RESUMO
Background: Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is an inherited, progressive form of cardiomyopathy, which is characterized by fibrofatty replacement of the myocardium. While the gold standard for diagnosis remains pathologic evaluation of biopsy, advances in noninvasive imaging, including cardiac magnetic resonance imaging (CMRI), have led to improved clinical diagnosis.Case report: We report three additional cases of pediatric patients that have pathologically confirmed ARVC/D with CMRI images, demonstrating extensive macroscopic fatty infiltration of the right and left ventricular myocardium. The identification using CMRI allowed timely transplantation and patient survival.Conclusion: Our study is designed to highlight how fibrofatty changes are minimal using CMRI in the pediatric population and how this can be a valuable tool to provide an additional method of diagnosis.
Assuntos
Displasia Arritmogênica Ventricular Direita , Displasia Arritmogênica Ventricular Direita/diagnóstico por imagem , Biópsia , Criança , Ventrículos do Coração/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , MiocárdioRESUMO
For many neuromuscular diseases (NMDs), cardiac disease represents a major cause of morbidity and mortality. The management of cardiac disease in NMDs is made challenging by the broad clinical heterogeneity that exists among many NMDs and by limited knowledge about disease-specific cardiovascular pathogenesis and course-modifying interventions. The overlay of compromise in peripheral muscle function and other organ systems, such as the lungs, also makes the simple application of endorsed adult or pediatric heart failure guidelines to the NMD population problematic. In this statement, we provide background on several NMDs in which there is cardiac involvement, highlighting unique features of NMD-associated myocardial disease that require clinicians to tailor their approach to prevention and treatment of heart failure. Undoubtedly, further investigations are required to best inform future guidelines on NMD-specific cardiovascular health risks, treatments, and outcomes.
Assuntos
Cardiomiopatias/diagnóstico , Doenças Musculares/diagnóstico , Doenças Neuromusculares/diagnóstico , American Heart Association , Síndrome de Barth/diagnóstico , Síndrome de Barth/genética , Síndrome de Barth/metabolismo , Síndrome de Barth/patologia , Cardiomiopatias/complicações , Cardiomiopatias/patologia , Ataxia de Friedreich/diagnóstico , Ataxia de Friedreich/metabolismo , Ataxia de Friedreich/patologia , Humanos , Doenças Musculares/metabolismo , Doenças Musculares/patologia , Distrofia Muscular do Cíngulo dos Membros/diagnóstico , Distrofia Muscular do Cíngulo dos Membros/metabolismo , Distrofia Muscular do Cíngulo dos Membros/patologia , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/patologia , Distrofia Muscular de Emery-Dreifuss/diagnóstico , Distrofia Muscular de Emery-Dreifuss/metabolismo , Distrofia Muscular de Emery-Dreifuss/patologia , Miopatias Congênitas Estruturais/diagnóstico , Miopatias Congênitas Estruturais/genética , Miopatias Congênitas Estruturais/metabolismo , Miopatias Congênitas Estruturais/patologia , Distrofia Miotônica/diagnóstico , Distrofia Miotônica/metabolismo , Distrofia Miotônica/patologia , Doenças Neuromusculares/complicações , Doenças Neuromusculares/patologia , Fatores de Risco , Estados UnidosRESUMO
BACKGROUND: Improved delineation of vascular structures is a common indication for cardiovascular magnetic resonance (CMR) in children and requires high spatial resolution. Currently, pre-contrast 3D, respiratory navigated, T2-prepared, fat saturated imaging with a bSSFP readout (3D bSSFP) is commonly used; however, these images can be limited by blood pool inhomogeneity and exaggeration of metal artifact. We compared image quality of pediatric vasculature obtained using standard 3D bSSFP to 3D, respiratory navigated, inversion recovery prepared imaging with a gradient echo readout (3D IR GRE) performed after administration of gadofosveset trisodium (GT), a blood pool contrast agent. METHODS: For both sequences, VCG triggering was used with acquisition during a quiescent period of the cardiac cycle. 3D bSSFP imaging was performed pre-contrast, and 3D IR GRE imaging was performed 5 min after GT administration. We devised a vascular imaging quality score (VIQS) with subscores for coronary arteries, pulmonary arteries and veins, blood pool homogeneity, and metal artifact. Scoring was performed on axial reconstructions of isotropic datasets by two independent readers and differences were adjudicated. Signal- and contrast-to-noise (SNR and CNR) calculations were performed on each dataset. RESULTS: Thirty-five patients had both 3D bSSFP and 3D IR GRE imaging performed. 3D IR GRE imaging showed improved overall vascular imaging compared to 3D bSSFP when comparing all-patient VIQS scores (n = 35, median 14 (IQR 11-15), vs 6 (4-10), p < 0.0001), and when analyzing the subset of patients with intrathoracic metal (n = 17, 16 (14-17) vs. 5 (2-9), p < 0.0001). 3D IR GRE showed significantly improved VIQS subscores for imaging the RCA, pulmonary arteries, pulmonary veins, and blood pool homogeneity. In addition, 3D IR GRE imaging showed reduced variability in both all-patient and metal VIQS scores compared to 3D bSSFP (p < 0.05). SNR and CNR were higher with 3D IR GRE in the left ventricle and left atrium, but not the pulmonary arteries. CONCLUSIONS: Respiratory navigated 3D IR GRE imaging after GT administration provides improved vascular CMR in pediatric patients compared to pre-contrast 3D bSSFP imaging, as well as improved imaging in patients with intrathoracic metal. It is an excellent alternative in this challenging patient population when high spatial resolution vascular imaging is needed.
Assuntos
Meios de Contraste/administração & dosagem , Angiografia Coronária/métodos , Vasos Coronários/diagnóstico por imagem , Gadolínio/administração & dosagem , Cardiopatias Congênitas/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Angiografia por Ressonância Magnética/métodos , Compostos Organometálicos/administração & dosagem , Artéria Pulmonar/diagnóstico por imagem , Veias Pulmonares/diagnóstico por imagem , Mecânica Respiratória , Adolescente , Fatores Etários , Artefatos , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto JovemRESUMO
BACKGROUND: Cardiac MRI has become widespread to characterize cardiac lesions in children. No study has examined the role of deep sedation performed by non-anesthesiologists for this investigation. OBJECTIVE: We hypothesized that deep sedation provided by non-anesthesiologists can be provided with a similar safety and efficacy profile to general anesthesia provided by anesthesiologists. MATERIALS AND METHODS: This is a retrospective chart review of children who underwent cardiac MRI over a 5-year period. The following data were collected from the medical records: demographic data, cardiac lesion, American Society of Anesthesiologists (ASA) physical status, sedation type, provider, medications, sedation duration and adverse events or interventions. Image and sedation adequacy were recorded. RESULTS: Of 1,465 studies identified, 1,197 met inclusion criteria; 43 studies (3.6%) used general anesthesia, 506 (42.3%) had deep sedation and eight (0.7%) required anxiolysis only. The remaining 640 studies (53.5%) were performed without sedation. There were two complications in the general anesthesia group (4.7%) versus 17 in the deep sedation group (3.4%). Sedation was considered inadequate in 22 of the 506 deep sedation patients (4.3%). Adequate images were obtained in 95.3% of general anesthesia patients versus 86.6% of deep sedation patients. CONCLUSION: There was no difference in the incidence of adverse events or cardiac MRI image adequacy for children receiving general anesthesia by anesthesiologists versus deep sedation by non-anesthesiologists. In summary, this study demonstrates that an appropriately trained sedation provider can provide deep sedation for cardiac MRI without the need for general anesthesia in selected cases.
Assuntos
Sedação Profunda/estatística & dados numéricos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Cardiopatias/diagnóstico , Cardiopatias/epidemiologia , Hipnóticos e Sedativos/uso terapêutico , Imagem Cinética por Ressonância Magnética/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Comorbidade , Feminino , Georgia/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Prevalência , Estudos Retrospectivos , Medição de Risco , Estresse Psicológico/epidemiologia , Estresse Psicológico/prevenção & controleRESUMO
This article introduces a novel method named "Parallel Imaging and Noquist in Tandem" (PINOT) for accelerated image acquisition of cine cardiac magnetic resonance imaging. This method combines two prior information formalisms, the SPACE-RIP implementation of parallel imaging and the Noquist method for reduced-data image reconstruction with prior knowledge of static and dynamic regions in the field of view. The general theory is presented, and supported by results from experiments using time-resolved two-dimensional simulation data and retrospectively sub-sampled magnetic resonance imaging data with acceleration factors around 4. A signal-to-noise ratio analysis and a comparison study with TSENSE and k-t SENSE show that PINOT performs favorably in preserving edge detail, at a cost in signal-to-noise ratio and computational complexity.
Assuntos
Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imagem Cinética por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Congenital bicuspid aortic valve (BAV) is a significant risk factor for serious complications including valve dysfunction, aortic dilatation, dissection, and sudden death. Clinical tools for identification and monitoring of BAV patients at high risk for development of aortic dilatation, an early complication, are not available. METHODS: This paper reports an investigation in 18 pediatric BAV patients and 10 normal controls of links between abnormal blood flow patterns in the ascending aorta and aortic dilatation using velocity-encoded cardiovascular magnetic resonance. Blood flow patterns were quantitatively expressed in the angle between systolic left ventricular outflow and the aortic root channel axis, and also correlated with known biochemical markers of vessel wall disease. RESULTS: The data confirm larger ascending aortas in BAV patients than in controls, and show more angled LV outflow in BAV (17.54 +/- 0.87 degrees) than controls (10.01 +/- 1.29) (p = 0.01). Significant correlation of systolic LV outflow jet angles with dilatation was found at different levels of the aorta in BAV patients STJ: r = 0.386 (N = 18, p = 0.048), AAO: r = 0.536 (N = 18, p = 0.022), and stronger correlation was found with patients and controls combined into one population: SOV: r = 0.405 (N = 28, p = 0.033), STJ: r = 0.562 (N = 28, p = 0.002), and AAO r = 0.645 (N = 28, p < 0.001). Dilatation and the flow jet angle were also found to correlate with plasma levels of matrix metallo-proteinase 2. CONCLUSIONS: The results of this study provide new insights into the pathophysiological processes underlying aortic dilatation in BAV patients. These results show a possible path towards the development of clinical risk stratification protocols in order to reduce morbidity and mortality for this common congenital heart defect.
Assuntos
Aorta/patologia , Doenças da Aorta/diagnóstico , Valva Aórtica/anormalidades , Cardiopatias Congênitas/complicações , Hemodinâmica , Imagem Cinética por Ressonância Magnética , Adolescente , Aorta/fisiopatologia , Doenças da Aorta/etiologia , Doenças da Aorta/fisiopatologia , Valva Aórtica/fisiopatologia , Biomarcadores/sangue , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Criança , Dilatação Patológica , Ecocardiografia Doppler , Feminino , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/fisiopatologia , Humanos , Masculino , Metaloproteinase 2 da Matriz/sangue , Metaloproteinase 9 da Matriz/sangue , Valor Preditivo dos Testes , Estudos Prospectivos , Fluxo Sanguíneo Regional , Inibidores Teciduais de Metaloproteinases/sangueRESUMO
Vascular ring in the form of a double aortic arch is a rare anomaly that can cause airway compression. It occasionally occurs with unusual head and neck vessel branching. A 5-year-old boy with chronic respiratory symptoms was referred because of a tracheal indentation on his chest x-ray. Magnetic resonance imaging showed a double aortic arch with arch origins of a common carotid, vertebral, and subclavian on the right and internal and external carotids, vertebral, and subclavian arteries on the left. Our case represents, to our knowledge, the first report of a double aortic arch with 7 separate vessels arising from the transverse arches.
Assuntos
Aorta Torácica/anormalidades , Artéria Subclávia/anormalidades , Malformações Vasculares/diagnóstico , Aorta Torácica/diagnóstico por imagem , Pré-Escolar , Diagnóstico Diferencial , Humanos , Angiografia por Ressonância Magnética , Masculino , Artéria Subclávia/diagnóstico por imagemRESUMO
BACKGROUND: In our multicenter study of the total cavopulmonary connection (TCPC), a cohort of patients with long-segment left pulmonary artery (LPA) stenosis was observed (35%). The clinically recognized detrimental effects of LPA stenosis motivated a computational fluid dynamic simulation study within 3-dimensional patient-specific and idealized TCPC pathways. The goal of this study was to quantify and evaluate the hemodynamic impact of LPA stenosis and to judge interventional strategies aimed at treating it. METHODS AND RESULTS: Simulations were conducted at equal vascular lung resistance, modeling both discrete stenosis (DS) and diffuse long-segment hypoplasia with varying degrees of obstruction (0% to 80%). Models having fenestrations of 2 to 6 mm and atrium pressures of 4 to 14 mm Hg were explored. A patient-specific, extracardiac TCPC with 85% DS was studied in its original configuration and after virtual surgery that dilated the LPA to 0% stenosis in the computer medium. Performance indices improved exponentially (R2>0.99) with decreasing obstruction. Diffuse long-segment hypoplasia was approximately 50% more severe with regard to lung perfusion and cardiac energy loss than DS. Virtual angioplasty performed on the 3-dimensional Fontan anatomy exhibiting an 85% DS stenosis produced a 61% increase in left lung perfusion and a 50% decrease in cardiac energy dissipation. After 4-mm fenestration, TCPC baffle pressure dropped by approximately 10% and left lung perfusion decreased by approximately 8% compared with the 80% DS case. CONCLUSIONS: DS <60% and diffuse long-segment hypoplasia <40% could be considered tolerable because both resulted in only a 12% decrease in left lung perfusion. In contrast to angioplasty, a fenestration (right-to-left shunt) reduced TCPC pressure at the cost of decreased left and right lung perfusion. These results suggest that pre-Fontan computational fluid dynamic simulation may be valuable for determining both the hemodynamic significance of LPA stenosis and the potential benefits of intervention.
Assuntos
Técnica de Fontan , Derivação Cardíaca Direita , Modelos Cardiovasculares , Artéria Pulmonar/patologia , Artéria Pulmonar/cirurgia , Angioplastia , Simulação por Computador , Constrição Patológica , Bases de Dados Factuais , Humanos , Imageamento Tridimensional , Técnicas In Vitro , Pulmão/irrigação sanguínea , Pulmão/fisiologia , Artéria Pulmonar/fisiologia , Circulação Pulmonar , Interface Usuário-Computador , Resistência VascularRESUMO
In pediatric ventricular assist device (VAD) design, the process of matching device characteristics and dimensions to the relevant disease conditions poses a formidable challenge because the disease spectrum is more highly varied than for adult applications. One example arises with single-ventricle congenital defects, which demand palliative surgeries that create elevated systemic venous pressure and altered pulmonary hemodynamics. Substituting a mechanical pump as a right ventricle has long been proposed to eliminate the associated early and postoperative anomalies. A pulsatile lumped-parameter model of the single-ventricle circulation was developed to guide the preliminary design studies. Two special modules, the pump characteristics and the total cavopulmonary connection (TCPC) module, are introduced. The TCPC module incorporates the results of three-dimensional patient-specific computational fluid dynamics calculations, where the pressure drop in the TCPC anastomosis is calculated at the equal vascular lung resistance operating point for different cardiac outputs at a steady 60/40 inferior vena cava/superior vena cava flow split. Preliminary results obtained with the adult parameters are presented with no ventricle remodeling or combined larger-size single ventricle. A detailed literature review of single-ventricle function is provided. Coupling a continuous pump to the single-ventricle circulation brought both the pulmonary and systemic venous pressures back to manageable levels. Selected VADs provided an acceptable cardiac output trace of the single left ventricle, after initial transients. Remodeling of the systemic venous compliance plays a critical role in performance and is included in this study. Pulsatile operation mode with rotational speed regulation highlighted the importance of TCPC and pulmonary artery compliances. Four different pumps and three patient-specific anatomical TCPC pathologies were studied. Magnitudes of the equivalent TCPC resistances were found to be comparable to the vascular resistances of the normal baseline circulation, significantly affecting both the VAD design and hemodynamics.
Assuntos
Simulação por Computador , Técnica de Fontan , Derivação Cardíaca Direita/instrumentação , Coração Auxiliar , Anastomose Cirúrgica , Criança , Complacência (Medida de Distensibilidade) , Cardiopatias Congênitas/cirurgia , Ventrículos do Coração/anormalidades , Hemodinâmica , Humanos , Modelos Cardiovasculares , Artéria Pulmonar/cirurgia , Fluxo Pulsátil , Literatura de Revisão como Assunto , Rotação , Veia Cava Inferior/cirurgia , Veia Cava Superior/cirurgiaRESUMO
In a cohort of 56 school-aged children with repaired tetralogy of Fallot, significant (moderate to severe) tricuspid regurgitation was common (32% of patients) and was related to both tricuspid annulus dilatation and structural valve abnormalities that were potentially related to previous surgery. Even after adjusting for pulmonary regurgitation, tricuspid regurgitation was significantly correlated with right ventricular volume (r= 0.39, p = 0.009), suggesting that tricuspid regurgitation as well as pulmonary regurgitation may contribute significantly to progressive right ventricular dilatation in this population.
Assuntos
Hipertrofia Ventricular Direita/etiologia , Complicações Pós-Operatórias/etiologia , Insuficiência da Valva Pulmonar/etiologia , Tetralogia de Fallot/complicações , Tetralogia de Fallot/cirurgia , Insuficiência da Valva Tricúspide/etiologia , Volume Cardíaco , Criança , Pré-Escolar , Progressão da Doença , Ecocardiografia Doppler em Cores , Seguimentos , Humanos , Hipertrofia Ventricular Direita/diagnóstico , Hipertrofia Ventricular Direita/fisiopatologia , Lactente , Imageamento por Ressonância Magnética , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/fisiopatologia , Prevalência , Insuficiência da Valva Pulmonar/diagnóstico , Insuficiência da Valva Pulmonar/fisiopatologia , Fatores de Risco , Índice de Gravidade de Doença , Volume Sistólico , Sístole , Fatores de Tempo , Insuficiência da Valva Tricúspide/classificação , Insuficiência da Valva Tricúspide/diagnóstico , Insuficiência da Valva Tricúspide/epidemiologia , Insuficiência da Valva Tricúspide/fisiopatologiaRESUMO
BACKGROUND: Surgical repair of obstructive lesions of the right ventricular outflow tract (RVOT) in children commonly creates pulmonary valve incompetence that may eventually require pulmonary valve replacement (PVR). We reviewed our experience with PVR late after RVOT reconstruction. METHODS: We performed 100 PVRs in 93 children 1.1 months to 22.4 years (median 8) after RVOT reconstruction. Children with right ventricular to pulmonary artery conduits and primary PVRs were excluded. Age at PVR was 4.5 months to 27.9 years (median 9.5 years). Initial diagnosis was tetralogy of Fallot and variants, 62; critical pulmonary stenosis, 15; pulmonary atresia with intact ventricular septum, 7; and others, 9. Eleven patients had a redo PVR. A total of 62 PVRs were homografts; 38 were porcine valves. RESULTS: There was one early death. On follow-up of 5 months to 12.4 years (mean 4.9 years) there were no late deaths although 1 child underwent cardiac transplantation. Actuarial freedom from redo PVR at 8 years was 100% for porcine valves but 70% for homograft valves (p = 0.17). For children younger than 3 years at PVR, freedom from reoperation was 76% at 1 year and 39% at 8 years compared with freedom from redo PVR at 8 years of 100% for children older than 3 years. On latest echocardiogram 97% of porcine valves had mild or no pulmonary regurgitation compared with 72% of homograft valves. CONCLUSIONS: PVR after RVOT reconstruction can be performed with low risk. Porcine valves may be superior to homograft valves although this advantage may be due to older age at time of PVR.
Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Complicações Pós-Operatórias/cirurgia , Insuficiência da Valva Pulmonar/cirurgia , Valva Pulmonar , Obstrução do Fluxo Ventricular Externo/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Complicações Pós-Operatórias/etiologia , Insuficiência da Valva Pulmonar/etiologia , ReoperaçãoRESUMO
BACKGROUND: Using a bifurcated Y-graft as the Fontan baffle is hypothesized to streamline and improve flow dynamics through the total cavopulmonary connection (TCPC). This study conducted numerical simulations to evaluate this hypothesis using postoperative data from 5 patients. METHODS: Patients were imaged with cardiac magnetic resonance or computed tomography after receiving a bifurcated aorto-iliac Y-graft as their Fontan conduit. Numerical simulations were performed using in vivo flow rates, as well as 2 levels of simulated exercise. Two TCPC models were virtually created for each patient to serve as the basis for hemodynamic comparison. Comparative metrics included connection flow resistance and inferior vena caval flow distribution. RESULTS: Results demonstrate good hemodynamic outcomes for the Y-graft options. The consistency of inferior vena caval flow distribution was improved over TCPC controls, whereas the connection resistances were generally no different from the TCPC values, except for 1 case in which there was a marked improvement under both resting and exercise conditions. Examination of the connection hemodynamics as they relate to surgical Y-graft implementation identified critical strategies and modifications that are needed to potentially realize the theoretical efficiency of such bifurcated connection designs. CONCLUSIONS: Five consecutive patients received a Y-graft connection to complete their Fontan procedure with positive hemodynamic results. Refining the surgical technique for implementation should result in further energetic improvements that may help improve long-term outcomes.
Assuntos
Prótese Vascular , Técnica de Fontan/métodos , Cardiopatias Congênitas/cirurgia , Hemodinâmica/fisiologia , Criança , Pré-Escolar , Simulação por Computador , Feminino , Técnica de Fontan/instrumentação , Humanos , Hidrodinâmica , Imageamento por Ressonância Magnética , Masculino , Modelos Cardiovasculares , Politetrafluoretileno , Desenho de Prótese , Fluxo Sanguíneo Regional , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
OBJECTIVE: Optimizing flow and diminishing power loss in the Fontan circuit can improve hemodynamic efficiency, potentially improving the long-term outcomes. Computerized modeling has predicted improved energetics with a Y-graft Fontan. METHODS: From August to December 2010, 6 consecutive children underwent completion Fontan (n=3) or Fontan revision (n=3) using a bifurcated polytetrafluoroethylene Y-graft (18×9×9 mm in 2, 20×10×10 mm in 4) connecting the inferior vena cava to the right and left pulmonary arteries with separate graft limbs. The patents underwent magnetic resonance imaging (n=5) or computed tomography (n=1). Computational fluid dynamics assessed Fontan hemodynamics, power loss, and inferior vena cava flow splits to the branch pulmonary arteries. The clinical parameters were compared with those from 12 patients immediately preceding the present series who had undergone a lateral Fontan procedure. RESULTS: Despite longer crossclamp and bypass times (not statistically significant), the Y-graft Fontan patients had postoperative courses similar to those of the conventional Fontan patients. Other than 2 early readmissions for pleural effusions managed with diuretics, at 6 to 12 months of follow-up (mean, 8 months), all 6 patients had done well. Postoperative flow modeling demonstrated a balanced distribution of inferior vena cava flow to both pulmonary arteries with minimal flow disturbance. Improvements in hemodynamics and efficiency were noted when the Y-graft branches were anastomosed distally and aligned tangentially with the branch pulmonary arteries. CONCLUSIONS: The present preliminary surgical experience has demonstrated the clinical feasibility of the bifurcated Y-graft Fontan. Computational fluid dynamics showed acceptable hemodynamics with low calculated power losses and a balanced distribution of inferior vena cava flow to the pulmonary arteries as long as the branch grafts were anastomosed distally.
Assuntos
Prótese Vascular , Técnica de Fontan/métodos , Cardiopatias Congênitas/cirurgia , Adolescente , Implante de Prótese Vascular , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Hemodinâmica , Humanos , Hidrodinâmica , Processamento de Imagem Assistida por Computador , Tempo de Internação , Imageamento por Ressonância Magnética , Masculino , Modelos Cardiovasculares , Reoperação , Respiração Artificial , Resultado do TratamentoRESUMO
OBJECTIVES: The aim of this study was to report the results of an international multicenter experience of cardiac magnetic resonance imaging (MRI) evaluation of cardiac tumors in children, each with histology correlation or a diagnosis of tuberous sclerosis, and to determine which characteristics are predictive of tumor type. BACKGROUND: Individual centers have relatively little experience with diagnostic imaging of cardiac tumors in children, because of their low prevalence. The accuracy of cardiac MRI diagnosis on the basis of a pre-defined set of criteria has not been tested. METHODS: An international group of pediatric cardiac imaging centers was solicited for case contribution. Inclusion criteria comprised: 1) age at diagnosis ≤18 years; 2) cardiac MRI evaluation of cardiac tumor; and 3) histologic diagnosis or diagnosis of tuberous sclerosis. Data from the cardiac MRI images were analyzed for mass characteristics. On the basis of pre-defined cardiac MRI criteria derived from published data, 3 blinded investigators determined tumor type, and their consensus diagnoses were compared with histologic diagnoses. RESULTS: Cases (n = 78) submitted from 15 centers in 4 countries had the following diagnoses: fibroma (n = 30), rhabdomyoma (n = 14), malignant tumor (n = 12), hemangioma (n = 9), thrombus (n = 4), myxoma (n = 3), teratoma (n = 2), and paraganglioma, pericardial cyst, Purkinje cell tumor, and papillary fibroelastoma (n = 1, each). Reviewers who were blinded to the histologic diagnoses correctly diagnosed 97% of the cases but included a differential diagnosis in 42%. Better image quality grade and more complete examination were associated with higher diagnostic accuracy. CONCLUSIONS: Cardiac MRI can predict the likely tumor type in the majority of children with a cardiac mass. A comprehensive imaging protocol is essential for accurate diagnosis. However, histologic diagnosis remains the gold standard, and in some cases malignancy cannot be definitively excluded on the basis of cardiac MRI images alone.
Assuntos
Neoplasias Cardíacas/patologia , Imageamento por Ressonância Magnética , Miocárdio/patologia , Adolescente , Criança , Pré-Escolar , Erros de Diagnóstico , Feminino , Fibroma/patologia , Hemangioma/patologia , Humanos , Lactente , Masculino , Estudos Retrospectivos , Rabdomioma/patologia , Teratoma/patologiaRESUMO
BACKGROUND: After tetralogy of Fallot (TOF) repair, severe pulmonary insufficiency is known to impair biventricular function. Pulmonary valve replacement (PVR) alleviates symptoms, normalizes right ventricular volumes, and improves ventricular function. Most studies addressing the role of PVR have examined older adolescents or adults. Less is known about the potential benefits of PVR in preadolescents with TOF and significant right ventricular dilatation. METHODS: We reviewed the clinical data for all preadolescents (< or = 13 years) with TOF who underwent cardiac magnetic resonance imaging (cMRI) or PVR, or both. Serial cMRI data were analyzed to determine the change in indexed right ventricular end-diastolic volume (RVEDV) and biventricular ventricular ejection fractions. Available cMRI data after PVR were compared with data before PVR. RESULTS: During the study period, 101 preadolescents with TOF had cMRI. The median age of complete repair was 6 months (range, 6 days to 3.4 years). The mean RVEDV at the first study was 135 +/- 39 mL/m(2). For 32 with serial cMRI studies, the RVEDV increased at a mean yearly rate of 9 mL/m(2). Ventricular systolic function was impaired in 46 (46%). Forty-two patients underwent PVR at a mean age of 8 +/- 3 years. No hospital deaths occurred, and no pulmonary valve reinterventions have been required. CONCLUSIONS: Significant right ventricular dilatation is common in preadolescents after transannular patch repair of TOF. Routine follow-up of this population should incorporate cMRI. Further studies will be needed to determine whether a strategy of early PVR might improve intermediate-term outcome.
Assuntos
Implante de Prótese de Valva Cardíaca/métodos , Insuficiência da Valva Pulmonar/cirurgia , Tetralogia de Fallot/cirurgia , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Insuficiência da Valva Pulmonar/diagnóstico , Insuficiência da Valva Pulmonar/fisiopatologia , Estudos Retrospectivos , Volume Sistólico , Tetralogia de Fallot/diagnóstico , Tetralogia de Fallot/fisiopatologia , Resultado do TratamentoAssuntos
Prótese Vascular , Meios de Contraste , Técnica de Fontan/instrumentação , Gadolínio , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Angiografia por Ressonância Magnética , Compostos Organometálicos , Pré-Escolar , Humanos , Síndrome do Coração Esquerdo Hipoplásico/diagnóstico , Masculino , Valor Preditivo dos TestesRESUMO
OBJECTIVES: Our goal was to determine flow distribution in the cavopulmonary connections of patients with and without bilateral superior venae cavae who had the Fontan procedure. No large series exists that establishes the flow distributions in Fontan patients, which would be an important resource for everyday clinical use and may affect future surgical reconstruction. METHODS: We studied 105 Fontan patients (aged 2-24 years) with through-plane phase contrast velocity mapping to determine flow rates in the inferior and superior venae cavae and left and right pulmonary arteries. Superior caval anastomosis type included 40 bidirectional Glenn shunts (of which 15 were bilateral) and 53 hemi-Fontan anastomoses; Fontan type included 69 intra-atrial baffles, 28 extracardiac conduits, and 4 atriopulmonary connections. RESULTS: Total caval flow was 2.9 +/- 1.0 L x min(-1) x m(-2), with an inferior vena cava contribution of 59% +/- 15%. Total pulmonary flow was 2.5 +/- 0.8 L x min(-1) x m(-2), statistically less than caval flow and not explained by fenestration presence. The right pulmonary artery contribution (55% +/- 13%) was statistically greater than the left. In patients with bilateral superior cavae, the right cava accounted for 52% +/- 14% of the flow, with no difference in pulmonary flow splits (50% +/- 16% to the right). Age and body surface area correlated with percent inferior caval contribution (r = 0.60 and 0.74, respectively). Superior vena cava anastomosis and Fontan type did not significantly affect pulmonary flow splits. CONCLUSIONS: Total Fontan cardiac index was 2.9 L x min(-1) x m(-2), with normal pulmonary flow splits (55% to the right lung). Inferior vena caval contribution to total flow increases with body surface area and age, consistent with data from healthy children.
Assuntos
Velocidade do Fluxo Sanguíneo , Técnica de Fontan , Imageamento por Ressonância Magnética , Artéria Pulmonar/fisiopatologia , Veias Cavas/fisiopatologia , Adolescente , Adulto , Aorta , Superfície Corporal , Criança , Pré-Escolar , Cardiopatias Congênitas/cirurgia , Humanos , Artéria Pulmonar/cirurgia , Fluxo Sanguíneo Regional , Veias Cavas/cirurgia , Adulto JovemRESUMO
BACKGROUND: Echocardiographic assessment of left ventricular (LV) contractility and dimensions is important in the management of patients with congenital heart disease. Conventional two-dimensional measures are limited because of volume or pressure-overloaded right ventricles that may distort the septal planes. Real-time three-dimensional echocardiography (RT3DE) has overcome these limitations; however, postprocessing image reconstruction and analysis are required. We compared LV indices calculated by new online RT3DE software with those obtained by magnetic resonance imaging (MRI) in patients with congenital heart disease. METHODS: Twelve patients (ages 1-33 years, median age = 15.9 years) with congenital heart disease underwent RT3DE and cardiac MRI. End-diastolic and end-systolic LV volumes, stroke volume, ejection fraction, and mass were calculated online using biplane method-of-discs and semiautomated border detection echocardiographic techniques. RESULTS: All RT3DE volumes correlated strongly with MRI (r = 0.93-0.99, P < .001). Ejection fraction had a lower correlation (r = 0.69, P = .013). There was no significant underestimation or overestimation of MRI values by RT3DE. Both biplane method-of-discs and semiautomated border detection echocardiographic techniques had excellent volume correlation (r = 0.94-0.99, P < .001). Interobserver variability was 7%. CONCLUSIONS: Combined RT3DE acquisition and analysis machines can accurately assess the LV in patients with congenital heart disease, thus impacting clinical management and perhaps obviating the need for MRI in some cases.
Assuntos
Ecocardiografia Tridimensional , Cardiopatias Congênitas/diagnóstico por imagem , Ventrículos do Coração , Imageamento por Ressonância Magnética , Função Ventricular Esquerda/fisiologia , Adolescente , Algoritmos , Criança , Feminino , Cardiopatias Congênitas/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Software , Volume SistólicoRESUMO
Particle image velocimetry (PIV) and phase contrast magnetic resonance imaging (PC-MRI) have not been compared in complex biofluid environments. Such analysis is particularly useful to investigate flow structures in the correction of single ventricle congenital heart defects, where fluid dynamic efficiency is essential. A stereolithographic replica of an extracardiac total cavopulmonary connection (TCPC) is studied using PIV and PC-MRI in a steady flow loop. Volumetric two-component PIV is compared to volumetric three-component PC-MRI at various flow conditions. Similar flow structures are observed in both PIV and PC-MRI, where smooth flow dominates the extracardiac TCPC, and superior vena cava flow is preferential to the right pulmonary artery, while inferior vena cava flow is preferential to the left pulmonary artery. Where three-component velocity is available in PC-MRI studies, some helical flow in the extracardiac TCPC is observed. Vessel cross sections provide an effective means of validation for both experiments, and velocity magnitudes are of the same order. The results highlight similarities to validate flow in a complex patient-specific extracardiac TCPC. Additional information obtained by velocity in three components further describes the complexity of the flow in anatomic structures.
Assuntos
Velocidade do Fluxo Sanguíneo , Técnica de Fontan/métodos , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/cirurgia , Ventrículos do Coração/anormalidades , Ventrículos do Coração/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Modelos Cardiovasculares , Simulação por Computador , Ventrículos do Coração/cirurgia , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do TratamentoRESUMO
BACKGROUND: During primary coarctation repair, collateral blood vessels contribute significantly to distal perfusion. We sought to determine if velocity-encoded cine magnetic resonance imaging (VENC-MRI) could provide insight into anatomy and hemodynamics of collateral flow in patients with unrepaired coarctation. METHODS: Sixteen patients (median age, 6.2 years; range, 1 to 18) with discrete coarctation (65% severe, 29% mild-moderate) and 10 controls (median age, 12.0 years; range, 9 to 15) without left-sided heart lesions were referred for cardiac MRI. Flow volumes were calculated from VENC-MRI images at the coarctation (proximal), diaphragm (distal), and midway between the two points (midpoint). A means model, repeated-measure analysis, was performed for volumes. RESULTS: In coarctation patients, flow volumes increased by 59% (p = 0.0002) from coarctation to diaphragm, primarily between the proximal and midpoint sites (by 77%, p < 0.0001). In controls, flow volumes decreased by 11% along the entire aortic study length. Coarctation volumes were lower than controls by 54% (p = 0.0003) at the proximal site but showed no statistical difference at the midpoint or diaphragm. CONCLUSIONS: Coarctation flow volumes maximally increase in the upper thoracic aorta, but approach normal flow volumes in the lower thoracic region. Arteries arising from mid and lower thoracic level, such as those supplying the anterior spinal cord, may have nearly normal flow if collaterals are present. Velocity-encoded MRI can evaluate flow in patients who have poor collateral circulation to improve surgical planning and decrease neurologic complications of coarctation repair.