Thoracic Imaging

Identification of Patients With Heart Failure From Test Bolus of Computed Tomography Angiography in Patients Undergoing Preoperative Evaluation for Transcatheter Aortic Valve Replacement Purpose: Identify a measurable parameter from test bolus of computed tomography angiography that can differentiate aortic stenosis patients with normal systolic function from those with heart failure and reduced ejection fraction (HFrEF). Materials and Methods: This retrospective study included patients (undergoing evaluation for transcatheter aortic valve replacement) who had retrospective electrocardiogram-gated cardiac computed tomography angiography using test bolus. The measured variables were time to peak contrast enhancement in the pulmonary artery (PAtime), in the ascending (AsAotime) and descending aorta (DsAotime). From these, the pulmonary transit time (PTT: difference between time to peak enhancement in the ascending aorta to peak enhancement in the main pulmonary artery), aortic transit time (ATT: difference between time to peak enhancement in the descending aorta to time to peak enhancement in the ascending aorta) and DsAotime−PAtime were also calculated. Biventricular volumes and function were calculated. The subjects were classified on the basis of ventricular ejection fractions: normal (EF>50%), midrange (EF 40% to 50%), and HF patients with reduced EF (EF<40%). Continuous variables were compared between all groups using ordinary 1-way analysis of variance, while sex was compared using the Fisher exact test. The unpaired t tests were used to compare between the normal and HF groups. Receiver operating characteristic analysis was used in predicting decreased cardiac function (EF<40% vs. EF>50%). Results: AsAotime and PTT were significant predictors of low biventricular EF when controlling for sex and body mass index (AsAotime: odds ratio=0.74 [95% confidence interval=0.61-0.91], P=0.005; PTT: odds ratio=0.64 95% confidence interval=0.46-0.88], P=0.006). A threshold of 23 seconds for AsAotime resulted in 72.1% sensitivity and 71.4% specificity, and 79.1% sensitivity and 64.3% specificity for DsAotime. Conclusions: The time to peak contrast enhancement from the test bolus images correlates with cardiac function. Decreased biventricular systolic dysfunction can be predicted if the time to peak contrast enhancement is >23 seconds in the ascending or descending aorta. The authors declare no conflicts of interest. Reprints: Abhishek Chaturvedi, MD, Department of Imaging Science, University of Rochester Medical Center, 601, Elmwood Avenue, Rochester, NY 14642 (e-mail: toabhic@gmail.com). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved

Computed Tomography–based Body Composition Analysis and Its Role in Lung Cancer Care Body composition analysis, also referred to as analytic morphomics, morphomics, or morphometry, describes the measurement of imaging biomarkers of body composition such as muscle and adipose tissue, most commonly on computed tomography (CT) images. A growing body of literature supports the use of such metrics derived from routinely acquired CT images for risk prediction in various patient populations, including those with lung cancer. Metrics include cross-sectional area and attenuation of skeletal muscle and subcutaneous, visceral, and intermuscular adipose tissue. The purpose of this review is to provide an overview of the concepts, definitions, assessment tools, segmentation techniques and associated pitfalls, interpretation of those measurements on chest and abdomen CT, and a discussion of reported outcomes associated with body composition metrics in patients with early-stage and advanced lung cancer. F.J.F. receives a related research seed grant from the Society of Thoracic Radiology. M.T. is supported by the Harvard Nutrition and Obesity Research Center NIH P30 DK040561. The remaining authors declare no conflicts of interest. Correspondence to: Florian J. Fintelmann, MD, 55 Fruit Street, FND-202, Boston, MA 02114 (e-mail: fintelmann@mgh.harvard.edu). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved

Proximal Interruption of the Pulmonary Artery and Unilateral Pulmonary Vein Atresia No abstract available

Proximal Interruption of the Pulmonary Artery No abstract available

Proximal Interruption of the Pulmonary Artery No abstract available

Cardiovascular Magnetic Resonance Imaging: Identifying the Effects of Cancer Therapy The era of modern oncology incorporates an ever-evolving personalized approach to hematological malignancies and solid tumors. As a result, patient survival rates have, in part, substantially improved, depending on the specific type of underlying malignancy. However, systemic therapies may come along with potential cardiotoxic effects resulting in heart failure with increased morbidity and mortality. Ultimately, patients may survive their malignancy but die as a result of cancer treatment. Cardiovascular magnetic resonance imaging has long been in use for the assessment of function and tissue characteristics in patients with various nonischemic cardiac diseases. Besides an introductory overview on the general definition of cardiotoxicity including potential underlying mechanisms, this review provides insight into the application of various cardiovascular magnetic resonance imaging techniques in the setting of cancer therapy–related cardiac and vascular toxicity. Early identification of cardiotoxic effects may allow for on-time therapy adjustment and/or cardioprotective measures to avoid subsequent long-term heart failure with increased mortality. B.J.W. receive research support from Siemens Healthineers, Speakers Honorarium Siemens Healthineers. The remaining authors declare no conflicts of interest. Correspondence to: Bernd J. Wintersperger, MD, EBCR, FAHA, Department of Medical Imaging, Toronto General Hospital, 1 PMB-273, 585 University Avenue, Toronto, ON, Canada M5G 2N2 (e-mail: bernd.wintersperger@uhn.ca). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved

Imaging-guided Percutaneous Biopsy of Nodules ≤1 cm: Study of Diagnostic Performance and Risk Factors Associated With Biopsy Failure Objective: Percutaneous biopsy of lung nodules is established as a safe procedure with high diagnostic yield and accuracy. Its role in the diagnosis of subcentimeter nodules is, however, less clear. The goal of this study was to evaluate diagnostic yield, accuracy, and safety of computed tomography (CT)-guided needle biopsy in the diagnosis of subcentimeter lung nodules. Material and Methods: A retrospective review of a prospectively maintained database over a 12-year period identified 133 eligible CT-guided needle biopsies of lesions ≤1 cm. Diagnostic yield and accuracy for the diagnosis of malignancy were calculated. Lesion features and procedure characteristics were assessed using univariate and multivariate logistic regression analysis to identify risk factors associated with biopsy failure and complications. Results: Biopsy specimens were adequate for diagnosis in 116/133(87%) cases; the diagnostic yield for malignant and benign lesions was 93% and 65%, respectively. Final benign diagnosis was the strongest independent risk factor for biopsy failure. In multivariate logistic regression, fine-needle aspiration was an independent risk factor for diagnostic failure. Core needle biopsy was an independent risk factor for pneumothorax, and core needle biopsy, number of passes, and age were independent risk factors for pneumothorax requiring tube drainage. Conclusions: CT-guided percutaneous needle biopsy had high diagnostic yield for the diagnosis of subcentimeter lung nodules with a similar complication rate to biopsy of larger lesions. Fine-needle aspiration may be an independent factor for diagnostic failure even for malignant lesions. The authors declare no conflicts of interest. Reprints: Carolina A. Souza, MD, PhD, Department of Radiology and Medical Imaging, University of Ottawa, The Ottawa Hospital, P.O. Box 232, General Campus Room 1466e, 501 Smyth Road, Ottawa, ON, Canada K1H 8L6 (e-mail: csouza@toh.ca). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved

Smoke: How to Differentiate Flow-related Artifacts From Pathology on Thoracic Computed Tomographic Angiography Nonuniform contrast opacification of vasculature is frequently encountered on thoracic computed tomographic angiography. The purpose of this pictorial essay is to discuss the appearance of, and factors underlying mixing artifacts, which we term “smoke.” We provide an approach to distinguish it from pathology including pulmonary embolism, aortic dissection, and thrombus. Smoke results from a combination of technical factors, abnormal physiology, or inflow of unopacified blood. Smoke produces ill-defined filling defects that may be confidently diagnosed in many cases if these fundamentals are applied. The authors declare no conflicts of interest. Correspondence to: Travis S. Henry, MD, Department of Radiology and Biomedical Imaging, University of California San Francisco, 505 Parnassus Avenue, M-396, San Francisco, CA 94143 (e-mail: travis.s.henry@gmail.com). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved

Cardiac Computed Tomography for Atrial Fibrillation Patients Undergoing Ablation: Implications for the Prediction of Early Recurrence Objective: The objective of this study was to correlate early recurrence of atrial fibrillation (AF) after ablation with noninvasive imaging using cardiac computed tomography (CT). Methods: CT image data of 260 patients who had undergone wide area circumferential ablation (WACA) between October 2005 and August 2010 as well as from 30 subjects in sinus rhythm without a history of AF (control group) were retrospectively analyzed. To evaluate early outcome of AF ablation, all AF patients underwent follow-up with a 30-day event monitor 3 to 4 months after ablation. In addition, a cardiac CT was also performed 3 to 4 months after ablation to exclude pulmonary vein (PV) stenosis. The presence of early AF was correlated with anatomic and functional PV and left atrial parameters, as assessed by cardiac CT. Results: A total of 70 patients (26.9%) were found to have early recurrence of AF. However, we found no association between PV or left atrial anatomic or functional parameters derived from cardiac imaging with early AF recurrence. Furthermore, no correlation (P>0.05) between AF recurrence and coronary artery stenosis, anatomic origin of the sinoatrial, or atrioventricular nodal arteries was observed. Finally, PV contraction did not predict AF recurrence. However, when comparing PV contraction in WACA patients with the control group, a significant (P<0.05) reduction in left superior PV and right superior PV contractility was found in patients after radiofreqency ablation. Conclusions: In our relatively large cohort, cardiac CT did not yield any anatomic or functional markers for the prediction of early AF recurrence after undergoing WACA. However, our data may provide insights into functional changes that occur following ablation procedures. U.J.S. receives institutional research support from Astellas, Bayer, GE, and Siemens Healthineers. U.J.S. received consulting fees/honoraria from Bayer, Guerbet, and Siemens. The remaining authors declare no conflicts of interest. Correspondence to: U. Joseph Schoepf, MD, Heart & Vascular Center, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Drive, Charleston, SC 29425-2260 (e-mail: schoepf@musc.edu). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved

Imaging Evaluation of Lung Transplantation Patients: A Time and Etiology-based Approach to High-resolution Computed Tomography Interpretation Lung transplantation is an established therapeutic option for patients with irreversible end-stage pulmonary disease limiting life expectancy and quality of life. Common indications for lung transplantation include chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, cystic fibrosis, pulmonary arterial hypertension, and alpha-1 antitrypsin deficiency. Complications of lung transplantation can be broadly divided etiologically into surgical, infectious, immunologic, or neoplastic. Moreover, specific complications often occur within a certain time interval following surgery, which can be broadly classified as early (<6 wk), intermediate (6 wk to 6 mo), and late (>6 mo). Thus, each group of complications can further be categorized on the basis of the time continuum from transplantation. Imaging, primarily by high-resolution computed tomography, plays a critical role in early diagnosis of complications after lung transplantation. Early recognition of complications by the radiologist, and initiation of therapy, contributes to improved morbidity and mortality. However, accurate diagnosis is only feasible if one has a thorough understanding of the major etiologic categories of complications and how they relate to the time course since transplantation. We review imaging manifestations of lung transplant complications via a framework that includes the following major etiologic categories: surgical; infectious; immunologic; and neoplastic; and the following time frames: surgery to 6 weeks; 6 weeks to 6 months; and beyond 6 months. We propose this approach as a logical, evidence-based algorithm to construct a narrow, optimal differential diagnosis of lung transplantation complications. The authors declare no conflicts of interest. Correspondence to: Chiemezie C. Amadi, MD, MA, Department of Radiology, Ohio State University, 395 W. 12th Avenue, 4th Floor, Columbus, OH 43210 (e-mail: chiemezie.amadi@osumc.edu). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved