from 2004 to 2006 (44.6% in those aged 18-64 years and 43.9% in those ≥65 years), with ongoing rapid growth from 2006 to 2010 (annual growth, 19.8% in those aged 18-64 years and 18.3% in those ≥65 years) and persistent but slower growth in the most recent years (annual growth, 4.3% in those aged 18-64 years and 3.0% in those ≥65 years from 2010 to 2016). The use of V/Q scanning decreased steadily since 2004.

CONCLUSIONS AND RELEVANCE

From 2004 to 2016, rates of chest CT and CTPA for suspected PE continued to increase among adults but at a slower pace in more contemporary years. Efforts to combat overuse have not been completely successful as reflected by ongoing growth, rather than decline, of chest CT use. Whether the observed imaging use was appropriate or was associated with improved patient outcomes is unknown.

Appropriateness of CT pulmonary angiograms according to current diagnostic guidelines based on risk stratification: A retrospective single-center study

BACKGROUND AND AIM

Assessment of appropriateness of CT pulmonary angiograms (CTPA) in patients with suspected pulmonary embolism (PE) is based on risk stratification algorithms such as simplified the Geneva Score (sGS) in combination with D-dimer blood tests. The aim of this study was to validate the diagnostic yield and appropriateness of CTPA examinations in accordance with 2014 European Society of Cardiology (ESC) guidelines.

MATERIALS AND METHODS

Data from 155 outpatients who underwent CTPA for clinical suspicion of PE were gathered from the radiology information system (RIS) and the clinical information system (CIS). We assessed the presence of sGS items and D-dimer blood test results in RIS from CTPA request forms and from clinical documentation in CIS.

RESULTS

Based on the RIS, there were 2.6% patients with high (sGS≥3) and 97.4% patients with low pre-test PE probability (sGS<3), and CTPA indication was formally comprehendible in 75.5% using sGS and D-dimer blood tests. Based on RIS and CIS data in combination, there were 41.3% patients with high and 58.7% patients with low pre-test PE probability, and CTPA indication was formally comprehendible in 88.4%. Using RIS and CIS in combination, PE probability was upgraded from low to high probability in 39.7% compared with RIS alone. In 12.9%, there was a lack of data in RIS for CTPA justification.

CONCLUSION

There is a high diagnostic yield when applying current diagnostic guidelines to our data. There was however a notable discrepancy between the data transferred to the CTPA request forms from the full clinical documentation, therefore not readily available for clinical decision making.

Diagnosis of pulmonary embolism in patients with acute exacerbations of chronic obstructive pulmonary disease: A cross-sectional study

INTRODUCTION

Pulmonary embolism (PE) remains a frequent complication in patients with chronic obstructive pulmonary disease (COPD). It is unclear that the extent to which the traditional risk stratifying scores for PE are accurate in this population.

METHODS

Cross-sectional study of adult patients with COPD and suspected PE included in an Institutional Registry of Thromboembolic Disease at a tertiary teaching hospital in the city of Buenos Aires, Argentina. We estimated the area under the receiver operating characteristic curves (AU-ROC), sensitivity and specificity of the Wells and Geneva scores using a positive computed tomography angiography as the gold standard for PE. We also estimated the sensitivity and specificity for the presence of isolated worsening of dyspnea at presentation, without other cardinal symptoms of acute exacerbation of COPD.

RESULTS

A total of 168 patients were included, of which 22% had confirmed PE. The AUC was 0.66 (95% CI 0.56-0.76) and 0.56 (95% CI 0.45-0.67) for the Wells and Geneva, respectively. Considering the most widely used cutoff points, the sensitivity and specificity were 24% and 90% for the Wells and 59% and 43% for the Geneva score, respectively. Isolated worsening of dyspnea on presentation had a sensitivity of 92% and specificity of 37%.

CONCLUSIONS

Both Wells and Geneva scores exhibit poor diagnostic accuracy for the diagnosis of PE in patients with COPD. The presence of isolated worsening of dyspnea on presentation could be an easy to identify criteria for the initial triage in this population. Further validation of our findings remains warranted.

Acute pulmonary embolism multimodality imaging prior to endovascular therapy

The manuscript discusses the application of CT pulmonary angiography, ventilation–perfusion scan, and magnetic resonance angiography to detect acute pulmonary embolism and to plan endovascular therapy. CT pulmonary angiography offers high accuracy, speed of acquisition, and widespread availability when applied to acute pulmonary embolism detection. This imaging modality also aids the planning of endovascular therapy by visualizing the number and distribution of emboli, determining ideal intra-procedural catheter position for treatment, and signs of right heart strain. Ventilation–perfusion scan and magnetic resonance angiography with and without contrast enhancement can also aid in the detection and pre-procedural planning of endovascular therapy in patients who are not candidates for CT pulmonary angiography.

Pulmonary embolism: update on management and controversies

Pulmonary embolism is a common and potentially fatal cardiovascular disorder that must be promptly diagnosed and treated. The diagnosis, risk assessment, and management of pulmonary embolism have evolved with a better understanding of efficient use of diagnostic and therapeutic options. The use of either clinical probability adjusted or age adjusted D-dimer interpretation has led to a reduction in diagnostic imaging to exclude pulmonary embolism. Direct oral anticoagulation therapies are safe, effective, and convenient treatments for most patients with acute venous thromboembolism, with a lower risk of bleeding than vitamin K antagonists. These oral therapeutic options have opened up opportunities for safe outpatient management of pulmonary embolism in selected patients. Recent clinical trials exploring the use of systemic thrombolysis in intermediate to high risk pulmonary embolism suggest that this therapy should be reserved for patients with evidence of hemodynamic compromise. The role of low dose systemic or catheter directed thrombolysis in other patient subgroups is uncertain. After a diagnosis of pulmonary embolism, all patients should be assessed for risk of recurrent venous thromboembolism to guide duration of anticoagulation. Patients with a venous thromboembolism associated with a strong, transient, provoking risk factor can safely discontinue anticoagulation after three months of treatment. Patients with an ongoing strong risk factor, such as cancer, or unprovoked events are at increased risk of recurrent events and should be considered for extended treatment. The use of a risk prediction score can help to identify patients with unprovoked venous thromboembolism who can benefit from extended duration therapy. Despite major advances in the management of pulmonary embolism, up to half of patients report chronic functional limitations. Such patients should be screened for chronic thromboembolic pulmonary hypertension, but only a small proportion will have this as the explanation of their symptoms. In the remaining patients, future studies are needed to understand the pathophysiology and explore interventions to improve quality of life.

Advances in the Diagnosis of Venous Thromboembolism: A Literature Review

The incidence of venous thromboembolism (VTE), including lower extremity deep vein thrombosis (DVT) and pulmonary embolism (PE) is increasing. The increase in suspicion for VTE has lowered the threshold for performing imaging studies to confirm diagnosis of VTE. However, only 20% of suspected cases have a confirmed diagnosis of VTE. Development of pulmonary embolism rule-out criteria (PERC) and update in pre-test probability have changed the paradigm of ruling-out patient with low index of suspicion. The D-dimer test in conjunction to the pre-test probability has been utilized in VTE diagnosis. The age appropriate D-dimer cutoff and inclusion of YEARS algorithm (signs of the DVT, hemoptysis and whether PE is the likely diagnosis) for the D-dimer cutoff have been recent updates in the evaluation of suspected PE. Multi-detector computed tomography pulmonary angiography (CTPA) and compression ultrasound (CUS) are the preferred imaging modality to diagnose PE and DVT respectively. The VTE diagnostic algorithm do differ in pregnant individuals. The prerequisite of avoiding excessive radiation has recruited planar ventilation-perfusion (V/Q) scan as preferred in pregnant patients to evaluate for PE. The modification of CUS protocol with addition of the Valsalva maneuver should be performed while evaluating DVT in pregnant individual.

Prevention of Pulmonary and Venous Thromboembolism Post Coronary Artery Bypass Graft Surgery - Literature Review

Objective

The current review evaluates recent literature on the different aspects of prophylaxis in postoperative pulmonary and venous thromboembolism and their main risk factors.

Methods

The literature survey was carried out based on the PubMed data using the keywords “coronary artery bypass graft” and “venous thromboembolism” as components of the search field title.

Results

Studies reported several risk factors for postoperative thromboembolism including advanced age, postoperative immobilization, type of thromboprophylaxis, obesity, and location of the surgery.

Conclusion

According to the studies, tailored prophylaxis could be easily adapted to decrease the intensity and duration of postoperative thromboembolism in a patient with several disorders and comorbidities, especially in cardiovascular disease.

Accuracy of the general practitioner's sense of alarm when confronted with dyspnoea and/or chest pain: a prospective observational study

OBJECTIVES

Dyspnoea and chest pain are symptoms shared with multiple pathologies ranging from the benign to life-threatening diseases. A Gut Feelings Questionnaire (GFQ) has been validated to measure the general practitioner's (GPs) sense of alarm or sense of reassurance. The aim of the study was to estimate the diagnostic test accuracy of GPs' sense of alarm when confronted with dyspnoea and chest pain.

DESIGN AND SETTINGS

Prospective observational study in general practice.

PARTICIPANTS

Patients aged between 18 and 80 years, consulting their GP for dyspnoea and/or chest pain, were considered for enrolment. These GPs had to complete the GFQ immediately after the consultation.

PRIMARY OUTCOME MEASURES

Life-threatening and non-life-threatening diseases have previously been defined according to the pathologies or symptoms in the International Classification of Primary Care (ICPC)-2 classification. The index test was the sense of alarm and the reference standard was the final diagnosis at 4 weeks.

RESULTS

25 GPs filled in 235 GFQ questionnaires. The positive likelihood ratio for the sense of alarm was 2.12 (95% CI 1.49 to 2.82), the negative likelihood ratio was 0.55 (95% CI 0.37 to 0.77).

CONCLUSIONS

Where the physician experienced a sense of alarm when a patient consulted him/her for dyspnoea and/or chest pain, the post-test odds that this patient had, in fact, a life-threatening disease was about twice as high as the pretest odds.

TRIAL REGISTRATION NUMBER

NCT02932982.

A comparative analysis of the diagnostic performances of four clinical probability models for acute pulmonary embolism in a sub-Saharan African population: a cross-sectional study

Background

The diagnosis of acute pulmonary embolism (PE) is one of the most challenging in emergency settings where prompt and accurate decisions need to be taken for life-saving purposes. Here, the assessment of the clinical probability of PE is a paramount step in its diagnosis. Although clinical probability models (CPM) for PE are routinely used in emergency departments (EDs) of low-resource settings, few studies have cited their diagnostic performances in sub-Saharan Africa (SSA). We aimed to comparatively assess the accuracy of four CPM in the diagnosis of acute PE in sub-Saharan Africans.

Methods

We carried out a cross-sectional study to compare the sensitivity, specificity, positive and negative predictive values and accuracy of four CPM namely; the Wells, simplified Wells, revised Geneva and the simplified revised Geneva (SRG) Scores to computed tomography pulmonary angiography (CTPA) in all adults patients with suspected PE admitted to the EDs of the Gynaeco-obstetric and Paediatric Hospital of Yaoundé and the Yaoundé Central Hospital in Cameroon between January 1, 2017 and April 30, 2018.

Results

In total, we enrolled 30 patients with clinical suspicion of acute PE. PE was confirmed on CTPA in 16 (53.3%) cases. Their mean age was 53.7 ± 15.5 years and 36.7% were males. All four scores had a diagnostic performance superior to 50% in all criteria assessed. The simplified Wells score had the highest sensitivity (62.5%) followed by the Wells score (56.3%). The SRG score had the highest specificity (71.4%). The score with highest PPV was the SRG score (66.7%) and that with the highest NPV was the Wells score (56.3%). Overall the models with the highest accuracies were the Wells and SRG scores (60% for each).

Conclusion

All CPM had a suboptimal diagnostic performance, perhaps highlighting the need of a more optimal CPM for acute PE in SSA. However, the Wells and the SRG scores appeared to be most accurate than the other two scores in the ED. Hence, both or either of them may be used in first intention to predict PE and guide which ED patients should undergo further investigations in an emergency SSA setting.

EANM guideline for ventilation/perfusion single-photon emission computed tomography (SPECT) for diagnosis of pulmonary embolism and beyond

These guidelines update the previous EANM 2009 guidelines on the diagnosis of pulmonary embolism (PE). Relevant new aspects are related to (a) quantification of PE and other ventilation/perfusion defects; (b) follow-up of patients with PE; (c) chronic PE; and (d) description of additional pulmonary physiological changes leading to diagnoses of left ventricular heart failure (HF), chronic obstructive pulmonary disease (COPD) and pneumonia. The diagnosis of PE should be reported when a mismatch of one segment or two subsegments is found. For ventilation, Technegas or krypton gas is preferred over diethylene triamine pentaacetic acid (DTPA) in patients with COPD. Tomographic imaging with V/PSPECT has higher sensitivity and specificity for PE compared with planar imaging. Absence of contraindications makes V/PSPECT an essential method for the diagnosis of PE. When V/PSPECT is combined with a low-dose CT, the specificity of the test can be further improved, especially in patients with other lung diseases. Pitfalls in V/PSPECT interpretation are discussed. In conclusion, V/PSPECT is strongly recommended as it accurately establishes the diagnosis of PE even in the presence of diseases like COPD, HF and pneumonia and has no contraindications.

American Society of Hematology 2018 guidelines for management of venous thromboembolism: diagnosis of venous thromboembolism

BACKGROUND

Modern diagnostic strategies for venous thromboembolism (VTE) incorporate pretest probability (PTP; prevalence) assessment. The ability of diagnostic tests to correctly identify or exclude VTE is influenced by VTE prevalence and test accuracy characteristics.

OBJECTIVE

These evidence-based guidelines are intended to support patients, clinicians, and health care professionals in VTE diagnosis. Diagnostic strategies were evaluated for pulmonary embolism (PE), deep vein thrombosis (DVT) of the lower and upper extremity, and recurrent VTE.

METHODS

The American Society of Hematology (ASH) formed a multidisciplinary panel including patient representatives. The McMaster University GRADE Centre completed systematic reviews up to 1 October 2017. The panel prioritized questions and outcomes and used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess evidence and make recommendations. Test accuracy estimates and VTE population prevalence were used to model expected outcomes in diagnostic pathways. Where modeling was not feasible, management and accuracy studies were used to formulate recommendations.

RESULTS

Ten recommendations are presented, by PTP for patients with suspected PE and lower extremity DVT, and for recurrent VTE and upper extremity DVT.

CONCLUSIONS

For patients at low (unlikely) VTE risk, using D-dimer as the initial test reduces the need for diagnostic imaging. For patients at high (likely) VTE risk, imaging is warranted. For PE diagnosis, ventilation-perfusion scanning and computed tomography pulmonary angiography are the most validated tests, whereas lower or upper extremity DVT diagnosis uses ultrasonography. Research is needed on new diagnostic modalities and to validate clinical decision rules for patients with suspected recurrent VTE.

Unenhanced multidetector computed tomography findings in acute central pulmonary embolism

Background

Computed tomography pulmonary angiography (CTPA) is the gold standard for the diagnosis of pulmonary embolism (PE). However, contrast is contraindicated in some patients. The purpose of this study was to determine the diagnostic accuracy of unenhanced multidetector CT (MDCT) for diagnosis of central PE using CTPA as the gold standard.

Methods

The records of patients with suspected PE seen between 2010 and 2013 were retrospectively reviewed. Inclusion criteria were an acute, central PE confirmed by CTPA and non-enhanced MDCT before contrast injection. Patients with a PE ruled out by CTPA served as a control group. MDCT findings studied were high-attenuation emboli in pulmonary artery (PA), main PA dilatation > 33.2 mm, and peripheral wedge-shaped consolidation. Receiver operating characteristic (ROC) analysis was used to determine the sensitivity and specificity of unenhanced MDCT to detect PE. Wells score of all patients were calculated using data extracted from medical records prior to imaging analysis.

Results

Thirty-two patients with a PE confirmed by CTPA and 32 with a PE ruled out by CTPA were included. Among the three main MDCT findings, high-attenuation emboli in the PA showed best diagnostic performance (Sensitivity 72.9%; Specificity 100%), followed by main PA dilatation > 33.2 mm (sensitivity 46.9%; specificity 90.6%), and peripheral wedge-shaped consolidation (sensitivity 43.8%; specificity 78.1%). Given any one or more positive findings on unenhanced MDCT, the sensitivity was 96.9% and specificity was 71.9% for a diagnosis of PE in patients. The area under the curve (AUC) of a composite measure of unenhanced MDCT findings (0.909) was significantly higher than that of the Wells score (0.688), indicating unenhanced MDCT was reliable for detecting PE than Wells score.

Conclusions

Unenhanced MDCT is an alternative for the diagnosis of acute central PE when CTPA is not available.

Accuracy of the Ottawa score in risk stratification of recurrent venous thromboembolism in patients with cancer-associated venous thromboembolism: a systematic review and meta-analysis

In patients with cancer-associated venous thromboembolism, knowledge of the estimated rate of recurrent events is important for clinical decision-making regarding anticoagulant therapy. The Ottawa score is a clinical prediction rule designed for this purpose, stratifying patients according to their risk of recurrent venous thromboembolism during the first six months of anticoagulation. We conducted a systematic review and meta-analysis of studies validating either the Ottawa score in its original or modified versions. Two investigators independently reviewed the relevant articles published from 1st June 2012 to 15th December 2018 and indexed in MEDLINE and EMBASE. Nine eligible studies were identified; these included a total of 14,963 patients. The original score classified 49.3% of the patients as high-risk, with a sensitivity of 0.7 [95% confidence interval (CI): 0.6-0.8], a 6-month pooled rate of recurrent venous thromboembolism of 18.6% (95%CI: 13.9-23.9). In the low-risk group, the recurrence rate was 7.4% (95%CI: 3.4-12.5). The modified score classified 19.8% of the patients as low-risk, with a sensitivity of 0.9 (95%CI: 0.4-1.0) and a 6-month pooled rate of recurrent venous thromboembolism of 2.2% (95%CI: 1.6-2.9). In the high-risk group, recurrence rate was 10.2% (95%CI: 6.4-14.6). Limitations of our analysis included type and dosing of anticoagulant therapy. We conclude that new therapeutic strategies are needed in patients at high risk for recurrent cancer-associated venous thromboembolism. Low-risk patients, as per the modified score, could be good candidates for oral anticoagulation. (This systematic review was registered with the International Prospective Registry of Systematic Reviews as: PROSPERO CRD42018099506).

Non-invasive Multimodality Cardiovascular Imaging of the Right Heart and Pulmonary Circulation in Pulmonary Hypertension

Pulmonary hypertension (PH) is defined as resting mean pulmonary arterial pressure (mPAP) ≥25 millimeters of mercury (mmHg) via right heart (RH) catheterization (RHC), where increased afterload in the pulmonary arterial vasculature leads to alterations in RH structure and function. Mortality rates have remained high despite therapy, however non-invasive imaging holds the potential to expedite diagnosis and lead to earlier initiation of treatment, with the hope of improving prognosis. While historically the right ventricle (RV) had been considered a passive chamber with minimal role in the overall function of the heart, in recent years in the evaluation of PH and RH failure the anatomical and functional assessment of the RV has received increased attention regarding its performance and its relationship to other structures in the RH-pulmonary circulation. Today, the RV is the key determinant of patient survival. This review provides an overview and summary of non-invasive imaging methods to assess RV structure, function, flow, and tissue characterization in the setting of imaging's contribution to the diagnostic, severity stratification, prognostic risk, response of treatment management, and disease surveillance implications of PH's impact on RH dysfunction and clinical RH failure.

Age-dependent diagnostic accuracy of clinical scoring systems and D-dimer levels in the diagnosis of pulmonary embolism with computed tomography pulmonary angiography (CTPA)

OBJECTIVE

The aim of this study was to compare the age-dependent diagnostic performance of clinical scores and D-dimer testing to identify patients with suspected pulmonary embolism (PE).

METHODS

Consecutive patients with suspected PE referred from the emergency department for computed tomography pulmonary angiography (CTPA) were retrospectively evaluated. Diagnostic scores (classic Wells score (WS), modified WS, simplified WS, revised Geneva score (GS), simplified GS, and YEARS score) were calculated from medical records. Results of D-dimer testing were retrieved from the laboratory database. CTPA was the diagnostic reference standard. Four age groups were analyzed (< 50, 50-64, 65-74, and ≥ 75 years). Statistical analysis used receiver operating characteristics as well as uni- and multivariate analyses with calculation of prediction models. The study was IRB approved.

RESULTS

One thousand consecutive patients were included. Areas under the curve (AUC) and accuracies were superior in patients < 50 years. For the classic WS, the AUC decreased by 11% with the optimal cutoff dropping 1.5 points in patients ≥ 75 years; for D-dimer levels, the optimal cutoff was 900 μg/L higher in both ≥ 65 years groups with a max. decrease of the AUC of 9%. In terms of accuracy, the YEARS score performed best across all groups. Classic WS and D-dimer level showed a significant interaction with patient age in prediction models.

CONCLUSION

D-dimer measurement and clinical scores perform best in patients < 50 years. The YEARS score performs best across all age groups and is therefore recommended.

KEY POINTS

• The probability of pulmonary embolism predicted by fibrin fibrinogen degradation products and clinical scores shows the highest accuracy in patients < 50 years. • The probability of pulmonary embolism predicted by the YEARS score shows the highest accuracy in each age group. • Classic Wells score and fibrin fibrinogen degradation products show a significant interaction with patient age in a logistic regression model.