Simplified diagnostic management of suspected pulmonary embolism (the YEARS study): a prospective, multicentre, cohort study

The Legend score synthesizes Wells, PERC, Geneva, D-dimer and predicts acute pulmonary embolism prior to imaging tests

INTRODUCTION

The prediction rules of acute pulmonary embolism(PE) before imaging tests recommended by the commonly used guidelines have low diagnostic efficiency if not combined with D-dimer, therefore it is necessary to seek for a prediction rule with higher diagnostic efficiency.

METHODS

We designed a new score named Legend by synthesizing the scores of Wells, PERC, and Geneva, as well as D-dimer with patients in the development group(n = 2112), and then validated it in patients of validation group(n = 388). Diagnostic efficiency was also compared between Legend score and Wells+D-dimer (DD), PERC+DD, Geneva+DD, and YEARS+DD(YEAR algorithm).

RESULTS

The Legend score comprised active cancer, D-dimer≥1000 ng/mL, DVT symptoms and/or signs, previous venous thromboembolism (VTE) history, and surgery, trauma, or immobilization in the past month. The sensitivity, specificity, Youden index, and area under the curve(AUC) were 0.985, 0.744, 0.729, and (0.861[0.796-0.925], P<0.001), respectively, for original Legend score, whereas were 0.982, 0.778, 0.760, and (0.871[0.823-0.920], P<0.001), respectively, for simplified Legend score. The Kappa coefficient and P value of McNemar test were 0.988 and 1.000, respectively, between the original and simplified Legend scores. In the validation group, the sensitivity, specificity, Youden index, and C-index were 0.971, 0.749, 0.720, and (0.838[0.781-0.896], P<0.001), respectively, for the original Legend score, whereas were 0.986, 0.715, 0.701, and (0.816[0.750-0.880], P = 0.001) respectively, for the simplified Legend score. The Kappa coefficient and P value of McNemar test between original Legend score and Wells+DD, PERC+DD, Geneva+DD, and YEARS+DD were (0.563, 0.001), (0.139, <0.001), (0.631, 0.006), and (0.732, 0.029), respectively. The Kappa coefficient and P value of McNemar test between simplified Legend score and aforementioned scores were (0.675, 0.009), (0.172, <0.001), (0.747, 0.001), and (0.883, 0.012), respectively.

DISCUSSION

In view of the fact the Legend score reserves the efficient predictors and eliminates the inefficient ones in Wells, PERC, and revised Geneva scores, and incorporates D-dimer into it, a more efficient, modified, and user-friendly one has replaced the original ones.

CONCLUSIONS

The Legend score yields excellent diagnostic efficiency with good safety in the pretest prediction of acute PE prior to imaging tests. It also avoids more unnecessary imaging tests than Wells+DD, PERC+DD, Geneva+DD, or YEARS+DD.

Comparative diagnostic accuracy of pre-test clinical probability scores for the risk stratification of patients with suspected pulmonary embolism: a systematic review and Bayesian network meta-analysis

BACKGROUND

The primary evaluation of pulmonary embolism (PE) is complicated by the presence of various pre-test clinical probability scores (pCPS) with different cut-offs, all equally recommended by guidelines. This lack of consensus has led to practice variability, unnecessary imaging, and worse patient outcomes. We aim to provide more definitive insights through a holistic comparison of available pCPS.

METHODS

PubMed, Embase and Web of Science, and Google Scholar were searched for studies evaluating pCPS in patients clinically suspected of PE until June 2023. Risk of bias was evaluated using QUADAS-2. Included pCPS were evaluated based on their diagnostic accuracy in: (1) Ruling-out PE (2) Utilization of imaging, and (3) Differentiating between patients needing d-dimer from imaging. Diagnostic test accuracy indices were synthesized using beta-binomial Bayesian methods.

RESULTS

Forty studies (37,027 patients) were included in the meta-analysis. Three-tier revised Geneva (RG) and three-tier Wells performed similarly in ruling-out PE (negative likelihood ratio (LR-) [95% credible interval (CI)]: 0·39[0·27-0·58] vs 0·34[0·25-0·45]). However, RG performed better in utilization of imaging (LR + : 6·65[3·75-10·56] vs 5·59[3·7-8·37], p < 0.001) and differentiating between patients needing d-dimer vs imaging (diagnostic odds ratio (DOR): 8·03[4·35-14·1] vs. 7·4[4·65-11·84], p < 0.001). The two-tier Wells score underperformed in all aspects (LR-: 0·56[0·45-0·68], LR + : 2·43[1·81-3·07], DOR: 4·41[2·81-6·43]). PERC demonstrated a reliable point estimate for ruling out PE, albeit with a wide CI (LR-: 0·36[0·17-0·78]).

CONCLUSIONS

RG outperforms other pCPS for primary evaluation of suspected PE. While the difference is not large, RG's independence from subjective items supports its recommendation over three-tier Wells. Two-tier Wells underperforms significantly compared to the rest of pCPS. PERC shows considerable promise for minimizing unnecessary D-dimer testing in crowded emergency departments; however, more evidence is needed before its definitive recommendation.

PROTOCOL REGISTRATION

PROSPERO (CRD42023464118).

Enhancing Pulmonary Embolism Risk Stratification: The National Early Warning Score and Its Integration into the European Society of Cardiology Classification

Pulmonary embolism (PE) requires accurate risk assessment. We investigated the prognostic performance of the National Early Warning Score (NEWS) in emergency department patients with PE.We included patients ≥ 18 years from our PE registry (2017 to 2021), excluding patients after cardiac arrest or intubation before admission. The primary outcome was a composite of 30-day all-cause mortality or the need for advanced therapy (i.e., systemic or catheter-directed thrombolysis). We used logistic regression and the Cox proportional hazards models to estimate associations. The Pulmonary Embolism Severity Index (PESI) and the European Society of Cardiology (ESC) classification served as covariates. The overall score performances were quantified using receiver operating characteristic analysis.We included 524 patients. Each increase in NEWS points increased the odds of the primary outcome by 69% (odds ratio: 1.69, 95% confidence interval [CI]: 1.51-1.89, p < 0.001) and 30-day mortality by 44% (hazard ratio: 1.44, 95% CI: 1.30-1.60, p < 0.001). Within the ESC intermediate-high and high-risk group, the 30-day mortality rate was higher in patients with a NEWS ≥ 7 compared with NEWS < 7 (24 vs. 1%, p < 0.001). With a NEWS ≥ 7, 30-day mortality was lower in patients who received advanced therapy (18 vs. 39%) but not significantly. The NEWS predicted the primary outcome better than the PESI (area under the curve: 0.853 vs. 0.752, p < 0.001).The NEWS was associated with 30-day mortality and the need for advanced therapy. Incorporating the NEWS into the ESC classification could help to assess patient outcomes early and thus support timely treatment decisions.

Controversies in the Management of Acute Pulmonary Embolism in the Emergency Department

BACKGROUND

Acute pulmonary embolism (PE) is frequently diagnosed in the Emergency Department (ED), and the management approach can be nuanced.

OBJECTIVE

In this narrative review, we synthesize the literature in selected areas of ongoing controversy regarding the diagnostic and management approaches for acute PE in the ED, and provide evidence-based recommendations to empower emergency physicians (EPs) to provide optimal care in these situations.

DISCUSSION

d-Dimer is used to clinically exclude the diagnosis of PE patients who are stratified as low risk. However by utilizing likelihood ratio and with certain scoring tools, patient historically considered moderate or high risk for PE may safely be able to have the diagnosis excluded with a negative d-dimer. Traditional risk stratification and management strategies can be cautiously applied to patients with concomitant Coronavirus-19 infection while awaiting more definitive studies. There is an increasing trend in the diagnosis of isolated subsegmental PE, and many patients receiving this diagnosis may be treated without anticoagulation provided that they have no evidence of associated deep vein thrombosis (DVT) and can be closely followed as an outpatient. There is a persistent hesitancy to discharge patients with newly diagnosed acute PE, and existing well-supported risk stratification tools and clinical decision frameworks can support the EP's decision to safely discharge low-risk patients.

CONCLUSION

tThis review of the literature empowers emergency clinicians to manage challenging PE cases in the ED.

Basics of diagnosis and treatment of venous thromboembolism

Venous thromboembolism (VTE), comprising deep vein thrombosis and pulmonary embolism (PE), is common and associated with significant morbidity and mortality. The symptoms and signs of VTE are nonspecific. Well-established integrated diagnostic strategies combining clinical probability scores and D-dimer are used to identify patients with a low probability of VTE, where the diagnosis can be safely excluded without imaging. In patients with confirmed VTE, anticoagulation is the mainstay of treatment. However, patients with high-risk features at presentation may benefit from advanced reperfusion therapies such as thrombolysis and/or interventional approaches to reduce early mortality and/or long-term morbidity. The advent of direct oral anticoagulants has greatly simplified the treatment of VTE for most patients, with a persisting role for low molecular weight heparin and vitamin K antagonists in select patient groups. Following an initial 3 to 6 months of anticoagulation, those with major transient provoking factors can safely discontinue anticoagulation. Balancing the risk of recurrent VTE and bleeding risk is central to decisions regarding long-term anticoagulation, and patients should be included in shared decision-making. Assessment and recognition of common long-term complications such as postthrombotic syndrome and post-PE syndrome are also essential, given they are associated with significant adverse impact on long-term quality of life, with a significant risk of mortality associated with the less frequent complication of chronic thromboembolic pulmonary hypertension. This review provides a basic overview and framework for the diagnostic approach to deep vein thrombosis and PE, risk stratification of confirmed diagnoses, and management.

Factors Predicting CT Pulmonary Angiography Results in the Emergency Department

Background: Pulmonary embolism (PE) remains a major concern in emergency patients presenting with respiratory symptoms, with an increase in the demand for CT pulmonary angiography (CTPA) and low yields of this ever more sensitive test. We wanted to investigate factors associated with pulmonary embolism on CTPA, aiming to reduce unnecessary requests. Methods: In a single-center, retrospective study, we analyzed all CTPA reports for emergency patients during the year 2023. Various patients' variables were evaluated for associations with the presence/absence of PE, including the presence or absence of pulmonary pathology identified prior to the CTPA order. Results: A total of 1555 CTPA reports were analyzed, of which 278 (17.9%) were positive for PE. The highest ORs (40.9) for PE were found for patients diagnosed with DVT prior to CTPA. The lowest odds ratios of having PE were found for patients with acute congestive heart failure (OR = 0.141), especially in the absence of cancer (OR = 0.089) and for patients with hypercapnia in COPD exacerbation (OR = 0.062). Tachycardia and hypoxemia were the physiological variables positively associated with PE, while hypercapnia was negatively associated with PE. For patients with heart failure, COPD exacerbation, and pneumonia, higher D-dimer cut-off values (3.87 mg/L, 1.25 mg/L, and 1.34 mg/L, respectively) were found to retain 100% sensitivity for PE. Conclusions: Stricter criteria for CTPA orders in the presence of other pulmonary pathologies may reduce unnecessary scanning. Higher D-dimer cut-off values in such cases may lead to higher specificity without sacrificing sensitivity.

A review of venous thromboembolism for the hospitalist

Venous thromboembolism (VTE), consisting of both deep vein thrombosis (DVT) and pulmonary embolism (PE), is an extremely common condition both in the United States and worldwide. Not only is the diagnosis associated with significant morbidity and mortality for patients but it also imposes a deleterious financial burden on the US healthcare system. Diagnosis may be challenging due to variability in clinical presentation and requires a sequential workup including assessment of clinical pretest probability for VTE, D-dimer testing, and imaging. Following diagnosis, proper risk stratification is necessary to determine the appropriate treatment as well as the need for inpatient care. Elucidation of underlying major or minor risk factors at the time of diagnosis is essential as the presence of which may influence the duration of therapy. First-line treatment for most patients is anticoagulation with a direct oral anticoagulant (DOAC) for a minimum of 3-6 months. In multiple clinical trials, DOACs have proven to be non-inferior to vitamin K antagonists for the treatment of VTE with a lower risk of bleeding. Special consideration should be taken in the choice of agent and duration of treatment for patients who have underlying thrombophilias or malignancy and who are pregnant.

Diagnosis and treatment of pulmonary embolism. Recommendations of the Thromboembolic Disease Group of the Spanish Society of Internal Medicine 2024

Pulmonary embolism (PE) is a disease with a rising incidence rate. This article presents the recommendations for the diagnosis and treatment of PE of the Thromboembolic Disease Group of the Spanish Society of Internal Medicine (SEMI). The main objective is to facilitate decision making to improve the diagnostic and therapeutic approach based on published evidence. The final justification of the document is to improve the comprehensive care of the patient with PE.

The Potential Effect on the Number of Computerized Tomography Pulmonary Angiography if a Clinical Probability-Adjusted D-dimer Is Added to an Age-Adjusted D-dimer

Introduction Computerized tomography pulmonary angiography (CTPA) is the gold standard test for diagnosing pulmonary embolism (PE); however, owing to its high cost, contrast dye toxicity, and radiation exposure, it is necessary to ensure that CTPA is not performed unnecessarily. European Society of Cardiology (ESC) guidelines recommend the use of pretest clinical assessment tools and D-dimer levels to stratify patients according to risk, thereby determining the need for CTPA. However, such a broad classification incorporates a large population, where cases of CTPA could have been avoided. In this retrospective observational study, we established a new cohort within the moderate risk group, using a D-dimer threshold of 1000 ng/dL, and thereby aimed to identify its impact in identifying the number of cases of CTPA and to identify the number of cases of PE missed. Materials and methods This observational retrospective study was conducted over 24 months in the emergency medicine department of a tertiary care hospital in south India. Our study comprised of evaluation of electronic medical records of patients based on the inclusion and exclusion criteria. An overall 182 samples (n=182) were recruited, past medical records were evaluated, and classified patients were classified according to the new stratification criteria based on the Wells score, pulmonary embolism rule-out criteria (PERC), and D-dimer levels. The study outcomes of the number of CTPA cases avoided and PE cases missed out were analyzed. Results Assuming all samples (n=182) fell into the low moderate risk (LMR) category (Wells score<2 and PERC positive, or Wells score 2-4), 95 cases (n=95, 95/182) had D-dimer<1000 ng/dL, among which PE was absent in 93 patients (n=93, 97.89%) and present in 2 patients (n=2, 2.10%). The remaining 87 (n=87, 87/182) had D-dimer≥1000 ng/dL where all cases had PE (n=87, 100%). Assuming the samples (n=182) fell into the high moderate risk (HMR) category (Wells score 4.5-6), 21 cases (n=21, 21/182) had D-dimer< age-adjusted D-dimer (AADD) among which, PE was absent in 20 patients (n=20, 95.23 %) and present in 1 patient (n=1, 4.76%). The remaining 161 (n=161, 161/182) had D-dimer≥AADD, whereas all cases had PE (n=161, 100%). The false negative rates were 2.1% in LMR and 4.8% in HMR, while the reduction in CTPA procedures amounted to 95 scans in LMR and 21 scans in HMR. Conclusions  We identified that establishing a higher threshold of D-dimer (1000 ng/dL) was effective in determining the need for CTPA and potentially reducing the number of CTPAs performed in suspected cases of PE.

YEARS clinical decision rule for diagnosing pulmonary embolism: a prospective diagnostic cohort follow-up study in primary care

OBJECTIVES

The Wells rule is often used in primary care to rule out pulmonary embolism (PE), but its efficiency is low as many referred patients do not have PE. In this study, we evaluated in primary care an alternative and potentially more efficient diagnostic strategy-the YEARS algorithm; a simplified three-item version of the Wells rule combined with a pretest probability adjusted D-dimer interpretation.

DESIGN

In this comprehensive prospective diagnostic validation study, primary care patients suspected of PE were enrolled by their general practitioner. All three YEARS items were collected in addition to D-dimer results, and patients were followed for 3 months to establish the final diagnosis.

SETTING

Primary care in the Netherlands.

PARTICIPANTS

753 patients with suspected acute PE were included. Five patients (0.7%) were lost to follow-up.

MAIN OUTCOME MEASURES

Failure rate (number of PE cases among patients classified by the algorithm as 'PE ruled-out') and efficiency (fraction of patients classified as 'PE probable/further imaging needed').

RESULTS

Prevalence of PE was 5.5% (41/748 patients). In total, 603 patients were classified as 'PE ruled-out' by the YEARS algorithm (532 with zero YEARS items and a D-dimer<1000 ng/mL and 71 with≥1 positive YEARS item and a D-dimer<500 ng/mL), resulting in an efficiency of 80.6% (603/748 patients, 95% CI 77.6% to 83.4%). Of these patients, three patients had a diagnosis of non-fatal PE during 3 months follow-up, all three with zero YEARS items and D-dimer between 500 and 1000 ng/mL, resulting in an overall diagnostic failure rate of 0.50% (3/603 patients, 95% CI 0.13% to 1.57%). In the patients categorised as 'imaging needed' (n=145), a total of 38 (26.2%) were indeed diagnosed with PE.

CONCLUSIONS

Our study suggests that acute PE can be safely ruled out in 80% of patients by the YEARS algorithm in a primary care setting, while only 20% of patients required referral to hospital care for imaging tests. In those classified as 'imaging needed', PE was present in about one in every four patients, demonstrating a high detection proportion.

Implementation of an electronic ordering algorithm based on the YEARS criteria to optimize pulmonary embolism diagnostic workup in the emergency department

OBJECTIVE

The YEARS criteria combine D-dimer testing and clinical features (hemoptysis, signs of deep vein thrombosis, and pulmonary embolism as the most likely diagnosis) to risk stratify patients with symptoms of pulmonary embolism who may undergo CT pulmonary angiography in the emergency department (ED). Electronic clinical decision support can optimize CT pulmonary angiography utilization in EDs, yet its effectiveness with the YEARS criteria remains unstudied. Our goal is to increase the percentage of CT pulmonary angiograms performed with a D-dimer by 10% within six months of integrating the YEARS criteria into our electronic ordering system.

METHODS

Single centre quality improvement initiative for all ED patients > 18 years investigated for pulmonary embolism with a D-dimer and/or CT pulmonary angiogram between Jan 2022 - Jan 2023. An electronic clinical decision support algorithm was created based on the YEARS criteria and a plan-do-study-act cycle was completed. Using an SPC chart, the percentage of CT pulmonary angiograms ordered with a D-dimer was identified. Process measures included the rate of CT pulmonary angiograms ordered, the rate of imaging ordered in accordance with the YEARS criteria, and diagnostic yield of imaging based on YEARS status. Balancing measures included pulmonary embolism identified on CT pulmonary angiogram with a D-dimer < 500 ug/L FEU or within 30 days of index visit after being ruled out with the YEARS criteria.

RESULTS

Over 12 months, 2639 patients were investigated for pulmonary embolism and 906 underwent CT pulmonary angiogram. The percentage of CT pulmonary angiograms ordered with a screening D-dimer increased by 14.5% (63.8%, CI 59.5-68.1% vs 78.4%, CI 74.4-82.3%) without increasing the rate of imaging ordered (34.9%, CI 32.4-37.4% vs 33.7%, CI 31.1-36.3%). The YEARS criteria were properly applied in 60% (255/425) of patients who underwent CT pulmonary angiogram. The diagnostic yield of CT pulmonary angiogram was higher if patients were YEARS positive (13.2%, CI 9.0-17.4) compared to YEARS negative (0%, CI 0-28.3) or if not applied (8.1%, CI 3.9-12.4). There were two missed pulmonary embolisms at baseline and none post-intervention.

CONCLUSIONS

Implementation of the YEARS criteria using electronic ordering assistance increased the percentage of CT pulmonary angiograms ordered with a D-dimer without increasing imaging use in the ED.

Comparison of the diagnostic performance of non-contrast MR angiography and planar V/Q scintigraphy for pulmonary embolism: a systematic review and meta-analysis

OBJECTIVES

To conduct a meta-analysis of the diagnostic performance of non-contrast magnetic resonance pulmonary angiography (NC-MRPA) and ventilation-perfusion (V/Q) scintigraphy for the detection of acute pulmonary embolism (PE).

MATERIALS AND METHODS

Systematic searches of electronic databases were conducted from 2000 to 2024. Primary outcomes were per-patient sensitivity and specificity of NC-MRPA and V/Q scintigraphy. The pooled sensitivities, specificities, and 95% confidence intervals (95% CI) were calculated using a random-effect analysis. Summary receiver-operating characteristic (SROC) curves and the area under the curve (AUC) were obtained.

RESULTS

A total of 3709 studies (1941 NC-MRPA studies) were identified through systematic searches, with eight published MRI and nine published V/Q investigations meeting inclusion criteria. The results showed that NC-MRPA had a pooled sensitivity of 0.88 (95% CI: 0.83-0.91) and specificity of 0.97 (95% CI: 0.93-0.98), yielding an AUC of 0.92 (95% CI: 0.85-0.96). V/Q scanning had a pooled sensitivity of 0.81 (95% CI: 0.76-0.85) and specificity of 0.84 (95% CI: 0.74-0.91), yielding an AUC of 0.87 (95% CI: 0.75-0.91). The pooled proportion of non-diagnostic tests for V/Q scans (34.7%, 95% CI: 30.8-38.7) was greater than that of NC-MRPA studies (3.31%, 95% CI: 1.65-4.97).

CONCLUSION

This meta-analysis suggests that NC-MRPA is more specific than V/Q scintigraphy for the detection of PE, with comparable accuracy and sensitivity. NC-MRPA yielded fewer non-diagnostic scans than V/Q scintigraphy and is a feasible alternative imaging modality for diagnosing PE in patients for whom intravenous contrast administration poses a substantive risk.

KEY POINTS

Question V/Q lung scintigraphy has been used as a reserve, alternative modality for patients who cannot undergo CT pulmonary angiography. Findings Non-contrast MR angiography (MRA) is a feasible alternative for diagnosing PE in patients for whom intravenous iodinated contrast administration poses a substantial risk. Clinical relevance Non-contrast MRA provides similar sensitivity and superior specificity to V/Q scintigraphy for diagnosing PE, without ionizing radiation exposure.

Type of D-dimer assay determines the diagnostic yield of computed tomography in patients suspected for pulmonary embolism

Background

Pulmonary embolism (PE) is a life-threatening condition with high morbidity and mortality. The diagnosis of PE is challenging due to nonspecific symptoms, making reliable diagnostic tools essential. This study addresses the clinical impact of interassay variability in D-dimer measurements on the utilization and diagnostic yield of computed tomography pulmonary angiography (CTPA).

Objectives

To investigate the effect of different D-dimer assays on the decision to perform CTPA and the subsequent diagnostic yield in patients with suspected PE.

Methods

This retrospective, multicenter cohort study analyzed data from 3 teaching hospitals in the southwest region of the Netherlands, covering the years 2018, 2019, 2022, and 2023. The study included data from 40,096 clinically requested D-dimer results and 11,372 CTPA records of patients with suspected PE. The D-dimer assays used were the Roche Tina-quant and Siemens INNOVANCE.

Results

The study found significant differences in CTPA utilization and diagnostic yield based on the D-dimer assay used. In 2018 to 2019, hospitals using the Roche Tina-quant assay ordered 21% fewer CTPA scans and had a 9% higher positivity rate compared with those using the Siemens INNOVANCE assay.

Conclusion

The findings highlight the necessity for assay-specific cutoff values or, ideally, the standardization of the D-dimer assay to optimize the accuracy and efficiency of PE diagnosis. This study demonstrates that the choice of D-dimer assay significantly influences the clinical management of suspected PE, affecting both the number of CTPA scans performed and the positivity rate of these scans. Implementing assay-specific cutoff values or standardization of the D-dimer assay could reduce unnecessary CTPA scans, minimize patient exposure to radiation, and lower healthcare costs. These results advocate enhanced collaboration between clinicians and laboratory specialists to accurately interpret D-dimer results within the context of the specific assay used. Future research should validate these findings in prospective studies and explore standardized protocols that account for interassay variability.

Heart Failure Masked as Pulmonary Embolism in Non-adherent Patient With Atrial Fibrillation: Case Report and Analytical Review of the Literature

BACKGROUND/AIM

Atrial fibrillation (AF) and heart failure (HF) commonly co-occur, significantly increasing morbidity and mortality. Poorly controlled AF can contribute to complications like HF and is associated with conditions, such as stroke and pulmonary embolism (PE). This report involves a man with AF who had persistent respiratory symptoms and left-sided chest pain, initially suspected to be PE, but eventually diagnosed as HF.

CASE REPORT

A 43-year-old male experienced increasing breathlessness, cough, and fatigue. Initially suspected to have a respiratory infection, his persistent symptoms raised concern for PE. The patient had a history of AF, unsuccessful cardioversion, and long-term non-adherence to beta blockers. Initial assessment revealed persistent respiratory symptoms and elevated levels of C-reactive protein, D-dimer, N-terminal pro-B-type natriuretic peptide, and Troponin T. Chest X-ray showed pulmonary congestion, and echocardiogram confirmed a severely impaired ejection fraction (EF <20%). While the differential diagnosis included community-acquired pneumonia, PE, and HF, the final diagnosis was worsening AF and HF with reduced EF, not PE.

CONCLUSION

PE symptoms can overlap with HF, making careful differential diagnosis essential, particularly in AF patients with elevated D-dimer levels, where false positives necessitate caution. This case underscores the importance of thorough differential diagnosis and clinical judgment before ordering tests to avoid misdiagnosis. Long-term non-adherence to beta blockers exacerbated the patient's symptoms, emphasising the critical role of consistent medication use in managing AF and preventing complications like HF. This case report also highlights the importance of thorough investigations, guideline-based treatments and multidisciplinary care in complex AF-HF cases.

Development of a predictive nomogram for early identification of pulmonary embolism in hospitalized patients: a retrospective cohort study

BACKGROUND

Hospitalized patients often present with complex clinical conditions, but there is a lack of effective tools to assess their risk of pulmonary embolism (PE). Therefore, our study aimed to develop a nomogram model for better predicting PE in hospitalized populations.

METHODS

Data from hospitalized patients (aged ≥ 15 years) who underwent computed tomography pulmonary angiography (CTPA) to confirm PE and non-PE were collected from December 2013 to April 2023. Univariate and multivariate stepwise logistic regression analyses were conducted to identify independent predictors of PE, followed by the construction of a predictive nomogram and internal validation. The efficiency and clinical utility of the nomogram model were assessed using receiver operating characteristic (ROC) curve, decision curve analysis (DCA), and clinical impact curve (CIC).

RESULTS

The study included 313 PE and 339 non-PE hospitalized patients. Male gender, dyspnea or shortness of breath, interstitial lung disease, lower limb deep vein thrombosis, elevated fibrin degradation product (FDP), pulmonary arterial hypertension, and tricuspid regurgitation were identified as independent risk factors. The AUC of the predictive nomogram model was 0.956 (95% CI: 0.939-0.974), demonstrating superior performance compared with the simplified Wells score of 0.698 (95% CI: 0.654-0.741) and the modified Geneva score of 0.758 (95% CI: 0.717-0.799).

CONCLUSION

Our study demonstrated that challenges remain in the accuracy of the Wells score and revised Geneva score in assessing PE in hospitalized patients. Fortunately, the nomogram we developed has shown a favorable ability to discriminate PE cases, providing high reference value for clinical practice. However, given that this was a single-center study, we plan to expand efforts to collect data from additional centers to further validate our model.

A Comparative Analysis of the Impact of Severe Acute Respiratory Syndrome Coronavirus 2 Infection on the Performance of Clinical Decision-Making Algorithms for Pulmonary Embolism

Background/Objectives: This study aimed to compare the diagnostic accuracy of the Wells and Geneva scores using a 500 ng/mL D-dimer cutoff, as well as the age-adjusted D-dimer (AADD), YEARS, and pulmonary embolism graduated D-dimer (PEGeD) algorithms, in patients with and without COVID-19. Various D-dimer cutoffs were also evaluated. Methods: This retrospective study included emergency department patients who underwent computed tomography pulmonary angiography (CTPA) for suspected pulmonary embolism (PE). The diagnostic performances of clinical prediction algorithms were compared between COVID-19-positive and -negative groups. Results: We analyzed data from 1423 patients; the PE and COVID-19 positivity rates were 7.3% and 69.9%, respectively. In COVID-19-positive patients, the Wells score with a 500 ng/mL D-dimer cutoff demonstrated 97.22% sensitivity (95% CI: 80.53-100.00) and 4.99% specificity (95% CI: 3.58-6.39). Using AADD raised the specificity to 7.81% (95% CI: 6.08-9.54) while maintaining 97.22% sensitivity (95% CI: 93.43-100.00); similar findings were observed with the Geneva score. The YEARS algorithm had 86.11% sensitivity (95% CI: 78.12-94.10) and 32.75% specificity (95% CI: 29.73-35.78), whereas the PEGeD algorithm showed 86.11% sensitivity (95% CI: 78.12-94.10) and 34.06% specificity (95% CI: 31.00-37.12). Both algorithms demonstrated slightly improved specificity and accuracy in COVID-19-positive patients. Conclusions: The YEARS and PEGeD algorithms showed slight improvements in specificity and accuracy among COVID-19-positive patients. The Wells and Geneva scores maintained higher sensitivity but lower specificity across groups. Adjusting the D-dimer cutoffs increased the specificity but increased the risk of missed diagnoses. Overall, COVID-19 had a minimal impact on PE diagnostic algorithm performances.

Diagnostic Test Accuracy of the YEARS Algorithm for Pulmonary Embolism: A systematic review and meta-analysis

This systematic review and meta-analysis aimed to assess the diagnostic accuracy of the YEARS algorithm in excluding pulmonary embolism, as well as to compare the utilisation of advanced imaging modalities between the YEARS approach and standard clinical practice. Eligible studies were identified from multiple databases spanning July 2017 to September 2022, following the Joanna Briggs Institute methodology for diagnostic accuracy reviews. A total of 10 studies, involving approximately 14,000 participants, were included in the analysis. The YEARS algorithm demonstrated a sensitivity of 96% (95% confidence interval [CI]: 93-98%) and a specificity of 50% (95% CI: 33-67%). Additonally, the risk ratio for advanced imaging utilisation was 0.78 (95% CI: 67-90), indicating a significant reduction in imaging use. These findings suggest that the YEARS is an effective and safe strategy for managing patients with suspected pulmonary embolism.

Implementation, Clinical Benefit and Safety of a D-Dimer-Focused Pulmonary Embolism Testing Pathway in the Emergency Department

STUDY OBJECTIVE

Computed tomography pulmonary angiogram (CTPA) is overused during pulmonary embolism (PE) testing in the emergency department (ED), whereas prediction rules and D-dimer are underused. We report the adherence, clinical benefit, and safety of a D-dimer-only strategy to guide need for PE imaging in the ED.

METHODS

This was a prospective multicenter implementation study in 2 EDs with historical and external controls. Patients with suspected PE underwent D-dimer testing and imaging (CTPA or ventilation-perfusion scan) when D-dimer levels were 500 ng/mL or more. PE was ruled out if D-dimer was less than 500 ng/mL or with negative imaging. The primary implementation outcome was the proportion of patients tested for PE in adherence with the pathway. The primary clinical benefit outcome was the proportion of patients tested for PE who received pulmonary imaging. The primary safety outcome was diagnosis of PE in the 30 days following negative PE testing postimplementation.

RESULTS

Between January 2018 and June 2021, 16,155 patients were tested for PE, including 33.4% postimplementation, 30.7% preimplementation, and 35.9% in an external control site. Adherence with the D-dimer-only pathway was 97.6% (adjusted odds ratio (aOR) post- versus preimplementation 5.26 (95% confidence interval 1.70 to 16.26). There was no effect on the proportion undergoing PE imaging. Imaging yield increased aOR 4.89 (1.17 to 20.53). Two cases of PE (0.04%; 0.01% to 0.16%) were diagnosed within 30 days.

CONCLUSION

In this Canadian ED study, the uptake of a D-dimer-only PE testing strategy was high. Implementation was associated with higher imaging yield and a D-dimer level of less than 500 ng/mL safely excluded PE.

Diagnosis of acute aortic syndromes with ultrasound and d-dimer: the PROFUNDUS study

BACKGROUND

In patients complaining common symptoms such as chest/abdominal/back pain or syncope, acute aortic syndromes (AAS) are rare underlying causes. AAS diagnosis requires urgent advanced aortic imaging (AAI), mostly computed tomography angiography. However, patient selection for AAI poses conflicting risks of misdiagnosis and overtesting.

OBJECTIVES

We assessed the safety and efficiency of a diagnostic protocol integrating clinical data with point-of-care ultrasound (POCUS) and d-dimer (single/age-adjusted cutoff), to select patients for AAI.

METHODS

This prospective study involved 12 Emergency Departments from 5 countries. POCUS findings were integrated with a guideline-compliant clinical score, to define the integrated pre-test probability (iPTP) of AAS. If iPTP was high, urgent AAI was requested. If iPTP was low and d-dimer was negative, AAS was ruled out. Patients were followed for 30 days, to adjudicate outcomes.

RESULTS

Within 1979 enrolled patients, 176 (9 %) had an AAS. POCUS led to net reclassification improvement of 20 % (24 %/-4 % for events/non-events, P < 0.001) over clinical score alone. Median time to AAS diagnosis was 60 min if POCUS was positive vs 118 if negative (P = 0.042). Within 941 patients satisfying rule-out criteria, the 30-day incidence of AAS was 0 % (95 % CI, 0-0.41 %); without POCUS, 2 AAS were potentially missed. Protocol rule-out efficiency was 48 % (95 % CI, 46-50 %) and AAI was averted in 41 % of patients. Using age-adjusted d-dimer, rule-out efficiency was 54 % (difference 6 %, 95 % CI, 4-9 %, vs standard cutoff).

CONCLUSIONS

The integrated algorithm allowed rapid triage of high-probability patients, while providing safe and efficient rule-out of AAS. Age-adjusted d-dimer maximized efficiency.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov, NCT04430400.

[Pulmonary Embolism]

Pulmonary embolism (PE), the most severe form of presentation of venous thromboembolic disease (VTE), currently represents a foremost healthcare issue due to its high impact in terms of morbidity, mortality, costs, and resource consumption. Early mortality associated with PE is primarily due to hemodynamic instability, exacerbation of pre-existing conditions, or major complications of antithrombotic therapies. Beyond the risk of death, there are relevant complications related to PE, such as bleedings, VTE recurrences, and persistence of residual respiratory symptoms; the latter complication related to PE is mainly characterized by two entities, chronic thromboembolic pulmonary hypertension and chronic thromboembolic disease. Significant scientific advances made in recent years have allowed for the improvement of both diagnostic and therapeutic management of the disease, as outlined in this document through a series of relevant issues about PE that are answered with the most up-to-date scientific evidence.

Could the YEARS algorithm be applied to evaluate suspected pulmonary embolism in hospitalized women after cesarean section?

OBJECTIVE

To evaluate the effectiveness of the YEARS algorithm for excluding pulmonary embolism (PE) in hospitalized women after cesarean section.

METHODS

This retrospective study included postpartum women who gave birth by cesarean section and received computed tomography pulmonary angiography (CTPA) because of suspected PE in the obstetric department between 2015 and 2021. We used the YEARS algorithm in these women retrospectively and assessed its performance to evaluate whether the algorithm could be reliably applied in such cases.

RESULTS

In all, 225 women were included in the study, of whom 29 (12.9%) women were positive for PE according to the results of CTPA. Upon retrospective application of the YEARS algorithm, 188 (83.6%) women had no YEARS items, while 37 (16.4%) women had YEARS items. Combining the results with D-dimer levels revealed that only 12 (5.3%) women did not need to undergo CTPA, and none showed PE.

CONCLUSION

The YEARS algorithm could be applied to exclude PE in hospitalized women in the early post-cesarean period. However, the specificity of the YEARS algorithm was very low, and the D-dimer cut-off for ruling out PE in women after early cesarean section should be further studied and optimized.

Comparison of the accuracy of four diagnostic prediction rules for pulmonary embolism in patients admitted to the emergency department

INTRODUCTION AND OBJECTIVES

Ruling out pulmonary embolism (PE) through a combination of clinical assessment and D-dimer level can potentially avoid excessive use of computed tomography pulmonary angiography (CTPA). We aimed to compare the diagnostic accuracy of the standard approach based on the Wells and Geneva scores combined with a standard D-dimer cut-off (500 ng/ml), with three alternative strategies (age-adjusted and the YEARS and PEGeD algorithms) in patients admitted to the emergency department (ED) with suspected PE.

METHODS

Consecutive outpatients admitted to the ED who underwent CTPA due to suspected PE were retrospectively assessed. Sensitivity, specificity, positive and negative predictive values, likelihood ratios and diagnostic odds ratios were calculated and compared between the different diagnostic prediction rules.

RESULTS

We included 1402 patients (mean age 69±18 years, 54% female), and PE was confirmed in 25%. Compared to the standard approach (p<0.001), an age-adjusted strategy increased specificity with a non-significant decrease in sensitivity only in patients older than 70 years. Compared to the standard and age-adjusted approaches, the YEARS and PEGeD algorithms had the highest specificity across all ages, but were associated with a significant decrease in sensitivity (p<0.001), particularly in patients aged under 60 years (sensitivity of 81% in patients aged between 51 and 60 years).

CONCLUSION

Compared to the standard approach, all algorithms were associated with increased specificity. The age-adjusted strategy was the only one not associated with a significant decrease in sensitivity compared to the standard approach, enabling CTPA requests to be reduced safely.

Diagnosis of pulmonary embolism in patients with haemoptysis: the POPEIHE study

Aim

To determine the prevalence and characteristics of pulmonary embolism (PE) in patients presenting with haemoptysis. Additionally, we assessed the efficiency and failure rates of different clinical diagnostic algorithms for PE in this patient population.

Methods

We enrolled consecutive adult patients who presented to nine Italian emergency departments with haemoptysis as the primary complaint. PE diagnosis was ruled out in patients with a low pre-test probability in combination with a negative age-adjusted D-dimer (referred to as the "age-adjusted" D-dimer strategy), a negative computed tomography pulmonary angiography or when a clear alternative source of bleeding was identified, along with negative findings for venous thromboembolism during a 30-day follow-up.

Results

A total of 546 patients were included in the study. The prevalence of PE, including the 30-day follow-up, was 4.2% (95% CI 2.7-6.3%). The majority of these cases (78%) exhibited distal (segmental or subsegmental) emboli and there were no PE-related fatalities. The "age-adjusted" D-dimer strategy initially excluded PE in 24% of patients (95% CI 21-28%), with a failure rate of 0.8% (95% CI 0.0-4.1%). Retrospectively applied, the "clinical probability-adjusted" D-dimer strategies, specifically the YEARS and Pulmonary Embolism Graduated d-Dimer (PEGeD) algorithms, excluded PE in a significantly higher proportion (30% and 32%, respectively) compared with the "age-adjusted" D-dimer strategy (p<0.05 for both), with similar failure rates.

Conclusions

PE is infrequent among patients presenting with haemoptysis, showing segmental or subsegmental emboli distribution. The "clinical probability-adjusted" D-dimer strategies seem to have significantly higher efficiency compared with the "age-adjusted" strategy.

Diagnostic management of acute pulmonary embolism

Straightforward, accurate diagnostic management in patients presenting with clinically suspected pulmonary embolism (PE) is essential, since starting anticoagulant treatment may give important adverse effects of bleeding, while false exclusion of the disease may lead to recurrent VTE, with associated morbidity and mortality. In the past three decades, considerable improvement in the diagnostic management of PE has been made. Computed tomography pulmonary angiography (CTPA) has largely replaced conventional pulmonary angiography and ventilation-perfusion lung scanning as the imaging methods of choice. Several diagnostic algorithms, all able to minimize the need for radiological imaging have been developed and validated. Lastly, within the diagnostic algorithms, varying d-dimer cut-off levels have successfully been introduced to further downsize the need for radiological imaging.

Renal function-adapted D-dimer cutoffs in combination with a clinical prediction rule to exclude pulmonary embolism in patients presenting to the emergency department

D-dimer levels significantly increase with declining renal function and hence, renal function-adjusted D-dimer cutoffs to rule out pulmonary embolism were suggested. Aim of this study was to "post hoc" validate previously defined renal function-adjusted D-dimer levels to safely rule out pulmonary embolism in patients presenting to the emergency department. In this retrospective, observational analysis, all patients with low to intermediate pre-test probability receiving D-dimer measurement and computed tomography angiography (CTA) to rule out pulmonary embolism between January 2017 and December 2020 were included. Previously defined renal function-adjusted D-dimer cutoffs (1306 µg/l for moderate and 1663 µg/l for severe renal function impairment) were applied to determine sensitivity, specificity, negative and positive predictive values. One thousand, three hundred sixty-nine patients were included of which 229 (17%) were diagnosed with pulmonary embolism. The estimated glomerular filtration rate (eGFR) was ≥ 60 ml/min in 1079 (79%), 30-59 ml/min in 266 (19%) and < 30 ml/min in 24 (2%) patients. Only three patients (1.1%) with an eGFR < 60 ml/min had a D-dimer level < 500 µg/l. There was a significant correlation between D-dimer and eGFR (R = - 0.159, p < 0.001). Calculated on the standard D-dimer cutoff value of 500 µg/l, sensitivity of D-dimer testing was 97% for patients with an eGFR ≥ 60 ml/min and 100% for those with 30-60 ml/min, while specificity decreased in patients with renal function impairment. A negative predictive value of 0.99 as a premise to safely rule out pulmonary embolism was achieved by applying a D-dimer cutoff of 1480 µg/l for eGFR 30-59 ml/min and 1351 µg/l for eGFR < 30 ml/min. The findings of this study underline that application of renal function-adapted D-dimer levels in combination with a clinical prediction rule appears feasible to rule out pulmonary embolism. Out of the current dataset, renal function-adjusted D-dimer cutoffs to rule out pulmonary embolism were slightly different compared to previously defined cutoffs. Further studies on a larger scale are needed to validate possible renal function-adjusted D-dimer cutoffs.

Types of Evidence Needed to Assess the Clinical Value of Diagnostic Imaging

AbstractThe evidence underlying the use of advanced diagnostic imaging is based mainly on diagnostic accuracy studies and not on well-designed trials demonstrating improved patient outcomes. This has led to an expansion of low-value and potentially harmful patient care and raises ethical issues around the widespread implementation of tests with incompletely known benefits and harms. Randomized clinical trials are needed to support the safety and effectiveness of imaging tests and should be required for clearance of most new technologies. Large, diverse cohort studies are needed to quantify disease risk associated with many imaging findings, especially incidental findings, to enable evidence-based management. The responsibility to minimize the use of tests with unknown or low value requires engagement of clinicians, medical societies, and the public.

The History of Diagnosing Venous Thromboembolism

An accurate and prompt diagnosis of deep vein thrombosis and/or pulmonary embolism is important to prevent serious complications and mortality. Because the clinical presentation of venous thromboembolism (VTE) is often nonspecific, objective testing by means of radiological imaging is required to confirm the diagnosis. Historically, a diagnosis of VTE involved invasive imaging techniques like contrast venography or conventional pulmonary angiography. Technological developments toward more accurate and less invasive diagnostics have driven the implementation of a variety of newer technologies over the past decades, as well as the derivation and validation of clinical decision rules (CDRs) that can be used to rule out VTE in combination with D-dimer blood tests. In this narrative review, we provide a historical overview of the most notable developments in the imaging techniques and CDRs for VTE diagnosis.

Utility of ultrasound in the diagnostic work-up of suspected pulmonary embolism: an open-label multicentre randomized controlled trial (the PRIME study)

Background

Prevalence of pulmonary embolism (PE) in patients referred to diagnostic imaging is decreasing, indicating a need for improving patient selection. The aim of this study was to assess reduction in referral to diagnostic imaging by integrating a bespoke ultrasound protocol and describe associated failure rate and adverse events in patients with suspected PE.

Methods

In a randomized open-label multicentre trial spanning June 18, 2021, through Feb 1, 2023, adult patients with suspected PE and 1) a Wells score of 0-6 and elevated age-adjusted D-dimer or 2) Wells score >6 were randomly assigned 1:1 to direct diagnostic imaging (controls) or focused lung, cardiac, and deep venous ultrasound by unblinded investigators. Ultrasound could: 1) dismiss PE if no signs of PE and low clinical suspicion or an alternate diagnosis, 2) confirm PE in case of visible venous thrombus, ≥2 subpleural infarctions, McConnell's, or D-sign, or 3) refer to diagnostic imaging if neither category was fulfilled or a patient with confirmed PE by ultrasound required admission. Primary endpoint was proportion of patients referred to diagnostic imaging. Outcome assessors were not blinded to group assignment. All included participants were included in safety analyses. The trial was registered at clinicaltrials.gov (NCT04882579).

Findings

A total of 150 patients were recruited, of whom 73 were randomized to ultrasound. Among 77 controls referred to diagnostic imaging, 26 patients had PE confirmed. In the ultrasound group, 40 patients were referred to diagnostic imaging of whom 20 had PE, reducing referral for diagnostic imaging by 45.2% (95% CI: 34.3-56.6, p < 0.0001). Three further PEs were diagnosed by presence of a DVT. During 3-month follow-up, the number of patients who did not receive anticoagulation but was diagnosed with PE was two (4%; 95% CI: 1.1-13.5) and none (0%; 95% CI: 0.0-7.0) in the ultrasound and control group, respectively.

Interpretation

Ultrasound substantially reduced referral to diagnostic imaging in suspected PE. Albeit with an unacceptable failure rate.

Funding

University of Southern Denmark, Odense University Hospital, Master Carpenter Sophus Jacobsen and wife's foundation, Engineer K. A. Rhode and wife foundation.

Diagnosis of Pulmonary Embolism: A Review of Evidence-Based Approaches

Venous thromboembolism, commonly presented as pulmonary embolism and deep-vein thrombosis, is a paramount and potentially fatal condition with variable clinical presentation. Diagnosis is key to providing appropriate treatment in a safe and timely fashion. Clinical judgment and assessment using clinical scoring systems should guide diagnostic testing, including laboratory and imaging modalities, for optimal results and to avoid unnecessary testing.

Hemostasis Testing in the Emergency Department: A Narrative Review

Routine laboratory screening is typically performed at initial evaluation of the vast majority of presentations to the emergency department (ED). These laboratory results are crucial to the diagnostic process, as they may influence up to 70% of clinical decisions. However, despite the usefulness of biological assessments, many tests performed are inappropriate or of doubtful clinical relevance. This overutilization rate of laboratory testing in hospitals, which represents a significant medical-economic burden, ranges from 20 to 67%, with coagulation tests at the top of the list. While reviews frequently focus on nonintensive care units, there are few published assessments of emergency-specific interventions or guidelines/guidance to date. The aim of this review is to highlight current recommendations for hemostasis evaluation in the emergency setting with a specific analysis of common situations leading to ED admissions, such as suspected venous thrombosis or severe bleeding. We revisit the evidence related to the assessment of patient's hemostatic capacity based on comprehensive history taking and physical examination as well as best practice recommendations for blood sample collection to ensure the reliability of results. This review also includes an examination of various currently available point of care tests and a comprehensive discussion on indications, limitations, and interpretation of these tests.

Age-Adjusted and Clinical Probability Adapted D-Dimer Cutoffs to Rule Out Pulmonary Embolism: A Narrative Review of Clinical Trials

Diagnosis of pulmonary embolism remains a challenge for clinicians as its differential diagnosis is wide. The use of sequential diagnostic strategies based on the assessment of clinical probability, D-dimer measurement, and computed tomography pulmonary angiography have been validated in large prospective outcome studies. D-dimer measurement at a standard cutoff of 500 μg/L has gained wide acceptance to rule out pulmonary embolism in around 20 to 30% of patients with a clinically suspected pulmonary embolism. To improve the efficiency of D-dimer measurement, different ways of selecting a higher, albeit safe cutoff were explored: the age-adjusted D-dimer cutoff and the clinical adapted D-dimer cutoff. While both have been prospectively validated in large studies, some differences do exist. In particular, the prevalence of pulmonary embolism in these different validation studies was very different. Overall, the age-adjusted cutoff seems to be safer and less efficient, while the clinical probability adapted cutoff seems more efficient and less safe. Here, we report the available data regarding these two different ways to increase the diagnostic yield of D-dimer. Also, well beyond the accuracy of these adjusted/adapted cutoffs, some external factors, such as the prevalence of pulmonary embolism in the tested population and the clinical setting, have an important impact of the negative predictive value and on the overall efficiency of these cutoffs. Therefore, we also discuss which cutoff should be used according to the expected prevalence of the disease and according to the clinical setting.

Subsegmental Pulmonary Embolism

Subsegmental pulmonary embolism (SSPE) is increasingly diagnosed with the growing use and technological advancements of multidetector computed tomography pulmonary angiography. Its diagnosis is challenging, and some presumed SSPE may actually represent imaging artifacts. Indirect evidence and results from small observational studies suggest that SSPE may be more benign than more proximal pulmonary embolism, and may thus not always require treatment. Therefore, guidelines suggest to consider a management strategy without anticoagulation in selected patients with SSPE at low risk of recurrent venous thromboembolism (VTE), in whom proximal deep vein thrombosis is excluded. Recently, a large prospective study among low-risk patients with SSPE who were left untreated showed a higher VTE recurrence risk than initially deemed acceptable by the investigators, and thus was prematurely interrupted after recruitment of 97% of the target population. However, the risk-benefit ratio of anticoagulation for low-risk patients with SSPE remains unclear, and results from randomized trials are needed to answer the question about their optimal management.

Diagnostic Strategies in Pulmonary Embolism

Key to the diagnosis of pulmonary embolism (PE) is a careful bedside evaluation. After this, there are three further diagnostic steps. In all patients, estimation of the clinical probability of PE is performed. The other two steps are measurement of D-dimer when indicated and chest imaging when indicated. The clinical probability of PE is estimated at low, moderate, or high. The prevalence of PE is less than 15% among patients with low clinical probability, 15 to 40% with moderate clinical probability, and >40% in patients with high clinical probability. Clinical gestalt has been found to be very useful in estimating probability of PE. However, clinical prediction rules, such as Wells criteria, the modified Geneva score, and the PE rule out criteria have been advocated as adjuncts. In patients with high clinical probability, the high prevalence of PE can lower the D-dimer negative predictive value, which could increase the risk of diagnostic failure. Consequently, patients with high probability for PE need to proceed directly to chest imaging, without prior measurement of D-dimer level. Key studies in determining which low to moderate probability patients require chest imaging are the Age-adjusted D-dimer cutoff levels to rule out pulmonary embolism (ADJUST-PE), the Simplified diagnostic management of suspected pulmonary embolism (YEARS), and the Pulmonary Embolism Graduated D-Dimer trials. In patients with low clinical probability, PE can be excluded without imaging studies if D-dimer is less than 1,000 ng/mL. In patients in whom there is not a low likelihood for PE, this can be excluded without imaging studies if the D-dimer is below the age-adjusted threshold.

Tutorial: dos and don'ts in clinical prediction research for venous thromboembolism

Clinical prediction modeling has become an increasingly popular domain of venous thromboembolism research in recent years. Prediction models can help healthcare providers make decisions regarding starting or withholding therapeutic interventions, or referrals for further diagnostic workup, and can form a basis for risk stratification in clinical trials. The aim of the current guide is to assist in the practical application of complicated methodological requirements for well-performed prediction research by presenting key dos and don'ts while expanding the understanding of predictive research in general for (clinical) researchers who are not specifically trained in the topic; throughout we will use prognostic venous thromboembolism scores as an exemplar.

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.

Dust particulate matter increases pulmonary embolism onset: A nationwide time-stratified case-crossover study in China

BACKGROUND

Particulate matter (PM) has been found to elevate the risk of pulmonary embolism (PE) onset. Among the contributors to PM, dust PM stands as the second natural source, and its emissions are escalating due to climate change. Despite this, information on the effect of dust PM on PE onset is scarce. Hence, this study aims to investigate the impacts of dust PM10, dust PM2.5-10, and dust PM2.5 on PE onset.

METHODS

A nationwide time-stratified case-crossover study was conducted between 2015 and 2020, using data from 18,616 PE onset cases across 1,921 hospitals in China. The analysis employed a conditional logistic regression model to quantify the associations between dust PM10, dust PM2.5-10, and dust PM2.5 and PE onset. Furthermore, the study explored the time-distributed lag pattern of the effect of dust PM on PE development. Stratified analyses were performed based on sex, age, region, and season.

RESULTS

Dust PM10, dust PM2.5-10, and dust PM2.5 exhibited significant health effects on PE onset, particularly concerning exposure on the same day. The peak estimates were observed at lag 01 day, with the odds ratio being 1.011 [95 % confidence interval (CI): 1.003, 1.019], 1.014 (95 % CI: 1.003, 1.026), and 1.039 (95 % CI: 1.011, 1.068), for a 10 μg/m3 increase in the concentration of dust PM10, dust PM2.5-10, and dust PM2.5, respectively. In addition, the study identified a higher risk of PE onset associated with dust PM exposure during the warm season than that in cool season, particularly for dust PM2.5.

CONCLUSIONS

The findings from this study suggest that short-term exposure to dust PM, particularly dust PM2.5, may trigger PE onset, posing a significant health threat. Implementing measures to mitigate dust PM emissions and protect patients with PE from dust PM exposure is imperative.

Diagnostic strategies in postpartum individuals with suspected venous thromboembolism: A scoping review

BACKGROUND

The risk of venous thromboembolism (VTE) is increased postpartum and contributes to important morbidity and mortality. While there have been advances in evaluating diagnostic algorithms for suspected VTE during pregnancy, there is limited data for postpartum individuals.

OBJECTIVE

We conducted a scoping review to describe and evaluate diagnostic strategies used to investigate suspected VTE in postpartum individuals.

METHODS

A comprehensive search strategy was conducted in Ovid MEDLINE, Embase and the Cochrane Central Register of Controlled Trials (January 1, 2000-September 30, 2022) to identify original articles that reported on diagnostic strategies in postpartum individuals with suspected VTE. We extracted demographics, clinical decision rules used, D-dimer and imaging completed, including test performance and VTE outcomes.

RESULTS

A total of 13 studies conducted across 11 countries with separate postpartum data were included for 759 individuals with suspected PE (n = 634) or DVT (n = 125), including unpublished data (n = 251). Among those with suspected PE, computed tomography pulmonary angiography was conducted more commonly (n = 522) than ventilation-perfusion scans (n = 69), with PE positivity rates that ranged from 4 %-27.6 % and 0-50 % across studies, respectively. Among 131 postpartum individuals with suspected PE who had a D-dimer measured, only 4.6 % (6/131) had a negative D-dimer test. For postpartum individuals with suspected DVT, the most common diagnostic test was compression ultrasonography (positivity rate 12.2 %-18.6 %). There were limited retrospective data evaluating the clinical decision rules.

CONCLUSIONS

There are heterogeneous approaches globally in the diagnosis of suspected postpartum VTE. Limited high-quality data available underscores the need for more robust evidence to inform clinical practice.

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.

The thrombotic risk in Cushing's syndrome-questions, answers, and the algorithm to consider in its assessment: part I-thrombotic risk not related to surgery

Introduction

Recently, it has been reported that there is a great diversity in strategies used for thromboprophylaxis in patients with Cushing's syndrome (CS). An aim of this review was to discuss these practices in light of the existing data on the thrombotic risk in patients with CS and guidelines for medically ill patients.

Methods

The four relevant topics and questions on thrombotic risk in CS were identified. The current guidelines on prevention and diagnosis of venous thromboembolism (VTE) were reviewed for the answers. An algorithm to consider in the assessment of the thrombotic risk in patients with CS was proposed.

Results

To address both generic and CS-specific risk factors for VTE, the algorithm includes the stepwise approach consisting of Padua Score, urine free cortisol, and CS-VTE score, with no indication for routine thrombophilia testing in the prediction of an index VTE episode. Having confirmed VTE, selected patients require thrombophilia testing to aid the duration of anticoagulant treatment. The separate part of the algorithm is devoted to patients with ectopic adrenocorticotropic hormone syndrome in whom exclusion of VTE precedes introducing routine thromboprophylaxis to prevent VTE. The cancer-related VTE also prompts thromboprophylaxis, with the possible vessel invasion. The algorithm presents a unifactorial and multifactorial approach to exclude high-bleeding risks and safely introduce thromboprophylaxis with low-molecular-weight heparin.

Summary

Our article is the first to present an algorithm to consider in the thrombotic risk assessment among patients with Cushing's syndrome as a starting point for a broader discussion in the environment. A plethora of factors affect the VTE risk in patients with CS, but no studies have conclusively evaluated the best thromboprophylaxis strategy so far. Future studies are needed to set standards of care.

D-dimer Levels for the exclusion of pulmonary embolism: making sense of international guideline recommendations

Several international guidelines provide recommendations around the use of D-dimer testing for exclusion of pulmonary embolism, including the appropriate D-dimer threshold (or cutoff), but there is no consensus among them. We briefly discuss guideline variation, performance characteristics, and limitations of commercially available D-dimer assays in this setting, referencing the Clinical and Laboratory Standards Institute guidelines that recommend immunoassays with high sensitivity (≥97%) and negative predictive value (≥98%). While age-adjusted D-dimer and pretest-adjusted D-dimer are considered a safe strategy across predefined patient subgroups, clinicians need to recognize the different performance characteristics of D-dimer assays to enable safe clinical decisions for their patients. Importantly, D-dimer values must be correlated not only to clinical findings but also interpreted within the context of the accuracy and precision of the specific testing modality, adhering to manufacturer specifications that are approved by regulatory authorities.

Presence of procoagulant peripheral blood mononuclear cells in severe COVID-19 patients relate to ventilation perfusion mismatch and precede pulmonary embolism

PURPOSE

Pulmonary emboli (PE) contribute substantially to coronavirus disease 2019 (COVID-19) related mortality and morbidity. Immune cell-mediated hyperinflammation drives the procoagulant state in COVID-19 patients, resulting in immunothrombosis. To study the role of peripheral blood mononuclear cells (PBMC) in the procoagulant state of COVID-19 patients, we performed a functional bioassay and related outcomes to the occurrence of PE. Secondary aims were to relate this functional assay to plasma D-dimer levels, ventilation perfusion mismatch and TF expression on monocyte subsets.

METHODS

PBMC from an ICU biobank were obtained from 20 patients with a computed tomography angiograph (CTA) proven PE and compared to 15 COVID-19 controls without a proven PE. Functional procoagulant properties of PBMC were measured using a modified fibrin generation time (MC-FGT) assay. Tissue factor (TF) expression on monocyte subsets were measured by flow cytometry. Additional clinical data were obtained from patient records including end-tidal to arterial carbon dioxide gradient.

RESULTS

MC-FGT levels were highest in the samples taken closest to the PE detection, similar to the end-tidal to arterial carbon dioxide gradient (ETCO2 - PaCO2), a measurement to quantify ventilation-perfusion mismatch. In patients without proven PE, peak MC-FGT relates to an increase in end-tidal to arterial carbon dioxide gradient. We identified non-classical, CD16 positive monocytes as the subset with increased TF expression.

CONCLUSION

We show that the procoagulant state of PBMC could aid in early detection of PE in COVID-19 ICU patients. Combined with end-tidal to ETCO2 - PaCO2 gradient, these tests could improve early detection of PE on the ICU.

Values of Caprini Risk Assessment Scale and D-Dimer for Predicting Venous Thromboembolism During Puerperium

Purpose

To evaluate the predictive value of the combination of the Caprini risk assessment model (RAM) and D-dimer for venous thromboembolism (VTE) during puerperium.

Patients and Methods

This was a retrospective case-control study. Thirty-one puerperium patients with VTE were included as cases, and 279 puerperium women without VTE were matched to cases according to age, number of fetuses, birth day and delivery mode at the ratio of 9:1. Demographic data, clinical data and laboratory parameters within postpartum 24 h were collected. Multivariate analysis, employing the forward stepwise model, was conducted to identify independent factors associated with VTE during puerperium. The predictive values of Caprini RAM, D-dimer and their combination were evaluated using receiver operating characteristic (ROC) curve, and the area under curve (AUC) was compared using Z test.

Results

Univariate analysis demonstrated that there were significant differences in D-dimer levels, Caprini score, scarred uterus, adherent placenta, postpartum hemorrhage and intrauterine infection between cases and controls (P<0.05). Multivariate analysis demonstrated that D-dimer levels (OR: 1.754, 95% CI: 1.237-3.182), Caprini score (OR: 1.209, 95% CI: 1.058-2.280), scarred uterus (OR: 1.978, 95% CI: 1.258-3.794), postpartum hemorrhage (OR: 2.276, 95% CI: 1.334-4.347) and intrauterine infection (OR: 2.575, 95% CI: 1.463-4.618) were independently associated with VTE during puerperium with adjustment for adherent placenta and fetal birth weight. The AUCs of D-dimer levels, Caprini score and their combination were 0.748 (SE: 0.030, 95% CI: 0.688-0.807), 0.647 (SE: 0.035, 95% CI: 0.578-0.716) and 0.840 (SE: 0.025, 95% CI: 0.791-0.888). Combination prediction had a higher AUC compared with that of independent prediction (0.840 vs 0.748, Z=2.356, P=0.009; 0.840 vs 0.647, Z=4.487, P<0.001) with a sensitivity of 83.9% and specificity of 80.3%.

Conclusion

The combination of the Caprini RAM and D-dimer could significantly elevate the predictive value for VTE during puerperium, and this new tool had the potential in the prediction of VTE during puerperium.

ERS International Congress 2023: highlights from the Pulmonary Vascular Diseases Assembly

Pulmonary vascular diseases such as pulmonary embolism and pulmonary hypertension are important and frequently under-recognised conditions. This article provides an overview of key highlights in pulmonary vascular diseases from the European Respiratory Society International Congress 2023. This includes insights into disease modification in pulmonary arterial hypertension and novel therapies such as sotatercept and seralutinib. Exciting developments in our understanding of the mechanisms underpinning pulmonary hypertension associated with interstitial lung disease are also explored. A comprehensive overview of the complex relationship between acute pulmonary embolism and chronic thromboembolic pulmonary hypertension (CTEPH) is provided along with our current understanding of the molecular determinants of CTEPH. The importance of multidisciplinary and holistic care cannot be understated, and this article also addresses advances beyond medication, with a special focus on exercise training and rehabilitation.

D-dimer diagnostics: can I use any D-dimer assay? Bridging the knowledge-to-action gap

A State of the Art lecture titled "D-dimer Diagnostics: Can I use any D-dimer assay? Bridging the Knowledge-to-Action gap" was presented at the International Society on Thrombosis and Haemostasis Congress in 2023, included in the session on the clinical impact of variability in commonly used coagulation assays. Here, we review the role of D-dimer, primarily in the outpatient diagnosis of patients with venous thromboembolism (VTE) when combined with clinical decision rules. We focus on the recent large management trials that have studied adjustments of VTE exclusion thresholds for D-dimer based on either prior clinical probability of VTE or patient age, and the resultant benefit of reduced imaging for VTE and improved diagnostic efficiency. In this context, we report on the significant variability between D-dimer results and the multiple D-dimer assays in use worldwide using data from international external quality assurance programs. This variability is particularly high at typical VTE exclusion thresholds. We discuss the potential clinical impact of D-dimer assay substitution on accuracy of diagnosis and risk stratification of patients with VTE. Finally, we summarize relevant new data on this topic presented during the 2023 International Society on Thrombosis and Haemostasis Congress and outline future priorities urgently needed to harmonize D-dimer results and reporting that will require international collaboration among multiple stakeholders with an overall goal to close this knowledge-to-action gap.

An artificial intelligence algorithm for pulmonary embolism detection on polychromatic computed tomography: performance on virtual monochromatic images

OBJECTIVES

Virtual monochromatic images (VMI) are increasingly used in clinical practice as they improve contrast-to-noise ratio. However, due to their different appearances, the performance of artificial intelligence (AI) trained on conventional CT images may worsen. The goal of this study was to assess the performance of an established AI algorithm trained on conventional polychromatic computed tomography (CT) images (CPI) to detect pulmonary embolism (PE) on VMI.

METHODS

Paired 60 kiloelectron volt (keV) VMI and CPI of 114 consecutive patients suspected of PE, obtained with a detector-based spectral CT scanner, were retrospectively analyzed by an established AI algorithm. The CT pulmonary angiography (CTPA) were classified as positive or negative for PE on a per-patient level. The reference standard was established using a comprehensive method that combined the evaluation of the attending radiologist and three experienced cardiothoracic radiologists aided by two different detection tools. Sensitivity, specificity, positive and negative predictive values and likelihood ratios of the algorithm on VMI and CPI were compared.

RESULTS

The prevalence of PE according to the reference standard was 35.1% (40 patients). None of the diagnostic accuracy measures of the algorithm showed a significant difference between CPI and VMI. Sensitivity was 77.5% (95% confidence interval (CI) 64.6-90.4%) and 85.0% (73.9-96.1%) (p = 0.08) on CPI and VMI respectively and specificity 96.0% (91.4-100.0%) and 94.6% (89.4-99.7%) (p = 0.32).

CONCLUSIONS

Diagnostic performance of the AI algorithm that was trained on CPI did not drop on VMI, which is reassuring for its use in clinical practice.

CLINICAL RELEVANCE STATEMENT

A commercially available AI algorithm, trained on conventional polychromatic CTPA, could be safely used on virtual monochromatic images. This supports the sustainability of AI-aided detection of PE on CT despite ongoing technological advances in medical imaging, although monitoring in daily practice will remain important.

KEY POINTS

• Diagnostic accuracy of an AI algorithm trained on conventional polychromatic images to detect PE did not drop on virtual monochromatic images. • Our results are reassuring as innovations in hardware and reconstruction in CT are continuing, whilst commercial AI algorithms that are trained on older generation data enter healthcare.