Epidemiology of pulmonary embolism diagnosis and management among United States emergency departments over an eight-year period.

INTRODUCTION: Pulmonary embolism (PE) is a major cause of morbidity and mortality in the United States. However, as diagnostic imaging, risk stratification tools, and treatment have evolved over time, there is a critical need for current data on the incidence, testing, admission rates, and medical management of PE in the ED setting. METHODS: This was a cross-sectional study of ED patients with PE diagnoses from 1/1/2016 to 12/31/2023 using the Epic Cosmos national database. ED visits were identified using ICD-10 codes corresponding to acute PE. Chronic PEs were excluded. Outcomes included total ED visits, admission rates, anticoagulant treatment prescribed from the ED, and thrombolytic therapy. Anticoagulant prescriptions included warfarin, enoxaparin, dabigatran, apixaban, rivaroxaban, edoxaban, and betrixaban. Thrombolytic agents included alteplase, tenecteplase, and urokinase. We also assessed changes in the overall rate of CT pulmonary angiograms (CTPA) performed. RESULTS: Out of 186,138,130 total ED encounters, PE represented 531,968 (0.29 %). The overall rate of PE diagnosis rose slowly from 0.20 % in 2016 to a peak of 0.35 % in 2021. Among those with PE, 363,584 (68.3 %) were admitted. The rate of admission declined over time from 75.6 % to 66.1 %. Among those prescribed anticoagulation, the most common medication was apixaban (40.0 %), followed by rivaroxaban (17.3 %), enoxaparin (6.1 %), warfarin (2.6 %), and dabigatran (0.4 %). Thrombolytics were administered in 4.5 % of cases, with the rate of thrombolytics peaking at 5.3 % in 2018 before lowering to 3.5 % in 2023. The overall rate of CTPA increased from 2.4 % to 5.0 %, while the rate of proportion of PEs diagnosed declined from 8.7 % to 6.4 %. CONCLUSION: This study highlights significant shifts in the epidemiology and management of PE within the ED setting. Overall rates of PE rose, while a larger proportion were discharged. Direct oral anticoagulants have become the predominant therapy with the majority of patients receiving apixaban. Thrombolytic use occurs in a small subset and has been declining over time. CTPA rates have risen, while the overall diagnostic yield has declined.

Acute cor pulmonale following uterine artery embolization.

Uterine artery embolization (UAE) is a common procedure for controlling gynecological and obstetric bleeding. We report a case of a 38-year-old female with placenta increta who underwent UAE following a cesarean section and subsequently developed pulmonary embolism from nontarget embolization. Excellent CTPA images demonstrate embolization agents used in the procedure in the pulmonary vasculature. The patient developed acute cor pulmonale, an infrequent complication from the procedure. This case presents a rare and clear demonstration of a complication of uterine artery embolization with clear imaging evidence.

Establishing a risk prediction model for residual pulmonary vascular obstruction after regular anticoagulant therapy for non-high-risk pulmonary embolism.

Background: The incidence of pulmonary embolism (PE) has been on the rise annually. Despite receiving regular sequential anticoagulation therapy, some patients with non-high-risk acute PE (APE) continue to experience residual pulmonary vascular obstruction (RPVO). This study sought to identify the risk factors for RPVO following 3 months of sequential anticoagulation therapy for non-high-risk PE. Machine learning techniques were utilized to construct a clinical prediction model for predicting the occurrence of RPVO. Methods: A total of 254 acute non-high-risk PE patients were included in this study, all of whom were admitted to the Third People's Hospital of Yunnan Province between 2020 and 2023. After 3 months of regular anticoagulant treatment, computed tomography pulmonary angiography (CTPA) were reviewed to identify the presence of RPVO. Patients were then categorized into either the thrombolysis group or the thrombosis residue group. Throughout the study period, 49 patients were excluded due to missing data, irregular treatment, or loss to follow-up. Clinical symptoms, physical signs, and laboratory results of 205 PE patients were recorded. Correlation and collinearity analyses were conducted on relevant risk factors, and significance tests were performed. Heat maps illustrating the relationships between influencing factors were generated. Predictors were selected using least absolute shrinkage and selection operator (LASSO) regression, followed by multivariate logistic regression analysis to create a predictive model. Internal validation of the model was also carried out. Results: By searching the literature to understand all the clinical indicators that may affect the efficacy of anticoagulation therapy. A total of 205 patients with non-high-risk acute pulmonary thromboembolism were evaluated for various risk factors. Five independent factors were identified by multivariable analysis-age, chronic obstructive pulmonary disease (COPD), acratia, pulmonary systolic blood pressure (PASP), and major arterial embolism-and their P value, odds ratio (OR) and confidence interval (CI) were as follows: (P=0.012, OR =1.123; 95% CI: 1.026-1.23), (P=0.002, OR =13.30; 95% CI: 2.673-66.188), (P=0.001, OR =14.009; 95% CI: 2.782-70.547), (P=0.003, OR =1.061; 95% CI: 1.020-1.103) and (P<0.001, OR =18.128; 95% CI: 3.853-85.293), which may indicate a poor prognosis after standard anticoagulant therapy. A nomogram was constructed using these variables and internally validated. The receiver operating characteristic (ROC) curves of the model demonstrated strong predictive accuracy, with an area under the curve (AUC) of 0.94 (95% CI: 0.89-0.96) for the training set and 0.93 (95% CI: 0.88-0.95) for the validation set. Calibration curves were utilized to assess the practicality of the nomogram. Conclusions: A novel predictive model was developed based on a single-center retrospective study to identify patients with RPVO following anticoagulant therapy for acute non-high-risk PE. This model may aid in the early detection of patients, prompt adjustment of treatment, and ultimately lead to a decrease in adverse outcomes.

Pulmonary Embolism With Syncope Treated With Inari FlowTriever®.

Pulmonary embolism (PE) is a devastating disease that can range in severity from asymptomatic to fatal. The severity and the intervention required depend on the degree of hemodynamic instability and evidence of right heart strain demonstrated on diagnostic testing. Interventions include solely anticoagulation, systemic thrombolysis, catheter-directed therapies, or surgical embolectomy depending on the severity, patient's clinical picture, and clinician choice. Currently, there is a lack of evidence regarding which treatment is most suitable for submassive PE. This report demonstrates the benefits of aspiration thrombectomy, a catheter-directed therapy, utilizing the 24Fr Triever Aspiration Catheter (FlowTriever® system;Inari Medical, Irvine, California, United States) in a 57-year-old male patient with submassive PE. The FlowTriever retrieval/aspiration system is a single-use mechanical thrombectomy device indicated for use in the peripheral vasculature and pulmonary arteries. The patient presented with syncope and concern for head trauma ultimately requiring suction embolectomy utilizing the Inari FlowTriever system. We conclude that submassive PE can be effectively treated with aspiration thrombectomy in addition to long-term anticoagulation with excellent clinical outcomes.

An Enhanced Mask R-CNN Approach for Pulmonary Embolism Detection and Segmentation.

Pulmonary embolism (PE) refers to the occlusion of pulmonary arteries by blood clots, posing a mortality risk of approximately 30%. The detection of pulmonary embolism within segmental arteries presents greater challenges compared with larger arteries and is frequently overlooked. In this study, we developed a computational method to automatically identify pulmonary embolism within segmental arteries using computed tomography (CT) images. The system architecture incorporates an enhanced Mask R-CNN deep neural network trained on PE-containing images. This network accurately localizes pulmonary embolisms in CT images and effectively delineates their boundaries. This study involved creating a local data set and evaluating the model predictions against pulmonary embolisms manually identified by expert radiologists. The sensitivity, specificity, accuracy, Dice coefficient, and Jaccard index values were obtained as 96.2%, 93.4%, 96.%, 0.95, and 0.89, respectively. The enhanced Mask R-CNN model outperformed the traditional Mask R-CNN and U-Net models. This study underscores the influence of Mask R-CNN's loss function on model performance, providing a basis for the potential improvement of Mask R-CNN models for object detection and segmentation tasks in CT images.

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.

Pulmonary embolism versus pulmonary vasculitis in Hughes-Stovin syndrome: Characteristic computed tomography pulmonary angiographic findings and diagnostic and therapeutic implications. HSS International Study Group.

BACKGROUND AND AIM: Hughes-Stovin syndrome (HSS) is a rare systemic vasculitis with widespread venous/arterial thrombosis and pulmonary vasculitis. Distinguishing between pulmonary embolism (PE) and in-situ thrombosis in the early stages of HSS is challenging. The aim of the study is to compare clinical, laboratory, and computed tomography pulmonary angiography (CTPA) characteristics in patients diagnosed with PE versus those with HSS. METHODS: This retrospective study included 40 HSS patients with complete CTPA studies available, previously published by the HSS study group, and 50 patients diagnosed with PE from a single center. Demographics, clinical and laboratory findings, vascular thrombotic events, were compared between both groups. The CTPA findings were reviewed, with emphasis on the distribution, adherence to the mural wall, pulmonary infarction, ground glass opacification, and intra-alveolar hemorrhage. Pulmonary artery aneurysms (PAAs) in HSS were assessed and classified. RESULTS: The mean age of HSS patients was 35 ± 12.3 years, in PE 58.4 ± 17 (p < 0.0001). Among PE 39(78 %) had co-morbidities, among HSS none. In contrast to PE, in HSS both major venous and arterial thrombotic events are seen.. Various patterns of PAAs were observed in the HSS group, which were entirely absent in PE. Parenchymal hemorrhage was also more frequent in HSS compared to PE (P < 0.001). CONCLUSION: Major vascular thrombosis with arterial aneurysms formation are characteristic of HSS. PE typically appear loosely-adherent and mobile whereas "in-situ thrombosis" seen in HSS is tightly-adherent to the mural wall. Mural wall enhancement and PAAs are distinctive pulmonary findings in HSS. The latter findings have significant therapeutic ramifications.

A systematic review of artificial intelligence tools for chronic pulmonary embolism on CT pulmonary angiography.

Background: Chronic pulmonary embolism (PE) may result in pulmonary hypertension (CTEPH). Automated CT pulmonary angiography (CTPA) interpretation using artificial intelligence (AI) tools has the potential for improving diagnostic accuracy, reducing delays to diagnosis and yielding novel information of clinical value in CTEPH. This systematic review aimed to identify and appraise existing studies presenting AI tools for CTPA in the context of chronic PE and CTEPH. Methods: MEDLINE and EMBASE databases were searched on 11 September 2023. Journal publications presenting AI tools for CTPA in patients with chronic PE or CTEPH were eligible for inclusion. Information about model design, training and testing was extracted. Study quality was assessed using compliance with the Checklist for Artificial Intelligence in Medical Imaging (CLAIM). Results: Five studies were eligible for inclusion, all of which presented deep learning AI models to evaluate PE. First study evaluated the lung parenchymal changes in chronic PE and two studies used an AI model to classify PE, with none directly assessing the pulmonary arteries. In addition, a separate study developed a CNN tool to distinguish chronic PE using 2D maximum intensity projection reconstructions. While another study assessed a novel automated approach to quantify hypoperfusion to help in the severity assessment of CTEPH. While descriptions of model design and training were reliable, descriptions of the datasets used in training and testing were more inconsistent. Conclusion: In contrast to AI tools for evaluation of acute PE, there has been limited investigation of AI-based approaches to characterising chronic PE and CTEPH on CTPA. Existing studies are limited by inconsistent reporting of the data used to train and test their models. This systematic review highlights an area of potential expansion for the field of AI in medical image interpretation.There is limited knowledge of A systematic review of artificial intelligence tools for chronic pulmonary embolism in CT. This systematic review provides an assessment on research that examined deep learning algorithms in detecting CTEPH on CTPA images, the number of studies assessing the utility of deep learning on CTPA in CTEPH was unclear and should be highlighted.

PE-Ynet: a novel attention-based multi-task model for pulmonary embolism detection using CT pulmonary angiography (CTPA) scan images.

Pulmonary Embolism (PE) has diverse manifestations with different etiologies such as venous thromboembolism, septic embolism, and paradoxical embolism. In this study, a novel attention-based multi-task model is proposed for PE segmentation and detection from Computed Tomography Pulmonary Angiography (CTPA) images. A Y-Net architecture is used to implement this model, which facilitates segmentation and classification jointly, improving performance and efficiency. It is leveraged with Multi Head Attention (MHA), which allows the model to focus on important regions of the image while suppressing irrelevant information, improving the accuracy of the segmentation and detection tasks. The proposed PE-YNet model is tested with two public datasets, achieving a maximum mean detection and segmentation accuracy of 99.89% and 99.83%, respectively, on the CAD-PE challenge dataset. Similarly, it also achieves a detection accuracy of 99.75% and a segmentation accuracy of 99.81% on the FUMPE dataset. Additionally, sensitivity analysis also shows a high sensitivity of 0.9885 for the localization error ɛ = 0 for the CAD-PE dataset, demonstrating the model's robustness against false predictions compared to state-of-the-art models. Further, this model also exhibits lower inference time, size, and memory usage compared to representative models. An automated PE-YNet tool can assist physicians with PE diagnosis, treatment, and prognosis monitoring in the clinical management of CoVID-19.

[Usefulness of Delay Time Setting in Computed Tomography Pulmonary Angiography].

PURPOSE: During computed tomography pulmonary angiography (CTPA), a decrease in the CT value of the pulmonary artery may be observed due to poor contrast enhancement, even though the imaging is performed at the optimum timing while continuously injecting a contrast medium. This study focused on the increase in blood flow in the superior and inferior vena cava during inspiration that affects the decrease in the CT value of the pulmonary artery and investigated a radiography method in which a delay time was set after inspiration in clinical cases. METHODS: A total of 50 patients who underwent CTPA for suspected pulmonary thromboembolism were included. Using the bolus tracking method, we monitored the pulmonary arteries before and after inspiration, and investigated the CT value changes. RESULTS: A decrease in the CT value of the pulmonary artery after inspiration was observed in approximately 30% of cases. By setting the delay time, the contrast enhancement effect before and after inspiration became equivalent. CONCLUSION: As a result of this study, avoiding a decrease in the CT value of the pulmonary artery is possible by setting a delay time after inspiration, which is considered useful during CTPA.

Comparison of pulmonary artery sarcoma and pulmonary thromboembolism according to clinical and computed tomography pulmonary angiography and magnetic resonance imaging characteristics: a single-center retrospective study.

Background: Pulmonary artery sarcoma (PAS) is a very rare malignancy with a poor prognosis; however, its clinical manifestations and imaging findings are often indistinguishable from pulmonary thromboembolism (PTE). We thus aimed to accurately diagnose PAS by comparing the clinical and computed tomography pulmonary angiography (CTPA) and magnetic resonance imaging (MRI) imaging characteristics of PAS and PTE. Methods: This case-control study retrospectively enrolled 20 patients with PAS (from March 2017 to September 2022), 40 patients with central acute PTE, and 40 patients with central chronic PTE (from January 2021 to December 2022) in the China-Japan Friendship Hospital. The following clinical and imaging findings were compared between the three groups: initial symptoms; D-dimer, C-reactive protein, and N-terminal pro B-type natriuretic peptide levels; wall-eclipsing sign (WES); scope of lesion involvement; and morphological characteristics. Signal intensity was also observed on different MRI sequences. Results: The D-dimer level in PAS was significantly lower than that in central acute PTE (P<0.001). The WES was present in 17 cases of PAS (85.0%), which was a greater proportion than that of the central acute PTE and chronic PTE groups (all P values <0.001). The involvement of the pulmonary valve or right ventricular outflow tract was observed in five PAS cases but none of the central acute PTE or chronic PTE cases (all P values =0.001). In 19 PAS cases (95.0%), the lesions grew expansively in the central pulmonary artery. The proximal margin of 18 patients with PAS (90.0%) was bulging or lobulated. Nine cases of PAS (45.0%) showed aneurysm-like dilatation (grape-like sign) of the distal pulmonary artery, representing significantly greater proportion than that of the central acute PTE and chronic PTE groups (all P values <0.001). In 37 patients with central acute PTE (92.5%), the clots were observed to be floating in the pulmonary artery lumen with saddle, tubular or polypoid shape. Eccentric filling defects attached to the pulmonary artery wall were observed in 32 cases of central chronic PTE (80.0%). On MRI, PAS lesions were hyperintense on fat-suppressed T2-weighted imaging and diffusion-weighted imaging, demonstrating heterogeneous enhancement. Conclusions: Comprehensive analysis of the clinical data and imaging features on CTPA and MRI can aid in the accurate differential diagnosis of PAS and PTE.

Video assisted thorascopic assisted correction of left partial anomalous pulmonary venous connection: one case report.

INTRODUCTION: The left partial anomalous pulmonary vein connection is a rare congenital heart disease, especially with intact atrial septum. Now we reported a case of the left superior pulmonary vein drainage to left innominate vein through a vertical vein, and corrected with video assisted thoracoscopy. CASE PRESENTATION: A-59-years old man diagnosed left anomalous partial pulmonary vein connection with presentation of short breathiness and palpation, and diagnosed with computer tomography pulmonary angiography. The operation was carried out under video assisted thoracoscopy with one manipulation incision and one observational incision, the vertical vein was dissected and anastomosis with left atrial appendage. The patients recovered smoothly and postoperative CTPA showed anastomosis ostium was unobstructed. CONCLUSION: The left lateral thoracotomy and video assisted thoracoscopic surgery is a feasible for correction of left PAPVC with intact interatrial septum without using CPB.

Preemptive anticoagulation of pulmonary embolism.

BACKGROUND: Pulmonary embolism (PE) is a life-threatening disease where preemptive anticoagulation is recommended by guidelines for patients with intermediate to high pretest risk of PE. AIMS: The primary objective of our study was to describe the use of preemptive anticoagulation from the emergency department (ED) or inpatient wards stratified by risk assessment score. METHODS: We performed a retrospective observational cohort study of consecutive patients undergoing computed tomography pulmonary angiography (CTPA) for investigation of PE. Patients were classified as either ED patients or hospital ward patients based on where the CTPA was requested. The pretest risk of PE was calculated using the Revised Geneva Score (RGS) and patients were divided into low and intermediate to high risk. RESULTS: A total of 392 consecutive patients who underwent CTPA at Monash Health were reviewed. There were 108 (27.6%) patients who were categorised as low risk (RGS 0-3) and 284 (72.4%) categorised as intermediate to high risk (RGS >3). There were 29 (7.4%) patients overall who received preemptive anticoagulation. Diagnostic yield of CTPA in the ED was low, with only four of 144 (2.8%) CTPA scans positive for PE. The yield of CTPA was higher in ward patients, with 63 of 248 (25.4%) being diagnostic of PE. CONCLUSIONS: The use of preemptive anticoagulation for suspected PE was uncommon and was not influenced by the pretest probability of PE as determined by a validated clinical prediction tool. This may reflect concerns regarding haemorrhagic complications without any clear evidence of benefit. Diagnostic yield of CTPA performed in the ED was low.

Efficacy and Impact of a Multimodal Intervention on CT Pulmonary Angiography Ordering Behavior in the Emergency Department.

OBJECTIVE: To evaluate the efficacy of a multimodal intervention in reducing CT pulmonary angiography (CTPA) overutilization in the evaluation of suspected pulmonary embolism in the emergency department (ED). METHODS: Previous mixed-methods analysis of barriers to guideline-concordant CTPA ordering results was used to develop a provider-focused behavioral intervention consisting of a clinical decision support tool and an audit and feedback system at a multisite, tertiary academic network. The primary outcome (guideline concordance) and secondary outcomes (yield and CTPA and D-dimer order rates) were compared using a pre- and postintervention design. ED encounters for adult patients from July 5, 2017, to January 3, 2019, were included. Fisher's exact tests and statistical process control charts were used to compare the pre- and postintervention groups for each outcome. RESULTS: Of the 201,912 ED patient visits evaluated, 3,587 included CTPA. Guideline concordance increased significantly after the intervention, from 66.9% to 77.5% (P < .001). CTPA order rate and D-dimer order rate also increased significantly, from 17.1 to 18.4 per 1,000 patients (P = .035) and 30.6 to 37.3 per 1,000 patients (P < .001), respectively. Percent yield showed no significant change (12.3% pre- versus 10.8% postintervention; P = .173). Statistical process control analysis showed sustained special-cause variation in the postintervention period for guideline concordance and D-dimer order rates, temporary special-cause variation for CTPA order rates, and no special-cause variation for percent yield. CONCLUSION: Our success in increasing guideline concordance demonstrates the efficacy of a mixed-methods, human-centered approach to behavior change. Given that neither of the secondary outcomes improved, our results may demonstrate potential limitations to the guidelines directing the ordering of CTPA studies and D-dimer ordering.

Study on the clinical application of pre-breathing mode in double-low imaging of 320-slices CT for pulmonary artery / 中国医学装备

Objective:To explore the clinical application value of pre-breathing mode in double-low imaging of 320-slices computed tomography(CT)for pulmonary artery.Methods:A total of 100 patients who underwent CT pulmonary angiography(CTPA)for suspected pulmonary embolism(PE)in Liuzhou People's Hospital from July 2021 to September 2022 were prospectively selected as the research subjects and they were randomly divided into observation group and control group,with 50 cases in each group.The patients of the control group adopted conventional breathing mode(the breathing password was activated after reaching the threshold,and the scan was triggered after 6 s),while the patients of the observation group adopted the pre-breathing mode(the breathing password was activated after 1 or 2 seconds,and the scan was triggered after reaching the threshold).Both two groups adopted double low-technique scan of 320 slices CT.The differences in delay time,radiation dose,the points of subjective and objective image quality,and other indicators were compared between the two groups.Results:The volume CT dose index(CTDIvol),dose length product(DLP),effective dose(ED)and delay time of the observation group were significantly lower than those of the control group(t=76.230,30.225,12.282,7.088,P<0.05),respectively.The comparison of the subjective points of image qualities between the two groups indicated that there were 25 cases with 5 points,23 cases with 4 points and 2 cases with 3 points in the observation group,and there were 21 cases with 5 points,26 cases with 4 points and 3 cases with 3 points in the control group.There was no significant difference in the averagely subjective points of image qualities between two groups(P>0.05).The signal-to-noise ratio(SNR)and signal to noise ratio(CNR)of the observation group were significantly lower than those of the control group,and the noise level(SD)of the observation group was significantly higher than that of the control group(t=25.441,23.886、11.426,P<0.05),respectively.The CT values of the artery trunk of right pulmonary,artery branch of right pulmonary,artery trunk of left pulmonary and artery branch of left pulmonary in the observation group were significantly higher than those in the control group(t=2.256,2.225,2.042,2.277,P<0.05),respectively.Conclusion:The pre-breathing mode can effectively improve CTPA image quality,and reduce radiation dose and the dosage of contrast agent,which clinical application effect is significant.It is worth learning.

An optimized D-dimer cut-off value to predict pulmonary thromboembolism in COVID-19 patients.

Pulmonary thromboembolism (PTE) is a common complication in coronavirus disease 2019 (COVID-19) patients. Elevated D-dimer levels are observed even in the absence of PTE, reducing its discriminative ability as a screening test. It is unknown whether conventional D-dimer cut-off values, as used in the YEARS algorithm, apply to COVID-19 patients. This study aimed to determine the optimal D-dimer cut-off value to predict PTE in COVID-19 patients. All confirmed COVID-19 patients with a computed tomography pulmonary angiography (CTPA) performed ≤5 days after admission due to suspicion of PTE between March 2020 and February 2021, at Medisch Spectrum Twente, The Netherlands, were retrospectively analyzed. The association between PTE and D-dimer levels prior to CTPA, and other potential predictors, was analyzed using logistic regression analyses. The optimal cut-off value was identified using receiver operating characteristic (ROC) curve analyses. In 142 patients, PTE prevalence was 20.4%. The optimal cut-off value was 750 ng/mL (sensitivity 100%; specificity 19.5%; negative predictive value 100%; positive predictive value 24.2%). In total, 15 of 113 (13%) patients without PTE had a D-dimer level ≥500 and <750 ng/mL. In our population of patients hospitalized with COVID-19, a D-dimer level <750 ng/mL safely excluded PTE. Compared to the YEARS 500 ng/mL cut-off value, 13% fewer patients are in need of a CTPA, with similar sensitivity. Future research is required for external validation.

ECG Features of Pulmonary Embolism in a Patient With Normal D-Dimer and Hypoxia.

Pulmonary embolism is a life-threatening condition that requires urgent treatment. We present the case of a 76-year-old male referred to our medical team with dyspnoea, shortness of breath on exertion, and chest pain. Upon further questioning, the patient reported a two-week history of right-sided parasternal pleuritic chest pain without radiation. He denied any history of haemoptysis, calf swelling or pain, recent surgery, and reduced mobility. The patient had a medical history of bilateral cataracts, glaucoma, and hypertension. Clinical examination was unremarkable except for requiring 2L/minute supplemental oxygen to maintain an oxygen saturation of 94%, and blood tests were unremarkable, including a normal D-dimer. Chest radiography revealed no obvious pathological findings. However, the electrocardiogram showed a right bundle branch, sinus tachycardia, and an S1Q3T3 pattern. A computed tomography pulmonary angiogram confirmed pulmonary emboli within the right lower lobe segmental artery, extending into the bilateral basal segmental branch and posterior basal segmental branch. The patient was commenced on low molecular weight heparin initially followed by rivaroxaban 20 mg once daily. This case highlights the importance of having a high degree of suspicion for pulmonary embolism, and D-dimer is an important screening test that can be normal.

Comparison of cardiovascular metrics on computed tomography pulmonary angiography of the updated and old diagnostic criteria for pulmonary hypertension in patients with chronic thromboembolic pulmonary hypertension.

Background: In the 2022 European Society of Cardiology (ESC) and the European Respiratory Society (ERS) guidelines, the diagnostic criteria for pulmonary hypertension (PH) included a reduced mean pulmonary artery pressure (mPAP) of 20 mmHg (mPAP >20 mmHg). This study aimed to reassess cardiovascular metrics on computed tomography pulmonary angiography (CTPA) for chronic thromboembolic pulmonary hypertension (CTEPH) to optimize the timely diagnosis of patients with suspected PH. Methods: Patients with suspected CTEPH who underwent CTPA and right heart catheterization (RHC) between January 2019 and December 2022 in China-Japan Friendship Hospital were retrospectively included. They were grouped into CTEPH and non-PH groups according to the new and old criteria (2022 and 2015 ESC/ERS guidelines) for the diagnosis of PH. Cardiovascular metrics including the main pulmonary artery diameter (MPAd), Cobb angle, and right ventricular free wall thickness (RVWT), among others, were measured. The correlation of these metrics with hemodynamic data was analyzed with Spearman rank correlation analysis, while the differences in cardiovascular metrics between the updated (mPAP >20 mmHg) and old PH criteria (mPAP ≥25 mmHg) were compared with independent samples t-test or the Mann-Whitney test. Receiver operator characteristic (ROC) curve analysis was performed for the prediction model. Results: The study enrolled 180 patients (males n=86; age 55.5±12.0 years old). According to the old guidelines, 119 patients were placed into the PH group (mPAP ≥25 mmHg) , while according to the new guidelines, 130 patients were placed into the PH group (mPAP >20 mmHg). Cardiovascular metrics on CTPA between the updated and old guidelines were comparable (P>0.05). Compared to other metrics, an MPAd of 30.4 mm exhibited the highest area under the curve (AUC: 0.934±0.021), with a sensitivity of 0.88 and specificity of 0.90. MPAd [odds ratio (OR) =1.271], transverse diameter of the right ventricle (RVtd; OR =1.176), Cobb angle (OR =1.108), and RVWT (OR =3.655) were independent factors for diagnosing CTEPH (P<0.05). Cobb angle, right and left ventricular transverse diameter ratio, and right and left ventricular area ratio moderately correlated with mPAP (r=0.586, r=0.583, r=0.629) and pulmonary vascular resistance (PVR) (r=0.613, r=0.593, r=0.642). Conclusions: Cardiovascular metrics on CTPA were comparable between the new and old guidelines for CTEPH diagnosis. Cardiovascular metrics on CTPA can noninvasively assess the hemodynamics of patients with CTEPH.

Computed Tomography Pulmonary Angiography Prediction of Adverse Long-Term Outcomes in Chronic Thromboembolic Pulmonary Hypertension: Correlation with Hemodynamic Measurements Pre- and Post-Pulmonary Endarterectomy.

CT pulmonary angiography is commonly used in diagnosing chronic thromboembolic pulmonary hypertension (CTEPH). This work was conducted to determine if cardiac chamber size on CTPA may also be useful for predicting the outcome of CTEPH treatment. A retrospective analysis of paired CTPA and right heart hemodynamics in 33 consecutive CTEPH cases before and after pulmonary thromboendarterectomy (PTE) was performed. Semiautomated and manual CT biatrial and biventricular size quantifications were correlated with mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR) and cardiac output. The baseline indexed right atrioventricular volumes were twice the left atrioventricular volumes, with significant (p < 0.001) augmentation of left heart filling following PTE. Except for the left atrial volume to cardiac index, all other chamber ratios significantly correlated with hemodynamics. Left to right ventricular ratio cut point <0.82 has high sensitivity (91% and 97%) and specificity (88% and 85%) for identifying significant elevations of mPAP and PVR, respectively (AUC 0.90 and 0.95), outperforming atrial ratios (sensitivity 78% and 79%, specificity 82% and 92%, and AUC 0.86 and 0.91). Manual LV:RV basal dimension ratio correlates strongly with semiautomated volume ratio (r 0.77, 95% CI 0.64-0.85) and is an expeditious alternative with comparable prognostic utility (AUC 0.90 and 0.95). LV:RV dimension ratio of <1.03 and ≤0.99 (alternatively expressed as RV:LV ratio of >0.97 and ≥1.01) is a simple metric that can be used for CTEPH outcome prediction.

Scimitar syndrome with large atrial septal defect and a rare partial anomalous venous drainage in an adult: a case report.

Background: Scimitar syndrome is a very rare congenital cardio-pulmonary disease with anomalous right pulmonary vein draining either partially or completely into the inferior vena cava. It is called Scimitar syndrome due to the classical appearance in the chest X-ray, which resembles the curved blade of Turkish sword 'Scimitar'. It commonly associates with atrial septal defect (ASD), hypoplasia of the right lung, dextroposition of the heart, and pulmonary hypertension (PHT). Case summary: A 67-year-old lady, diagnosed with atrial fibrillation and moderate PHT 3 years ago, presented with worsening bilateral ankle oedema and New York Heart Association class III shortness of breath. Chest X-ray showed the Scimitar appearance. The trans-thoracic and trans-oesophageal echocardiograms revealed a 46 mm ASD and a partial anomalous pulmonary venous drainage (PAPVD) of the right upper pulmonary vein (RUPV) into the right atrium at the junction of the atria. Three-dimensional reconstruction of the computed tomographic pulmonary angiogram confirmed Scimitar syndrome of the right lower pulmonary vein (RLPV). We managed her conservatively on her wish. After 13 months, she succumbed due to a massive stroke. Discussion: We describe a very rare case of an elderly lady who has Scimitar syndrome with an ASD and evidence of PAPVD of the RUPV; thus, we intend to provide an antecedent for further cases, for prompt and accurate diagnosis and timely interventions in order to prevent life-threatening complications.