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1.
Zhonghua Xin Xue Guan Bing Za Zhi ; 48(11): 922-929, 2020 Nov 24.
Artigo em Chinês | MEDLINE | ID: mdl-33210863

RESUMO

Objective: To investigate the distribution pattern of late gadolinium enhancement (LGE) in left ventricular free wall of patients with dilated cardiomyopathy (DCM). Methods: A total of 130 consecutive DCM patients who were hospitalized in our hospital, underwent both CMR and CTA examinations and met the inclusion and exclusion criteria including negative results of coronary angiography or coronary CTA, were retrospective included in this study. The LGE pattern, extent and distribution in left ventricular free wall were analyzed. Results: Left ventricular free wall LGE was detected in 56 out of 130 DCM patients. LGE was observed in both septal and free wall in 53 out of 56 patients with LGE (94.6%). Prevalence of NYHA classification Ⅲ/Ⅳ, intraventricular block, paroxysmal ventricular tachycardia, and secondary mitral insufficiency was significantly higher, while left ventricular ejection fraction was significantly lower, left ventricular end-diastolic/systolic volume, left ventricular end-diastolic/systolic volume index and left ventricular end-diastolic diameters values were larger in patients with LGE than without LGE (all P<0.05). In terms LGE pattern among these 56 patients, percent of involved myocardial segments in patients with subepicardial LGE (n=19) was significantly higher than patients with intermural LGE (n=30), patients with transmural LGE (n=21), and patients with subendocardial LGE (n=9)(60.8%(127/209) vs. 32.4%(107/330), 32.5%(75/231), 26.3%(26/99), respectively, all P < 0.01). Transmural LGE was most likely to involve the left ventricular inferior lateral basal (18/21) and mid (13/21) segment, followed by anterior lateral basal (15/21) and mid (11/21) segments and inferior mid segment (9/21). Subepicardial LGE was more likely to occur in the inferior lateral basal (13/19) and mid (16/19) segment, anterior lateral basal (13/19) and mid (15/19) segment, anterior lateral basal (13/19) and mid (15/19) segment, lateral apical (13/19), anterior and inferior mid segment (12/19 and 10/19), and apical segment (15/19 and 10/19). Intermural LGE mostly involved the anterior and inferior basal (19/30, 16/30) and mid (18/30 and 14/30) segment. There were 33 cases of single LGE pattern and 23 cases of multiple LGE pattern. Percent of involved myocardial segments was significantly higher in multiple LGE group than single LGE group (60.9% (154/253) vs. 49.9%(181/363), P = 0.007). Of 130 patients, 23 received heart transplantation, of which 6 patients had septal LGE alone and 17 patients had septal and free wall LGE. The rate of heart transplantation in the latter group was higher (32.1% (17/53)vs. 13.6%(6/44), P=0.034). Conclusions: There are several LGE distribution patterns in left ventricular wall among DCM patients.


Assuntos
Cardiomiopatia Dilatada , Meios de Contraste , Cardiomiopatia Dilatada/diagnóstico por imagem , Gadolínio , Humanos , Imagem Cinética por Ressonância Magnética , Valor Preditivo dos Testes , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1174-1177, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018196

RESUMO

Cardiac magnetic resonance (MR) tissue tagging offers an excellent solution for tracking deformation and is considered the reference standard for the quantification of strain. However, due to the requirements for a dedicated acquisition sequence and post-processing software, tagged MR acquisitions are performed much less frequently in routine clinical practice than the anatomical cine MR sequence. Using tagged MR as the reference standard, this study proposes an approach to evaluate a diffeomorphic image registration algorithm applied on cine MR images to compute the cardiac deformation. In contrast to previous evaluation methods that compared the final results, such as strain, computed from cine and tagged MR sequences, the proposed method performs a direct frame-to-frame comparison in the evaluation. To overcome the problem of misalignment between the tagged and cine MR images, the proposed approach performs transformations to and from the two-dimensional image pixel coordinates and three-dimensional space using the meta-information encoded in the MR images. Linear temporal interpolation is performed using the frame acquisition time since the last R-wave peak value of the electrocardiogram signal recorded in the meta-information. Several statistic measures are computed and reported for the registration error using the Euclidean distances between the corresponding set of points obtained using cine and tagged MR images.


Assuntos
Interpretação de Imagem Assistida por Computador , Imagem Cinética por Ressonância Magnética , Proteínas de Transporte , Citocinas , Coração/diagnóstico por imagem , Espectroscopia de Ressonância Magnética
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1178-1181, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018197

RESUMO

To date, regional atrial strains have not been imaged in vivo, despite their potential to provide useful clinical information. To address this gap, we present a novel CINE MRI protocol capable of imaging the entire left atrium at an isotropic 2-mm resolution in one single breath-hold. As proof of principle, we acquired data in 10 healthy volunteers and 2 cardiovascular patients using this technique. We also demonstrated how regional atrial strains can be estimated from this data following a manual segmentation of the left atrium using automatic image tracking techniques. The estimated principal strains vary smoothly across the left atrium and have a similar magnitude to estimates reported in the literature.


Assuntos
Átrios do Coração , Imagem Cinética por Ressonância Magnética , Suspensão da Respiração , Átrios do Coração/diagnóstico por imagem , Humanos
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1198-1202, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018202

RESUMO

Atrial fibrillation (AF) is the most common sustained arrhythmia and is associated with dramatic increases in mortality and morbidity. Atrial cine MR images are increasingly used in the management of this condition, but there are few specific tools to aid in the segmentation of such data. Some characteristics of atrial cine MR (thick slices, variable number of slices in a volume) preclude the direct use of traditional segmentation tools. When combined with scarcity of labelled data and similarity of the intensity and texture of the left atrium (LA) to other cardiac structures, the segmentation of the LA in CINE MRI becomes a difficult task. To deal with these challenges, we propose a semi-automatic method to segment the left atrium (LA) in MR images, which requires an initial user click per volume. The manually given location information is used to generate a chamber location map to roughly locate the LA, which is then used as an input to a deep network with slightly over 0.5 million parameters. A tracking method is introduced to pass the location information across a volume and to remove unwanted structures in segmentation maps. According to the results of our experiments conducted in an in-house MRI dataset, the proposed method outperforms the U-Net [1] with a margin of 20 mm on Hausdorff distance and 0.17 on Dice score, with limited manual interaction.


Assuntos
Fibrilação Atrial , Processamento de Imagem Assistida por Computador , Fibrilação Atrial/diagnóstico por imagem , Átrios do Coração/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Imagem Cinética por Ressonância Magnética
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1217-1220, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018206

RESUMO

In this work, we implement a fully convolutional segmenter featuring both a learned group structure and a regularized weight-pruner to reduce the high computational cost in volumetric image segmentation. We validated our framework on the ACDC dataset featuring one healthy and four pathology patient groups imaged throughout the cardiac cycle. Our technique achieved Dice scores of 96.8% (LV blood-pool), 93.3% (RV blood-pool), and 90.0% (LV Myocardium) with five-fold cross-validation and yielded similar clinical parameters as those estimated from the ground-truth segmentation data. Based on these results, this technique has the potential to become an efficient and competitive cardiac image segmentation tool that may be used for cardiac computer-aided diagnosis, planning, and guidance applications.


Assuntos
Imagem Cinética por Ressonância Magnética , Redes Neurais de Computação , Algoritmos , Coração/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1221-1224, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018207

RESUMO

Cardiovascular magnetic resonance imaging (CMRI) is one of the most accurate non-invasive modalities for evaluation of cardiac function, especially the left ventricle (LV). In this modality, the manual or semi-automatic delineation of LV by experts is currently the standard clinical practice for chambers segmentation. Despite these efforts, global quantification of LV remains a challenge. In this work, a combination of two convolutional neural network (CNN) architectures for quantitative evaluation of the LV is described, which estimates the cavity and the myocardium areas, endocardial cavity dimensions in three directions, and the myocardium regional wall thickness in six radial directions. The method was validated in CMRI exams of 56 patients (LVQuan19 dataset) and evaluated by metrics Dice Index, Mean Absolute Error, and Correlation with superior performance compared to the state-of-the-art methods. The combination of the CNN architectures provided a simpler yet fully automated approach, requiring no specialist interaction.Clinical Relevance- With the proposed method, it is possible to perform automatically the full quantification of regional clinically relevant parameters of the left ventricle in short-axis CMRI images with superior performance compared to state-of-the-art methods.


Assuntos
Imagem Cinética por Ressonância Magnética , Redes Neurais de Computação , Endocárdio , Ventrículos do Coração/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética
9.
Nat Commun ; 11(1): 4992, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020487

RESUMO

Prenatal detection of congenital heart disease facilitates the opportunity for potentially life-saving care immediately after the baby is born. Echocardiography is routinely used for screening of morphological malformations, but functional measurements of blood flow are scarcely used in fetal echocardiography due to technical assumptions and issues of reliability. Magnetic resonance imaging (MRI) is readily used for quantification of abnormal blood flow in adult hearts, however, existing in utero approaches are compromised by spontaneous fetal motion. Here, we present and validate a novel method of MRI velocity-encoding combined with a motion-robust reconstruction framework for four-dimensional visualization and quantification of blood flow in the human fetal heart and major vessels. We demonstrate simultaneous 4D visualization of the anatomy and circulation, which we use to quantify flow rates through various major vessels. The framework introduced here could enable new clinical opportunities for assessment of the fetal cardiovascular system in both health and disease.


Assuntos
Coração Fetal/diagnóstico por imagem , Coração Fetal/fisiologia , Tomografia Computadorizada Quadridimensional/métodos , Imagem Cinética por Ressonância Magnética/métodos , Velocidade do Fluxo Sanguíneo , Vasos Sanguíneos/diagnóstico por imagem , Vasos Sanguíneos/fisiologia , Feminino , Idade Gestacional , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/fisiopatologia , Humanos , Imagens de Fantasmas , Gravidez , Diagnóstico Pré-Natal
10.
Radiol Med ; 125(11): 1124-1134, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33025305

RESUMO

Myocarditis is an inflammatory disease of the heart muscle, diagnosed by histological, immunological, and immunohistochemical criteria. Endomyocardial biopsy represents the diagnostic gold standard for its diagnosis but is infrequently used. Due to its noninvasive ability to detect the presence of myocardial edema, hyperemia and necrosis/fibrosis, Cardiac MR imaging is routinely used in the clinical practice for the diagnosis of acute myocarditis. Recently pixel-wise mapping of T1 and T2 relaxation time have been introduced into the clinical Cardiac MR protocol increasing its accuracy. Our paper will review the role of MR imaging in the diagnosis of acute myocarditis.


Assuntos
Técnicas de Imagem Cardíaca/métodos , Endocárdio/patologia , Imagem por Ressonância Magnética/métodos , Miocardite/diagnóstico por imagem , Doença Aguda , Adulto , Doenças Assintomáticas , Betacoronavirus , Bioprospecção , Doença Crônica , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Miocardite/etiologia , Miocardite/patologia , Pandemias , Pericardite/diagnóstico por imagem , Pericardite/etiologia , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Prognóstico
11.
J Cardiovasc Magn Reson ; 22(1): 62, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32878630

RESUMO

BACKGROUND: Intensive endurance exercise may induce a broad spectrum of right ventricular (RV) adaptation/remodelling patterns. Late gadolinium enhancement (LGE) has also been described in cardiovascular magnetic resonance (CMR) of some endurance athletes and its clinical meaning remains controversial. Our aim was to characterize the features of contrast CMR and the observed patterns of the LGE distribution in a cohort of highly trained endurance athletes. METHODS: Ninety-three highly trained endurance athletes (> 12 h training/week at least during the last 5 years; 36 ± 6 years old; 53% male) and 72 age and gender-matched controls underwent a resting contrast CMR. In a subgroup of 28 athletes, T1 mapping was also performed. RESULTS: High endurance training load was associated with larger bi-ventricular and bi-atrial sizes and a slight reduction of biventricular ejection fraction, as compared to controls in both genders (p < 0.05). Focal LGE was significantly more prevalent in athletes than in healthy subjects (37.6% vs 2.8%; p < 0.001), with a typical pattern in the RV insertion points. In T1 mapping, those athletes who had focal LGE had higher extracellular volume (ECV) at the remote myocardium than those without (27 ± 2.2% vs 25.2 ± 2.1%; p < 0.05). CONCLUSIONS: Highly trained endurance athletes showed a ten-fold increase in the prevalence of focal LGE as compared to control subjects, always confined to the hinge points. Additionally, those athletes with focal LGE demonstrated globally higher myocardial ECV values. This matrix remodelling and potential presence of myocardial fibrosis may be another feature of the athlete's heart, of which the clinical and prognostic significance remains to be determined.


Assuntos
Atletas , Cardiomegalia Induzida por Exercícios , Meios de Contraste/administração & dosagem , Coração/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Compostos Organometálicos/administração & dosagem , Resistência Física , Função Ventricular Direita , Remodelação Ventricular , Adaptação Fisiológica , Adulto , Estudos de Casos e Controles , Feminino , Fibrose , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Valor Preditivo dos Testes , Volume Sistólico , Função Ventricular Esquerda , Adulto Jovem
12.
Pediatr Clin North Am ; 67(5): 821-842, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32888684

RESUMO

Left-to-right shunts represent a significant portion of congenital heart disease. Such lesions are common in isolation, but are frequently seen in conjunction with other, often more complex, congenital heart disease. This review covers basic anatomy, physiology, physical examination findings, diagnosis and management for atrial septal defects, ventricular septal defects, and patent ductus arteriosa.


Assuntos
Ecocardiografia/métodos , Forame Oval Patente/diagnóstico , Comunicação Interatrial/diagnóstico , Imagem Cinética por Ressonância Magnética/métodos , Criança , Humanos
13.
J Cardiovasc Magn Reson ; 22(1): 64, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32892749

RESUMO

BACKGROUND: Pediatric cancer survivors are at increased risk of cardiac dysfunction and heart failure. Reduced peak oxygen consumption (peak VO2) is associated with impaired cardiac reserve (defined as the increase in cardiac function from rest to peak exercise) and heart failure risk, but it is unclear whether this relationship exists in pediatric cancer survivors. This study sought to investigate the presence of reduced peak VO2 in pediatric cancer survivors with increased risk of heart failure, and to assess its relationship with resting cardiac function and cardiac haemodynamics and systolic function during exercise. METHODS: Twenty pediatric cancer survivors (8-24 years; 10 male) treated with anthracycline chemotherapy ± radiation underwent cardiopulmonary exercise testing to quantify peak VO2, with a value < 85% of predicted defined as impaired peak VO2. Resting cardiac function was assessed using 2- and 3-dimensional echocardiography, with cardiac reserve quantified from resting and peak exercise heart rate, stroke volume index (SVI) and cardiac index (CI) using exercise cardiovascular magnetic resonance (CMR). RESULTS: Twelve of 20 survivors (60%) had reduced peak VO2 (70 ± 16% vs. 97 ± 14% of age and gender predicted). There were no differences in echocardiographic or CMR measurements of resting cardiac function between survivors with normal or impaired peak VO2. However, those with reduced peak VO2 had diminished cardiac reserve, with a lesser increase in CI and SVI during exercise (Interaction P < 0.01 for both), whilst the heart rate response was similar (P = 0.71). CONCLUSIONS: Whilst exercise intolerance is common among pediatric cancer survivors, it is poorly explained by resting measures of cardiac function. In contrast, impaired exercise capacity is associated with impaired haemodynamics and systolic functional reserve measured during exercise. Consequently, measures of cardiopulmonary fitness and cardiac reserve may aid in early identification of survivors with heightened risk of long-term heart failure.


Assuntos
Antraciclinas/efeitos adversos , Antibióticos Antineoplásicos/efeitos adversos , Sobreviventes de Câncer , Aptidão Cardiorrespiratória , Teste de Esforço , Tolerância ao Exercício , Cardiopatias/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Lesões por Radiação/diagnóstico por imagem , Adolescente , Fatores Etários , Cardiotoxicidade , Criança , Feminino , Nível de Saúde , Cardiopatias/induzido quimicamente , Cardiopatias/fisiopatologia , Hemodinâmica , Humanos , Masculino , Consumo de Oxigênio , Valor Preditivo dos Testes , Lesões por Radiação/etiologia , Lesões por Radiação/fisiopatologia , Radioterapia/efeitos adversos , Fatores de Risco , Adulto Jovem
14.
J Cardiovasc Magn Reson ; 22(1): 63, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32892751

RESUMO

BACKGROUND: Myocardial native T1 and T2 relaxation time mapping are sensitive to pathological increase of myocardial water content (e.g. myocardial edema). However, the influence of physiological hydration changes as a possible confounder of relaxation time assessment has not been studied. The purpose of this study was to evaluate, whether changes in myocardial water content due to dehydration and hydration might alter myocardial relaxation times in healthy subjects. METHODS: A total of 36 cardiovascular magnetic resonance (CMR) scans were performed in 12 healthy subjects (5 men, 25.8 ± 3.2 years). Subjects underwent three successive CMR scans: (1) baseline scan, (2) dehydration scan after 12 h of fasting (no food or water), (3) hydration scan after hydration. CMR scans were performed for the assessment of myocardial native T1 and T2 relaxation times and cardiac function. For multiple comparisons, repeated measures ANOVA or the Friedman test was used. RESULTS: There was no change in systolic blood pressure or left ventricular ejection fraction between CMR scans (P > 0.05, respectively). T1 relaxation times were significantly reduced with dehydration (987 ± 27 ms [baseline] vs. 968 ± 29 ms [dehydration] vs. 986 ± 28 ms [hydration]; P = 0.006). Similar results were observed for T2 relaxation times (52.9 ± 1.8 ms [baseline] vs. 51.5 ± 2.0 ms [dehydration] vs. 52.2 ± 1.9 ms [hydration]; P = 0.020). CONCLUSIONS: Dehydration may lead to significant alterations in relaxation times and thereby may influence precise, repeatable and comparable assessment of native T1 and T2 relaxation times. Hydration status should be recognized as new potential confounder of native T1 and T2 relaxation time assessment in clinical routine.


Assuntos
Composição Corporal , Coração/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Estado de Hidratação do Organismo , Função Ventricular Esquerda , Equilíbrio Hidroeletrolítico , Adulto , Desidratação , Diástole , Feminino , Voluntários Saudáveis , Coração/fisiologia , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Adulto Jovem
15.
J Cardiovasc Magn Reson ; 22(1): 66, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32921308

RESUMO

BACKGROUND: Cardiovascular magnetic resonance (CMR) late gadolinium enhancement (LGE) is a valuable technique for detecting myocardial disorders and fibrosis. However, we sometimes observe a linear, mid-wall high intensity signal in the basal septum in the short axis view, which often presents diagnostic difficulties in the clinical setting. The purpose of this study was to compare the linear, mid-wall high intensity in the basal septum identified by LGE with the anterior septal perforator arteries identified by coronary computed tomography angiography (CorCTA). METHODS: We retrospectively selected 148 patients who underwent both CorCTA and CMR LGE within 1 year. In the interpretation of LGE, we defined a positive linear high intensity (LHI+) as follows: ① LHI in the basal septum and ② observable for 1.5 cm or more. All other patients were defined as a negative LHI (LHI-). In LHI+ patients, we assessed the correlation between the LHI length and the septal perforator artery length on CorCTA. We also compared the length of the septal perforator artery on CorCTA between LHI+ patients and LHI- patients. RESULTS: A population of 111 patients were used for further analysis. Among these , there were 55 LHI+ patients and 56 LHI- patients. In LHI+ patients, linear regression analysis revealed that there was a good agreement between LGE LHI and septal perforator arteries by CorCTA in terms of length measurements. The measured length of the anterior septal perforator arteries was significantly shorter in LHI- patients than in LHI+ patients (10 ± 8 mm vs. 21 ± 8 mm; P < 0.05). CONCLUSIONS: The LHI observed in the basal septum on short axis LGE may reflect contrast enhancement of the anterior septal perforator arteries. It is important to interpret this septal LHI against knowledge of anatomic structure, to avoid misinterpretations of LGE and prevent misdiagnosis.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Meios de Contraste/administração & dosagem , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Gadolínio DTPA/administração & dosagem , Septos Cardíacos/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Isquemia Miocárdica/diagnóstico por imagem , Idoso , Artefatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos
16.
J Cardiovasc Magn Reson ; 22(1): 68, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32938483

RESUMO

BACKGROUND: Cardiovascular magnetic resonance (CMR) phase contrast (PC) flow measurements suffer from phase offset errors. Background subtraction based on stationary phantom measurements can most reliably be used to overcome this inaccuracy. Stationary tissue correction is an alternative and does not require additional phantom scanning. The aim of this study was 1) to compare measurements with and without stationary tissue correction to phantom corrected measurements on different GE Healthcare CMR scanners using different software packages and 2) to evaluate the clinical implications of these methods. METHODS: CMR PC imaging of both the aortic and pulmonary artery flow was performed in patients on three different 1.5 T CMR scanners (GE Healthcare) using identical scan parameters. Uncorrected, first, second and third order stationary tissue corrected flow measurement were compared to phantom corrected flow measurements, our reference method, using Medis QFlow, Circle cvi42 and MASS software. The optimal (optimized) stationary tissue order was determined per scanner and software program. Velocity offsets, net flow, clinically significant difference (deviation > 10% net flow), and regurgitation severity were assessed. RESULTS: Data from 175 patients (28 (17-38) years) were included, of which 84% had congenital heart disease. First, second and third order and optimized stationary tissue correction did not improve the velocity offsets and net flow measurements. Uncorrected measurements resulted in the least clinically significant differences in net flow compared to phantom corrected data. Optimized stationary tissue correction per scanner and software program resulted in net flow differences (> 10%) in 19% (MASS) and 30% (Circle cvi42) of all measurements compared to 18% (MASS) and 23% (Circle cvi42) with no correction. Compared to phantom correction, regurgitation reclassification was the least common using uncorrected data. One CMR scanner performed worse and significant net flow differences of > 10% were present both with and without stationary tissue correction in more than 30% of all measurements. CONCLUSION: Phase offset errors had a significant impact on net flow quantification, regurgitation assessment and varied greatly between CMR scanners. Background phase correction using stationary tissue correction worsened accuracy compared to no correction on three GE Healthcare CMR scanners. Therefore, careful assessment of phase offset errors at each individual scanner is essential to determine whether routine use of phantom correction is necessary. TRIAL REGISTRATION: Observational Study.


Assuntos
Aorta/diagnóstico por imagem , Insuficiência da Valva Aórtica/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico por imagem , Hemodinâmica , Interpretação de Imagem Assistida por Computador , Imagem Cinética por Ressonância Magnética/instrumentação , Artéria Pulmonar/diagnóstico por imagem , Insuficiência da Valva Pulmonar/diagnóstico por imagem , Adolescente , Adulto , Aorta/fisiopatologia , Insuficiência da Valva Aórtica/fisiopatologia , Velocidade do Fluxo Sanguíneo , Criança , Feminino , Cardiopatias Congênitas/fisiopatologia , Humanos , Masculino , Imagens de Fantasmas , Valor Preditivo dos Testes , Artéria Pulmonar/fisiopatologia , Insuficiência da Valva Pulmonar/fisiopatologia , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença , Adulto Jovem
17.
J Cardiovasc Magn Reson ; 22(1): 61, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32878639

RESUMO

The aim of this document is to provide specific recommendations on the use of cardiovascular magnetic resonance (CMR) protocols in the era of the COVID-19 pandemic. In patients without COVID-19, standard CMR protocols should be used based on clinical indication as usual. Protocols used in patients who have known / suspected active COVID-19 or post COVID-19 should be performed based on the specific clinical question with an emphasis on cardiac function and myocardial tissue characterization. Short and dedicated protocols are recommended.


Assuntos
Doenças Cardiovasculares/diagnóstico por imagem , Infecções por Coronavirus/prevenção & controle , Controle de Infecções/organização & administração , Imagem Cinética por Ressonância Magnética/normas , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Guias de Prática Clínica como Assunto , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pandemias/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Índice de Gravidade de Doença , Sociedades Médicas , Estados Unidos
18.
Radiol Med ; 125(11): 1040-1055, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32939626

RESUMO

Cardiac magnetic resonance (CMR) imaging is an effective method for noninvasively imaging the heart which in the last two decades impressively enhanced spatial and temporal resolution and imaging speed, broadening its spectrum of applications in cardiovascular disease. CMR imaging techniques are designed to noninvasively assess cardiovascular morphology, ventricular function, myocardial perfusion, tissue characterization, flow quantification and coronary artery disease. These intrinsic features yield CMR suitable for diagnosis, follow-up and longitudinal monitoring after treatment of cardiovascular diseases. The aim of this paper is to review the technical basis of CMR, from cardiac imaging planes to cardiac imaging sequences.


Assuntos
Coração/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Técnicas de Imagem Cardíaca/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Frequência Cardíaca , Humanos , Imageamento Tridimensional , Angiografia por Ressonância Magnética/métodos , Imagem Cinética por Ressonância Magnética/métodos , Contração Miocárdica , Imagem de Perfusão do Miocárdio , Técnicas de Imagem de Sincronização Respiratória , Fatores de Tempo
19.
Echocardiography ; 37(10): 1673-1677, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32986881

RESUMO

We report the case of a healthy 35-year-old woman who had experienced a flu-like syndrome during the week before childbirth and heart failure symptoms 10 days before the current hospitalization and presented to our emergency department with clinical signs of congestive heart failure, echocardiographic evidence of a severely dilated and hypokinetic heart, laboratory evidence of SARS-CoV-2 disease, and radiologic findings consistent with both virus-related pneumonia and heart failure. Early cardiac magnetic resonance was crucial for the diagnosis of postpartum cardiomyopathy and for the exclusion of virus-related myocarditis, allowing us to decide on a prudent and supportive clinical approach.


Assuntos
Betacoronavirus , Cardiomiopatias/diagnóstico , Infecções por Coronavirus/complicações , Eletrocardiografia/métodos , Miocardite/diagnóstico , Período Periparto , Pneumonia Viral/complicações , Complicações Cardiovasculares na Gravidez/diagnóstico , Doença Aguda , Adulto , Cardiomiopatias/epidemiologia , Comorbidade , Infecções por Coronavirus/epidemiologia , Diagnóstico Diferencial , Ecocardiografia , Feminino , Humanos , Imagem Cinética por Ressonância Magnética/métodos , Miocardite/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Gravidez , Tomografia Computadorizada por Raios X
20.
PLoS One ; 15(8): e0236570, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764748

RESUMO

PURPOSE/OBJECTIVES: Recently a 1.5 Tesla MR Linac has been FDA approved and is commercially available. Clinical series describing treatment methods and outcomes for upper abdominal tumors using a 1.5 Tesla MR Linac are lacking. We present the first clinical series of upper abdominal tumors treated using a 1.5 Tesla MR Linac along with the acquisition of intra-treatment quantitative imaging. MATERIALS/METHODS: 10 patients with abdominal tumors were treated at our institution. Each patient enrolled in an IRB approved advanced imaging protocol. Both daily real-time adaptive and non-adaptive methods were used, and selection criteria are described. Adaptive plans were based on pre-beam motion-averaged or mid-position images derived from respiratory-correlated 4D-MRI. Quantitative intravoxel incoherent motion diffusion-weighted imaging and T2 mapping were acquired during plan adaptation. Real-time motion monitoring using cine MRI was performed during beam-on. RESULTS: Median patient age was 68.2, five patients were female. Tumor types included liver metastatic lesions from melanoma and sarcoma, primary liver hepatocellular carcinoma (HCC), and regional abdominal tumors included pancreatic metastatic lesions from renal cell carcinoma (RCC) along with two cases of recurrent pancreatic cancer. Doses included 30 Gy in 6 fractions, 33 Gy in 5 fractions, 50 Gy in 5 fractions, 45 Gy in 3 fractions, and 60 Gy in 3 fractions, depending on the location and clinical circumstances. Treatments were feasible and were successfully completed in all patients without significant acute toxicity, technical complications, or need for back up CT based treatment plans. CONCLUSIONS: We present a first clinical series of patients treated for pancreatic tumors, primary liver tumors, and secondary liver tumors with a 1.5 Tesla MR Linear accelerator using adapt-to-position and adapt-to-shape strategies. Treatments were well tolerated by all patients. Acquisition of fully quantitative MR imaging was feasible during the course of the treatment delivery workflow without extending overall treatment times.


Assuntos
Neoplasias Hepáticas/radioterapia , Metástase Neoplásica/radioterapia , Neoplasias Pancreáticas/radioterapia , Aceleradores de Partículas , Radiocirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Planejamento da Radioterapia Assistida por Computador , Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada
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