Morphologic and Functional Dual-Energy CT Parameters in Patients With Chronic Thromboembolic Pulmonary Hypertension and Chronic Thromboembolic Disease.

OBJECTIVE. The objective of our study was to compare morphologic and functional dual-energy CT (DECT) parameters in patients with chronic thromboembolic disease (CTED) and chronic thromboembolic pulmonary hypertension (CTEPH). MATERIALS AND METHODS. Using the local CTEPH registry, we identified 28 patients with CTED and 72 patients with CTEPH. On each DECT examination, a clot burden score was calculated by assigning the following scores for chronic changes by location: pulmonary trunk, 5; each main pulmonary artery (MPA), 4; each lobar branch, 3; each segmental branch, 2; and each subsegmental branch, 1. The total clot burden score was calculated by adding the individual scores from both lungs. Functional parameters were assessed using perfused blood volume (PBV) maps and included lung enhancement (in Hounsfield units), percentage of PBV, MPA peak enhancement (in Hounsfield units), maximum enhancement corresponding to 100, and the ratio of MPA peak enhancement to lung enhancement. A perfusion defect (PD) score was calculated by assigning 1 point to each segmental PD. Patients with CTED and patients with CTEPH were matched using propensity score matching to account for potential confounders. RESULTS. After matching, the CTEPH group showed a higher PD score than the CTED group and unilateral disease was more common in the CTED group than in the CTEPH group. In the unmatched sample, patients with CTED showed increased percentages of PBV for both lungs (PBV total) and for the right lung as compared with the CTEPH group (adjusted p = 0.040 and 0.028, respectively); after adjustment for clot burden, the difference between groups was still noted but was not statistically significant. No statistically significant differences were noted in the various functional DECT parameters after propensity score matching. CONCLUSION. Patients with CTED show anatomic and functional changes in the pulmonary vasculature and lung parenchyma similar to those seen in patients with CTEPH. Functional DECT parameters support the observation that CTED is an intermediate clinical phenotype in the population with chronic pulmonary embolism.

CT-Based Biomarkers for Prediction of Chronic Thromboembolic Pulmonary Hypertension After an Acute Pulmonary Embolic Event.

OBJECTIVE. The purpose of this study is to assess CT-based markers predictive of the development of chronic thromboembolic pulmonary hypertension (CTEPH) after acute pulmonary embolism. MATERIALS AND METHODS. Identified from a search of local registries, 48 patients who had CTEPH develop were included in the study group, and 113 patients who had complete resolution of acute pulmonary embolism were included in the control group. Baseline CT scans obtained at the time of the initial pulmonary embolism event were evaluated for the degree of clot-induced vessel obstruction, the quantitative Walsh score, the ratio of the right ventricle diameter to the left ventricle diameter, the right atrium diameter, the pulmonary artery diameter, right heart thrombus, pericardial effusion, lung infarction, and mosaic attenuation. Classification and regression tree analysis was used to create a decision tree. The decision tree was externally validated on an anonymized cohort of 50 control subjects and 50 patients with CTEPH. RESULTS. During univariable analysis, an increase in the degree occlusive clot on initial imaging, a decrease in the Walsh score, absence of pericardial effusion, presence of lung infarction, and the presence of mosaic attenuation were associated with an increased probability of CTEPH development. In the final decision tree, the occlusive nature of the clot remained. Two patients in the cohort used for external validation had nondiagnostic findings and were excluded. The decision process correctly classified 33% (16/48) of patients who had CTEPH develop and 86% (43/50) of patients who did not have CTEPH develop, for an odds ratio of 3.1 (95% CI, 1.1-8.3). CONCLUSION. The presence of an occlusive clot on initial imaging is associated with an increased probability of CTEPH development. Presence of mosaic attenuation and lung infarction may also predict CTEPH development, although additional studies are needed.

Dual energy CT based scoring in chronic thromboembolic pulmonary hypertension and correlation with clinical and hemodynamic parameters: a retrospective cross-sectional study.

Background: We used a dual energy computed tomography (DECT) based scoring system in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and correlated it with functional and hemodynamic parameters. Methods: This was a retrospective study on 78 patients with CTEPH who underwent DECT. First, clot burden score was calculated by assigning a following score: pulmonary trunk-5, each main pulmonary artery-4, each lobar-3, each segmental-2, and subsegmental-1 per lobe; sum total was then calculated. Perfusion defect (PD) score was calculated by assigning 1 point to each segmental PD. Combined score was calculated by adding the clot burden and PD score. All three scores were correlated with clinical and hemodynamic parameters that included New York Heart Association (NYHA) functional class, 6-minute walk distance (6MWT) in feet, forced expiratory volume in one second (FEV1), forced vital capacity (FVC), diffusing capacity of the lung for carbon monoxide (DLCO), pulmonary arterial pressure (PAP) [systolic PAP (sPAP), diastolic PAP (dPAP) and mean PAP (mPAP)], pulmonary vascular resistance (PVR), right atrial pressure, cardiac output, and cardiac index. Results: Clot burden score, PD score, and combined score all positively correlated with sPAP (0.25, 0.34, 0.34), PVR (0.27, 0.30, 0.34), and mPAP (0.28, 0.31, 0.36). There was no statistically significant correlation of clot burden score, PD score and combined score with 6MWT, % predicted 6MWT, FEV1, FEV1%, FVC, FVC%, DLCO% and NYHA functional class. Conclusions: DECT based scoring in CTEPH is feasible and correlates positively with sPAP, mPAP and PVR. Combined score has the highest magnitude of correlation.

Imaging algorithm for COVID-19: A practical approach.

The global pandemic of COVID-19 pneumonia caused by the novel coronavirus (SARS-CoV-2) has strained healthcare resources across the world with emerging challenges of mass testing, resource allocation and management. While reverse transcriptase-polymerase chain reaction (RT-PCR) test is the most commonly utilized test and considered the current gold standard for diagnosis, the role of chest imaging has been highlighted by several studies demonstrating high sensitivity of computed tomography (CT). Many have suggested using CT chest as a first-line screening tool for the diagnosis of COVID-19. However, with advancement of laboratory testing and challenges in obtaining a CT scan without significant risk to healthcare providers, the role of imaging in diagnosis has been questioned. Several imaging societies have released consensus statements and guidelines on utilizing imaging resources and optimal reporting. In this review, we highlight the current evidence on various modalities in thoracic imaging for the diagnosis of COVID-19 and describe an algorithm on how to use these resources in an optimal fashion in accordance with the guidelines and statements released by major imaging societies.

Role of Cardiac CT in Infective Endocarditis: Current Evidence, Opportunities, and Challenges.

Infective endocarditis (IE) can present with variable clinical and imaging findings and is associated with high morbidity and mortality. Substantial improvement of CT technology, most notably improved temporal and spatial resolution, has resulted in increased use of this modality in the evaluation of IE. The aim of this article is to review the potential role of cardiac CT in evaluating IE. Supplemental material is available for this article. © RSNA, 2021.

Incidental Thoracic Aortic Dilation on Chest Computed Tomography in Patients With Atrial Fibrillation.

Patients with atrial fibrillation (AF) have risk factors that predispose to thoracic aneurysmal disease (TAD) and atherosclerosis. In this study in patients with AF, we assessed the occurrence of incidental TAD and assessed if a validated predictive score used to predict AF, the CHARGE-AF score, was associated with greater aortic dimensions. We also assessed the prevalence of coronary calcification. We conducted a cross-sectional study of 1,000 consecutive patients with AF undergoing chest multidetector CT during evaluation for pulmonary vein isolation. A dilated aortic root or ascending aorta (AA, dimension/ body surface area >2.05 cm/m2) were found in 195 (20%). A total of 12 (1%) had significant aortic aneurysmal enlargement of > 5.0 cm. Advancing age, a bicuspid aortic valve, hypertension, and male gender were associated with increased aortic dimensions. Aortic root dimensions increased linearly (p < 0.001) and ascending aortic dimensions increased nonlinearly across CHARGE-AF deciles (p < 0.001). Nearly two-thirds (63%) had coronary calcification, 38% of whom were not on lipid-lowering therapy. In conclusion, in patients with AF undergoing gated chest CT, 1 in 5 had previously undetected TAD, with a small proportion having significantly aneurysmal dimensions approaching surgical thresholds. Risk factors previously established to increase the propensity to develop AF are also associated with increased TAD. These findings raise the need to consider a surveillance strategy for TAD in patients with AF, particularly in those with other risk factors for aortic disease. A high prevalence of coronary calcium was also detected, representing an opportunity to optimize statin therapy in patients with AF.

Thoracic hydatid disease: A radiologic review of unusual cases.

Hydatid disease or echinococcosis is a zoonotic parasitic disease. The lung is the second most commonly affected organ after the liver. Intra-thoracic and extra-pulmonary hydatid disease is uncommon and may involve the pleura, mediastinum, heart, diaphragm, and chest wall. Unusual locations or complications of thoracic hydatid disease may pose a diagnostic challenge. We present imaging findings of cases with unusual location and presentations of thoracic hydatid disease with emphasis on their clinical implications.

e-Cigarette or Vaping Product Use-Associated Lung Injury: Clinical, Radiologic, and Pathologic Findings of 15 Cases.

Since mid-2019, > 2,000 cases of e-cigarette or vaping product use-associated lung injury (EVALI) have been reported. Although initial reports suggested that this entity may be a form of inhalation-related lipoid pneumonia, subsequent studies indicate that EVALI represents various patterns of acute lung injury. Cases of EVALI continue to be reported, and public awareness of the epidemic is increasingly high. However, evidence surrounding optimal management of EVALI remains limited. In this case series, we report 15 cases of EVALI across a spectrum of severity, highlighting key radiologic, pathologic, and cytologic findings, and discuss management implications. In line with national findings, most patients with EVALI in the series vaped liquids containing tetrahydrocannabinol. Our imaging and pathologic findings support the notion that EVALI is a form of acute lung injury.

Hepatic hydatid disease complications: review of imaging findings and clinical implications.

Hydatid disease is a zoonotic parasitic disease. The liver is the most commonly affected organ, and hepatic hydatid disease complications are not uncommon. Hydatid cyst superinfection, intrabiliary rupture, and direct rupture into the thoracic or abdominal cavities are the frequently encountered complications. Other exceedingly rare complications include rupture of the cyst into hollow viscera, abdominal wall invasion, and hepatic vasculature-related complications such as portal vein thrombosis and Budd-Chiari syndrome. These complications have variable clinical presentations and imaging findings and require different medical and surgical managements. We aim to provide a spectrum of imaging findings of different common and uncommon complications of hepatic hydatid disease with emphasis on their clinical implications.

Noncompaction Cardiomyopathy: Case Presentation with Cardiac Magnetic Resonance Imaging Findings and Literature Review.

Left ventricular noncompaction cardiomyopathy is a very rare condition, yet believed to be often overlooked. It is thought to be caused by the developmental arrest in embryogenesis and characterized by an increase in the noncompacted, trabeculated myocardium adjacent to compacted myocardium in the left ventricular. The clinical presentations of this type of cardiomyopathy are of variable severity. Echocardiography used to be the diagnostic modality, but recent reports suggest that cardiac magnetic resonance imaging has higher sensitivity and specificity by showing a ratio of the noncompacted myocardium to compacted myocardium of >2.3.