Computed Tomography Pulmonary Angiography Research Articles

A study of modified Wells score for pulmonary embolism and age-adjusted D-dimer values in patients at risk for deep venous thrombosis.

Pulmonary embolism (PE) is the most severe complication of deep venous thrombosis (DVT). This study was designed to evaluate the usefulness of modified Wells score combined with age-adjusted D-dimer cut-off levels as a clinical pre-test probability assessment for predicting PE in patients 'at risk for DVT.' This was a cross-sectional study including 200 in-patients at risk for DVT. Patients were categorized as 'pulmonary embolism unlikely' or 'pulmonary embolism likely' using modified Wells score and underwent D-dimer testing. PE was considered excluded in patients classified as unlikely with normal D-dimer levels, whereas the rest of the patients underwent computed tomography pulmonary angiogram (CTPA). Out of 200 patients, 163 patients (81.50%) were 'pulmonary embolism unlikely,' whereas 37 patients (18.50%) were 'pulmonary embolism likely.' Of 163 patients categorized as 'pulmonary embolism unlikely,' 67 patients (41.5%) had normal D-dimer values and were excluded from CTPA. PE was detected in 24.2% of the patients who underwent CTPA. The combined strategy using modified Wells score and age-adjusted D-dimer cut-off value has 100% sensitivity and a negative predictive value and can be used to safely exclude PE in in-patients.

RELATIONSHIP BETWEEN BLOOD PRESSURE INDEX AND RIGHT VENTRICULAR DYSFUNCTION AND MORTALITY IN PATIENTS WITH PULMONARY EMBOLISM

Objective: Pulmonary embolism is a cardiopulmonary emergency commonly encountered in emergency departments with a high mortality rate. In cases of pulmonary embolism, the prompt and effortless implementation of echocardiography in the emergency department for the identification of right ventricular dysfunction, a significant predictor of mortality, is not always feasible. The aim of this study is to demonstrate the role of the readily available blood pressure index in determining right ventricular dysfunction and mortality in patients with pulmonary embolism.
 
 Material and Methods: A total of 180 patients (90 females and 90 males) who were diagnosed with pulmonary embolism based on computed tomography pulmonary angiography in the emergency department between 2013 and 2019 and subsequently underwent echocardiography were included in the study. The blood pressure index was obtained by dividing the systolic blood pressure by the diastolic blood pressure.
 
 Results: The average blood pressure index of the patients was calculated as 1.7±0.2. There was no statistically significant difference in terms of BPI between the two groups, one with right ventricular dysfunction and the other without right ventricular dysfunction, based on echocardiography (p=0.529). A total of 22.2% of the patients experienced 30-day mortality. There was no significant difference in terms of blood pressure index between the group with observed mortality and the group without observed mortality (p=0.438).
 
 Conclusion: No significant relationship was identified between blood pressure index and right ventricular dysfunction or mortality in patients with pulmonary embolism. However, considering the ease of accessibility and applicability of blood pressure index in emergency departments, we believe it can be considered as a useful parameter. We anticipate that blood pressure index would yield more accurate results in determining right ventricular dysfunction and mortality, especially in patients with pulmonary embolism who have reduced systolic blood pressure.

RV size may predict death in unstable patients with PE.

Pulmonary emboli (PE) is a life threatening condition that discovered in many patients only "post mortem". Sub massive and massive PE that led to hemodynamic collapse characterized by right ventricular (RV) dysfunction, leading to a higher risk of death. To assess the ability to predict in hospital death of patients with acute PE, using a non-gated computed tomography pulmonary angiography (CTPA), based on the dimensions of the right ventricle. A retrospective study that analyzed CTPA images of patients admitted with acute PE during the years 2012-2017. The cohort study included 300 patients with documented acute PE, among them 255 hospitalized in medical (non-intensive care unit) wards, 45 were hospitalized in an intensive care unit (ICU). Among the 45 patients admitted to the ICU 8% died. Larger RV diameters predicted mortality (OR = 10.14, 95% CI [1.09-93.86]) as well as lower systolic and diastolic blood pressure measurements (p = 0.001 and 0.01). Among the 255 patients admitted to the Internal Medicine Ward 7% died. Older age (p = 0.028), sepsis and cancer (both p < 0.001), high WBCs count (p < 0.001), and renal failure (p < 0.001) predicted death. Lower blood pressure (systolic and diastolic) (p < 0.001, 0.008), older age (p < 0.007), sepsis (p < 0.001), cancer (p = 0.006), higher WBCs count (p < 0.001), and impaired renal function (p < 0.001) predicted death in patients admitted with acute PE. Clinical parameters and hematological parameters could predict death of patients admitted with acute PE. RV diameter, measured by the non-ECG gated CTPA, had an additive predictive value for patients who admitted to the ICU.

Predicting acute pulmonary embolism in COVID-19.

Acute pulmonary embolism (PE) is a life-threatening condition in patients with Coronavirus disease-2019 (COVID-19). Computed tomography pulmonary angiography is the preferred test to confirm the diagnosis. However, computed tomography pulmonary angiography is expensive and is not available in every clinic. This study aimed to determine whether clinical findings, symptoms, and parameters that are cost-effective and available in many clinics such as C-reactive protein (CRP) lymphocyte ratio (CLR), and ferritin CRP ratio (FCR) can be used in the diagnosis of PE in patients with COVID-19. Out of the reviewed files, 127 patients were diagnosed with PE, whereas 105 patients had no PE. At the first admission, laboratory parameters, complaints, respiratory rate, and percent oxygen saturation in the blood (SpO2) with a pulse oximeter were recorded for each patient. Eosinophil levels remained lower, whereas ferritin lymphocyte ratio and CLR were higher in the PE group. Patients with more elevated ferritin, CRP, and CLR had an increased mortality risk. Shortness of breath and tiredness was more common in the PE group. A decrease in eosinophil levels, whereas an increase in CLR, D-dimer, and CRP may predict PE. Elevated CLR is highly predictive of PE and is associated with increased mortality risk. COVID-19 patients with a CLR level above 81 should be investigated for PE.

Prevalence of Pulmonary Embolism among COVID-19 Patients Using Multidetector Computed Tomography

Background Thrombotic complications in patients diagnosed with (COVID-19) are emerging as an important sequela that contribute to significant morbidity and mortality Aim of the Work To discuss prevalence of pulmonary embolism as one of the thrombotic complications in COVID-19 Egyptian population. Patients and Methods Our study is a retrospective study that included patients from period August 2020 to July 2021. The study included 50 patients who were diagnosed as having COVID19 infection, referred to the Radiology department, Ain Shams University Hospitals for a CT pulmonary angiography due to clinical suspicion of acute pulmonary embolism PE. Results Acute pulmonary embolism was found in 22% of patient diagnosed with COVID-19 who underwent CT pulmonary angiography. 81.8% of patients with acute PE were males. The most common distribution site for embolism was in segmental branches (81.8%). 100 % of patients with acute PE had high D-dimer levels, while only 50% pf patients with no PE had elevated D-dimer levels. Conclusion Pulmonary embolism is a relatively common complication during COVID-19 pandemic, and it is associated with high D-dimer levels. This is one of the thrombotic complications of this disease which needs early recognition and management.

Semi-automatic quantification of mosaic perfusion of lung parenchyma and its correlation with haemodynamic parameters in patients with chronic thromboembolic pulmonary hypertension

To investigate the feasibility of semiautomatic quantification of mosaic perfusion and the associations between mosaic perfusion on computed tomography (CT; the ratio of hypoperfused parenchyma to the whole lung volume) and haemodynamic parameters through linear regression analysis. Fifty-eight consecutive patients (mean age 66 years, 28 females) diagnosed with chronic thromboembolic pulmonary hypertension (CTEPH) in General University Hospital, Prague, in 2021 were evaluated retrospectively and underwent both right heart catheterisation and CT pulmonary angiography. The parameters derived from the CT examinations were correlated with the recorded haemodynamic parameters. A method was developed for semiautomatic detection of hypoperfused tissue from CT using widely available software and a statistically significant correlation was found between the proportion of hypoperfused parenchyma and the mean pulmonary artery pressure (mPAP; R2 0.22; p<0.01) and pulmonary vascular resistance (PVR; R2 0.09; p<0.05). The developed method facilitates the quantification of mosaic perfusion, which is associated with important haemodynamic parameters (mPAP and PVR) in patients with CTEPH.

Even non-expert radiologists report chronic thromboembolic pulmonary hypertension (CTEPH) on CT pulmonary angiography with high sensitivity and almost perfect agreement.

To assess the diagnostic performance and interobserver agreement of CT pulmonary angiography (CTPA) in the detection of chronic thromboembolic pulmonary hypertension (CTEPH) and its features among radiologists of different levels of experience. In this retrospective, single-center, single-blinded study, three radiologists with different levels of experience in CT imaging (R1:15 years, R2:6 years, and R3:3 years) evaluated CTPA of 51 patients ultimately diagnosed with CTEPH (European Society of Cardiology guidelines) and 49patients without CTEPH in random order to assess the presence of CTEPH, its features in the pulmonary artery tree, proximal level of involvement, bronchial artery hypertrophy, mosaic perfusion, and right heart overload. CTPAs of 51 patients with CTEPH (median age, 66 years (IQR 56-72), 28 men) and 49 patients without CTEPH (median age, 65 years (IQR 50-74), 25 men) were evaluated. The sensitivity and specificity for the detection of CTEPH was 100% (all radiologists) and 100% (R1), 96% (R2), and 96%(R3) with almost perfect agreement (κ = 0.95). The sensitivity and specificity for detecting CTEPH by mosaic perfusion would be 89% (95%CI 83-93%) and 81% (74-87%). The level of pulmonary artery involvement was reported with moderate agreement (κ = 0.54, 95%CI 0.40-0.65). Substantial agreement was found in the evaluation of mosaic attenuation (κ = 0.75, 95%CI 0.64-0.84), right heart overload (κ = 0.68, 95%CI 0.56-0.79), and bronchial artery hypertrophy (0.71, 95%CI 0.59-0.82) which were the best predictors of CTEPH (p < 0.0001). CTPA has high sensitivity and specificity in detecting CTEPH and almost perfect agreement among radiologists of different levels of expertise. CT pulmonary angiography can be used as a first-line imaging modality in patients with suspected chronic thromboembolic pulmonary hypertension (CTEPH) even when interpreted by non-CTEPH experts. • CT pulmonary angiography has high sensitivity and specificity in detecting chronic thromboembolic pulmonary hypertension (CTEPH) and almost perfect interobserver agreement among radiologists of different levels of expertise. • Substantial agreement exists in the assessment of mosaic attenuation, right heart overload, and bronchial artery hypertrophy, which are the best predictors of CTEPH.

CT-derived lung vessel morphology correlates with prognostic markers in precapillary pulmonary hypertension

While computed tomography pulmonary angiography (CTPA) is an integral part of the work-up in patients with suspected pulmonary hypertension (PH), there is no established CTPA-derived prognostic marker. We aimed to assess whether quantitative readouts of lung vessel morphology correlate with established prognostic indicators in PH. We applied a fully-automatic in-house developed algorithm for segmentation of arteries and veins to determine lung vessel morphology in patients with precapillary PH who underwent right heart catheterization and CTPA between May 2016 and May 2019. Primary endpoint of this retrospective study was the calculation of receiver operating characteristics for identifying low and high mortality risk according to the 3-strata risk assessment model presented in the current guidelines. We analyzed 73 patients, median age 65years (interquartile range (IQR): 54-76), female/male ratio 35/38, median mean pulmonary arterial pressure 37mm Hg (IQR: 30-46), and found significant correlations with important prognostic factors in pulmonary arterial hypertension. N-terminal pro-brain natriuretic peptide, cardiac index, mixed venous oxygen saturation, and 6-minute walking distance were correlated with the ratio of the number of arteries over veins with vessel diameters of 6-10mm (Spearman correlation coefficients ρ=0.64, p<0.001; ρ=-0.60, p<0.001; ρ=-0.47, p=0.005; ρ=-0.45, p=0.001, respectively). This ratio predicted a low- and high-risk score with an area under the curve of 0.73 (95% confidence interval (CI): 0.56-0.90) and 0.86 (95% CI: 0.74-0.97), respectively. The ratio of the number of arteries over veins with diameters between 6 and 10mm is significantly correlated with prognostic markers in pulmonary hypertension and predicts low and high mortality risk.

Clot Burden As a Predictor of Chronic Thromboembolic Pulmonary Hypertension After Acute Pulmonary Embolism: A Cohort Study.

A small percentage of acute pulmonary thromboembolisms (PTE) persist as chronic fibrin clots, potentially leading to chronic thromboembolic pulmonary hypertension (CTEPH). A scoring system for evaluating the burden of acute PTE based on computed tomography pulmonary angiogram (CTPA) findings was tested for its association with CTEPH within one year. In this retrospective cohort of 475 patients with a definitive diagnosis of acute PTE, the Qanadli score (QS) was calculated on the initial CTPA. Through regular follow-up over 1 year, symptomatic patients underwent extensive evaluation. Of the 475 patients enrolled in the study [age 58.3 ± 16.6, 195 (41.1%) female, QS: 13.01 ± 7.37/40], 321 patients completed the study. A total of 22 (6.8%) patients were definitively diagnosed with CTEPH. In univariate analysis, the initial QS was significantly higher in patients with subsequent CTEPH than in patients without (17 ± 5.6 vs. 13 ± 7.6, P = .009). QS was directly associated with CTEPH (odds ratio: 1.08, 95% confidence interval: 1.0-1.16, P = .042). The evolution of CTEPH in men could be predicted with a sensitivity of 100% and a specificity of 54% when a cut-off point of 14.5 (43.5%) was set for QS. The area under the receiver operating characteristic curve in this setting was 0.74 with a P-value of .032. Qanadli score failed to predict CTEPH in women. Scoring the clot burden in the pulmonary arteries through the Qanadli method can predict the evolution of CTEPH only in men 1 year after acute PTE. Women comprise most of the CTEPH patients. Thus, strict follow-up adherence seems to be even more important in women.

Nomogram for predicting pulmonary embolism in gynecologic inpatients with isolated distal deep venous thrombosis.

To investigate the incidence of isolated distal deep venous thrombosis (IDDVT) concurrent with pulmonary embolism (PE) in gynecologic inpatients, analyze the risk factors for IDDVT with PE, and establish a nomogram model for IDDVT patients with PE. A total of 260 patients were diagnosed with IDDVT between December 2017 and November 2020. The incidence of PE in these patients was determined using computed tomography pulmonary angiography. Logistic regression analysis was used to identify the related risk factors. On this basis, nomogram risk prediction models were established. Among 260 patients with IDDVT, 106 (40.8%) had concurrent PE, of whom 74 (28.5%) experienced silent PE. Univariate logistic analysis demonstrated statistical significance for body mass index (BMI; P = 0.044), glucocorticoid therapy (P = 0.009), hypertension (P < 0.001), and diabetes (P < 0.001). Multivariate logistic analysis revealed that these were independent risk factors for IDDVT with PE that retained statistical significance. A nomogram based on these factors was constructed to predict PE in patients with IDDVT. Its receiver operating characteristic (ROC) showed an area under the curve of 0.710 (95% confidence interval 0.642-0.779), with prediction sensitivity of 64.2% and prediction specificity of 76.6%. In the present study, a high prevalence of PE was found in gynecologic inpatients with IDDVT. Glucocorticoid therapy, hypertension, diabetes, and BMI were independent risk factors for IDDVT patients with PE. Taking these risk factors into account, a nomogram risk prediction model was developed to help facilitate early detection of concurrent PE.

Detection of Low Blood Hemoglobin Levels on Pulmonary CT Angiography: A Feasibility Study Combining Dual-Energy CT and Machine Learning.

To evaluate if dual-energy CT (DECT) pulmonary angiography (CTPA) can detect anemia with the aid of machine learning. Inclusion of 100 patients (mean age ± SD, 51.3 ± 14.8 years; male-to-female ratio, 42/58) who underwent DECT CTPA and hemoglobin (Hb) analysis within 24 h, including 50 cases with Hb below and 50 controls with Hb ≥ 12 g/dL. Blood pool attenuation was assessed on virtual noncontrast (VNC) images at eight locations. A classification model using extreme gradient-boosted trees was developed on a training set (n = 76) for differentiating cases from controls. The best model was evaluated in a separate test set (n = 24). Blood pool attenuation was significantly lower in cases than controls (p-values < 0.01), except in the right atrium (p = 0.06). The machine learning model had sensitivity, specificity, and accuracy of 83%, 92%, and 88%, respectively. Measurements at the descending aorta had the highest relative importance among all features; a threshold of 43 HU yielded sensitivity, specificity, and accuracy of 68%, 76%, and 72%, respectively. VNC imaging and machine learning shows good diagnostic performance for detecting anemia on DECT CTPA.

Comparison of pulmonary vascular tortuosity and fractal dimension in patients with chronic thromboembolic pulmonary disease and chronic thromboembolic pulmonary hypertension

Objective: To compare the differences in pulmonary vascular morphological parameters between patients with chronic thromboembolic pulmonary disease (CTEPD) and chronic thromboembolic pulmonary hypertension(CTEPH), and to explore the value of pulmonary artery morphology in the differential diagnosis of CTEPD and CTEPH. Methods: Thirty-nine patients with CTEPH [14 males, 25 females, mean age: (54.1±12.4) years] and 29 patients with CTEPD [10 males, 19 females, mean age: (51.4±18.0) years] from January 2018 to December 2020 were retrospectively included. The pulmonary artery and vein tree was segmented from the computed tomography pulmonary angiography (CTPA) images, and the morphological parameters of pulmonary vessels including the number of pulmonary arteries, pulmonary arterial tortuosity(distance metric, DM) and fractal dimension (FD), were calculated. The differences in pulmonary vascular morphological parameters between the two groups were compared, and the correlation between morphological parameters and hemodynamics was analyzed. Results: There was no significant difference in gender and age between CTEPH and CTEPD groups (χ2=0.015,P=0.904 & t=-0.729, P=0.469). The number of pulmonary arteries in CTEPH group (n=249.43±76.27) was significantly lower than that in CTEPF group (n=298.79±78.11, t=2.612, P=0.011). The pulmonary arterial tortuosity in CTEPH group (DM=1.26±0.17) was significantly higher than that in CTEPD group (DM=1.17±0.10, t=3.516, P=0.002). There was no significant difference in FD between CTEPH and CTEPD (FD=3.01±0.21 & 3.08±0.22, t=1.359, P=0.179). The number of pulmonary arteries was negatively correlated with pulmonary vascular resistance (r=-0.325, P=0.026). Pulmonary arterial tortuosity was positively correlated with mean pulmonary artery pressure (r=0.387,P=0.017), and was positively correlated with pulmonary vascular resistance (r=0.647, P<0.001). Conclusion: Pulmonary artery curvature is an important morphological parameter in differentiating CTEPH from CTEPD, and is related to mean pulmonary artery pressure and pulmonary vascular resistance.

Role of MRI in diagnosis of pulmonary embolism

BackgroundPulmonary embolism (PE) is considered a serious condition and has clinical challenges in diagnosis. Computed tomography pulmonary angiography (CTPA) is considered the gold standard in PE diagnosis. Contrast-enhanced MRA also has a strong useful role in the diagnosis. Our study aims to assess the role of non-contrast MRA in diagnosis of acute pulmonary embolism compared to either CT pulmonary angiography or contrast enhanced MRA.ResultsIn total, 50 patients with PE confirmed by either CTPA or CE-MRA were included in this study. All patients underwent non-contrast MRPA during the three consecutive days after CTPA or at the same examination setting in CE-MRA. The results were compared and statistically analyzed.The mean age of our study group was 47.80 ± 14.01 years. Males represented 56% (28/50) and females 44% (22/50). The per-vessel sensitivity, specificity and accuracy of non-contrast MRPA reached about 100% for each parameter at the level of the pulmonary trunk, main pulmonary and lobar arteries. At the segmental level, sensitivity, specificity, and accuracy reached about 88%, 100%, and 94%, while at the subsegmental level, about 35%, 100%, and 66% respectively. The overall sensitivity, specificity, and accuracy of non-contrast MRPA regardless of the site were 84%, 100%, and 90% respectively.ConclusionsNon-contrast pulmonary MRA has a high sensitivity and specificity in the diagnosis of PE, especially in proximal pulmonary arteries. So, it can be used as an alternative to the CTA and CE-MRA, especially when the CTA and the use of gadolinium are contraindicated.

Delayed pulmonary embolism occurring six months after a mild COVID infection: A case report

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a globally impactful disease. Venous Thromboembolism (VTE), particularly pulmonary embolism is common in the acute stages. Occurrence after initial recovery remains rare. We report a 43-year-old man who was admitted following acute onset shortness of breath six months after mild SARS-CoV-2 infection. Computed Tomography Pulmonary Angiogram revealed a bilateral pulmonary embolism. No other risk factors for VTE were identified. This case report raises concern over a persistent pro-coagulopathy state caused by the SARS-Cov-2 virus even after recovering from the initial infection.

Predictive value of reduced pulmonary arterial elasticity in acute pulmonary embolism for right ventricular dysfunction.

Computed tomography pulmonary angiography (CTPA) yields indices, such as the right ventricular/left ventricular (RV/LV) ratio > 1.0, which are commonly used for risk stratification of patients with acute pulmonary embolism (APE). Although pulmonary artery elasticity (PAE) has been previously described, its relationship with right ventricular dysfunction (RVD) has not been explored. Here, we investigated whether PAE, measured using CTPA, is associated with RVD. Patients who underwent retrospective electrocardiogram-gated CTPA and had a definitive diagnosis of APE were included in the study. The subjects were classified into RVD and non-RVD groups according to the RVD on echocardiography. PAE, involving aortic distensibility (AD), aortic compliance (AC), and aortic stiffness (ASI), and right heart function indices were compared between the two groups, and their correlations were examined. Receiver operating characteristic (ROC) curves were generated to evaluate the specificity and sensitivity of the RVD prediction. Thirty-five patients with APE were enrolled in the study (RVD: 18, non-RVD: 17). The groups showed no significant differences in age, sex, number of patients receiving thrombolysis, and number of high-risk conditions (P > 0.05). Regarding PAE parameters, AD was significantly reduced in the RVD group compared to that in the non-RVD group (P < 0.05), whereas AC and ASI were not statistically different (P > 0.05). The ratio of the maximum cross-sectional area of PA and AA (PA/AAmax),the ratio of the minimum cross-sectional area of PA and AA(PA/AAmin), diameter of the coronary sinus, RV/LV diameter, RV/Lvarea, the ratio of the end-diastolic volume of right ventricular and left ventricular (RV/LVDV), the ratio of the end-systolic volume of right ventricular and left ventricular (RV/LVSV) were significantly greater in the RVD group than in the non-RVD group (P < 0.05). Correlation analysis of AD and right heart function parameters showed that AD was negatively correlated with PA/AAmax, PA/AAmin, RV/LV diameter, RV/LVDV, and PAE measured by ultrasound, with correlation coefficients ranging from - 0.336 to - 0.580 (P < 0.05). The ROC curves of AD and RV/LVdiameter to predict RVD had areas under the curve of 0.748 and 0.712, sensitivities of 82.35% and 70.59%, specificities of 66.67% and 72.22%, and cutoff values of 4.9433 and 1.1105, respectively. AD obtained by retrospective ECG-gated CTPA may be helpful in assessing RVD in patients with APE while accurately diagnosing APE. It contributes to timely diagnosis and treatment and improves the prognosis of patients with APE.

Validation of clinical-radiological scores for prognosis of mortality in acute pulmonary embolism

IntroductionAcute pulmonary embolism (APE) is a hazardous disorder with a high mortality. Combination of clinical, radiological, and serological parameters can improve risk stratification of APE. Most of the proposed combined scores were not validated in independent cohorts. Our aim was to validate the proposed clinical-radiological scores for prognosis of 7- and 30-day mortality in APE.Materials and methodsOur sample comprised 531 patients with APE, mean age 64.8 ± 15.6 years, 221 (41.6%) females and 310 (58.4%) males. The following parameters were collected: Age and sex of the patients, mortality within the observation time of 30 days, simplified pulmonary embolism severity index (sPESI), pH troponin level (pg/ml), minimal systolic and diastolic blood pressures (mmHg), heart rate, O2 saturation, episodes of syncope, and need for vasopressors. On CT pulmonary angiography (CTPA), short axis ratio right ventricle/left ventricle (RV/LV), and reflux of contrast medium into the inferior vena cava were obtained. The following clinical-radiological scores were calculated: BOVA score, pulmonary embolism mortality score (PEMS), European Society of Cardiology (ESC) score, Kumamaru score, and Calgary acute pulmonary embolism (CAPE) score.ResultsOverall, 31 patients (5.8%) died within seven and 64 patients (12%) within 30 days. All scores showed high negative prognostic values ranging from 89.0 to 99.0%. PEMS and CAPE score demonstrated the highest specificity for 7-day mortality (93.4% and 85.0%), PEMS and BOVA for 30-day mortality (94.2% and 90.4%). The highest sensitivity was observed for ESC 2019 (96.8% and 95.3%). Kumamaru and CAPE scores had low sensitivity. All scores had low positive and high negative predictive values.ConclusionFor prognosis of 7- and 30-day mortality in APE, PEMS score has the highest specificity. ESC 2019 shows the highest sensitivity. All scores had low positive and high negative predictive values.

Pixel-level annotated dataset of computed tomography angiography images of acute pulmonary embolism

Pulmonary embolism has a high incidence and mortality, especially if undiagnosed. The examination of choice for diagnosing the disease is computed tomography pulmonary angiography. As many factors can lead to misinterpretations and diagnostic errors, different groups are utilizing deep learning methods to help improve this process. The diagnostic accuracy of these methods tends to increase by augmenting the training dataset. Deep learning methods can potentially benefit from the use of images acquired with devices from different vendors. To the best of our knowledge, we have developed the first public dataset annotated at the pixel and image levels and the first pixel-level annotated dataset to contain examinations performed with equipment from Toshiba and GE. This dataset includes 40 examinations, half performed with each piece of equipment, representing samples from two medical services. We also included measurements related to the cardiac and circulatory consequences of pulmonary embolism. We encourage the use of this dataset to develop, evaluate and compare the performance of new AI algorithms designed to diagnose PE.

Clinicians' interpretation of ventilation/perfusion lung scan reports: Where are we today?

Clinicians' interpretation of lung scan reports will determine which further management decisions are taken when potentially fatal pulmonary embolism (PE) is suspected. To assess current referring clinicians' interpretation of the terminology used in ventilation/perfusion (V/Q) scan reports, whether this interpretation is affected by experience level, and how it affects clinical management decisions. This was a questionnaire-based cross-sectional study. Between September 2020 and May 2021, 300 questionnaires were distributed among clinicians who refer patients for V/Q scans. Of the 162 clinicians who responded, 94% thought that there is >85% likelihood of PE or definitely PE present when a scan is reported as 'high probability of PE'; 87% interpreted 'low probability of PE' as <10% likelihood of PE or definitely no PE present. Overall, >70% of clinicians across all experience levels correctly interpreted the intended meaning of probability categories according to the Modified Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II criteria. Of the respondents, 77% agreed that clinically significant PE is ruled out by a normal scan. Further investigation for inconclusive findings, features of parenchymal lung disease and cardiomegaly were selected by 72%, 93% and 98% of clinicians, respectively. The findings of this study regarding high-probability scan results were in line with existing literature on lung scan report interpretation. However, our findings regarding low-probability scan results and negative V/Q scan specificity contrasted with the findings in these articles, suggesting that clinicians are now more familiar with lung scan interpretation guidelines. Experience level did not significantly affect interpretation of reports. Although most clinicians agreed that a negative scan excludes clinically significant PE, two-thirds of them would still subject the patient to further unnecessary investigations to exclude PE. What the study adds. Our findings regarding a low-probability ventilation/perfusion (V/Q) scan and the specificity of a negative V/Q scan contrasted with previous articles on lung scan interpretation, suggesting that clinicians are now more familiar with lung scan interpretation guidelines.Implications of the findings. Although most clinicians understood the negative predictive value of a V/Q scan, 20% would still investigate further with computed tomography pulmonary angiography or treat as confirmed pulmonary embolism. Education of clinicians about the negative predictive value of V/Q scans is important to avoid unnecessary radiation or anticoagulation.

Prevalence of long-term right ventricular dysfunction after acute pulmonary embolism: a systematic review and meta-analysis

Right ventricular dysfunction (RVD) is associated with adverse outcomes of acute pulmonary embolism (PE). However, there are no studies describing the long-term, full-spectrum right ventricular parameters on morphology, pressure and function at certain follow-up time points after PE onset. More exploration of right ventricular function would provide useful clues for long-term management of patients with PE. For this systematic review and meta-analysis, we completed a literature search in Pubmed, EMBASE and WebofScience (from Jan 1st, 1998 to April 20th, 2023). Studies of patients with acute PE followed-up longer than 3 months with right ventricle assessment and written in English-language were included. Right ventricular function was assessed by either echocardiography or computed tomographic pulmonary angiography (CTPA). The primary outcome was structural and functional parameters of the right ventricle, and the secondary outcomes were functional assessments [New York Heart Association (NYHA) functional classification and 6-min walk test distance (6MWD)], at each follow-up time points. Random effect meta-analyses were performed using R software (PROSPERO: CRD42023433332). A total of 33 studies (3920 patients) were included in the final analysis. The 3-month, 6-month and 1-year prevalence of right ventricular dysfunction (RVD) was 0.34 [95% confidence interval (CI) 0.21-0.48, I2=96%], 0.26 (95% CI 0.17-0.36, I2=93%) and 0.34 (95% CI 0.19-0.48, I2=94%), respectively. Pooled tricuspid annulus plane systolic excursion (TAPSE), right ventricular to left ventricular diameter (RV/LV) ratio and pulmonary artery systolic pressure (PASP) at 1-year was 21.80mm (95% CI 20.08-23.52, I2=93%), 0.64 (95% CI 0.48-0.81, I2=92%) and 27.33mmHg (95% CI 18.88-35.78) (I2=96%), respectively. The proportion of NYHA III-IV was 0.06 (95% CI 0.0-0.12) and the pooled 6MWD was 462.98m (95% CI 447.55-478.41) over 1 year. Patients treated with thrombolysis had lower prevalence of RVD (1-year 0.17 and 0.07 in systemic thrombolysis and catheter-directed thrombolysis, respectively) than those treated with anticoagulation therapy alone (1-year 0.24) but the pooled risk ratio (RR) was not statistically significant. Although the conclusion of this study may be limited by its high heterogeneity from varied study designs, inclusion criteria and definition of RVD of each study, our findings suggested that persistent RVD and functional impairment were of considerable high prevalence during long-term follow-up after acute PE. Treatment strategy may influence the prevalence of long-term RVD. This study is supported by CAMS Innovation Fund for Medical Sciences (CIFMS) (2021-I2M-1-061). The National Key Research and Development Program of China (2016YFC0905600). National High Level Hospital Clinical Research Funding (2022-NHLHCRF-LX-01-02-03). CAMS Institute of Respiratory Medicine Grant for Young Scholars (2023-ZF-8).

Prognostic value of right ventricular dilatation on computed tomography pulmonary angiogram for predicting adverse clinical events in severe COVID-19 pneumonia.

Right ventricle dilatation (RVD) is a common complication of non-intubated COVID-19 pneumonia caused by pro-thrombotic pneumonitis, intra-pulmonary shunting, and pulmonary vascular dysfunction. In several pulmonary diseases, RVD is routinely measured on computed tomography pulmonary angiogram (CTPA) by the right ventricle-to-left ventricle (LV) diameter ratio > 1 for predicting adverse events. The aim of the study was to evaluate the association between RVD and the occurrence of adverse events in a cohort of critically ill non-intubated COVID-19 patients. Between February 2020 and February 2022, non-intubated patients admitted to the Amiens University Hospital intensive care unit for COVID-19 pneumonia with CTPA performed within 48 h of admission were included. RVD was defined by an RV/LV diameter ratio greater than one measured on CTPA. The primary outcome was the occurrence of an adverse event (renal replacement therapy, extracorporeal membrane oxygenation, 30-day mortality after ICU admission). Among 181 patients, 62% (n = 112/181) presented RVD. The RV/LV ratio was 1.10 [1.05-1.18] in the RVD group and 0.88 [0.84-0.96] in the non-RVD group (p = 0.001). Adverse clinical events were 30% and identical in the two groups (p = 0.73). In Receiving operative curves (ROC) analysis, the RV/LV ratio measurement failed to identify patients with adverse events. On multivariable Cox analysis, RVD was not associated with adverse events to the contrary to chest tomography severity score > 10 (hazards ratio = 1.70, 95% CI [1.03-2.94]; p = 0.04) and cardiovascular component (> 2) of the SOFA score (HR = 2.93, 95% CI [1.44-5.95], p = 0.003). Right ventricle (RV) dilatation assessed by RV/LV ratio was a common CTPA finding in non-intubated critical patients with COVID-19 pneumonia and was not associated with the occurrence of clinical adverse events.