Computed Tomography Pulmonary Angiography Research Articles

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.

Metastatic right atrial mass in the presence of atrial septal defect: A rare clinical coincidence

Key Clinical MessageThe key takeaway from this clinical scenario is to choose the most appropriate and reasonable treatment plan when dealing with a patient who has atrial septal defect (ASD) and concurrent atrial and mediastinal masses. In such cases, a heart‐oncology team should make the therapeutic decision.AbstractRight atrial masses are not pretty rare and might be a diagnostic challenge. Thrombosis, tumors, and vegetations are primary differential diagnoses. Workup for these masses usually includes multimodality imaging and biopsy in selected cases. We report a case of a 37‐year‐old lady who presented with cough, dyspnea, and head and neck swelling after a cesarean section. Echocardiography revealed a right atrial mass accompanied by a secundum type atrial septal defect (ASD). Pulmonary CT Angiography was performed, in which a lobulated mass in the anterior mediastinum was detected, and a heart‐oncology team made the therapeutic decision. The patient was scheduled for surgical ASD closure and concomitant tissue biopsy. The pathology results were in favor of poorly differentiated germ cell tumors, and chemotherapy was started following the surgery. After two sessions of chemotherapy, the tumor did not respond to the primary regimen. Thus, an updated regimen was initiated. Compliance with the updated regimen was acceptable, and the patient is currently under treatment and follow‐up.

Chest non‑contrasted computed tomography in detecting acute pulmonary thromboembolism: A single‑center retrospective study.

The object of the study was to evaluate comprehensively the value of chest non-contrasted CT (NC-CT) in detecting acute pulmonary thromboembolism (APE). All patients were categorized into two groups: i) With APE; and ii) without APE based on clinical diagnosis. Using the clot distribution on computed tomography pulmonary angiography (CTPA), APE was divided into central and peripheral APE. Imaging features including hyperdense lumen sign and peripheral wedge-shaped opacity on chest NC-CT were evaluated. The attenuation value of peripheral wedge-shaped opacity on NC-CT was compared between patients with and without APE. Among the 273 patients, there were 110 patients with APE, 49 patients with central APE and 61 patients with peripheral APE and 163 patients without APE. The hyperdense lumen sign had a sensitivity of 30.0% and a specificity of 97.6% in detecting APE. The sensitivity and specificity of hyperdense lumen sign in detecting central APE were 57.1 and 97.6%, respectively, while the relevant percentages in detecting peripheral APE were 8.2 and 97.6%, respectively. The mean attenuation value of peripheral wedge-shaped opacity in patients with APE was significantly lower than that in patients without APE (P<0.001). Regarding the age-adjusted D-dimer, there was a decrease of eight D-dimer positive cases for patients >50 years old without APE, confirmed by CTPA. In conclusion, chest NC-CT cannot be used as an alternative modality for CTPA in diagnosing APE, however, the hyperdense lumen sign had high specificity in the diagnosis of central APE. Patients with this symptom and increased D-dimer may not require further CTPA. The lower attenuation value of peripheral wedge-shaped opacity on NC-CT suggested APE, and CTPA confirmation was required. The age-adjusted D-dimer had higher specificity in excluding APE.

Agreement Between Transthoracic Echocardiography and Computed Tomography Pulmonary Angiography for Detection of Right Ventricular Dysfunction in Pulmonary Embolism.

Right ventricular dysfunction (RVD) is the main determinant of mortality in patients with pulmonary embolism (PE). Thus, guidelines recommend the assessment of RVD with transthoracic echocardiography (TTE) or computed tomography pulmonary angiography (CTPA) among these patients. In this study, we investigated the agreement between TTE and CTPA for the detection of RVD. This single-center retrospective study included patients who were diagnosed with CTPA and underwent TTE within the first 24 hours following the diagnosis. Two hundred fifty-eight patients met the inclusion criteria. In 71.3% (184) of them, CTPA and TTE agreed on both the presence and absence of RVD. There was a moderate agreement between the 2 tests (Cohen's kappa = 0.404, P <.001). The agreement between right ventricle dysfunction on TTE and the increased right ventricle/left ventricle (RV/LV) on CTPA was fair (Cohen's kappa = 0.388, P <.001). Three patients died due to PE, and another 5 patients required urgent reperfusion therapy. Overall, adverse outcomes occurred in 4% (8) of patients. The sensitivity of modalities in the detection of adverse outcomes was 100%. Transthoracic echocardiography was more specific compared to CTPA (43% vs. 28%). Statistically, flattening/bulging of the interventricular septum on TTE was significantly associated with adverse outcomes. No individual CTPA parameter was related to adverse outcomes. Both CTPA and TTE are reliable imaging modalities in the detection of RVD. However, TTE is more specific, and this may help in the identification and appropriate management of patients at higher risk of decompensation. A combination of CTPA parameters rather than individual RV/LV ratios increases the sensitivity of CTPA.

Electrocardiogram Signal Analysis With a Machine Learning Model Predicts the Presence of Pulmonary Embolism With Accuracy Dependent on Embolism Burden

ObjectiveTo develop an artificial intelligence deep neural network (AI-DNN) algorithm to analyze 12-lead electrocardiogram (ECG) for detection of acute pulmonary embolism (PE) and PE categories. Patients and MethodsA cohort of patients seen between January 1, 1999, and December 31, 2020, from across the Mayo Clinic Enterprise with computed tomography pulmonary angiogram (CTPA) and ECG performed ±6 hours was identified. Natural language processing algorithms were applied to radiology reports to determine the diagnosis of acute PE, acute right ventricular strain pulmonary embolism (RVSPE), saddle pulmonary embolism (SADPE), or no PE. Diagnostic performance parameters of the AI-DNN reported were area under the receiver operating characteristics curve (AUROC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). ResultsA cohort of patients with CTPA report and ECG consisted of 79,894 patients including 7423 (9.3%) with acute PE, among whom 1138 patients had RVSPE or SADPE. Artificial intelligence deep neural network predicted acute PE with a modest accuracy of AUROC of 0.69 (95% CI, 0.68-0.71), sensitivity of 63.5%, specificity of 64.7%, PPV of 15.6%, and NPV of 94.5%. The AI-DNN prediction using the same algorithm for RVSPE or SADPE was higher (AUROC, 0.84; 95% CI, 0.81-0.86) with a sensitivity of 80.8%, specificity of 64.7.8%, PPV of 3.5%, and NPV of 99.5%. ConclusionAn AI-based analysis of 12-lead ECG shows modest detection power for acute PE in patients who underwent CTPA, with higher accuracy for high-risk PE. Moreover, with the high NPV, it has the clinical potential to exclude high-risk PE quickly and correctly.

Association between pre-treatment computed tomography findings and post-treatment persistent decrease in lung perfusion blood volume

The purpose of this study was to evaluate pre-treatment CT findings in patients with acute pulmonary embolism (PE) and determine the imaging findings associated with residual hypoperfused segments in post-treatment lung perfused blood volume (LPBV). We evaluated 91 patients with acute PE who underwent dual-energy CT before and after treatment. The location of thrombi (proximal or distal) and patency of the pulmonary artery (occlusive or non-occlusive) were recorded using pre-treatment computed tomography pulmonary angiography (CTPA). Residual hypoperfusion was defined as a perfusion-decreased area seen in both the pre- and post-treatment LPBVs. The association of the location of the thrombus and vascular patency of pre-treatment CTPA with residual hypoperfusion on a segmental and patient basis was examined. In the segment-based analysis, the proportion of residual hypoperfusion in the proximal group was significantly higher than that in the peripheral group (33/125 [26.4%] vs. 9/87 [10.3%], P = 0.004). Patient-based analysis also showed that the proportion of residual hypoperfusion in patients with pre-treatment proximal thrombus was significantly higher than those without (16/42 [38.1%] vs. 3/25 (12.0%); P = 0.022). Pre-treatment vascular patency was not significantly associated with residual hypoperfusion (P > 0.05). Therefore, careful follow-up is necessary, especially in patients with proximal thrombi.

Chronic thromboembolic pulmonary hypertension in acute pulmonary embolism: a risk factor evaluation study

Aims: Pulmonary thromboembolism (PTE) is a highly mortal disease, defined by presence of thrombus partially or completely obstructing pulmonary arteries and/or veins, commonly originated from deep venous system. Chronic thrombroembolic pulmonary hypertension (CTEPH) is a rare complication of PTE with high mortality if not treated properly. In recent studies, incidence of CTEPH was found between %0,4-9,1. Due to clinically silent PTE in roughly %50 of patients, it is difficult to pinpoint the exact incidence of CTEPH. In this study, we aim to investigate PTE patients during their long-term follow up to observe CTEPH presence and evaluate CTEPH risk factors. Methods: Patients who had been evaluated in emergency service and/or admitted to pulmonary medicine ward between January 2014 and January 2017 with PTE diagnosis confirmed by computed tomography pulmonary angiogram (CTPA) were accepted retrospectively into the study. Their echocardiography, CTPA and lower extremity venous Doppler ultrasonography at 3., 6. and 12. months follow up were also included. In the patient group with pulmonary arterial pressure (PAP ) above 50 mmHg and residual thrombosis at CTPA, ventilation-perfusion scintigraphy had been performed and was added to the study. Among those suitable for CTEPH, right cardiac catheterization had been done to confirm the diagnosis and accepted as CTEPH. In addition to this group, patients who were not found suitable for right cardiac catheterization but wereclinically suitable for CTEPH are also included in the CTEPH group. Results: Average age of patients included into the study was 62(±16, 5), with 71 (%39) being male and 111 (%61) female. As for risk factors, 130 (%71,4) had acquired, 16 (%8,8) had genetic and the rest 36 (%19,8) did not have any prominent risk factors. At time of diagnosis, 10 patients were accepted as massive, 26 as sub massive and the rest 139 were considered non-massive PTE. Due to hemodynamic instability, 7 (%3,8) patients were given thrombolytic therapy. During 1 year follow-up, 5 (%2,7) patients were diagnosed with CTPH. When further investigation was performed on these 5 patients, atrial fibrillation (AF), persistent thrombosis at 12. month follow up CTPA and PAP above 55 mmHg upon time of diagnosis were found significant risk factors (p being 0,001/0,023/0,009 respectively). In multivariate analysis, no independent predictive factors were found in regards to CTEPH diagnosis. Conclusion: CTEPH is a preventable complication of PTE with severe mortality and morbidity if not properly treated. It might prove useful to utilize echocardiography and CTPA together, especially in those in high risk groups, for diagnosis of patients in early stage of CTEPH with no evident signs or symptoms.

CT venography for the diagnosis of postpartum venous thromboembolism: a prospective multi-center cohort study.

To assess the role of CT venography (CTV) in the diagnosis of venous thromboembolism (VTE) during the postpartum period. This multicenter prospective cohort study was conducted between April 2016 and April 2020 in 14 university hospitals. All women referred for CT pulmonary angiography (CTPA) for suspected pulmonary embolism (PE) within the first 6 weeks postpartum were eligible. All CTPAs were performed on multidetector CT machines with the usual parameters and followed by CTV of the abdomen, pelvis, and proximal lower limbs. On-site reports were compared to expert consensus reading, and the added value of CTV was assessed for both. The final study population consisted of 123 women. On-site CTPA reports mentioned PE in seven women (7/123, 5.7%), all confirmed following expert consensus reading, three involving proximal pulmonary arteries and four limited to distal arteries. Positive CTV was reported on-site in nine women, five of whom had negative and two indeterminate CTPAs, bringing the VTE detection rate to 11.4% (14/123) (95%CI: 6.4-18.4, p = 0.03). Expert consensus reading confirmed all positive on-site CTV results, but detected a periuterine vein thrombosis in an additional woman who had a negative CTPA, increasing the VTE detection rate to 12.2% (15/123) (95%CI: 7.0-19.3, p = 0.008). Follow-up at 3 months revealed no adverse events in this woman, who was left untreated. Median Dose-Length-Product was 117 mGy.cm for CTPA and 675 mGy.cm for CTPA + CTV. Performing CTV in women suspected of postpartum PE doubles the detection of venous thromboembolism, at the cost of increased radiation exposure. CTV can help in the decision-making process concerning curative anticoagulation in women with suspected postpartum PE, particularly those whose CTPA results are indeterminate or whose PE is limited to the subsegmental level. Postpartum women are at risk of pulmonary embolism, and CT pulmonary angiography can give equivocal results. CT venography (CTV) positivity increased the venous thromboembolism detection rate from 5.7 to 11.4%. CTV may help clinical decision-making, especially in women with indeterminate CTPA results or subsegmental emboli.

Pediatric pulmonary embolism: Unveiling clinical manifestations, diagnostic challenges, and outcomes in Southwest China

AbstractPulmonary embolism (PE) leads to obstruction of pulmonary circulation, resulting in increased pulmonary vascular resistance, elevated pulmonary arterial pressure, and increased right heart load. In severe cases, it can lead to cardiac decompensation and life‐threatening conditions. However, clinical studies on PE in children are limited, with many diagnostic and treatment guidelines derived from adult populations. We retrospectively analyzed the clinical manifestations, risk factors, co‐morbidity, and outcomes of PE patients admitted to a large children's hospital in southwest China. A total of 24 children with PE participated, 9 boys (37.5%), aged 0.1–14.6, (median: 8.15 years old). Except for two asymptomatic cases, the duration from symptom onset to the diagnosis of PE varied from 2 to 45 days (median: 12 days). Among these children, 13 (54.2%) patients experienced a delayed diagnosis exceeding 10 days. A total of 7 children died from underlying diseases, and no one met the outcome of recurrent PE or PE‐related death. Among the 17 survivors, complete resolution of PE was in 11 (64.7%) children, partial resolution who progressed to chronic PE was in 3 (17.7%) children, and no follow‐up computed tomography pulmonary angiography was performed in the remaining 3 (17.7%) children. This study revealed that the majority of pediatric PE cases presented with respiratory symptoms, with a considerable proportion initially misdiagnosed as pneumonia, and emphasized the importance of early recognition and appropriate management strategies in improving outcomes for the affected children. Further research is warranted to elucidate the pathophysiology, refine diagnostic algorithms, and establish standardized treatment protocols tailored to the pediatric population.

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 aimHughes-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. MethodsThis 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. ResultsThe 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). ConclusionMajor 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.

Investigation in image quality and immediate patient safety using pre-dual-flow injection for low-contrast dose spectral pulmonary artery CT angiography

PurposeThe patient safety of iodine contrast-enhanced pulmonary artery CT angiography (CTPA) is widely concerned. This study aimed to investigate the image quality and immediate patient safety of spectral CTPA using a lower-contrast dose pre-dual-flow injection method. MethodsThis retrospective study included 120 patients with suspected pulmonary embolisms who received spectral CTPA between February and December 2022. Patients were divided into normal contrast injection (Group A, n=60) and pre-dual-flow group (Group B, n=60). CT values of pulmonary arteries (PAs) at different levels, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), arteriovenous separation performance, and beam hardening artifact (BHA) index of two sets of images were measured or calculated. The subjective image quality and immediate patient safety were also scored using the three-point method. ResultsGroup B had a contrast dose reduction by 42.5 % (60 vs. 34.5 mL). Radiation exposure dose was not statistically different between the two groups (P>0.05). CT values of different-level PAs on group B images were higher than those on group A images (P<0.05). Group B images had higher SNR and CNR, better arteriovenous separation between PA trunk and pulmonary vein, and lower BHA index on soft tissue and PA (all P<0.05). For subjective evaluation of image quality, group B had a better score in beam hardening artifact (P<0.05). For immediate patient safety, the score in comfortability was statistically higher in group B, with P<0.05. ConclusionsComparing with the normal injection method, pre-dual-flow spectral CTPA with a lower contrast dose injected results in better image quality and shows potential in patient-safety promotion.

Optimizing resource allocation: Cost-effectiveness of specified D-dimer cut-offs in cancer patients with suspected venous thromboembolism

An accurate diagnosis of venous thromboembolism (VTE) is crucial, given the potential for high mortality in undetected cases. Strategic D-dimer testing may aid in identifying low-risk patients, preventing overdiagnosis and reducing imaging costs. We conducted a retrospective, comparative analysis to assess the potential cost savings that could be achieved by adopting different approaches to determine the most effective D-dimer cut-off value in cancer patients with suspected VTE, compared to the commonly used rule-out cut-off level of 0.5 mg/L. The study included 526 patients (median age 65, IQR 55–75) with a confirmed cancer diagnosis who underwent D-dimer testing. Among these patients, the VTE prevalence was 29% (n = 152). Each diagnostic strategy's sensitivity, specificity, negative likelihood ratio (NLR), as well as positive likelihood ratio (PLR), and the proportion of patients exhibiting a negative D-dimer test result, were calculated. The diagnostic strategy that demonstrated the best balance between specificity, sensitivity, NLR, and PLR, utilized an inverse age-specific cut-off level for D-dimer [0.5 + (66-age) × 0.01 mg/L]. This method yielded a PLR of 2.9 at a very low NLR for the exclusion of VTE. We observed a significant cost reduction of 4.6% and 1.0% for PE and DVT, respectively. The utilization of an age-adjusted cut-off [patient’s age × 0.01 mg/L] resulted in the highest cost savings, reaching 8.1% for PE and 3.4% for DVT. Using specified D-dimer cut-offs in the diagnosis of VTE could improve economics, considering the limited occurrence of confirmed cases among patients with suspected VTE.Graphical In the context of accurate diagnosis of VTE, strategic D-dimer testing helps identify low-risk patients, preventing overdiagnosis and reducing imaging costs. In our retrospective study, the diagnostic strategy that demonstrated the best balance between specificity, sensitivity, and best PLR, utilized an inverse age-specific cut-off level for D-dimer. We observed a significant cost reduction of 4.6% for PE and 1% for DVT. Abbreviations: CTPA, computed tomography pulmonary angiography; CUS, compression ultrasound; DVT, deep vein thrombosis; PE, pulmonary embolism; VTE, venous thromboembolism.

New Diagnostic Tools for Pulmonary Embolism Detection.

The presentation of pulmonary embolism (PE) varies from asymptomatic to life-threatening, and management involves multiple specialists. Timely diagnosis of PE is based on clinical presentation, D-dimer testing, and computed tomography pulmonary angiogram (CTPA), and assessment by a Pulmonary Embolism Response Team (PERT) is critical to management. Artificial intelligence (AI) technology plays a key role in the PE workflow with automated detection and flagging of suspected PE in CTPA imaging. HIPAA-compliant communication features of mobile and web-based applications may facilitate PERT workflow with immediate access to imaging, team activation, and real-time information sharing and collaboration. In this review, we describe contemporary diagnostic tools, specifically AI, that are important in the triage and diagnosis of PE.

ENTRECTINIB–INDUCED ACUTE RIGHT HEART FAILURE IN A PATIENT WITH METASTATIC LUNG ADENOCARCINOMA

Abstract We report a case report of a 45–year–old woman with a recent diagnosis of stage IV lung adenocarcinoma (PDL1 60%) with brain metastases, who started entrectinib 600 mg orally once daily. Four days after entrectinib initiation, the patient activated the emergency medical services for acute onset of marked fatigue and hypotension. The ECG performed by the emergency unit showed a marked ST–segment elevation in the infero–lateral leads. Therefore, emergent coronary angiography was performed and no evidence of coronary disease was reported. Subsequently, the patient was admitted to the Coronary Care Unit. Clinical evaluation revealed labile hemodynamics, as the patient presented mental confusion, persistent hypotension (BP 90/50 mmHg) and bradycardia (HR 30 bpm). Laboratory testing showed elevated NT–pro BNP, troponin I and transaminases, normal CRP. The electrocardiogram showed persistent diffuse ST–segment elevation. Transthoracic echocardiogram showed severe dilatation and hypokinesia of the right ventricular (GLS VDx –4.5%), with diastolic “D–shape”, normal left ventricular ejection fraction, no significant valvular disease, circumferential pericardial effusion. Clinical, laboratory and instrumental findings suggested a condition of acute right heart failure. We performed urgent computed tomography pulmonary angiography (CTPA) which resulted negative for acute pulmonary embolism. Hence, supportive therapy with dobutamine, norepinephrine and fluid resuscitation was started, with subsequent hemodynamic stabilization. Since no other etiology was demonstrated by the extensive testing, we attributed the acute right ventricular dysfunction to the recent introduction of entrectinib therapy. Therefore, the drug was discontinued. During the hospitalization we observed a rapid normalization of electrocardiogram and right ventricle function by transthoracic echocardiogram, accompanied by a progressive improvement of laboratory parameters. In order to better define right ventricle function and dimension, the patient underwent cardiac magnetic resonance imaging which showed a normal right ventricle ejection fraction (RV EF 52%), the absence of myocardial edema or late gadolinium enhancement and normal volume of the right ventricle. After six days of hospitalization the patient was discharged. Our case report adds to the limited available literature of cardiac toxicity of entrectinib.

AUTOIMMUNE MYOCARDITIS IN MELANOMA IMMUNOTHERAPY–COMPLEX CLINICA PRESENTATION AND ADVERSE THERAPEUTIC RESPONSE

Abstract A 68–year–old Caucasian female presented to the ED with cardiac chest pain and dyspnea. The patient had a history of arterial hypertension and was equipped with a biventricular pacemaker due to atrial fibrillation with low ventricular response. She had recently been diagnosed with metastatic melanoma and initiated treatment with nivolumab and ipilimumab two weeks prior. Troponin levels were elevated (700 ng/ml), and no ST–segment elevation was observed on the electrocardiogram (ECG). In suspicion of NSTEMI–ACS, coronary angiography was performed, revealing an intact epicardial coronary circulation without stenotic lesions. The echocardiogram showed borderline left ventricular systolic function (EF 50%), and the right ventricle exhibited initial signs of reduced systolic function (TAPSE, 15 mm; S RV, 9.5 m/s). The following day, there was a deterioration in hemodynamics and respiratory exchange, with evidence of apical and mid–distal interventricular septum hypokinesia of the left ventricle (EF 40%) and dilated right ventricle (BD 4.8 cm; MD 4 cm) with severely reduced systolic function (TAPSE 10 mm, S RV 7 m/s, FAC, 20%), and severe tricuspid regurgitation. Urgent computed tomography pulmonary angiography (CTPA) excluded pulmonary embolism. Additionally, there was a new troponin increase (5000 ng/ml) and elevated hepatic biomarkers. The clinical picture raised suspicion of myocarditis related to immune checkpoint inhibitor therapy. Corticosteroid therapy was initiated with a daily administration of methylprednisolone 1000 mg. Diagnostic confirmation was sought through autoimmune panel and viral marker assessments, which yielded negative results. Endomyocardial biopsy (EMB) revealed CD4 and CD8–positive lymphocytic infiltration and myocardial necrosis. Despite initial clinical improvement, an arrhythmic storm developed. Despite treatment with a defibrillator, intravenous antiarrhythmic therapy (beta–blocker, amiodarone, and lidocaine), and sedation, the patient unfortunately succumbed. Immune checkpoint inhibitors (ICIs) have been revolutionary in the treatment of many solid tumors. However, the dysregulation of immune mechanisms can rarely (2%) lead to autoimmune events involving multiple organs. Myocarditis, despite optimal treatment, is characterized by a mortality rate exceeding 50%, representing a significant challenge in the Intensive Care Unit.

HALF DOSE THROMBOLYSIS IN INTERMEDIATE – HIGH RISK PULMONARY EMBOLISM WITH TRICUSPID VALVE MOBILE MASS: A BAIL OUT STRATEGY

Abstract A 82–year–old previously healthy male was referred to the emergency department complaining sudden onset dyspnea and witnessed syncope complicated by head trauma. Recurrent dizziness occurred previously. No history or drug consumption noted. On admission: heart rate 90 beats/min, blood pressure 110/60 mmHg, respiratory rate 25 breaths/min, oxygen saturation 87% in room air, normal body temperature. No lower extremities tenderness or swelling reported. Consistent with peripheral blood oxygen saturation levels, arterial blood gas analysis showed hypoxemia and respiratory alkalosis. Laboratory exams were significant for thrombocytopenia (89.000 cells/L), elevated cardiac troponin T levels (222 ng/L) and natriuretic peptide (NT pro–BNP 3944 pg/mL). Head CT excluded acute cerebral hemorrhage. At the electrocardiogram, signs of RV strain were present (biphasic T–waves in V1–V3 leads, S1–Q3–T3). Transthoracic echocardiography (TTE) showed dilated RV with hypokinetic free wall, “D–shaped” LV, “60/60” sign and a mobile filiform mass crossing the tricuspid valve plan in the right atrium (fig. 1). The patient did not present structural valvular abnormalities or endocarditis–related risk factors. CT pulmonary angiography detected a “saddle” PE and extensive thrombosis in inferior vena cava. After unfractioned heparin (UFH) bolus, the patient was transferred to our intensive care unit and balancing risks and benefits the chosen treatment option consisted in half dose systemic thrombolysis (50 mg rtPA in 60’’; 10 mg as loading dose in 2’). Because of potential harmful effects in thrombocytopenia and recent head trauma, UFH was temporarily withheld and started again after 1 hour. The day after, a beside TTE showed complete tricuspid thrombus resolution, a significant decrease in RV/LV ratio and systolic pulmonary artery pressure (fig. 2). Apart from small hematomas, no bleedings were reported. The patient was shifted to the ward on the next day and following course was uneventful. On day 4 a direct oral anticoagulant (Dabigatran 110 mg) was started. Abdominal and inferior limb–deep–venous ultrasound were both negative for pathological reports. A total body CT was scheduled to exclude silent malignancies at discharge. Take home message: in intermediate–high risk PE, half dose systemic fibrinolysis strategy is controversial since its potential benefit is counterbalanced by concerns about major bleedings, but increasing data suggest its efficacy with low risk profile.