Computed Tomography Pulmonary Angiography Research Articles

Challenges, Recommendations, and Epidemiology of Pulmonary Embolism in India: A Narrative Review.

An embolized clot that travels to the lungs from the legs or, less commonly, other parts of the body (known as deep vein thrombosis or DVT) causes pulmonary embolism (PE), which is characterized by obstruction of blood flow to the pulmonary artery. As PE has the propensity to masquerade as various illnesses affecting both the cardiovascular (CV) and the respiratory system, it is crucial to identify PE at the earliest. Appropriate diagnosis of PE may lead to earlier treatment and improved patient outcomes. While pulmonary angiography remains the established gold standard for diagnosing PE, the contemporary standard of care for this condition is the computed tomography pulmonary angiogram (CTPA). Anticoagulation therapy is the fundamental strategy for managing PE, with the forefront of treatment being the use of novel and upcoming oral anticoagulants known as non-vitamin K antagonist oral anticoagulants (NOACs). The NOACs provide a practical single-drug treatment strategy, which does not hinder the patient's lifestyle and domestic responsibilities. Although PE may be fatal, early detection may lead to effective management. Despite that, mortality and morbidity associated with PE are very high in India. The awareness among Indian healthcare professionals about PE should be improved, and unified pan-country diagnostic and management guidelines should be formulated to tackle the country's PE burden.

Can a negative d-dimer rule out pulmonary embolism in patients with COVID-19?

BackgroundGlobally, there have been more than 771 million confirmed cases of COVID-19 and more than 6.9 million deaths. The relationship between Covid-19 and pulmonary embolism (PE) has been well-established. ObjectivesWe evaluated the correlation between normal D-dimer levels and negative findings on computed tomography pulmonary angiogram (CTPA) to assess its predictive value. Additionally, we determined the sensitivity and specificity of a D-dimer in COVID-19 (+) patients. MethodsThis was a retrospective cohort study of all adult patients presenting to one of 17 EDs within a large integrated healthcare system between March 1, 2020, and December 31, 2021, who were diagnosed with COVID-19 and had a D-dimer and CTPA as part of their clinical workup. This study includes EDs in urban, suburban, and rural areas. Sensitivity and specificity were calculated to assess the performance of D-dimer tests in discriminating those with and without PE. Multiple logistic regression was used to assess the effect of D-dimer test results in predicting PE. ResultsA total of 3133 patients were included in this study (Fig. 1). Of 3133 patients, 2846 (91 ​%) had an abnormal D-dimer, and 287 (9 ​%) had a normal D-dimer. In the group with the abnormal D-dimer, 145 (5 ​%) had a PE on CTPA. In the group with the normal D-dimer, 285 (99.3 ​%) patients did not have a PE on CTPA. The sensitivity of D-dimer in this population was 98.6 ​%, and the specificity was 9.5 ​%. Patients with abnormal D-dimer levels were 7.86 times more likely to have a PE. ConclusionIn conclusion, our study found that PE could be safely excluded for COVID-19 (+) patients with a normal or age-adjusted D-dimer.

Age-Adjusted D-Dimer Cutoff in Ruling Out Pulmonary Embolism among Saudi Arabians in Riyadh Province

Objective. The study aimed to investigate the effectiveness of an age-adjusted D-dimer (AADD) cutoff in ruling out pulmonary embolism (PE) among the Saudi population, addressing the lack of data on AADD utility in this demographic. Methods. This single-centre retrospective cohort study conducted at Department of Medicine, King Abdulaziz Medical City in Riyadh, Saudi Arabia, between 2010 and 2018 analysed the data from patients suspected of PE who underwent computed tomography pulmonary angiography (CTPA). Age-adjusted D-dimer (AADD) levels were calculated for patients over 50 years of age [(age×10) µg/L], and AADD cutoffs were compared for diagnostic accuracy. Results. Among 277 subjects meeting inclusion criteria, a significant association between D-dimer levels and PE presence was observed. The AADD criteria showed a specificity of 94.7% and a sensitivity of 25%, with a Youden index of 0.2. The high negative predictive value of 90.62% supported the use of AADD in confirming the absence of PE in patients. Conclusions. Based on the study findings, the AADD cutoff [(age×10) µg/L] can be efficiently and safely used as an exclusionary tool for patients over 50 years of age suspected of having PE. This study supports the clinical utility of AADD, particularly in older Saudi patient populations.

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

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. 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. 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. 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.

Predicting the Prognosis of Acute Pulmonary Embolism Using Computed Tomography Pulmonary Angiography Measurable Parameters in Comparison to Pulmonary Embolism Severity Index (PESI)

Abstract Background Pulmonary embolism is a leading cause of cardiovascular death and with CTPA being the gold standard in its diagnosis, it is feasible with radiologic parameters to stratify and early identify patients at risk of death. Aim of the Work To detect the prognostic value of radiologic parameters of CT pulmonary angiography (CTPA) in comparison to pulmonary embolism severity index (PESI). Patients and Methods This was a prospective study done at Ain Shams University Hospitals and included 84 patients diagnosed with acute pulmonary embolism and referred to the radio-diagnosis department for CT pulmonary angiography examination. Results 3.6% of patients died within 24 hours and 44% died within 30 days of diagnosis of PE. All patients who died within 30 days had abnormal CTPA findings especially RV/LV ratio, PT diameter, septal bowing and contrast reflux in the IVC which revealed significant relationship between them and 30-day-mortality. Meanwhile PESI showed contradictory results and was less reliable than the radiologic parameters. Conclusion The CTPA radiological parameters appeared valuable for the prediction of 30-day mortality in patients with acute PE, and was superior to the PESI.

Low-dose tenecteplase during cardiopulmonary resuscitation in massive pulmonary embolism

We report the case of an 18-year-old male who presented to the Emergency Department with sudden onset dyspnea. The patient was intubated on arrival, but suffered a cardiac arrest soon after. Point-of-care echocardiography during cardiopulmonary resuscitation revealed a grossly dilated right atrium and right ventricle, which alerted the Emergency physician to the possibility of massive pulmonary embolism leading to cardiac arrest. Due to no discernible history or risk factors in favour of pulmonary embolism, a decision was taken for thrombolysis with half dose Tenecteplase. Return of spontaneous circulation was achieved 14 min after thrombolysis, with massive pulmonary embolism subsequently being confirmed on CT Pulmonary Angiography.

Cardiopulmonary Complications after Pulmonary Embolism in COVID-19.

Although pulmonary embolism (PE) is a frequent complication in COVID-19, its consequences remain unknown. We performed pulmonary function tests, echocardiography and computed tomography pulmonary angiography and identified blood biomarkers in a cohort of consecutive hospitalized COVID-19 patients with pneumonia to describe and compare medium-term outcomes according to the presence of PE, as well as to explore their potential predictors. A total of 141 patients (56 with PE) were followed up during a median of 6 months. Post-COVID-19 radiological lung abnormalities (PCRLA) and impaired diffusing capacity for carbon monoxide (DLCOc) were found in 55.2% and 67.6% cases, respectively. A total of 7.3% had PE, and 6.7% presented an intermediate-high probability of pulmonary hypertension. No significant difference was found between PE and non-PE patients. Univariate analysis showed that age > 65, some clinical severity factors, surfactant protein-D, baseline C-reactive protein, and both peak red cell distribution width and Interleukin (IL)-10 were associated with DLCOc < 80%. A score for PCRLA prediction including age > 65, minimum lymphocyte count, and IL-1β concentration on admission was constructed with excellent overall performance. In conclusion, reduced DLCOc and PCRLA were common in COVID-19 patients after hospital discharge, but PE did not increase the risk. A PCRLA predictive score was developed, which needs further validation.

Performance and clinical utility of an artificial intelligence-enabled tool for pulmonary embolism detection

PurposeDiagnosing pulmonary embolism (PE) is still challenging due to other conditions that can mimic its appearance, leading to incomplete or delayed management and several inter-observer variabilities. This study evaluated the performance and clinical utility of an artificial intelligence (AI)-based application designed to assist clinicians in the detection of PE on CT pulmonary angiography (CTPA). Patients and methodsCTPAs from 230 US cities acquired on 57 scanner models from 6 different vendors were retrospectively collected. Three US board certified expert radiologists defined the ground truth by majority agreement. The same cases were analyzed by CINA-PE, an AI-driven algorithm capable of detecting and highlighting suspected PE locations. The algorithm's performance at a per-case and per-finding level was evaluated. Furthermore, cases with PE not mentioned in the clinical report but correctly detected by the algorithm were analyzed. ResultsA total of 1204 CTPAs (mean age 62.1 years ± 16.6[SD], 44.4 % female, 14.9 % positive) were included in the study. Per-case sensitivity and specificity were 93.9 % (95%CI: 89.3 %–96.9 %) and 94.8 % (95%CI: 93.3 %–96.1 %), respectively. Per-finding positive predictive value was 89.5 % (95%CI: 86.7 %–91.9 %). Among the 196 positive cases, 29 (15.6 %) were not mentioned in the clinical report. The algorithm detected 22/29 (76 %) of these cases, leading to a reduction in the miss rate from 15.6 % to 3.8 % (7/186). ConclusionsThe AI-based application may improve diagnostic accuracy in detecting PE and enhance patient outcomes through timely intervention. Integrating AI tools in clinical workflows can reduce missed or delayed diagnoses, and positively impact healthcare delivery and patient care.

COPD Subtypes Are Differentially Associated With Cardiovascular Events and COPD Exacerbations

The coronary artery calcium score (CACS) and ratio of the pulmonary artery to aorta diameters (PA:A ratio) measured from chest CT scans have been established as predictors of cardiovascular events and COPD exacerbations, respectively. However, little is known about the reciprocal relationship between these predictors and outcomes. Furthermore, the prognostic implications of COPD subtypes on clinical outcomes remain insufficiently characterized. How can these two chest CT scan-derived parameters predict subsequent cardiovascular events and COPD exacerbations in different COPD subtypes? Using COPDGene study data, we assessed prospective cardiovascular disease (CVD) and COPD exacerbation risk in patients with COPD (Global Initiative for Chronic Obstructive Lung Disease spirometric grades 2-4), focusing on CACS and PA:A ratio at study enrollment, with logistic regression models. These outcomes were analyzed in three COPD subtypes: 1,042 patients with non-emphysema-predominant disease (NEPD) (low attenuation area at-950 Hounsfield units [LAA-950]< 5%), 1,324 patients with emphysema-predominant disease (EPD) (LAA-950≥ 10%), and 465 patients with intermediate emphysema disease (5%≤ LAA-950< 10%). Our study indicated significantly higher overall risk for cardiovascular events in patients with higher CACS (≥ median; OR, 1.61; 95%CI, 1.30-2.00) and increased COPD exacerbations in those with higher PA:A ratios (≥ 1; OR, 1.80; 95%CI, 1.46-2.23). Notably, patients with NEPD showed a stronger association between these indicators and clinical events than those with EPD (with CACS/CVD, NEPD vsEPD: OR, 2.02 vs1.41; with PA:A ratio/COPD exacerbation, NEPD vsEPD: OR, 2.50 vs1.65); the difference in ORs between COPD subtypes was statistically significant for CACS/CVD. Two chest CT scan parameters, CACS and PA:A ratio, hold distinct predictive values for cardiovascular events and COPD exacerbations that are influenced by specific COPD subtypes. ClinicalTrials.gov; No.: NCT00608764; URL: www. gov.

Pulmonary embolism in patients with chronic coronary syndrome masquerading as acute coronary syndrome: a case report and literature review

BackgroundPulmonary embolisms (PEs) exhibit clinical features similar to those of acute coronary syndrome (ACS), including electrocardiographic abnormalities and elevated troponin levels, which frequently lead to misdiagnoses in emergency situations.Case presentationHere, we report a case of PE coinciding with chronic coronary syndrome in which the patient’s condition was obscured by symptoms mimicking ACS. A 68-year-old female with syncope presented to the hospital. Upon admission, she was found to have elevated troponin levels and an electrocardiogram showing ST-segment changes across multiple leads, which initially led to a diagnosis of ACS. Emergency coronary arteriography revealed occlusion of the posterior branches of the left ventricle of the right coronary artery, but based on the complexity of the intervention, the occlusion was considered chronic rather than acute. On the 3rd day after admission, the patient experienced recurrent chest tightness and shortness of breath, which was confirmed as acute PE by emergency computed tomography pulmonary angiography. Following standardized anticoagulation treatment, the patient improved and was subsequently discharged.ConclusionsThis case report highlights the importance of recognizing the nonspecific features of PE. Clinicians should be vigilant when identifying other clinical features that are difficult to explain accompanying the expected disease, and it is necessary to carefully identify the causes to prevent missed diagnoses or misdiagnoses.

Stopping anticoagulation for isolated or incidental pulmonary embolism: the STOPAPE RCT protocol.

Is withholding anticoagulation for patients with isolated or incidental subsegmental pulmonary embolism clinically and cost-effective compared with full anticoagulation for 3 months? There has been an increase in the diagnosis of subsegmental pulmonary embolism since the advent of computed tomography pulmonary angiogram to investigate patients with suspected pulmonary embolism. Subsegmental pulmonary embolism is not often detectable with older nuclear medicine-based diagnostic imaging for ventilation/perfusion mismatch. The case fatality of pulmonary embolism has reduced as subsegmental pulmonary embolism diagnoses from computed tomography pulmonary angiogram have increased. There is growing equipoise about the optimal treatment for patients with subsegmental pulmonary embolism, given that full anticoagulation has significant risks of bleeding and subsegmental pulmonary embolism was not often diagnosed previously with ventilation/perfusion scanning and therefore most likely left predominantly untreated prior to the introduction of computed tomography pulmonary angiogram scanning. Determine whether withholding anticoagulation for isolated or incidental subsegmental pulmonary embolism (i.e. subsegmental pulmonary embolism with no coexisting deep-vein thrombosis) reduces the harms of recurrent thromboembolism and major bleeding compared with 3 months of full anticoagulation at 3, 6 and 12 months. Determine the rate of complications of anticoagulation therapy (predominantly bleeding) in patients with isolated subsegmental pulmonary embolism. Determine whether not treating isolated subsegmental pulmonary embolism is acceptable to clinicians and patients. Determine the reclassification rate of subsegmental pulmonary embolism diagnoses made by general reporting radiologists when reviewed by specialist respiratory radiologists and develop a set of rules to improve general radiologists' diagnoses of subsegmental pulmonary embolism. Assess cost-effectiveness of not treating patients with isolated subsegmental pulmonary embolism with anticoagulation, taking a health service perspective. Prospective individually randomised open controlled trial with blinded end-point committee assessment for outcomes, powered for non-inferiority for recurrent venous thromboembolism and for superiority for bleeding events. An internal pilot phase is included for feasibility and acceptability of no anticoagulation. We planned to recruit 1466 patients from at least 50 acute hospital sites. Allowing for a dropout rate of 15%, this would have given us 90% power to detect a reduction in major and clinically relevant non-major bleeding from 7.3% in the anticoagulation arm to 3% in the intervention arm. We were powered to determine that a strategy of no anticoagulation was non-inferior to anticoagulation with an upper margin of a 2.3% increase in recurrent venous thromboembolism from an expected rate of 2% in those who receive full anticoagulation. We also planned to undertake a study comparing acute reporting radiologists' diagnoses of subsegmental pulmonary embolism from all computed tomography pulmonary angiograms with specialist respiratory radiologists. This would have allowed us to determine safety in the pilot study (i.e. patients with pulmonary embolism that was in fact larger than subsegmental would have been identified) and develop guidance for subsegmental pulmonary embolism diagnosis for general radiologists. Patients with lived experience of thrombosis contributed to all aspects of the trial design and were part of the Trial Management Group. The STOPAPE trial was stopped prematurely due to a low recruitment rate in the wake of the COVID pandemic and prioritisation of recovery of the National Institute for Health and Care Research research portfolio. There are no outcome data available for this trial. Separate NIHR Library publications will detail the linked qualitative study examining the views of patients and clinicians around withholding anticoagulation for isolated subsegmental pulmonary embolism as well as presenting all collected data of recruited patients. This article presents independent research funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme as award number NIHR128073. A plain language summary of this research article is available on the NIHR Journals Library Website https://doi.org/10.3310/HRCW7937.

Automatic detection of pulmonary embolism on computed tomography pulmonary angiogram scan using a three-dimensional convolutional neural network

ObjectiveTo propose a convolutional neural network (EmbNet) for automatic pulmonary embolism detection on computed tomography pulmonary angiogram (CTPA) scans and to assess its diagnostic performance. Methods305 consecutive CTPA scans between January 2019 and December 2021 were enrolled in this study (142 for training, 163 for internal validation), and 250 CTPA scans from a public dataset were used for external validation. The framework comprised a preprocessing step to segment the pulmonary vessels and the EmbNet to detect emboli. Emboli were divided into three location-based subgroups for detailed evaluation: central arteries, lobar branches, and peripheral regions. Ground truth was established by three radiologists. ResultsThe EmbNet’s per-scan level sensitivity, specificity, positive predictive value (PPV), and negative predictive value were 90.9%, 75.4%, 48.4%, and 97.0% (internal validation) and 88.0%, 70.5%, 42.7%, and 95.9% (external validation). At the per-embolus level, the overall sensitivity and PPV of the EmbNet were 86.0% and 61.3% (internal validation), and 83.5% and 57.5% (external validation). The sensitivity and PPV of central emboli were 89.7% and 52.0% (internal validation), and 94.4% and 43.0% (external validation); of lobar emboli were 95.2% and 76.9% (internal validation), and 93.5% and 72.5% (external validation); and of peripheral emboli were 82.6% and 61.7% (internal validation), and 80.2% and 59.4% (external validation). The average false positive rate was 0.45 false emboli per scan (internal validation) and 0.69 false emboli per scan (external validation). ConclusionThe EmbNet provides high sensitivity across embolus locations, suggesting its potential utility for initial screening in clinical practice.

Double left brachiocephalic vein in a paediatric patient with CHD: a case report

AbstractAnomalous brachiocephalic vein (ABCV) is a rare entity of head and neck venous channel variations and malformations. Amongst the five subtypes of ABVC, double left brachiocephalic vein (DLBCV) is the rarest. We present the case of a 1-year-11-month-old syndromic child, who had global developmental delay (GDD) with Sprengel deformity and failure to thrive (suspected Klippel Feil phenotype), who presented to us for the cardiac evaluation. Her 2D echocardiography revealed unobstructed total anomalous supra-cardiac pulmonary venous connection. However, for the delineation of individual pulmonary venous course, CT-pulmonary angiography was advised. CTPA revealed supra-cardiac total anomalous pulmonary venous connection (TAPVC) with incidentally noted DLBCV. Importance of recognition of DLBCV enables us to prevent accidental venous injury during cardiac surgery and to avoid intraoperative technical issues during transvenous pacemaker insertion.

A Literature Review and Case Report Highlighting Pulmonary Artery Pseudoaneurysms Secondary to Uterine Leiomyosarcoma

Pulmonary artery pseudoaneurysm (PAP) is a rare presentation of metastatic neoplasm. The mechanism of formation of PAP is thought to be due to tumor embolus penetration of the vessel wall and the formation of saccular dilation that is more prone to rupture than systemic arterial aneurysms. The leading cause of PAP is infection, and PAP related to neoplasm has rarely been reported. Early diagnosis and treatment are crucial as mortality associated with PAP rupture has been reported from 50-100%. CT pulmonary angiogram is the best approach for diagnosing PAP. Once the diagnosis is confirmed treatment depends on the etiology and clinical condition of the patient, but the favored first-line treatment is endovascular therapy.

Fibrinolysis and clinical outcomes in acute pulmonary embolism. Madras medical college pulmonary embolism (M-PER) registry from India

BackgroundAcute pulmonary embolism (APE) is the third most common cause of vascular death. Data on APE from India and other low-and middle-income countries is sparse. ObjectivesStudy the clinical characteristics, prognostic factors, in-hospital mortality (IMH) and 12 months mortality of patients with APE in India. MethodsWe prospectively enrolled 186 consecutive patients diagnosed with APE between November 2016 and November 2021 in Madras Medical College Pulmonary Embolism Registry (M-PER). All patients had electrocardiography and echocardiography. High risk patients and selected intermediate risk patients underwent fibrinolysis. Results75 % of our patients were below 50 years of age. 35 % were women. The mean time to presentation from symptom onset was 6.04 ± 10.01 days. 92 % had CT pulmonary angiography. Intermediate risk category (61.3 %) was the more common presentation followed by high risk (26.9 %). Electrocardiography showed S1Q3T3 pattern in 56 %. 76 % had right ventricular dysfunction and 12.4 % had right heart thrombi(RHT) by echocardiography. 50.5 % received fibrinolysis. Patients with RHT received fibrinolysis more frequently (78.3 % vs 46.6 %; p = 0.007). In-hospital mortality (IHM) was 15.6 %. Systemic arterial desaturation and need for mechanical ventilation independently predicted IHM. Ten patients (5.3 %) were lost to follow up. One year mortality was 26.7 % (47/176). One year mortality of patients discharged alive was similar among high, intermediate and low risk groups(14.8 % vs 1.9 % vs 10.5 %; p = 0.891). ConclusionsPatients with PE are often young and present late in India. The in-hospital and 12 months mortality were high. Low and intermediate risk groups had a high post discharge mortality similar to high risk patients.

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.

Short-term mortality prediction in acute pulmonary embolism: Radiomics values of skeletal muscle and intramuscular adipose tissue.

Acute pulmonary embolism (APE) is a potentially life-threatening disorder, emphasizing the importance of accurate risk stratification and survival prognosis. The exploration of imaging biomarkers that can reflect patient survival holds the potential to further enhance the stratification of APE patients, enabling personalized treatment and early intervention. Therefore, in this study, we develop computed tomography pulmonary angiography (CTPA) radiomic signatures for the prognosis of 7- and 30-day all-cause mortality in patients with APE. Diagnostic CTPA images from 829 patients with APE were collected. Two hundred thirty-four features from each skeletal muscle (SM), intramuscular adipose tissue (IMAT) and both tissues combined (SM+IMAT) were calculated at the level of thoracic vertebra 12. Radiomic signatures were derived using 10 times repeated three-fold cross-validation on the training data for SM, IMAT and SM+IMAT for predicting 7- and 30-day mortality independently. The performance of the radiomic signatures was then evaluated on held-out test data and compared with the simplified pulmonary embolism severity index (sPESI) score, a well-established biomarker for risk stratification in APE. Predictive accuracy was assessed by the area under the receiver operating characteristic curve (AUC) with a 95% confidence interval (CI), sensitivity and specificity. The radiomic signatures based on IMAT and a combination of SM and IMAT (SM+IMAT) achieved moderate performance for the prediction of 30-day mortality on test data (IMAT: AUC=0.68, 95% CI [0.57-0.78], sensitivity=0.57, specificity=0.73; SM+IMAT: AUC=0.70, 95% CI [0.60-0.79], sensitivity=0.74, specificity=0.54). Radiomic signatures developed for predicting 7-day all-cause mortality showed overall low performance. The clinical signature, that is, sPESI, achieved slightly better performance in terms of AUC on test data compared with the radiomic signatures for the prediction of both 7- and 30-day mortality on the test data (7days: AUC=0.73, 95% CI [0.67-0.79], sensitivity=0.92, specificity=0.16; 30days: AUC=0.74, 95% CI [0.66-0.82], sensitivity=0.97, specificity=0.16). We developed and tested radiomic signatures for predicting 7- and 30-day all-cause mortality in APE using a multicentric retrospective dataset. The present multicentre work shows that radiomics parameters extracted from SM and IMAT can predict 30-day all-cause mortality in patients with APE.

Validation of a pulmonary embolism risk assessment model in gynecological inpatients

ObjectiveTo compare the predictive efficacy of the PADUA and Caprini models for pulmonary embolism (PE) in gynecological inpatients, analyze the risk factors for PE, and validate whether both models can effectively predict mortality rates.MethodsA total of 355 gynecological inpatients who underwent computed tomography pulmonary angiography (CTPA) were included in the retrospective analysis. The comparative assessment of the predictive capabilities for PE between the PADUA and Caprini was carried out using receiver operating characteristic (ROC) curves. Logistic regression analysis was used to identify risk factors associated with PE. Additionally, Kaplan–Meier survival analysis plots were generated to validate the predictive efficacy for mortality rates.ResultsAmong 355 patients, the PADUA and Caprini demonstrated the area under the curve (AUC) values of 0.757 and 0.756, respectively. There was no statistically significant difference in the AUC between the two models (P = 0.9542). Multivariate logistic analysis revealed immobility (P < 0.001), history of venous thromboembolism (VTE) (P = 0.002), thrombophilia (P < 0.001), hormonal treatment (P = 0.022), and obesity (P = 0.019) as independent risk factors for PE. Kaplan–Meier survival analysis demonstrated the reliable predictive efficacy of both the Caprini (P = 0.00051) and PADUA (P = 0.00031) for mortality. ROC for the three- and six-month follow-ups suggested that the Caprini model exhibited superior predictive efficacy for mortality.ConclusionsThe PADUA model can serve as a simple and effective tool for stratifying high-risk gynecological inpatients before undergoing CTPA. The Caprini model demonstrated superior predictive efficacy for mortality rates.

Pulmonary Embolism Diagnosed by CT Pulmonary Angiography in Patients with COVID-19 and Features of the Associated Factors

Background: Since December 2019, when a new coronavirus disease 2019 (COVID-19) was detected in Wuhan, China, over 774 million confirmed COVID-19 cases and over seven million deaths have been reported globally, as of 7 January 2024 (WHO, 2024). Venous thromboembolism is a recognized complication of COVID-19. This study aimed to investigate the prevalence of pulmonary embolism (PE) diagnosed by CT pulmonary angiography (CTPA) in COVID-19 patients and the features of the associated factors. Methods and Results: The study included 162 patients from the Imam Abdulrahman Al-Faisal Hospital who had COVID-19-confirmed infections while hospitalized in the ICU. Patients were diagnosed as COVID-19 positive by RT-PCR and underwent CTPA examination on the Discovery 16-slice CT scanner (Siemens, Germany) following standard protocol. For contrast enhancement, non-ionic, iodinated, intravenous contrast material (Omnipaque 350 mg) was used. PE was detected by CTPA in 87(53.7%) COVID-19 patients. The D-dimer level was significantly higher in the PE group than in the non-PE group. The frequency of renal impairment in the PE group was 2.3 times higher than in the non-PE group. The ICU duration was longer in the PE group than in non-PE group (12.9±11.3 and 8.6±7.2 days, P=0.005). The death rate was 17.2% in the PE group and 1.3% in the non-PE group (P=0.001). The heart and respiratory rates, blood pressure, BMI, BUN, and creatinine levels did not differ in the study groups. The frequency of diabetes, hypertension, asthma, COPD, and smoking were comparable in the groups. Conclusion: CTPA is very important in diagnosing PE in COVID-19 patients. CTPA-diagnosed PE is significantly associated with D-dimer, ICU duration, and death.

Pulmonary Embolism Rule-out Criteria: Diagnostic Accuracy and Impact of COVID-19

BackgroundThe Pulmonary Embolism Rule-Out Criteria (PERC), developed to minimize unnecessary testing in low-risk pulmonary embolism (PE) cases, lacks clear validation in the context of COVID-19. ObjectivesTo assess the validity of the PERC in emergency department patients having undergone computed tomography pulmonary angiography (CTPA) during the COVID-19 pandemic. MethodsWe conducted a retrospective analysis of emergency department patients who underwent CTPA for suspected PE. COVID-19 status was based on the results of a reverse transcription-polymerase chain reaction (RT-PCR) test performed in the emergency department, or within 30 days prior to visiting the emergency department. We collected data on demographics, symptoms, d-dimer levels, and medical history relevant to thrombosis and conducted the PERC test using the criteria including age, oxygen saturation, heart rate, and the absence of hemoptysis or recent trauma. We categorized outcomes based on the concordance between the PERC results and CTPA findings, with specific definitions for true positive and negative, as well as false positive and negative results. We also evaluated the impact of COVID-19 status on the diagnostic performance of the PERC by analyzing the prevalence of PE in patients testing positive and negative for COVID-19. ResultsAmong the 2.430 participants, 45.1% tested negative for COVID-19, 43.4% tested positive, and 11.5% were untested. The PERC identified 91.2% of the cases as positive, 6.9% of which were confirmed to have PE. Overall, 84.9% of cases (n = 2.062) showed a discordant result between the PERC and CTPA findings. The lack of significant correspondence between the PERC positivity and actual PE presence (p = 0.001; p < 0.01) indicated low diagnostic concordance. In patients with a positive COVID-19 test result, the PERC demonstrated a sensitivity of 95.3% (95% CI: 86.91–99.02), a specificity of 9.1% (95% CI: 7.46–11.15), a positive predictive value of 6.3% (95% CI: 6.01–6.70), a negative predictive value of 96.8% (95% CI: 90.81–98.94), and an accuracy of 14.4% (95% CI: 12.34–16.67). In patients who tested negative for COVID-19, the sensitivity was 95.4% (95% CI: 88.64–98.73), the specificity was 7.8% (95% CI: 6.25–9.66), the positive predictive value was 8.1% (95% CI: 7.83–8.57), the negative predictive value was 95.1% (95% CI: 88.11–98.14), and the accuracy was 14.7% (95% CI: 12.73–17.02). ConclusionThe study demonstrates that the sensitivity and negative predictive value of the PERC are comparable in COVID-19 positive and negative patients. Furthermore, the incidence of PE among patients presenting to the emergency department did not significantly differ based on COVID-19 status. While this study highlights the relevance of the PERC in clinical decision-making, caution is advised as the PERC may not always provide reliable results when used as the sole diagnostic test.