Intracardiac shunt assessment using CT coronary angiography.

BACKGROUND: Detection of intracardiac shunts using CT Coronary Angiography (CTCA) is currently based on anatomical demonstration of defects. We assessed a novel technique using a standard CTCA test bolus in detecting shunts independent of anatomical assessment and to provide an estimate of Qp/Qs. METHODS: We retrospectively reviewed 51 CTCAs: twenty-one from patients with known simple left to right intracardiac shunts with contemporaneous functional assessment (using CMR) within 6 months, 20 controls with structurally normal hearts, and 10 patients with shunt repairs. From the dynamic acquisition of a test bolus, we measured mean Hounsfield Units (HU) in various anatomical structures. We created time/density curves from the test bolus data, and calculated disappearance time (DT) from the ascending aorta (deriving a Qp/Qs), peak ascending aortic HU, and mean coefficient of variation of the arterial curves, and compared these with the Qp/Qs from the respective CMR. RESULTS: Patients with intracardiac shunts had significantly higher test bolus derived Qp/Qs compared with both the controls, and the repaired shunt comparator group. There was a very strong agreement between the test bolus derived Qp/Qs, and Qp/Qs as measured by CMR (Intraclass correlation 0.89). Mean bias was 0.032 â€‹± â€‹0.341 (95% limits of agreement -0.64 to 0.70). Interobserver, and intraobserver agreement of the disappearance time was excellent (0.99, 0.99 (reader 1) and 1.00 (reader 2) respectively). CONCLUSION: In this proof-of-concept study, we demonstrate a novel technique to detect, and to estimate severity of left to right intracardiac shunts on routine Cardiac CT.

Prevalence of Thrombotic Complications in ICU-Treated Patients With Coronavirus Disease 2019 Detected With Systematic CT Scanning.

OBJECTIVES: Severe coronavirus disease 2019 is associated with an extensive pneumonitis and frequent coagulopathy. We sought the true prevalence of thrombotic complications in critically ill patients with severe coronavirus disease 2019 on the ICU, with or without extracorporeal membrane oxygenation. DESIGN: We undertook a single-center, retrospective analysis of 72 critically ill patients with coronavirus disease 2019-associated acute respiratory distress syndrome admitted to ICU. CT angiography of the thorax, abdomen, and pelvis were performed at admission as per routine institution protocols, with further imaging as clinically indicated. The prevalence of thrombotic complications and the relationship with coagulation parameters, other biomarkers, and survival were evaluated. SETTING: Coronavirus disease 2019 ICUs at a specialist cardiorespiratory center. PATIENTS: Seventy-two consecutive patients with coronavirus disease 2019 admitted to ICU during the study period (March 19, 2020, to June 23, 2020). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: All but one patient received thromboprophylaxis or therapeutic anticoagulation. Among 72 patients (male:female = 74%; mean age: 52 ± 10; 35 on extracorporeal membrane oxygenation), there were 54 thrombotic complications in 42 patients (58%), comprising 34 pulmonary arterial (47%), 15 peripheral venous (21%), and five (7%) systemic arterial thromboses/end-organ embolic complications. In those with pulmonary arterial thromboses, 93% were identified incidentally on first screening CT with only 7% suspected clinically. Biomarkers of coagulation (e.g., d-dimer, fibrinogen level, and activated partial thromboplastin time) or inflammation (WBC count, C-reactive protein) did not discriminate between patients with or without thrombotic complications. Fifty-one patients (76%) survived to discharge; 17 (24%) patients died. Mortality was significantly greater in patients with detectable thrombus (33% vs 10%; p = 0.022). CONCLUSIONS: There is a high prevalence of thrombotic complications, mainly pulmonary, among coronavirus disease 2019 patients admitted to ICU, despite anticoagulation. Detection of thrombus was usually incidental, not predicted by coagulation or inflammatory biomarkers, and associated with increased risk of death. Systematic CT imaging at admission should be considered in all coronavirus disease 2019 patients requiring ICU.

Interstitial Lung Disease in Children Made Easier Well, Almost.

Interstitial lung disease (ILD) in pediatric patients is different from that in adults, with a vast array of pathologic conditions unique to childhood, varied modes of presentation, and a different range of radiologic appearances. Although rare, childhood ILD (chILD) is associated with significant morbidity and mortality, most notably in conditions of disordered surfactant function, with respiratory failure in 100% of neonates with surfactant protein B dysfunction and 100% mortality without lung transplantation. The authors present a summary of lung development and anatomy, followed by an organized approach, using the structure and nomenclature of the 2013 update to the chILD Research Network classification system, to aid radiologic diagnosis of chILD. Index radiologic cases with contemporaneous histopathologic findings illustrate a summary of recent imaging studies covering the full spectrum of chILD. chILD is best grouped by age at presentation from infancy (diffuse developmental disorders, lung growth abnormalities, specific conditions of unknown origin, surfactant dysfunction mutations) to later childhood (disorders of the normal host, disorders related to systemic disease processes, disorders related to immunocompromise). Appreciation of the temporal division of chILD into infant and later childhood onset, along with a sound understanding of pulmonary organogenesis and surfactant homeostasis, will aid in providing useful insight into this important group of pediatric conditions. Application of secondary lobular anatomy to interpretation of thin-section computed tomographic images is pivotal to understanding patterns of ILD and will aid in selecting and narrowing a differential diagnosis. ©RSNA, 2017.