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OBJECTIVES: To compare the repeatability and interrelation of various late gadolinium enhancement (LGE) assessment techniques for monitoring fibrotic changes in myocarditis follow-up. MATERIALS AND METHODS: LGE extent change between baseline and 3-month cardiovascular magnetic resonance (CMR) was compared in patients with acute myocarditis using the full width at half maximum (FWHM), gray-scale thresholds at 5 and 6 standard deviations (SD5 and SD6), visual assessment with threshold (VAT) and full manual (FM) techniques. In addition, visual presence score (VPS), visual transmurality score (VTS), and a simplified visual change score (VCS) were assessed. Intraclass-correlation (ICC) was used to evaluate repeatability, and methods were compared using Spearman's correlation. RESULTS: Forty-seven patients (38 male, median age: 27 [IQR: 21; 38] years) were included. LGE extent change differed among quantitative techniques (p < 0.01), with variability in the proportion of patients showing LGE change during follow-up (FWHM: 62%, SD5: 74%, SD6: 66%, VAT: 43%, FM: 60%, VPS: 53%, VTS: 77%, VCS: 89%). Repeatability was highest with FWHM (ICC: 0.97) and lowest with SD5 (ICC: 0.89). Semiquantitative scoring had slightly lower values (VPS ICC: 0.81; VTS ICC: 0.71). VCS repeatability was excellent (ICC: 0.93). VPS and VTS correlated with quantitative techniques, while VCS was positively associated with VPS, VTS, VAT, and FM, but not with FWHM, SD5, and SD6. CONCLUSION: FWHM offers the least observer-dependent LGE follow-up after myocarditis. VPS, VTS, and VCS are practical alternatives, showing reliable correlations with quantitative methods. Classification of patients exhibiting either stable or changing LGE relies on the assessment technique. CLINICAL RELEVANCE STATEMENT: This study shows that LGE monitoring in myocarditis is technique-dependent; the FWHM method yields the most consistent fibrotic tracking results, with scoring-based techniques as reliable alternatives. KEY POINTS: Recognition of fibrotic changes during myocarditis follow-up is significantly influenced by the choice of the quantification technique employed. The FWHM technique ensures highly repeatable tracking of myocarditis-related LGE changes. Segment-based visual scoring and the simplified visual change score offer practical, reproducible alternatives in resource-limited settings.
ABSTRACT
PURPOSE: Numerous electrocardiogram (ECG) abnormalities and late gadolinium enhancement (LGE) in cardiac magnetic resonance imaging (CMR) have been related to poor prognosis in acute myocarditis. We evaluated whether ECG parameters are associated with the distribution and dynamic of LGE along the course of myocarditis. METHODS: Fifty-one patients with CMR confirmed acute myocarditis were included who underwent CMR with LGE and 12-lead ECG at baseline and 3-month follow-up at our institution. The association between the presence, regional distribution and change of ECG parameters and LGE was investigated using linear regression analysis. LGE was quantified as visual presence score (VPS) and visual transmurality score (VTS). RESULTS: Among many ECG parameters only > 1 mm ST-elevation (STE) was associated with VPS and VTS at baseline (ß = 3.08 [95%CI: 1.75; 4.41], p = < 0.001 and ß = 5.40 [95%CI: 1.92; 8.88], p = 0.004; respectively). STE was most frequent in lateral and inferior ECG-leads (48% and 31%) and it was associated with VPS and VTS in these localizations (p < 0.05 all), however no association between anterior-septal STE and LGE could be confirmed. At follow-up the regression of STE was associated with the regression of VPS and VTS in univariate analysis (ß=-1.49 [95%CI: -2.41; -0.57], p = 0.003 and ß=-4.87 [95%CI: -7.18; -2.56], p = 0.001, respectively), which remained significant for VTS using a multivariate model (ß=-2.39 [95%CI: -3.32; -0.47], p = 0.019). CONCLUSION: Although we demonstrated some promising associations between STE and LGE, the usability of ECG to estimate the territorial involvement and dynamical changes of LGE along the course of myocarditis is generally limited and cardiac magnetic resonance should be considered for this purpose.
Subject(s)
Myocarditis , Humans , Myocarditis/pathology , Contrast Media , Gadolinium , Magnetic Resonance Imaging, Cine/methods , Predictive Value of Tests , Electrocardiography/methods , Arrhythmias, CardiacABSTRACT
This paper presents a generic method to enhance performance and incorporate temporal information for cardiorespiratory-based sleep stage classification with a limited feature set and limited data. The classification algorithm relies on random forests and a feature set extracted from long-time home monitoring for sleep analysis. Employing temporal feature stacking, the system could be significantly improved in terms of Cohen's κ and accuracy. The detection performance could be improved for three classes of sleep stages (Wake, REM, Non-REM sleep), four classes (Wake, Non-REM-Light sleep, Non-REM Deep sleep, REM sleep), and five classes (Wake, N1, N2, N3/4, REM sleep) from a κ of 0.44 to 0.58, 0.33 to 0.51, and 0.28 to 0.44 respectively by stacking features before and after the epoch to be classified. Further analysis was done for the optimal length and combination method for this stacking approach. Overall, three methods and a variable duration between 30 s and 30 min have been analyzed. Overnight recordings of 36 healthy subjects from the Interdisciplinary Center for Sleep Medicine at Charité-Universitätsmedizin Berlin and Leave-One-Out-Cross-Validation on a patient-level have been used to validate the method.Clinical relevance- The method can be employed generically to feature sets for (small scale) datasets to improve classification performance for classification problems with temporal relations with random forest classifiers.
Subject(s)
Sleep Stages , Sleep , Algorithms , Healthy Volunteers , Humans , Sleep, REMABSTRACT
AIMS: Late gadolinium enhancement (LGE) visualizes scar tissue after myocardial infarction. However, in clinically used LGE sequences, subendocardial infarcts can be missed due to low contrast between blood pool and subendocardium. The purpose of his study was to compare scar visibility in a novel 3-dimensional (3D) single breath-hold inversion recovery sequence with fixed, short inversion time (TI = 100 milliseconds) (short LGE) and standard 3D LGE imaging with individually adjusted TI (LGE). METHODS: Short LGE and LGE (both sequences with the same settings: spatial resolution, 1.2 × 1.2 mm; slice thickness, 8 mm; field of view, 350 × 350 mm; single breath-hold) were acquired in 64 patients with previous MI (13 female; mean age, 57 ± 19 years) at 1.5 T. Inversion time was set to 100 milliseconds in short LGE and adjusted individually in LGE according to the Look-Locker sequence. Two independent readers evaluated 1088 segments (17-segment model), identified infarcted segments, and categorized scar visibility (5 = excellent, 1 = poor scar visibility) and scar transmurality (4 = transmural, 0 = no scar) using a 5-point Likert scale. Signal intensity ratios between short LGE and LGE for scar and blood pool, for scar and remote myocardium, and for remote myocardium and blood pool were calculated. RESULTS: Short LGE showed 197 infarcted segments out of 1088 (18.1%); LGE revealed 191 segments (17.6%). Short LGE with dark scar and bright blood pool demonstrated better overall scar visibility, especially in subendocardially infarcted segments compared with LGE (4.2 vs 3.0, 5 = excellent visibility; P = 0.01). Signal intensity ratios for short LGE relative to LGE were 1.42 for scar/blood pool, 0.8 for scar/remote myocardium, and 0.22 for remote myocardium/blood.Overall transmurality was not rated higher in short LGE compared with LGE (P = 0.8). More fibrous tissue and total fibrous percentage (P = 0.04) were measured in short LGE compared with LGE, whereas myocardial mass was not significantly different (P = 0.5). Acquisition time was similar between short LGE and LGE (26 ± 4 seconds vs 25 ± 9 seconds, P = 0.7). CONCLUSIONS: Short LGE is a fast, single breath-hold 3D LGE sequence with no need for myocardial nulling due to fixed inversion time with improved scar visibility, especially in subendocardial infarcts.
Subject(s)
Cicatrix/diagnostic imaging , Heart/diagnostic imaging , Magnetic Resonance Imaging, Cine/methods , Myocardial Infarction/diagnostic imaging , Breath Holding , Contrast Media , Female , Gadolinium , Humans , Imaging, Three-Dimensional , Male , Middle Aged , Reproducibility of Results , Retrospective StudiesABSTRACT
To investigate whether image reconstruction with iterative reconstruction (IR) affects aortic valve calcification (AVC) scoring and likelihood categorization of severe aortic stenosis (AS). In this IRB-approved retrospective study, we included 100 consecutive patients with AS (40 females; mean age 77 ± 10 years; age range: 36-99 years) undergoing CT prior to transcatheter aortic valve replacement. Non-enhanced, electrocardiography-gated CT of the heart was reconstructed with filtered back projection (FBP) and with advanced modeled IR at strength levels 1-5. AVC Agatston scores were calculated and gender-specific cut-off values for AS likelihood categorization were applied according to current European Society of Cardiology recommendations (from unlikely to very likely). Friedman test with post-hoc Bonferroni correction was applied to analyze interval- and ordinal-scaled data. Compared to FBP, each IR strength level produced significantly different AVC Agatston scores (p < 0.001-0.002). Median AVC Agatston score for image reconstruction with FBP was 2527 (IQR: 1711-3663) and decreased with increasing IR strength levels up to 2281 (IQR: 1471-3357) at strength level 5. Likelihood categorization of severe AS was significantly different among image reconstruction algorithms (p < 0.001). Image reconstruction with IR strength level 5 led to a downward shift of likelihood categorization in 28 patients (28%) compared to images reconstructed with FBP. IR significantly impacts AVC scoring with significantly decreasing AVC scores with increasing IR strength levels. This leads to relevant changes in likelihood categorization of patients with severe AS., leading to underestimation of severe AS.
Subject(s)
Algorithms , Aortic Valve Stenosis/diagnostic imaging , Aortic Valve/diagnostic imaging , Aortic Valve/pathology , Calcinosis/diagnostic imaging , Multidetector Computed Tomography , Radiographic Image Interpretation, Computer-Assisted , Adult , Aged , Aged, 80 and over , Aortic Valve/physiopathology , Aortic Valve/surgery , Aortic Valve Stenosis/physiopathology , Aortic Valve Stenosis/surgery , Calcinosis/physiopathology , Calcinosis/surgery , Cardiac-Gated Imaging Techniques , Electrocardiography , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Retrospective Studies , Severity of Illness Index , Transcatheter Aortic Valve ReplacementABSTRACT
Esta pesquisa objetivou compreender o perfil e discurso do usuário de academias ao ar livre no município de Castanhal. Esta é uma pesquisa qualitativa, tendo como instrumento de pesquisa um questionário estruturado. A pesquisa foi dividida em duas grandes etapas, sendo elas: 1- visita in loco com aplicação do questionário estruturado e do termo de livre consentimento; 2- analise dos dados coletado. A primeira etapa ocorreu nos meses de setembro e outubro de 2017. Os pontos de coleta de dados foram a Praça do Estrela e a Praça da Bíblia, tendo sido entrevistados 15 pessoas em cada praça, totalizando 30 entrevistados. Dentre os resultados obtidos temse que 70% dos usuários das AAL entrevistados são do sexo feminino, e que estes entrevistados apresentam idade média de 48,83 anos. Mais de 53% (exatamente 53,33%) estão com sobrepeso e mais de 26% estão com obesidade. É unanime o discurso de que o projeto contribui para a interação social, onde muitos dos usuários criaram laços de amizade entre si, buscando ajudar-se na realização dos exercícios e motivar para não se ausentarem das AAL. Conclui-se que as AAL em Castanhal tem grande importância, tanto para oportunizar a realização de atividades físicas pela população, bem como serem espaços de relações sociais.
This research aimed to understand the profile and discourse of the user of outdoor gyms in the municipality of Castanhal. This is a qualitative research, having as a research instrument a structured questionnaire. The research was divided into two main stages, namely: 1 - on - site visit, application of the structured questionnaire and free consent term; 2- Analysis of the data collected. The first stage occurred in September and October 2017. Data collection points were Praça do Estrela and Praça da Biblia, and 15 people were interviewed in each square, totaling 30 respondents. Among the results obtained, 70% of the AAL users interviewed are female, and that these interviewees have a mean age of 48.83 years. More than 53% (exactly 53.33%) are overweight and more than 26% are obese. It is unanimous the discourse that the project contributed to social interaction, where many of the users created bonds of friendship with each other, seeking to help in the accomplishment of the exercises and motivate not to be absent from AAL. It is concluded that the AAL in Castanhal is of great importance, both to provide opportunities for physical activities by the population, as well as spaces of social relations.
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Humans , Adult , Quality of Life , Socialization , Socioeconomic Factors , Exercise , Urban Area , Qualitative Research , Health Promotion , Leisure ActivitiesABSTRACT
Shiga toxin subunit B (STxB) binding to its cellular receptor Gb3 leads to the formation of protein-lipid clusters and bending of the membrane. A newly developed synthetic route allowed synthesizing the biologically most relevant Gb3-C24:1 2OH species with both, the natural (Gb3-R) as well as the unnatural (Gb3-S) configuration of the 2OH group. The derivatives bind STxB with identical nanomolar affinity, while the propensity to induce membrane tubules in giant unilamellar vesicles is more pronounced for Gb3-S. Fluorescence and atomic force microscopy images of phase-separated supported membranes revealed differences in the lateral organization of the protein on the membrane. Gb3-R favorably induces large and tightly packed protein clusters, while a lower protein density is found on Gb3-S doped membranes.