NASCI case of the month: a case of anomalous right coronary artery arising from the pulmonary artery.

Coronary artery anomalies are rare but potentially fatal abnormalities with occasional striking imaging findings radiologists should recognize.

Reduced Chest Computed Tomography Scan Length for Patients Positive for Coronavirus Disease 2019: Dose Reduction and Impact on Diagnostic Utility.

METHODS: This study used the Personalized Rapid Estimation of Dose in CT (PREDICT) tool to estimate patient-specific organ doses from CT image data. The PREDICT is a research tool that combines a linear Boltzmann transport equation solver for radiation dose map generation with deep learning algorithms for organ contouring. Computed tomography images from 74 subjects in the Medical Imaging Data Resource Center-RSNA International COVID-19 Open Radiology Database data set (chest CT of adult patients positive for COVID-19), which included expert annotations including "infectious opacities," were analyzed. First, the full z-scan length of the CT image data set was evaluated. Next, the z-scan length was reduced from the left hemidiaphragm to the top of the aortic arch. Generic dose reduction based on dose length product (DLP) and patient-specific organ dose reductions were calculated. The percentage of infectious opacities excluded from the reduced z-scan length was used to quantify the effect on diagnostic utility. RESULTS: Generic dose reduction, based on DLP, was 69%. The organ dose reduction ranged from approximately equal to 18% (breasts) to approximately equal to 64% (bone surface and bone marrow). On average, 12.4% of the infectious opacities were not included in the reduced z-coverage, per patient, of which 5.1% were above the top of the arch and 7.5% below the left hemidiaphragm. CONCLUSIONS: Limiting z-scan length of chest CTs reduced radiation dose without significantly compromising diagnostic utility in COVID-19 patients. The PREDICT demonstrated that patient-specific organ dose reductions varied from generic dose reduction based on DLP.

Diastolic Cardiac Function by MRI-Imaging Capabilities and Clinical Applications.

Most cardiac studies focus on evaluating left ventricular (LV) systolic function. However, the assessment of diastolic cardiac function is becoming more appreciated, especially with the increasing prevalence of pathologies associated with diastolic dysfunction like heart failure with preserved ejection fraction (HFpEF). Diastolic dysfunction is an indication of abnormal mechanical properties of the myocardium, characterized by slow or delayed myocardial relaxation, abnormal LV distensibility, and/or impaired LV filling. Diastolic dysfunction has been shown to be associated with age and other cardiovascular risk factors such as hypertension and diabetes mellitus. In this context, cardiac magnetic resonance imaging (MRI) has the capability for differentiating between normal and abnormal myocardial relaxation patterns, and therefore offers the prospect of early detection of diastolic dysfunction. Although diastolic cardiac function can be assessed from the ratio between early and atrial filling peaks (E/A ratio), measuring different parameters of heart contractility during diastole allows for evaluating spatial and temporal patterns of cardiac function with the potential for illustrating subtle changes related to age, gender, or other differences among different patient populations. In this article, we review different MRI techniques for evaluating diastolic function along with clinical applications and findings in different heart diseases.

Platforms to test the temporospatial capabilities of carrier systems in delivering growth factors to benefit vascular bioengineering.

In this study we produced a set of in vitro culture platforms to model vascular cell responses to growth factors and factor delivery vehicles. Two of the systems (whole vessel and whole lung vascular development) were supported by microfluidic systems facilitating media circulation and waste removal. We assessed vascular endothelial growth factor (VEGF) delivery by Pluronic F-127 hydrogel, 30 nm pore-sized microparticles (MPs), 60 nm pore-sized MP or a 50/50 mixture of 30 and 60 nm pore-sized MP. VEGF was delivered to porcine acellular lung vascular scaffolds (2.5 cm2 square pieces or whole 3D segments of acellular blood vessels) as well as whole acellular lung scaffolds. Scaffold-cell attachment was examined as was vascular tissue formation. We showed that a 50/50 mixture of 30 and 60 nm pore-sized silicon wafer MPs allowed for long-term release of VEGF within the scaffold vasculature and supported vascular endothelial tissue development during in vitro culture.

Value CMR: Towards a Comprehensive, Rapid, Cost-Effective Cardiovascular Magnetic Resonance Imaging.

Cardiac magnetic resonance imaging (CMR) is considered the gold standard for measuring cardiac function. Further, in a single CMR exam, information about cardiac structure, tissue composition, and blood flow could be obtained. Nevertheless, CMR is underutilized due to long scanning times, the need for multiple breath-holds, use of a contrast agent, and relatively high cost. In this work, we propose a rapid, comprehensive, contrast-free CMR exam that does not require repeated breath-holds, based on recent developments in imaging sequences. Time-consuming conventional sequences have been replaced by advanced sequences in the proposed CMR exam. Specifically, conventional 2D cine and phase-contrast (PC) sequences have been replaced by optimized 3D-cine and 4D-flow sequences, respectively. Furthermore, conventional myocardial tagging has been replaced by fast strain-encoding (SENC) imaging. Finally, T1 and T2 mapping sequences are included in the proposed exam, which allows for myocardial tissue characterization. The proposed rapid exam has been tested in vivo. The proposed exam reduced the scan time from >1 hour with conventional sequences to <20 minutes. Corresponding cardiovascular measurements from the proposed rapid CMR exam showed good agreement with those from conventional sequences and showed that they can differentiate between healthy volunteers and patients. Compared to 2D cine imaging that requires 12-16 separate breath-holds, the implemented 3D-cine sequence allows for whole heart coverage in 1-2 breath-holds. The 4D-flow sequence allows for whole-chest coverage in less than 10 minutes. Finally, SENC imaging reduces scan time to only one slice per heartbeat. In conclusion, the proposed rapid, contrast-free, and comprehensive cardiovascular exam does not require repeated breath-holds or to be supervised by a cardiac imager. These improvements make it tolerable by patients and would help improve cost effectiveness of CMR and increase its adoption in clinical practice.

Cardiovascular magnetic resonance in women with cardiovascular disease: position statement from the Society for Cardiovascular Magnetic Resonance (SCMR).

This document is a position statement from the Society for Cardiovascular Magnetic Resonance (SCMR) on recommendations for clinical utilization of cardiovascular magnetic resonance (CMR) in women with cardiovascular disease. The document was prepared by the SCMR Consensus Group on CMR Imaging for Female Patients with Cardiovascular Disease and endorsed by the SCMR Publications Committee and SCMR Executive Committee. The goals of this document are to (1) guide the informed selection of cardiovascular imaging methods, (2) inform clinical decision-making, (3) educate stakeholders on the advantages of CMR in specific clinical scenarios, and (4) empower patients with clinical evidence to participate in their clinical care. The statements of clinical utility presented in the current document pertain to the following clinical scenarios: acute coronary syndrome, stable ischemic heart disease, peripartum cardiomyopathy, cancer therapy-related cardiac dysfunction, aortic syndrome and congenital heart disease in pregnancy, bicuspid aortic valve and aortopathies, systemic rheumatic diseases and collagen vascular disorders, and cardiomyopathy-causing mutations. The authors cite published evidence when available and provide expert consensus otherwise. Most of the evidence available pertains to translational studies involving subjects of both sexes. However, the authors have prioritized review of data obtained from female patients, and direct comparison of CMR between women and men. This position statement does not consider CMR accessibility or availability of local expertise, but instead highlights the optimal utilization of CMR in women with known or suspected cardiovascular disease. Finally, the ultimate goal of this position statement is to improve the health of female patients with cardiovascular disease by providing specific recommendations on the use of CMR.

Validation of left ventricular volume and ejection fraction measurements by high-definition blood flow imaging: Comparisons with cardiac magnetic resonance imaging and contrast echocardiography.

BACKGROUND: We recently reported the efficacy of High-definition blood flow imaging (HDI) in the assessment of left ventricular (LV) function and demonstrated that the results are comparable to those obtained by contrast echocardiography (CE). The present study validates HDI in measurements of LV volumes and ejection fraction (EF) by simultaneous comparisons with CE and cardiac magnetic resonance imaging (CMR). METHODS: Eighteen patients (age range 25-79 years) with limited echocardiographic images had measurements of LV end-diastolic volume (EDV, mL), end-systolic volume (ESV, mL), and EF (%) by HDI, CE, and CMR. RESULTS: Using the three techniques, measurements of EDV, ESV, and EF correlated well with correlation coefficients (r) ranging from .91 to .98 in comparisons between HDI and CMR, and .89 to .97 in comparisons between CE and CMR. The limits of agreement for the inter-methods comparisons by Bland-Altman analysis (mean ± 1.96 SD) between HDI and CMR were 4.92 ± 16.87% for EF, 21.53 ± 32.18 mL for EDV, and 10.69 ± 36.12 mL for ESV, between CE and CMR, the agreement limits were 2.48 ± 18.52% (LVEF), 24.58 ± 47.41 mL (EDV), and 14.09 ± 43.55 mL (ESV). CONCLUSIONS: Measurements of LV volumes and EF by HDI and CE correlated well with CMR. Using CMR as the gold standard, the agreements in measurements of LV volumes were superior for HDI compared to CE. In measurements of EF, CE showed less mean difference when compared to HDI. HDI measurements compared well with those obtained by CMR.

Cardiovascular disease in women: insights from magnetic resonance imaging.

The presentation and identification of cardiovascular disease in women pose unique diagnostic challenges compared to men, and underrecognized conditions in this patient population may lead to clinical mismanagement.This article reviews the sex differences in cardiovascular disease, explores the diagnostic and prognostic role of cardiovascular magnetic resonance (CMR) in the spectrum of cardiovascular disorders in women, and proposes the added value of CMR compared to other imaging modalities. In addition, this article specifically reviews the role of CMR in cardiovascular diseases occurring more frequently or exclusively in female patients, including Takotsubo cardiomyopathy, connective tissue disorders, primary pulmonary arterial hypertension and peripartum cardiomyopathy. Gaps in knowledge and opportunities for further investigation of sex-specific cardiovascular differences by CMR are also highlighted.

Uterineintravenous leiomyomatosis with cardiac involvement.

Intravenous leiomyomatosis is a histologically benign smooth muscle tumor that arises either by direct extension of a uterine leiomyoma into the adjacent veins or by vascular intimal smooth muscle proliferation. Herein, we report the case of a 60-year-old female who was noted to have suspected cardiac mass on elective echocardiography done electively for abnormal electrocardiographic findings. Computed tomography and cardiac magnetic resonance indicated the presence of an intravenous leiomyoma originating from the uterus and extending to the inferior vena cava and right atrium. The patient was managed with a single-stage surgery involving cardiopulmonary bypass and excision of the right atrial mass, excision of the inferior vena cava tumor thrombus, and total abdominal hysterectomy and bilateral salpingo-oophorectomy.

Multidetector Computed Tomography (MDCT) Angiography in the Pre-Procedural Assessment of Patients Undergoing Transcatheter Aortic Valve Replacement.

Transcatheter aortic valve replacement (TAVR) initially emerged as an alternative option to surgical aortic valve replacement (SAVR) for patients with severe aortic stenosis who were considered either inoperable or high-risk for surgery. However, since its advent the role of TAVR has been continuously evolving on the basis of clinical trials which showed that TAVR is non-inferior to SAVR in patients with moderate as well as low-risk for surgery. Because of recent technological advances, multidetector computer tomography (MDCT) is inherently suitable for the pre-procedural assessment of patients being considered for TAVR within a very short imaging time, MDCT can measure the diameter of the aortic annulus, provide detailed information regarding the status of the entire thoracoabdominal aorta, and assess the caliber of the peripheral vasculature used for transcatheter heart valve delivery. This information helps interventionists make optimal pre-procedural decisions and avoid complications. To familiarize non-imaging specialists with the role of MDCT in TAVR, we provide a concise overview of our approach to using this modality for the pre-procedural assessment of TAVR candidates.

Left Ventricular Noncompaction in a Child with Turner Syndrome.

Congenital heart disease (CHD) may cause a significant comorbidity in patients with Turner syndrome. The commonly reported CHD in these patients includes bicuspid aortic valve and coarctation of the aorta. Left ventricular noncompaction (LVNC) is a rare form of cardiomyopathy that has been reported in literature only three times in adult patients with Turner syndrome. We report the first case of a 6-year-old asymptomatic female with Turner syndrome who was referred for cardiac evaluation after her Turner syndrome diagnosis. Echocardiogram was suspicious for LVNC, which was confirmed on cardiac magnetic resonance imaging.

Production and transplantation of bioengineered lung into a large-animal model.

The inability to produce perfusable microvasculature networks capable of supporting tissue survival and of withstanding physiological pressures without leakage is a fundamental problem facing the field of tissue engineering. Microvasculature is critically important for production of bioengineered lung (BEL), which requires systemic circulation to support tissue survival and coordination of circulatory and respiratory systems to ensure proper gas exchange. To advance our understanding of vascularization after bioengineered organ transplantation, we produced and transplanted BEL without creation of a pulmonary artery anastomosis in a porcine model. A single pneumonectomy, performed 1 month before BEL implantation, provided the source of autologous cells used to bioengineer the organ on an acellular lung scaffold. During 30 days of bioreactor culture, we facilitated systemic vessel development using growth factor-loaded microparticles. We evaluated recipient survival, autograft (BEL) vascular and parenchymal tissue development, graft rejection, and microbiome reestablishment in autografted animals 10 hours, 2 weeks, 1 month, and 2 months after transplant. BEL became well vascularized as early as 2 weeks after transplant, and formation of alveolar tissue was observed in all animals (n = 4). There was no indication of transplant rejection. BEL continued to develop after transplant and did not require addition of exogenous growth factors to drive cell proliferation or lung and vascular tissue development. The sterile BEL was seeded and colonized by the bacterial community of the native lung.

Mixing It Up: Coadministration of tPA/DNase in Complicated Parapneumonic Pleural Effusions and Empyema.

BACKGROUND: A recent randomized controlled trial showed 12 serial doses of tissue plasminogen activator (tPA) and deoxyribonuclease (DNase) is safe and effective in managing complicated parapneumonic pleural effusions and empyema (CPEE). However, this regimen is laborious, requiring trained personnel to open/close the chest tube 8 times daily for 3 days. We present our observational data using a simplified regimen of coadministered tPA/DNase. MATERIALS AND METHODS: This is a retrospective observational study of patients who received coadministered tPA/DNase for CPEE from January 2012 to April 2015 at the University of Texas Medical Branch. Patient demographics, pleural fluid, radiologic and treatment characteristics, and outcomes were collected. Data are presented as proportions and percentages. Our primary outcome was successful treatment without need of surgery and discharge home alive. Secondary outcomes were dose and length of treatment and hospital stay, treatment complications, and 90-day mortality. RESULTS: The study included 39 patients. All pleural effusions were loculated, 59% macroscopically purulent, 50% had a positive organism in Gram stain, and 40% were culture positive. A median of 6 (interquartile range, 3.5 to 6) doses were coadministered mainly via small bore chest tube (≤14 Fr in 79%) with a median of 14.5 (interquartile range, 9.5 to 21.5) hospital days. Overall, 85% were successfully treated without need for surgery. Treatment failures occurred in 15%: 3/39 (7%) received surgery; 3/39 (7%) died. Only 1 (2.5%) complication of hemorrhagic pleural effusion resolved after discontinuation of intrapleural treatment. CONCLUSIONS: Our study shows intrapleural coadministration of tPA/DNase was effective and safe in management of CPEE.

Value of Cardiac Magnetic Resonance Imaging in Patients With Failed Ablation Procedures for Ventricular Tachycardia.

BACKGROUND: Ventricular tachycardia (VT) in patients with cardiomyopathy originates in scar tissue. Intramural or epicardial scar may result in ineffective ablation if mapping and ablation are limited to the endocardium. The purpose of this study was to investigate whether preprocedural magnetic resonance imaging (MRI) is beneficial in patients with failed endocardial VT ablations in determining an appropriate ablation strategy. METHODS AND RESULTS: A cardiac MRI was performed in 20 patients with a failed ablation procedure and cardiomyopathy (nonischemic n = 12, ischemic n = 8). A subsequent ablation strategy was determined by a delayed enhanced MRI (DE-MRI) and an epicardial subxyphoid access was planned only in patients with epicardial or intramural free-wall scar. MRIs were performed in all patients with or without an implanted cardioverter defibrillator (ICD). The location of scar tissue in the MRI predicted the origin of VT in all patients. In 9/20 patients an epicardial procedure was performed based on the result of the MRI. An endocardial procedure was performed in the remaining 11 patients who had either endocardial or septal scarring and one patient in whom the MRI only showed artifact. Five patients remained inducible postablation and four patients had VT recurrence within a follow-up period of 17 ± 22 months. All of the latter patients had an intramural scar pattern. CONCLUSIONS: Imaging with DE-MRI prior to VT ablation in patients with previously failed endocardial ablation procedures is beneficial in identifying an ablation strategy, helps to focus on an area of interest intraprocedurally, and provides valuable outcomes information.

Left atrial function and maximum volume as determined by MDCT are independently associated with atrial fibrillation.

RATIONALE AND OBJECTIVES: To assess whether left atrial (LA) volume, function, and diameter as determined by multidetector computed tomography (MDCT) are associated with the presence and chronicity of atrial fibrillation (AF). MATERIALS AND METHODS: A total of 232 subjects, 156 with AF (43 with chronic and 113 with paroxysmal) and 76 normal subjects, formed the study population. AF subjects underwent MDCT of the pulmonary veins and LA, and normal subjects underwent coronary computed tomography (CT), on which LA volume, function, and diameter were measured. Associations between each MDCT LA parameter and presence and chronicity of AF were assessed using logistic regression analysis. RESULTS: The indexed LA maximum volume (odds ratio [OR]=2.42; 95% confidence interval [CI], 1.43-4.08; P=.0009) was significantly associated with chronicity and presence of AF (OR=1.06; 95% CI, 1.03-1.10; P=.0003) after adjustment for traditional risk factors. The LA function was associated with presence of AF (OR=0.93; 95% CI, 0.89-0.97; P=.0005), but not with AF chronicity (OR=1.12; 95% CI, 0.93-1.33; P=.21). CONCLUSIONS: Decreased LA function is associated with presence of AF, and increased LA maximum volume is associated with presence and chronicity of AF, independent of traditional risk factors.

Radiation risk of lung cancer screening.

Lung cancer screening with low dose computed tomography (CT) is the only method ever proven to reduce lung cancer-specific mortality in high-risk current and former cigarette smokers. Radiation exposure from annual screening CT examinations and subsequent CT and nuclear medicine testing to further evaluate positive screening CTs is sometimes raised as a reason to avoid screening and is often misunderstood. With all testing, there are potential benefits and risks. As we sit on the brink of widespread adoption of lung cancer screening CT, we aim to explain why the risks associated with radiation exposure from lung cancer screening are very low and should not be used to avoid screening or dissuade individuals who qualify for screening CT to participate in a lung cancer screening program.

Chest CT incidentalomas: thyroid lesions, enlarged mediastinal lymph nodes, and lung nodules.

A computed tomography (CT) incidentaloma is an incidentally detected and previously unsuspected finding or abnormality that is not related to the indication for obtaining the CT examination. The aim of this article is to review the frequency of incidentalomas on chest CT scans, discuss the potential clinical significance of the findings, and suggest guidelines for reporting, further evaluation, and follow-up, with particular focus on thyroid lesions, enlarged mediastinal lymph nodes and lung nodules.

Cardiovascular MR imaging of conotruncal anomalies.

Conotruncal anomalies are congenital heart defects that result from abnormal formation and septation of the outflow tracts of the heart and great vessels. The major conotruncal anomalies include tetralogy of Fallot, transposition of the great arteries, double-outlet right ventricle, truncus arteriosus, and interrupted aortic arch. Cardiovascular magnetic resonance (MR) imaging is an important modality for the evaluation of patients with these defects. Major advances in cardiovascular MR imaging equipment and techniques allow precise delineation of the cardiovascular anatomy and accurate quantitative assessment of ventricular function and blood flow. The data provided by cardiovascular MR imaging are useful for treatment planning and posttreatment monitoring, supplement information obtained with echocardiography, and in many cases obviate cardiac catheterization.

Computer-aided diagnosis of lung nodules on CT scans: ROC study of its effect on radiologists' performance.

RATIONALE AND OBJECTIVES: The aim of this study was to evaluate the effect of computer-aided diagnosis (CAD) on radiologists' estimates of the likelihood of malignancy of lung nodules on computed tomographic (CT) imaging. METHODS AND MATERIALS: A total of 256 lung nodules (124 malignant, 132 benign) were retrospectively collected from the thoracic CT scans of 152 patients. An automated CAD system was developed to characterize and provide malignancy ratings for lung nodules on CT volumetric images. An observer study was conducted using receiver-operating characteristic analysis to evaluate the effect of CAD on radiologists' characterization of lung nodules. Six fellowship-trained thoracic radiologists served as readers. The readers rated the likelihood of malignancy on a scale of 0% to 100% and recommended appropriate action first without CAD and then with CAD. The observer ratings were analyzed using the Dorfman-Berbaum-Metz multireader, multicase method. RESULTS: The CAD system achieved a test area under the receiver-operating characteristic curve (A(z)) of 0.857 +/- 0.023 using the perimeter, two nodule radii measures, two texture features, and two gradient field features. All six radiologists obtained improved performance with CAD. The average A(z) of the radiologists improved significantly (P < .01) from 0.833 (range, 0.817-0.847) to 0.853 (range, 0.834-0.887). CONCLUSION: CAD has the potential to increase radiologists' accuracy in assessing the likelihood of malignancy of lung nodules on CT imaging.