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T1/T2 parametric mapping may reveal patterns of elevation ("hotspots") in myocardial diseases, such as rejection in orthotopic heart transplant (OHT) patients. This study aimed to evaluate the diagnostic accuracy of free-breathing (FB) multi-parametric SAturation recovery single-SHot Acquisition (mSASHA) T1/T2 mapping in identifying hotspots present on conventional Breath-held Modified Look-Locker Inversion recovery (BH MOLLI) T1 and T2-prepared balanced steady-state free-precession (BH T2p-bSSFP) maps in pediatric OHT patients. Pediatric OHT patients underwent noncontrast 1.5T CMR with BH MOLLI T1 and T2p-bSSFP and prototype FB mSASHA T1/T2 mapping in 8 short-axis slices. FB and BH T1/T2 hotspots were segmented using semi-automated thresholding (ITK-SNAP) and their 3D coordinate locations were collected (3-Matic, Materialise, Leuven, Belgium). Receiver operator characteristic curve analysis and measures of central tendency were utilized. 40 imaging datasets from 23 pediatric OHT patients were obtained. FB mSASHA yielded a sensitivity of 82.8% for T1 and 80% for T2 maps when compared to the standard BH MOLLI, as well as 100% specificity for both T1 and T2 maps. When identified on both FB and BH maps, hotspots overlapped in all cases, with an average long axis offset between FB and BH hotspot centers of 5.8 mm (IQR 3.5-8.2) on T1 and 5.9 mm (IQR 3.5-8.2) on T2 maps. FB mSASHA T1/T2 maps can identify hotspots present on conventional BH T1/T2 maps in pediatric patients with OHT, with high sensitivity, specificity, and overlap in 3D space. Free-breathing mapping may improve patient comfort and facilitate OHT assessment in younger patient populations.
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Trasplante de Corazón , Imagen por Resonancia Magnética , Humanos , Niño , Imagen por Resonancia Magnética/métodos , Valor Predictivo de las Pruebas , Corazón , Trasplante de Corazón/efectos adversos , Contencion de la Respiración , Reproducibilidad de los Resultados , Fantasmas de ImagenRESUMEN
BACKGROUND: Lifetime radiation exposure for paediatric orthotopic heart transplant (OHT) patients is significant with cardiac catheterisation as the dominant source. Interventional cardiac magnetic resonance is utilised to obtain simultaneous, radiation-free haemodynamics and flow/function measurements. We sought to compare invasive haemodynamic measurements and radiation exposure in traditional cardiac catheterisation, to comprehensive interventional cardiac magnetic resonance. METHODS: Twenty-eight OHT patients who underwent 67 interventional cardiac magnetic resonance procedures at Children's National Hospital were identified. Both invasive oximetry with peripheral oxygen saturation (Fick) and cardiac magnetic resonance phase contrast measurements of pulmonary and systemic blood flow were performed. Systemic and pulmonary blood flow from the two modalities was compared using Bland-Altman, concordance analysis, and inter-reader correlation. A mixed model was implemented to account for confounding variables and repeat encounters. Radiation dosage data were collected for a contemporaneous cohort of orthotopic heart transplant patients undergoing standard, X-ray-guided catheterisation. RESULTS: Simultaneous cardiac magnetic resonance and Fick have poor agreement in our study based on Lin's correlation coefficient of 0.68 and 0.73 for pulmonary and systemic blood flow, respectively. Bland-Altman analysis demonstrated a consistent over estimation of cardiac magnetic resonance cardiac output by Fick. The average indexed dose area product for patients undergoing haemodynamics with endomyocardial biopsy was 0.73 (SD ±0.6) Gy*m2/kg. With coronary angiography added, the indexed dose area product was 14.6 (SD ± 7.8) Gy*m2/kg. CONCLUSIONS: Cardiac magnetic resonancemeasurements of cardiac output/index in paediatric orthotopic heart transplant patients have poor concordance with Fick estimates; however, cardiac magnetic resonance has good internal validity and inter-reader reliability. Radiation doses are small for haemodynamics with biopsy and increase exponentially with angiography, identifying a new target for cardiac magnetic resonance imaging.
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Trasplante de Corazón , Imagen por Resonancia Magnética , Niño , Humanos , Reproducibilidad de los Resultados , Cateterismo Cardíaco , Oximetría/métodos , Gasto Cardíaco/fisiología , Espectroscopía de Resonancia MagnéticaRESUMEN
Efficient and stable lead-free halide double perovskites (DPs) have attracted great attention for the future generation of electronic devices. Herein, we have developed a doping approach to incorporate Fe3+ ions into the Cs2NaBiCl6 crystal unit and reveal a crystallographic and optoelectronic study of the Cs2NaBi1-xFexCl6 double perovskite. We report a simple solid-state mechanochemical method that has a solvent-free, one-step, green chemistry approach for the synthesis of Cs2NaBi1-xFexCl6 phosphor. The analysis of powder X-ray diffraction (XRD) data determines the contraction of the lattice due to the incorporation of Fe3+ cations, and this effect is well supported by X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), Raman spectroscopy, and solid-state nuclear magnetic resonance spectroscopy (ss-NMR). The band gap is reduced with increasing Fe content owing to the strong overlap of the Fe-3d orbitals with Cl-3p orbitals and shift of the valence band maxima (VBM) toward higher energies, as confirmed by ultraviolet photoelectron spectroscopy (UPS) and density functional theory (DFT) analyses. Photoluminescence (PL) studies of Cs2NaBi1-xFexCl6 phosphors exhibit a large Stokes shift, broadband emission, and increased PL intensity more than ten times for 15% of Fe content phosphor with enhancement in the average decay lifetimes (up to 38 ns) compared to pristine Cs2NaBiCl6 DP. These results indicate that the transition of dark self-trapping of excitons (STEs) into bright STEs enhances yellow emission. XRD, UV, and thermo-gravimetric analysis (TGA) confirmed that the Cs2NaB1-xFexCl6 DPs have good structural and thermal stabilities. Our findings indicate that the doping of Fe3+ cations into the Cs2NaBiCl6 lattice is a constructive strategy to enhance significantly the optoelectronic properties of these phosphors.
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BACKGROUND: Cardiovascular magnetic resonance (CMR) allows for time-resolved three-dimensional phase-contrast (4D Flow) analysis of congenital heart disease (CHD). Higher spatial resolution in small infants requires thinner slices, which can degrade the signal. Particularly in infants, the choice of contrast agent (ferumoxytol vs. gadolinium) may influence 4D Flow CMR accuracy. Thus, we investigated the accuracy of 4D Flow CMR measurements compared to gold standard 2D flow phase contrast (PC) measurements in ferumoxytol vs. gadolinium-enhanced CMR of small CHD patients with shunt lesions. METHODS: This was a retrospective study consisting of CMR studies from complex CHD patients less than 20 kg who had ferumoxytol or gadolinium-enhanced 4D Flow and standard two-dimensional phase contrast (2D-PC) flow collected. 4D Flow clinical software (Arterys) was used to measure flow in great vessels, systemic veins, and pulmonary veins. 4D Flow accuracy was defined as percent difference or correlation against conventional measurements (2D-PC) from the same vessels. Subgroup analysis was performed on two-ventricular vs single-ventricular CHD, arterial vs venous flow, as well as low flows (defined as < 1.5 L/min) in 1V CHD. RESULTS: Twenty-one ferumoxytol-enhanced and 23 gadolinium-enhanced CMR studies were included, with no difference in age (2.1 ± 1.6 vs. 2.3 ± 1.9 years, p = 0.70), patient body surface area (0.50 ± 0.2 vs. 0.52 ± 0.2 m2, p = 0.67), or vessel diameter (11.4 ± 5.2 vs. 12.4 ± 5.6 mm, p = 0.22). Ten CMR studies with single ventricular CHD were included. Overall, ferumoxytol-enhanced 4D flow CMR measurements demonstrated less percent difference to 2D-PC when compared to gadolinium-enhanced 4D Flow CMR studies. In subgroup analyses of arterial vs. venous flows (high velocity vs. low velocity) and low flow in single ventricle CHD, ferumoxytol-enhanced 4D Flow CMR measurements had stronger correlation to 2D-PC CMR. The contrast-to-noise ratio (CNR) in ferumoxytol-enhanced studies was higher than the CNR in gadolinium-enhanced studies. CONCLUSIONS: Ferumoxytol-enhanced 4D Flow CMR has improved accuracy when compared to gadolinium 4D Flow CMR, particularly for infants with small vessels in CHD.
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Gadolinio , Cardiopatías Congénitas , Niño , Lactante , Humanos , Óxido Ferrosoférrico , Estudios Retrospectivos , Velocidad del Flujo Sanguíneo , Valor Predictivo de las Pruebas , Cardiopatías Congénitas/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Ventrículos Cardíacos , Espectroscopía de Resonancia Magnética , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: Cardiovascular magnetic resonance (CMR) is emerging as an important tool for cardiac allograft assessment. Native T1 mapping may add value in identifying rejection and in assessing graft dysfunction and myocardial fibrosis burden. We hypothesized that CMR native T1 values and features of textural analysis of T1 maps would identify acute rejection, and in a secondary analysis, correlate with markers of graft dysfunction, and with fibrosis percentage from endomyocardial biopsy (EMB). METHODS: Fifty cases with simultaneous EMB, right heart catheterization, and 1.5 T CMR with breath-held T1 mapping via modified Look-Locker inversion recovery (MOLLI) in 8 short-axis slices and subsequent quantification of mean and peak native T1 values, were performed on 24 pediatric subjects. A single mid-ventricular slice was used for image texture analysis using nine gray-level co-occurrence matrix features. Digital quantification of Masson trichrome stained EMB samples established degree of fibrosis. Markers of graft dysfunction, including serum brain natriuretic peptide levels and hemodynamic measurements from echocardiography, catheterization, and CMR were collated. Subjects were divided into three groups based on degree of rejection: acute rejection requiring new therapy, mild rejection requiring increased ongoing therapy, and no rejection with no change in treatment. Statistical analysis included student's t-test and linear regression. RESULTS: Peak and mean T1 values were significantly associated with acute rejection, with a monotonic trend observed with increased grade of rejection. Texture analysis demonstrated greater spatial heterogeneity in T1 values, as demonstrated by energy, entropy, and variance, in cases requiring treatment. Interestingly, 2 subjects who required increased therapy despite low grade EMB results had abnormal peak T1 values. Peak T1 values also correlated with increased BNP, right-sided filling pressures, and capillary wedge pressures. There was no difference in histopathological fibrosis percentage among the 3 groups; histopathological fibrosis did not correlate with T1 values or markers of graft dysfunction. CONCLUSION: In pediatric heart transplant patients, native T1 values identify acute rejection requiring treatment and may identify graft dysfunction. CMR shows promise as an important tool for evaluation of cardiac grafts in children, with T1 imaging outperforming biopsy findings in the assessment of rejection.
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Trasplante de Corazón , Niño , Fibrosis , Rechazo de Injerto/diagnóstico por imagen , Rechazo de Injerto/patología , Trasplante de Corazón/efectos adversos , Humanos , Imagen por Resonancia Magnética , Miocardio/patología , Péptido Natriurético Encefálico , Valor Predictivo de las Pruebas , Donantes de TejidosRESUMEN
BACKGROUND: After diagnosis of a cardiac mass, clinicians must weigh the benefits and risks of ascertaining a tissue diagnosis. Limited data are available on the accuracy of previously developed noninvasive pediatric cardiac magnetic resonance (CMR)-based diagnostic criteria. OBJECTIVES: The goals of this study were to: 1) evaluate the CMR characteristics of pediatric cardiac masses from a large international cohort; 2) test the accuracy of previously developed CMR-based diagnostic criteria; and 3) expand diagnostic criteria using new information. METHODS: CMR studies (children 0-18 years of age) with confirmatory histological and/or genetic diagnosis were analyzed by 2 reviewers, without knowledge of prior diagnosis. Diagnostic accuracy was graded as: 1) single correct diagnosis; 2) correct diagnosis among a differential; or 3) incorrect diagnosis. RESULTS: Of 213 cases, 174 (82%) had diagnoses that were represented in the previously published diagnostic criteria. In 70% of 174 cases, both reviewers achieved a single correct diagnosis (94% of fibromas, 71% of rhabdomyomas, and 50% of myxomas). When ≤2 differential diagnoses were included, both reviewers reached a correct diagnosis in 86% of cases. Of 29 malignant tumors, both reviewers indicated malignancy as a single diagnosis in 52% of cases. Including ≤2 differential diagnoses, both reviewers indicated malignancy in 83% of cases. Of 6 CMR sequences examined, acquisition of first-pass perfusion and late gadolinium enhancement were independently associated with a higher likelihood of a single correct diagnosis. CONCLUSIONS: CMR of cardiac masses in children leads to an accurate diagnosis in most cases. A comprehensive imaging protocol is associated with higher diagnostic accuracy.
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Medios de Contraste , Neoplasias Cardíacas , Niño , Gadolinio , Neoplasias Cardíacas/diagnóstico por imagen , Neoplasias Cardíacas/patología , Humanos , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Cinemagnética/métodos , Valor Predictivo de las Pruebas , Estudios RetrospectivosRESUMEN
BACKGROUND: A novel paediatric disease, multi-system inflammatory syndrome in children, has emerged during the 2019 coronavirus disease pandemic. OBJECTIVES: To describe the short-term evolution of cardiac complications and associated risk factors in patients with multi-system inflammatory syndrome in children. METHODS: Retrospective single-centre study of confirmed multi-system inflammatory syndrome in children treated from 29 March, 2020 to 1 September, 2020. Cardiac complications during the acute phase were defined as decreased systolic function, coronary artery abnormalities, pericardial effusion, or mitral and/or tricuspid valve regurgitation. Patients with or without cardiac complications were compared with chi-square, Fisher's exact, and Wilcoxon rank sum. RESULTS: Thirty-nine children with median (interquartile range) age 7.8 (3.6-12.7) years were included. Nineteen (49%) patients developed cardiac complications including systolic dysfunction (33%), valvular regurgitation (31%), coronary artery abnormalities (18%), and pericardial effusion (5%). At the time of the most recent follow-up, at a median (interquartile range) of 49 (26-61) days, cardiac complications resolved in 16/19 (84%) patients. Two patients had persistent mild systolic dysfunction and one patient had persistent coronary artery abnormality. Children with cardiac complications were more likely to have higher N-terminal B-type natriuretic peptide (p = 0.01), higher white blood cell count (p = 0.01), higher neutrophil count (p = 0.02), severe lymphopenia (p = 0.05), use of milrinone (p = 0.03), and intensive care requirement (p = 0.04). CONCLUSION: Patients with multi-system inflammatory syndrome in children had a high rate of cardiac complications in the acute phase, with associated inflammatory markers. Although cardiac complications resolved in 84% of patients, further long-term studies are needed to assess if the cardiac abnormalities (transient or persistent) are associated with major cardiac events.
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COVID-19 , Anomalías Cardiovasculares , Enfermedad de la Arteria Coronaria , Derrame Pericárdico , COVID-19/complicaciones , Niño , Preescolar , Humanos , Derrame Pericárdico/etiología , Estudios Retrospectivos , SARS-CoV-2 , Síndrome de Respuesta Inflamatoria SistémicaRESUMEN
BACKGROUND: The interventional cardiac magnetic resonance imaging suite combines a cardiac catheterization x-ray laboratory with a magnetic resonance imaging suite. At the study institution, interventional cardiac magnetic resonance imaging procedures (ie, magnetic resonance imaging-guided cardiac catheterizations) have been performed under institutional review board-approved research protocols since 2015. Because the workplace incorporates x-ray and magnetic resonance imaging in a highly technical environment, education about the importance of magnet safety is crucial to ensure the safety of patients and staff. OBJECTIVE: To promote magnetic resonance imaging safety and staff preparedness to respond in emergency situations in a specialized interventional cardiac magnetic resonance imaging environment. METHODS: Quarterly in situ evacuation drills with a live volunteer were implemented. A retrospective participant survey using a Likert scale was conducted. Evacuations were timed from the cardiac arrest code alert to safe evacuation or defibrillation if appropriate. RESULTS: Over 4 years, 14 drills were performed. Twenty-nine of 48 participants responded to the survey, a 60% response rate. Most participants agreed or strongly agreed that the drills were a positive experience (90%) and that the drills increased their confidence in their ability to perform in an evacuation scenario (100%). Room evacuation times improved from 71 to 41 seconds. No patient or staff safety events occurred in the interventional cardiac magnetic resonance imaging environment. CONCLUSION: Magnetic resonance imaging-guided cardiac catheterization evacuation drills promote preparedness, ensure patient and staff safety, and improve evacuation time in the interventional cardiac magnetic resonance imaging environment.
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Cateterismo Cardíaco , Imagen por Resonancia Magnética Intervencional , Corazón , Humanos , Imagen por Resonancia Magnética , Estudios RetrospectivosRESUMEN
Cu2ZnGeSe4 (CZGSe) is a promising earth-abundant and non-toxic semiconductor material for large-scale thin-film solar cell applications. Herein, we have employed a joint computational and experimental approach to characterize and assess the structural, optoelectronic, and heterojunction band offset and alignment properties of a CZGSe solar absorber. The CZGSe films were successfully prepared using DC-sputtering and e-beam evaporation systems and confirmed by XRD and Raman spectroscopy analyses. The CZGSe films exhibit a bandgap of 1.35 eV, as estimated from electrochemical cyclic voltammetry (CV) measurements and validated by first-principles density functional theory (DFT) calculations, which predicts a bandgap of 1.38 eV. A fabricated device based on the CZGSe as a light absorber and CdS as a buffer layer yields power conversion efficiency (PCE) of 4.4% with VOC of 0.69 V, FF of 37.15, and Jsc of 17.12 mA cm-2. Therefore, we suggest that interface and band offset engineering represent promising approaches to improve the performance of CZGSe devices by predicting a type-II staggered band alignment with a small conduction band offset of 0.18 eV at the CZGSe/CdS interface.
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Ternary Cu2SnS3 (CTS) is an attractive nontoxic and earth-abundant absorber material with suitable optoelectronic properties for cost-effective photoelectrochemical applications. Herein, we report the synthesis of high-quality CTS nanoparticles (NPs) using a low-cost facile hot injection route, which is a very simple and nontoxic synthesis method. The structural, morphological, optoelectronic, and photoelectrochemical (PEC) properties and heterojunction band alignment of the as-synthesized CTS NPs have been systematically characterized using various state-of-the-art experimental techniques and atomistic first-principles density functional theory (DFT) calculations. The phase-pure CTS NPs confirmed by X-ray diffraction (XRD) and Raman spectroscopy analyses have an optical band gap of 1.1 eV and exhibit a random distribution of uniform spherical particles with size of approximately 15-25 nm as determined from high-resolution transmission electron microscopy (HR-TEM) images. The CTS photocathode exhibits excellent photoelectrochemical properties with PCE of 0.55% (fill factor (FF) = 0.26 and open circuit voltage (Voc) = 0.54 V) and photocurrent density of -3.95 mA/cm2 under AM 1.5 illumination (100 mW/cm2). Additionally, the PEC activities of CdS and ZnS NPs are investigated as possible photoanodes to create a heterojunction with CTS to enhance the PEC activity. CdS is demonstrated to exhibit a higher current density than ZnS, indicating that it is a better photoanode material to form a heterojunction with CTS. Consistently, we predict a staggered type-II band alignment at the CTS/CdS interface with a small conduction band offset (CBO) of 0.08 eV compared to a straddling type-I band alignment at the CTS/ZnS interface with a CBO of 0.29 eV. The observed small CBO at the type-II band aligned CTS/CdS interface points to efficient charge carrier separation and transport across the interface, which are necessary to achieve enhanced PEC activity. The facile CTS synthesis, PEC measurements, and heterojunction band alignment results provide a promising approach for fabricating next-generation Cu-based light-absorbing materials for efficient photoelectrochemical applications.
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BACKGROUND: The benefits of cardiac magnetic resonance imaging (MRI) in the pediatric population must be balanced with the risk and cost of anesthesia. Segmented imaging using multiple averages attempts to avoid breath-holds requiring general anesthesia; however, cardiorespiratory artifacts and prolonged scan times limit its use. Thus, breath-held imaging with general anesthesia is used in many pediatric centers. The advent of free-breathing, motion-corrected (MOCO) cines by real-time re-binned reconstruction offers reduced anesthesia exposure without compromising image quality. OBJECTIVE: This study evaluates sedation utilization in our pediatric cardiac MR practice before and after clinical introduction of free-breathing MOCO imaging for cine and late gadolinium enhancement. MATERIALS AND METHODS: In a retrospective study, patients referred for a clinical cardiac MR who would typically be offered sedation for their scan (n=295) were identified and divided into two eras, those scanned before the introduction of MOCO cine and late gadolinium enhancement sequences and those scanned following their introduction. Anesthesia use was compared across eras and disease-specific cohorts. RESULTS: The incidence of non-sedation studies performed in children nearly tripled following the introduction of MOCO imaging (25% [pre-MOCO] to 69% [post-MOCO], P<0.01), with the greatest effect in patients with simple congenital heart disease. Eleven percent of the post-MOCO cohort comprised infants younger than 3 months of age who could forgo sedation with the combination of MOCO imaging and a "feed-and-bundle" positioning technique. CONCLUSION: Implementation of cardiac MR with MOCO cine and late gadolinium enhancement imaging in a pediatric population is associated with significantly decreased sedation utilization.
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Anestesia/estadística & datos numéricos , Medios de Contraste , Gadolinio , Cardiopatías/diagnóstico por imagen , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Niño , Estudios de Cohortes , Femenino , Corazón/diagnóstico por imagen , Humanos , Masculino , Respiración , Estudios Retrospectivos , TiempoRESUMEN
BACKGROUND: Monitoring for acute allograft rejection improves outcomes after cardiac transplantation. Endomyocardial biopsy is the gold standard test defining rejection, but carries risk and has limitations. Cardiac magnetic resonance T2 mapping may be able to predict rejection in adults, but has not been studied in children. Our aim was to evaluate T2 mapping in identifying paediatric cardiac transplant patients with acute rejection. METHODS: Eleven paediatric transplant patients presenting 18 times were prospectively enrolled for non-contrast cardiac magnetic resonance at 1.5 T followed by endomyocardial biopsy. Imaging included volumetry, flow, and T2 mapping. Regions of interest were manually selected on the T2 maps using the middle-third technique in the left ventricular septal and lateral wall in a short-axis and four-chamber slice. Mean and maximum T2 values were compared with Student's t-tests analysis. RESULTS: Five cases of acute rejection were identified in three patients, including two cases of grade 2R on biopsy and three cases of negative biopsy treated for clinical symptoms attributed to rejection (new arrhythmia, decreased exercise capacity). A monotonic trend between increasing T2 values and higher biopsy grades was observed: grade 0R T2 53.4 ± 3 ms, grade 1R T2 54.5 ms ± 3 ms, grade 2R T2 61.3 ± 1 ms. The five rejection cases had significantly higher mean T2 values compared to cases without rejection (58.3 ± 4 ms versus 53 ± 2 ms, p = 0.001). CONCLUSIONS: Cardiac magnetic resonance with quantitative T2 mapping may offer a non-invasive method for screening paediatric cardiac transplant patients for acute allograft rejection. More data are needed to understand the relationship between T2 and rejection in children.
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Rechazo de Injerto/diagnóstico por imagen , Trasplante de Corazón/efectos adversos , Imagen por Resonancia Cinemagnética , Miocardio/patología , Enfermedad Aguda , Adolescente , Niño , Preescolar , Femenino , Rechazo de Injerto/patología , Humanos , Modelos Logísticos , Masculino , Valor Predictivo de las Pruebas , Trasplante Homólogo , Resultado del Tratamiento , Estados UnidosRESUMEN
INTRODUCTION: Pediatric z scores are necessary to describe size and structure of the heart in growing children, however, development of an accurate z score calculator requires robust normal datasets, which are difficult to obtain with cardiovascular magnetic resonance (CMR) in children. Motion-corrected (MOCO) cines from re-binned, reconstructed real-time cine offer a free-breathing, rapid acquisition resulting in cines with high spatial and temporal resolution. In combination with child-friendly positioning and entertainment, MOCO cine technique allows for rapid cine volumetry in patients of all ages without sedation. Thus, our aim was to prospectively enroll normal infants and children birth-12 years for creation and validation of a z score calculator describing normal right ventricular (RV) and left ventricular (LV) size. METHODS: With IRB approval and consent/assent, 149 normal children successfully underwent a brief noncontrast CMR on a 1.5 T scanner including MOCO cines in the short axis, and RV and LV volumes were measured. 20% of scans were re-measured for interobserver variability analyses. A general linear modeling (GLM) framework was employed to identify and properly represent the relationship between CMR-based assessments and anthropometric data. Scatter plots of model fit and Akaike's information criteria (AIC) results were used to guide the choice among alternative models. RESULTS: A total of 149 subjects aged 22 days-12 years (average 5.1 ± 3.6 years), with body surface area (BSA) range 0.21-1.63 m2 (average 0.8 ± 0.35 m2) were scanned. All ICC values were > 95%, reflecting excellent agreement between raters. The model that provided the best fit of volume measure to the data included BSA with higher order effects and gender as independent variables. Compared with earlier z score models, there is important additional growth inflection in early toddlerhood with similar z score prediction in later childhood. CONCLUSIONS: Free-breathing, MOCO cines allow for accurate, reliable RV and LV volumetry in a wide range of infants and children while awake. Equations predicting fit between LV and RV normal values and BSA are reported herein for purposes of creating z scores. TRIAL REGISTRATION: clinicaltrials.gov NCT02892136, Registered 7/21/2016.
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Desarrollo Infantil , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/crecimiento & desarrollo , Imagen por Resonancia Cinemagnética , Función Ventricular Izquierda , Función Ventricular Derecha , Factores de Edad , Niño , Preescolar , Femenino , Voluntarios Sanos , Humanos , Lactante , Recién Nacido , Masculino , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Estudios Prospectivos , Valores de Referencia , Reproducibilidad de los Resultados , VigiliaRESUMEN
Four-dimensional flow cardiac magnetic resonance enhances the visualization of blood flow in a 3-dimensional volume throughout the cardiac cycle, thus dramatically improving visualization of pulmonary venous anatomy by cardiac magnetic resonance. We demonstrate the impact of 4-dimensional flow on diagnosis and surgical planning for partial anomalous pulmonary venous return. (Level of Difficulty: Beginner.).
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PURPOSE: In transposition of great arteries, increased right ventricular (RV) afterload is observed following arterial switch operation (ASO), which is not always related to pulmonary artery (PA) stenosis. We hypothesize that abnormal PA bending from the Lecompte maneuver may affect RV afterload in the absence of stenosis. Thus, we sought to identify novel measurements of three-dimensional cardiac magnetic resonance (CMR) images of the pulmonary arteries and compare with conventional measurements in their ability to predict RV afterload. METHODS: Conventional measurements and novel measurements of the pulmonary arteries were performed using CMR data from 42 ASO patients and 13 age-matched controls. Novel measurements included bending angle, normalized radius of curvature (Rc), and normalized weighted radius of curvature (Rc-w). Right ventricular systolic pressures (as the surrogate for RV afterload) were measured by either recent echocardiogram or cardiac catheterization. RESULTS: Conventional measurements of proximal PA size correlated with differential pulmonary blood flow (r = 0.49, P = .001), but not with RV peak systolic pressures (r = -0.26, P = .18). In ASO patients, Rc-w correlated with higher RV systolic pressures (r = -0.57, P = .002). Larger neoaortic areas and rightward bending angles correlated with smaller right pulmonary artery Rc (r = -0.48, P = .001; r = 0.41, P = .01, respectively). Finally, both pulmonary arteries had significantly smaller Rc compared to normal controls. CONCLUSIONS: Pulmonary arteries exhibit abnormal bends following ASO that correlate with increased RV afterload, independent of PA stenosis. Future work should focus on clinical and hemodynamic contributions of these shape parameters.
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Operación de Switch Arterial/métodos , Ventrículos Cardíacos/fisiopatología , Ventrículos Cardíacos/cirugía , Arteria Pulmonar/anomalías , Arteria Pulmonar/cirugía , Adolescente , Operación de Switch Arterial/efectos adversos , Cateterismo Cardíaco , Niño , Preescolar , Constricción Patológica , Ecocardiografía , Femenino , Hemodinámica , Humanos , Pulmón , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Sístole , Función Ventricular DerechaRESUMEN
Despite numerous advances in medical and surgical management, congenital heart disease (CHD) remains the number one cause of death in the first year of life from congenital malformations. The current strategies used to approach improving outcomes in CHD are varied. This article will discuss the recent impact of pulse oximetry screening for critical CHD, describe the contributions of advanced cardiac imaging in the neonate with CHD, and highlight the growing importance of quality improvement and safety programs in the cardiac intensive care unit.
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Cardiopatías Congénitas/diagnóstico , Corazón/diagnóstico por imagen , Tamizaje Neonatal/métodos , Unidades de Cuidados Coronarios/normas , Ecocardiografía , Cardiopatías Congénitas/diagnóstico por imagen , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal/normas , Imagen por Resonancia Magnética , Tamizaje Neonatal/normas , Oximetría , Mejoramiento de la Calidad , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
OBJECTIVES: To determine whether X-ray fused with MRI (XFM) is beneficial for select transcatheter congenital heart disease interventions. BACKGROUND: Complex transcatheter interventions often require three-dimensional (3D) soft tissue imaging guidance. Fusion imaging with live X-ray fluoroscopy can potentially improve and simplify procedures. METHODS: Patients referred for select congenital heart disease interventions were prospectively enrolled. Cardiac MRI data was overlaid on live fluoroscopy for procedural guidance. Likert scale operator assessments of value were recorded. Fluoroscopy time, radiation exposure, contrast dose, and procedure time were compared to matched cases from our institutional experience. RESULTS: Forty-six patients were enrolled. Pre-catheterization, same day cardiac MRI findings indicated intervention should be deferred in nine patients. XFM-guided cardiac catheterization was performed in 37 (median age 8.7 years [0.5-63 years]; median weight 28 kg [5.6-110 kg]) with the following prespecified indications: pulmonary artery (PA) stenosis (n = 13), aortic coarctation (n = 12), conduit stenosis/insufficiency (n = 9), and ventricular septal defect (n = 3). Diagnostic catheterization showed intervention was not indicated in 12 additional cases. XFM-guided intervention was performed in the remaining 25. Fluoroscopy time was shorter for XFM-guided intervention cases compared to matched controls. There was no significant difference in radiation dose area product, contrast volume, or procedure time. Operator Likert scores indicated XFM provided useful soft tissue guidance in all cases and was never misleading. CONCLUSIONS: XFM provides operators with meaningful three-dimensional soft tissue data and reduces fluoroscopy time in select congenital heart disease interventions.
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Cateterismo Cardíaco , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/terapia , Imagen por Resonancia Magnética , Radiografía Intervencional , Adolescente , Adulto , Cateterismo Cardíaco/efectos adversos , Niño , Preescolar , Toma de Decisiones Clínicas , Medios de Contraste/administración & dosificación , Femenino , Fluoroscopía , Humanos , Lactante , Imagen por Resonancia Magnética/efectos adversos , Masculino , Persona de Mediana Edad , Imagen Multimodal , Selección de Paciente , Valor Predictivo de las Pruebas , Estudios Prospectivos , Dosis de Radiación , Exposición a la Radiación , Radiografía Intervencional/efectos adversos , Factores de Riesgo , Resultado del Tratamiento , Adulto JovenRESUMEN
Cardiac catheterization is an integral part of medical management for pediatric patients with congenital heart disease. Owing to age and lack of cooperation in children who need this procedure, general anesthesia is typically required. These patients have increased anesthesia risk secondary to cardiac pathology. Furthermore, multiple catheterization procedures result in exposure to harmful ionizing radiation. Magnetic resonance imaging-guided right-heart catheterization offers decreased radiation exposure and diagnostic imaging benefits over traditional fluoroscopy but potentially increases anesthetic complexity and risk. We describe our early experience with anesthetic techniques and challenges for pediatric magnetic resonance imaging-guided right-heart catheterization.