Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Eur Radiol ; 31(4): 2132-2143, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33037914

RESUMO

OBJECTIVE: To assess the use of a volumetric image display simulation tool (VDST) for the evaluation of applied radiological neuroanatomy knowledge and spatial understanding of radiotherapy technologist (RTT) undergraduates. METHODS: Ninety-two third-year RTT students from three French RTT schools took an examination using software that allows visualization of multiple volumetric image series. To serve as a reference, 77 first- and second-year undergraduates, as well as ten senior neuroradiologists, took the same examination. The test included 13 very-short-answer questions (VSAQ) and 21 exercises in which examinees positioned markers onto preloaded brain MR images from a healthy volunteer. The response time was limited. Each correct answer scored 100 points, with a maximum possible test score of 3,400 (VSAQ = 1,300; marker exercise = 2,100). Answers were marked automatically for the marker positioning exercise and semi-automatically for the VSAQs against prerecorded expected answers. RESULTS: Overall, the mean test score was 1,787 (150-3,300) and the standard deviation was 781. Scores were highly significantly different between all evaluated groups (p < 0.001). The interoperator reproducibility was 0.90. All the evaluated groups could be discriminated by VSAQ, marker, and overall total scores independently (p ≤ 0.0001 to 0.001). The test was able to discriminate between the three schools either by VSAQ scores (p < 0.001 to 0.02) or by overall total score (p < 0.001 to 0.05). CONCLUSION: This software is a high-quality evaluation tool for the assessment of radiological neuroanatomy knowledge and spatial understanding in RTT undergraduates. KEY POINTS: • This VDST allows volumetric image analysis of MR studies. • A high reliability test could be created with this tool. • Test scores were strongly associated with the examinee expertise level.


Assuntos
Neuroanatomia , Navegação Espacial , Avaliação Educacional , Humanos , Neuroanatomia/educação , Reprodutibilidade dos Testes , Estudantes
2.
Eur J Nucl Med Mol Imaging ; 45(4): 549-557, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29159573

RESUMO

PURPOSE: The growth phases of medically treated abdominal aortic aneurysms (AAA) are frequently associated with an 18F-fluorodesoxyglucose positron emission tomography (FDG-PET) pattern involving low baseline and subsequent higher FDG uptake. However, the FDG-PET patterns associated with the endovascular aneurysm repair (EVAR) of larger AAA are presently unknown. This study aimed to investigate the relationship between serial AAA FDG uptake measurements, obtained before EVAR and 1 and 6 months post-intervention and subsequent sac shrinkage at 6 months, a well-recognized indicator of successful repair. METHODS: Thirty-three AAA patients referred for EVAR (maximal diameter: 55.4 ± 6.0 mm, total volume: 205.7 ± 63.0 mL) underwent FDG-PET/computed tomography (CT) before EVAR and at 1 and 6 months thereafter, with the monitoring of AAA volume and of a maximal standardized FDG uptake [SUVmax] averaged between the axial slices encompassing the AAA. RESULTS: Sac shrinkage was highly variable and could be stratified into three terciles: a first tercile in which shrinkage was absent or very limited (0-29 mL) and a third tercile with pronounced shrinkage (56-165 mL). SUVmax values were relatively low at baseline in the 1st tercile (SUVmax: 1.69 ± 0.33), but markedly increased at 6 months (2.42 ± 0.69, p = 0.02 vs. baseline). These SUV max values were by contrast much higher at baseline in the 3rd tercile (SUVmax: 2.53 ± 0.83 p = 0.009 vs. 1st tercile) and stable at 6 months (2.49 ± 0.80), while intermediate results were documented in the 2nd tercile. Lastly, the amount of sac shrinkage, expressed in absolute values or in percentages of baseline AAA volumes, was positively correlated with baseline SUVmax (p = 0.001 for both). CONCLUSION: A low pre-EVAR FDG uptake and increased AAA FDG uptake at 6 months are associated with reduced sac shrinkage. This sequential FDG-PET pattern is similar to that already shown to accompany growth phases of medically treated AAA.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico por imagem , Procedimentos Endovasculares , Tomografia por Emissão de Pósitrons , Aorta , Aneurisma da Aorta Abdominal/cirurgia , Fluordesoxiglucose F18 , Humanos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
3.
J Cardiovasc Magn Reson ; 19(1): 2, 2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-28063459

RESUMO

BACKGROUND: Left ventricular (LV) remodeling following acute myocardial infarction (MI) is difficult to predict at an individual level although a possible interfering role of vascular function has yet to be considered to date. This study aimed to determine the extent to which this LV remodeling is influenced by the concomitant evolution of vascular function and LV loading conditions, as assessed by phase-contrast Cardiovascular Magnetic Resonance (CMR) of the ascending aorta. METHODS: CMR was performed in 121 patients, 2-4 days after reperfusion of a first ST-segment elevation myocardial infarction and 6 months thereafter. LV remodeling was: (i) assessed by the 6-month increase in end-diastolic volume (EDV) and/or ejection fraction (EF) and (ii) correlated with the indexed aortic stroke volume (mL.m-2), determined by a CMR phase-contrast sequence, along with derived functional vascular parameters (total peripheral vascular resistance (TPVR), total arterial compliance index, effective arterial elastance). RESULTS: At 6 months, most patients were under angiotensin enzyme converting inhibitors (86%) and beta-blockers (84%) and, on average, all functional vascular parameters were improved whereas blood pressure levels were not. An increase in EDV only (EDV+/EF-) was documented in 17% of patients at 6 months, in EF only (EDV-/EF+) in 31%, in both EDV and EF (EDV+/EF+) in 12% and neither EDV nor EF (EDV-/EF-) in 40%. The increase in EF was mainly and independently linked to a concomitant decline in TPVR (6-month change in mmHg.min.m2.L-1, EDV-/EF-: +1 ± 8, EDV+/EF-: +3 ± 9, EDV-/EF+: -7 ± 6, EDV+/EF+: -15 ± 20, p < 0.001) while the absence of any EF improvement was associated with high persisting rates of abnormally high TPVR at 6 months (EDV-/EF-: 31%, EDV+/EF-: 38%, EDV-/EF+: 5%, EDV+/EF+: 13%, p = 0.007). By contrast, the 6-month increase in EDV was mainly dependent on cardiac as opposed to vascular parameters and particularly on the presence of microvascular obstruction at baseline (EDV-/EF-: 37%, EDV+/EF-: 76%, EDV-/EF+: 38%, EDV+/EF+: 73%, p = 0.003). CONCLUSION: LV remodeling following reperfused MI is strongly influenced by the variable decrease in systemic vascular resistance under standard care vasodilating medication. The CMR monitoring of vascular resistance may help to tailor these medications for improving vascular resistance and consequently, LV ejection fraction. TRIAL REGISTRATION: NCT01109225 on ClinicalTrials.gov site (April, 2010).


Assuntos
Aorta/diagnóstico por imagem , Hemodinâmica , Imagem Cinética por Ressonância Magnética , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Função Ventricular Esquerda , Remodelação Ventricular , Antagonistas Adrenérgicos beta/uso terapêutico , Idoso , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Aorta/efeitos dos fármacos , Aorta/fisiopatologia , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Recuperação de Função Fisiológica , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Volume Sistólico , Fatores de Tempo , Resultado do Tratamento , Resistência Vascular , Vasodilatação , Vasodilatadores/uso terapêutico , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos
4.
Radiology ; 273(3): 801-12, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25102294

RESUMO

PURPOSE: To evaluate if measurement of split renal function ( SRF split renal function ) with dynamic contrast material-enhanced ( DCE dynamic contrast enhanced ) magnetic resonance (MR) urography is equivalent to that with renal scintigraphy ( RS renal scintigraphy ) in patients suspected of having chronic urinary obstruction. MATERIALS AND METHODS: The study protocol was approved by the institutional ethics committee of the coordinating center on behalf of all participating centers. Informed consent was obtained from all adult patients or both parents of children. This prospective, comparative study included 369 pediatric and adult patients from 14 university hospitals who were suspected of having chronic or intermittent urinary obstruction, and data from 295 patients with complete data were used for analysis. SRF split renal function was measured by using the area under the curve and the Patlak-Rutland methods, including successive review by a senior and an expert reviewer and measurement of intra- and interobserver agreement for each technique. An equivalence test for mean SRF split renal function was conducted with an α of 5%. RESULTS: Reproducibility was substantial to almost perfect for both methods. Equivalence of DCE dynamic contrast enhanced MR urography and RS renal scintigraphy for measurement of SRF split renal function was shown in patients with moderately dilated kidneys (P < .001 with the Patlak-Rutland method). However, in severely dilated kidneys, the mean SRF split renal function measurement was underestimated by 4% when DCE dynamic contrast enhanced MR urography was used compared with that when RS renal scintigraphy was used. Age and type of MR imaging device had no significant effect. CONCLUSION: For moderately dilated kidneys, equivalence of DCE dynamic contrast enhanced MR urography to RS renal scintigraphy was shown, with a standard deviation of approximately 12% between the techniques, making substitution of DCE dynamic contrast enhanced MR urography for RS renal scintigraphy acceptable. For severely dilated kidneys, a mean underestimation of SRF split renal function of 4% should be expected with DCE dynamic contrast enhanced MR urography, making substitution questionable.


Assuntos
Hidronefrose/diagnóstico , Imageamento por Ressonância Magnética/métodos , Obstrução Uretral/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Doença Crônica , Meios de Contraste , Feminino , Hospitais Universitários , Humanos , Hidronefrose/etiologia , Imageamento Tridimensional , Lactente , Recém-Nascido , Sintomas do Trato Urinário Inferior/diagnóstico , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Obstrução Uretral/etiologia
5.
J Vasc Access ; : 11297298241254675, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801000

RESUMO

INTRODUCTION: Ultrasound-guided placement of peripheral venous catheters requires appropriate equipment. Among the devices used, peripheral venous catheters have different structure and properties. This study aimed to define the impact of these different factors on the echogenicity of peripheral venous catheters. METHOD: An open comparative study was conducted from September 2022 to May 2023. Thirteen devices were introduced in a standardized manner along the longitudinal and transverse axes with the help of guides into a phantom at different angles. Two criteria defined the echogenicity of these devices: the surface occupied by the device in the image (composite criterion: length and diameter of the device and angle of insertion) and its brightness (average of the pixel intensity of gray). Sixty-five ultrasound images were recorded and postprocessed twice (blinded to the previous measurement) by an expert operator, for reproducibility purposes. RESULTS: The intra-observer reproducibility of all measurements was excellent, with an intra-class coefficient of >0.90 over the entire dataset. On the longitudinal axis, echogenicity was significantly influenced by insertion angle (p = 0.009), device length (p = 0.006), and the interaction of cannula component and insertion angle (p = 0.007). On the transverse axis, no factors significantly influenced the device's echogenicity. DISCUSSION: The echogenicity of a device is an essential component of successful ultrasound-guided peripheral venous catheter placement. Optimizing catheter intrinsic factors such as components of the cannula and length, and extrinsic factor like the insertion angle should be considered in their design and use to reduce puncture failure rates.

6.
Neurology ; 102(12): e209427, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38815232

RESUMO

BACKGROUND AND OBJECTIVES: The typical infarct volume trajectories in stroke patients, categorized as slow or fast progressors, remain largely unknown. This study aimed to reveal the characteristic spatiotemporal evolutions of infarct volumes caused by large vessel occlusion (LVO) and show that such growth charts help anticipate clinical outcomes. METHODS: We conducted a secondary analysis from prospectively collected databases (FRAME, 2017-2019; ETIS, 2015-2022). We selected acute MRI data from anterior LVO stroke patients with witnessed onset, which were divided into training and independent validation datasets. In the training dataset, using Gaussian mixture analysis, we classified the patients into 3 growth groups based on their rate of infarct growth (diffusion volume/time-to-imaging). Subsequently, we extrapolated pseudo-longitudinal models of infarct growth for each group and generated sequential frequency maps to highlight the spatial distribution of infarct growth. We used these charts to attribute a growth group to the independent patients from the validation dataset. We compared their 3-month modified Rankin scale (mRS) with the predicted values based on a multivariable regression model from the training dataset that used growth group as an independent variable. RESULTS: We included 804 patients (median age 73.0 years [interquartile range 61.2-82.0 years]; 409 men). The training dataset revealed nonsupervised clustering into 11% (74/703) slow, 62% (437/703) intermediate, and 27% (192/703) fast progressors. Infarct volume evolutions were best fitted with a linear (r = 0.809; p < 0.001), cubic (r = 0.471; p < 0.001), and power (r = 0.63; p < 0.001) function for the slow, intermediate, and fast progressors, respectively. Notably, the deep nuclei and insular cortex were rapidly affected in the intermediate and fast groups with further cortical involvement in the fast group. The variable growth group significantly predicted the 3-month mRS (multivariate odds ratio 0.51; 95% CI 0.37-0.72, p < 0.0001) in the training dataset, yielding a mean area under the receiver operating characteristic curve of 0.78 (95% CI 0.66-0.88) in the independent validation dataset. DISCUSSION: We revealed spatiotemporal archetype dynamic evolutions following LVO stroke according to 3 growth phenotypes called slow, intermediate, and fast progressors, providing insight into anticipating clinical outcome. We expect this could help in designing neuroprotective trials aiming at modulating infarct growth before EVT.


Assuntos
AVC Isquêmico , Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Idoso , AVC Isquêmico/diagnóstico por imagem , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Progressão da Doença
7.
Eur J Heart Fail ; 25(10): 1742-1752, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37530453

RESUMO

AIMS: Whether aldosterone levels after myocardial infarction (MI) are associated with mid- and long-term left ventricular (LV) remodelling in the era of systematic use of renin-angiotensin system inhibitors is uncertain. We prospectively investigated the relationship between aldosterone levels and mid- and long-term LV remodelling in patients with acute MI. METHODS AND RESULTS: Plasma aldosterone was measured in 119 patients successfully treated by primary percutaneous coronary angioplasty for a first acute ST-elevation MI (STEMI) 2-4 days after the acute event. LV volumes were assessed by cardiac magnetic resonance (CMR) and transthoracic echocardiography (TTE) in the same timeframe and 6 months later. LV assessment was repeated by TTE 3-9 years after MI (n = 80). The median aldosterone level at baseline was 23.1 [16.8; 33.1] pg/ml. In the multivariable model, higher post-MI aldosterone concentration was significantly associated with more pronounced increase in LV end-diastolic volume index (TTE: ß ± standard error [SE]: 0.113 ± 0.046, p = 0.015; CMR: ß ± SE: 0.098 ± 0.040, p = 0.015) and LV end-systolic volume index (TTE: ß ± SE: 0.083 ± 0.030, p = 0.008; CMR: ß ± SE: 0.064 ± 0.032, p = 0.048) at 6-month follow-up, regardless of the method of assessment. This result was consistent also in patients with a LV ejection fraction (LVEF) >40%. The association between baseline plasma aldosterone and adverse LV remodelling did not persist at the 3-9-year follow-up evaluation. CONCLUSION: Aldosterone concentration in the acute phase was associated with adverse LV remodelling in the medium term, even in the subgroup of patients with LVEF >40%, suggesting a potential role of the mineralocorticoid system in post-MI adverse remodelling. Plasma aldosterone was no longer associated with LV remodelling in the long term (NCT01109225).


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Aldosterona , Insuficiência Cardíaca/complicações , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Volume Sistólico , Função Ventricular Esquerda , Remodelação Ventricular
8.
Magn Reson Med ; 67(6): 1740-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22135141

RESUMO

Reproducibility of the manual assessment of right ventricle volumes by short-axis cine-MRI remains low and is often attributed to the difficulty in separating the right atrium from the ventricle. This study was designed to evaluate the regional interobserver variability of the right ventricle volume assessment to identify segmentation zones with the highest interobserver variability. Short-axis views of 90 right ventricles (30 hypertrophic, 30 dilated, and 30 normal) were acquired with 2D steady-state free precession sequences at 1.5 T and were manually segmented by two observers. The two segmentations were compared and the variations were quantified with a variation score based on the Hausdorff distance between the two segmentations and the interobserver 95% limits of concordance of the global volumes. The right ventricles were semiautomatically split into four subregions: apex, mid-ventricle, tricuspid zone, and infundibulum. These four subregions represented 11%, 34%, 36%, and 19% of the volume but, respectively, yielded variation scores of 8%, 16%, 42%, and 34%. The infundibulum yielded the highest interobserver regional variability although its variation score remained comparable to the tricuspid zone due to its lower volume. These results emphasize the importance of standardizing the segmentation of the infundibulum and the tricuspid zone to improve reproducibility.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imagem Cinética por Ressonância Magnética/métodos , Reconhecimento Automatizado de Padrão/métodos , Disfunção Ventricular Esquerda/patologia , Adulto , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Tamanho do Órgão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Eur Radiol ; 22(2): 295-301, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21927791

RESUMO

OBJECTIVES: To evaluate the impact of Adaptive Iterative Dose Reduction (AIDR) on image quality and radiation dose in phantom and patient studies. METHODS: A phantom was examined in volumetric mode on a 320-detector CT at different tube currents from 25 to 550 mAs. CT images were reconstructed with AIDR and with Filtered Back Projection (FBP) reconstruction algorithm. Image noise, Contrast-to-Noise Ratio (CNR), Signal-to-Noise Ratio (SNR) and spatial resolution were compared between FBP and AIDR images. AIDR was then tested on 15 CT examinations of the lumbar spine in a prospective study. Again, FBP and AIDR images were compared. Image noise and SNR were analysed using a Wilcoxon signed-rank test. RESULTS: In the phantom, spatial resolution assessment showed no significant difference between FBP and AIDR reconstructions. Image noise was lower with AIDR than with FBP images with a mean reduction of 40%. CNR and SNR were also improved with AIDR. In patients, quantitative and subjective evaluation showed that image noise was significantly lower with AIDR than with FBP. SNR was also greater with AIDR than with FBP. CONCLUSION: Compared to traditional FBP reconstruction techniques, AIDR significantly improves image quality and has the potential to decrease radiation dose. KEY POINTS: This study showed that Adaptive Iterative Dose Reduction (AIDR) reduces image noise. In a phantom image noise was reduced without altering spatial resolution. In patients AIDR reduced the image noise in lumbar spine CT. AIDR can potentially reduce the dose for lumbar spine CT by 52%.


Assuntos
Radiometria/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Algoritmos , Meios de Contraste/farmacologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Vértebras Lombares/patologia , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Projetos Piloto , Estudos Prospectivos , Razão Sinal-Ruído
10.
Diagnostics (Basel) ; 11(11)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34829385

RESUMO

Pretreatment ischemic location may be an important determinant for functional outcome prediction in acute ischemic stroke. In total, 143 anterior circulation ischemic stroke patients in the THRACE study were included. Ischemic lesions were semi-automatically segmented on pretreatment diffusion-weighted imaging and registered on brain atlases. The percentage of ischemic tissue in each atlas-segmented region was calculated. Statistical models with logistic regression and support vector machine were built to analyze the predictors of functional outcome. The investigated parameters included: age, baseline National Institutes of Health Stroke Scale score, and lesional volume (three-parameter model), together with the ischemic percentage in each atlas-segmented region (four-parameter model). The support vector machine with radial basis functions outperformed logistic regression in prediction accuracy. The support vector machine three-parameter model demonstrated an area under the curve of 0.77, while the four-parameter model achieved a higher area under the curve (0.82). Regions with marked impacts on outcome prediction were the uncinate fasciculus, postcentral gyrus, putamen, middle occipital gyrus, supramarginal gyrus, and posterior corona radiata in the left hemisphere; and the uncinate fasciculus, paracentral lobule, temporal pole, hippocampus, inferior occipital gyrus, middle temporal gyrus, pallidum, and anterior limb of the internal capsule in the right hemisphere. In conclusion, pretreatment ischemic location provided significant prognostic information for functional outcome in ischemic stroke.

11.
Front Cardiovasc Med ; 8: 771022, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34805324

RESUMO

Introduction: This study aims to assess the changes in cardiovascular remodeling attributable to bodyweight gain in a middle-aged abdominal obesity cohort. A remodeling worsening might explain the increase in cardiovascular risk associated with a dynamic of weight gain. Methods: Seventy-five middle-aged subjects (56 ± 5 years, 38 women) with abdominal obesity and no known cardiovascular disease underwent MRI-based examinations at baseline and at a 6.1 ± 1.2-year follow-up to monitor cardiovascular remodeling and hemodynamic variables, most notably the effective arterial elastance (Ea). Ea is a proxy of the arterial load that must be overcome during left ventricular (LV) ejection, with increased EA resulting in concentric LV remodeling. Results: Sixteen obese subjects had significant weight gain (>7%) during follow-up (WG+), whereas the 59 other individuals did not (WG-). WG+ and WG- exhibited significant differences in the baseline to follow-up evolutions of several hemodynamic parameters, notably diastolic and mean blood pressures (for mean blood pressure, WG+: +9.3 ± 10.9 mmHg vs. WG-: +1.7 ± 11.8 mmHg, p = 0.022), heart rate (WG+: +0.6 ± 9.4 min-1 vs. -8.9 ± 11.5 min-1, p = 0.003), LV concentric remodeling index (WG: +0.08 ± 0.16 g.mL-1 vs. WG-: -0.02 ± 0.13 g.mL-1, p = 0.018) and Ea (WG+: +0.20 ± 0.28 mL mmHg-1 vs. WG-: +0.01 ± 0.30 mL mmHg-1, p = 0.021). The evolution of the LV concentric remodeling index and Ea were also strongly correlated in the overall obese population (p < 0.001, R2 = 0.31). Conclusions: A weight gain dynamic is accompanied by increases in arterial load and load-related concentric LV remodeling in an isolated abdominal obesity cohort. This remodeling could have a significant impact on cardiovascular risk.

12.
Front Cardiovasc Med ; 8: 803567, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35004914

RESUMO

Introduction: This cardiovascular magnetic resonance (CMR) study aims to determine whether changes in systemic vascular resistance (SVR), obtained from CMR flow sequences, might explain the significant long-term changes in left ventricular (LV) ejection fraction (EF) observed in subjects with no cardiac disease history. Methods: Cohort subjects without any known cardiac disease but with high rates of hypertension and obesity, underwent CMR with phase-contrast sequences both at baseline and at a median follow-up of 5.2 years. Longitudinal changes in EF were analyzed for any concomitant changes in blood pressure and vascular function, notably the indexed SVR given by the formula: mean brachial blood pressure / cardiac output x body surface area. Results: A total of 118 subjects (53 ± 12 years, 52% women) were included, 26% had hypertension, and 52% were obese. Eighteen (15%) had significant EF variations between baseline and follow-up (7 increased EF and 11 decreased EF). Longitudinal changes in EF were inversely related to concomitant changes in mean and diastolic blood pressures (p = 0.030 and p = 0.027, respectively) and much more significantly to SVR (p < 0.001). On average, these SVR changes were -8.08 ± 9.21 and +8.14 ± 8.28 mmHg.min.m2.L-1, respectively, in subjects with significant increases and decreases in EF, and 3.32 ± 7.53 mmHg.min.m2.L-1 in subjects with a stable EF (overall p < 0.001). Conclusions: Significant EF variations are not uncommon during the long-term CMR follow-up of populations with no evident health issues except for uncomplicated hypertension and obesity. However, most of these variations are linked to SVR changes and may therefore be unrelated to any intrinsic change in LV contractility. This underscores the benefits of specifically assessing LV afterload when EF is monitored in populations at risk of vascular dysfunction. Clinical Trial Registration: ClinicalTrials.gov, identifier: NCT01716819 and NCT02430805.

13.
PLoS One ; 15(5): e0232572, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392260

RESUMO

OBJECTIVES: In a previous analysis of a post-myocardial infarction (MI) cohort, abnormally high systemic vascular resistances (SVR) were shown to be frequently revealed by MRI during the healing period, independently of MI severity, giving evidence of vascular dysfunction and limiting further recovery of cardiac function. The present ancillary and exploratory analysis of the same cohort was aimed at characterizing those patients suffering from high SVR remotely from MI with a large a panel of cardiovascular MRI parameters and blood biomarkers. METHODS: MRI and blood sampling were performed 2-4 days after a reperfused MI and 6 months thereafter in 121 patients. SVR were monitored with a phase-contrast MRI sequence and patients with abnormally high SVR at 6-months were characterized through MRI parameters and blood biomarkers, including Galectin-3, an indicator of cardiovascular inflammation and fibrosis after MI. SVR were normal at 6-months in 90 patients (SVR-) and abnormally high in 31 among whom 21 already had high SVR at the acute phase (SVR++) while 10 did not (SVR+). RESULTS: When compared with SVR-, both SVR+ and SVR++ exhibited lower recovery in cardiac function from baseline to 6-months, while baseline levels of Galectin-3 were significantly different in both SVR+ (median: 14.4 (interquartile range: 12.3-16.7) ng.mL-1) and SVR++ (13.0 (11.7-19.4) ng.mL-1) compared to SVR- (11.7 (9.8-13.5) ng.mL-1, both p < 0.05). Plasma Galectin-3 was an independent baseline predictor of high SVR at 6-months (p = 0.002), together with the baseline levels of SVR and left ventricular end-diastolic volume, whereas indices of MI severity and left ventricular function were not. In conclusion, plasma Galectin-3 predicts a deleterious vascular dysfunction affecting post-MI patients, an observation that could lead to consider new therapeutic targets if confirmed through dedicated prospective studies.


Assuntos
Galectina 3/sangue , Infarto do Miocárdio/complicações , Doenças Vasculares/etiologia , Idoso , Biomarcadores/sangue , Proteínas Sanguíneas , Feminino , Galectinas , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Fatores de Risco , Doenças Vasculares/sangue , Doenças Vasculares/diagnóstico por imagem , Doenças Vasculares/fisiopatologia , Resistência Vascular/fisiologia
14.
J Alzheimers Dis ; 74(1): 227-235, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32039844

RESUMO

BACKGROUND: Hippocampal atrophy is associated with cognitive decline. Determining the clinical features associated with hippocampal volume (HV)/atrophy may help in tailoring preventive strategies. OBJECTIVE: This study was aimed to investigate the association between HV (at visit 2) and vascular status (both at visit 1 and visit 2) in a cohort of individuals aged 60+ with hypertension and without overt cognitive impairment at visit 1 (visit 1 and visit 2 were separated by approximately 8 years). METHODS: Hippocampal volume was estimated in brain MRIs as HV both clinically with the Scheltens' Medial Temporal Atrophy score, and automatically with the Free Surfer Software application. A detailed medical history, somatometric measurements, cognitive tests, leukoaraiosis severity (Fazekas score), vascular parameters including pulse wave velocity, central blood pressure, and carotid artery plaques, as well as several biochemical parameters were also measured. RESULTS: 113 hypertensive patients, 47% male, aged 75.1±5.6 years, participated in both visit 1 and visit 2 of the ADELAHYDE study. Age (ß= -0.30) and hypertension duration (ß= -0.20) at visit 1 were independently associated with smaller HV at visit 2 (p < 0.05 for all). In addition to these variables, low body mass index (ß= 0.18), high MRI Fazekas score (ß= -0.20), and low Gröber-Buschke total recall (ß= 0.27) were associated with smaller HV at visit 2 (p < 0.05 for all). CONCLUSION: In a cohort of older individuals without cognitive impairment at baseline, we described several factors associated with lower HV, of which hypertension duration can potentially be modified.


Assuntos
Hipocampo/diagnóstico por imagem , Hipertensão/diagnóstico por imagem , Microvasos/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Atrofia , Pressão Sanguínea , Índice de Massa Corporal , Disfunção Cognitiva/patologia , Estudos de Coortes , Feminino , Genótipo , Humanos , Hipertensão/genética , Hipertensão/psicologia , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Rememoração Mental , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos , Substância Branca/diagnóstico por imagem
15.
Mol Imaging Biol ; 21(3): 549-557, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30073569

RESUMO

PURPOSE: 6-[18F]fluoro-L-DOPA ([18F]FDOPA), a positron emission tomography (PET) amino-acid tracer of brain decarboxylase activity, is used to assess the brain dopaminergic system. Using a voxel-based semi-quantitative analysis, this study aimed to determine whether a current brain uptake index of [18F]FDOPA, expressed relative to the occipital background level, varies according to age and gender. PROCEDURES: One hundred and seventy-seven subjects were retrospectively included. A whole-brain statistical parametric mapping analysis of the [18F]FDOPA uptake index in parametric PET images was performed at a voxel threshold of p < 0.05 (corrected) and p < 0.005 (uncorrected, k cluster > 125). RESULTS: Striatal uptake indices were influenced by age, negatively for the caudate nucleus and positively for the putamen, as well as by gender, with a lower left putaminal uptake index in women. Extra-striatal uptake indices were influenced by age, negatively for the frontal cortex and brainstem and positively for the occipital cortex and cerebellum, as well as by gender (diffuse increase in women). CONCLUSIONS: The uptake index of [18F]FDOPA exhibited significant physiological variations according to age and gender and should therefore be considered for PET interpretation.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Di-Hidroxifenilalanina/análogos & derivados , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Corpo Estriado/metabolismo , Di-Hidroxifenilalanina/química , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Distribuição Tecidual , Adulto Jovem
16.
Lancet Neurol ; 17(1): 47-53, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29263006

RESUMO

BACKGROUND: General anaesthesia (GA) during endovascular thrombectomy has been associated with worse patient outcomes in observational studies compared with patients treated without GA. We assessed functional outcome in ischaemic stroke patients with large vessel anterior circulation occlusion undergoing endovascular thrombectomy under GA, versus thrombectomy not under GA (with or without sedation) versus standard care (ie, no thrombectomy), stratified by the use of GA versus standard care. METHODS: For this meta-analysis, patient-level data were pooled from all patients included in randomised trials in PuMed published between Jan 1, 2010, and May 31, 2017, that compared endovascular thrombectomy predominantly done with stent retrievers with standard care in anterior circulation ischaemic stroke patients (HERMES Collaboration). The primary outcome was functional outcome assessed by ordinal analysis of the modified Rankin scale (mRS) at 90 days in the GA and non-GA subgroups of patients treated with endovascular therapy versus those patients treated with standard care, adjusted for baseline prognostic variables. To account for between-trial variance we used mixed-effects modelling with a random effect for trials incorporated in all models. Bias was assessed using the Cochrane method. The meta-analysis was prospectively designed, but not registered. FINDINGS: Seven trials were identified by our search; of 1764 patients included in these trials, 871 were allocated to endovascular thrombectomy and 893 were assigned standard care. After exclusion of 74 patients (72 did not undergo the procedure and two had missing data on anaesthetic strategy), 236 (30%) of 797 patients who had endovascular procedures were treated under GA. At baseline, patients receiving GA were younger and had a shorter delay between stroke onset and randomisation but they had similar pre-treatment clinical severity compared with patients who did not have GA. Endovascular thrombectomy improved functional outcome at 3 months both in patients who had GA (adjusted common odds ratio (cOR) 1·52, 95% CI 1·09-2·11, p=0·014) and in those who did not have GA (adjusted cOR 2·33, 95% CI 1·75-3·10, p<0·0001) versus standard care. However, outcomes were significantly better for patients who did not receive GA versus those who received GA (covariate-adjusted cOR 1·53, 95% CI 1·14-2·04, p=0·0044). The risk of bias and variability between studies was assessed to be low. INTERPRETATION: Worse outcomes after endovascular thrombectomy were associated with GA, after adjustment for baseline prognostic variables. These data support avoidance of GA whenever possible. The procedure did, however, remain effective versus standard care in patients treated under GA, indicating that treatment should not be withheld in those who require anaesthesia for medical reasons. FUNDING: Medtronic.


Assuntos
Anestesia Geral/métodos , Isquemia Encefálica/terapia , Avaliação de Processos e Resultados em Cuidados de Saúde/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Acidente Vascular Cerebral/terapia , Trombectomia/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Forensic Sci Int ; 271: 113-119, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28081518

RESUMO

Age estimation of living individuals aged less than 13, 18 or 21 years, which are some relevant legal ages in most European countries, is currently problematic in the forensic context. Thus, numerous methods are available for legal authorities, although their efficiency can be discussed. For those reasons, we aimed to propose a new method, based on the biometric analysis of hand bones. 451 hand radiographs of French individuals under the age of 21 were retrospectively analyzed. This total sample was divided into three subgroups bounded by the relevant legal ages previously mentioned: 0-13, 13-18 and 18-21 years. On these radiographs, we numerically applied the osteometric board method used in anthropology, by including each metacarpal and proximal phalange of the five hand rays in the smallest rectangle possible. In that we can access their length and width information thanks to a measurement protocol developed precisely for our treatment with the ORS Visual® software. Then, a statistical analysis was performed from these biometric data: a Linear Discriminant Analysis (LDA) evaluated the probability for an individual to belong to one of the age group (0-13, 13-18 or 18-21); and several multivariate regression models were tested for the establishment of age estimation formulas for each of these age groups. The mean Correlation Coefficient between chronological age and both lengths and widths of hand bones is equal to 0.90 for the total sample. Repeatability and reproducibility were assessed. The LDA could more easily predict the belonging to the 0-13 age group. Age can be estimated with a mean standard error which never exceeds 1 year for the 95% confidence interval. Finally, compared to the literature, we can conclude that estimating an age from the biometric information of metacarpals and proximal phalanges is promising.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Ossos da Mão/anatomia & histologia , Ossos da Mão/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Análise Discriminante , Feminino , Antropologia Forense , Humanos , Lactente , Recém-Nascido , Masculino , Análise Multivariada , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
18.
J Hypertens ; 34(5): 967-73, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26909645

RESUMO

OBJECTIVES: Blood pressure (BP) and its changes with antihypertensive therapy are key parameters when monitoring left ventricular (LV) remodeling. This dual cross-sectional and longitudinal MRI study aimed to determine whether this monitoring is enhanced by aortic stroke volume (SV) values provided by a phase-contrast sequence. METHODS: The study involved 334 MRI examinations from 247 study participants who had no significant cardiac disease (18-85 years old, 40% with hypertension) and among whom 48 had a 2-4-year MRI follow-up. Left ventricular hypertrophy and concentric geometry were: respectively assessed according to LV mass indexed to body surface area (g/m) and mass/end-diastolic volume ratio (concentric remodeling index); and correlated with vascular parameters involving BP and the indexed SV (ml/m) determined in the ascending aorta with a phase-contrast sequence. RESULTS: Stroke volume was highly variable, ranging from 22 to 74 ml/m. The best cross-sectional correlates were: mean BP × SV product, reflecting cardiac work, for LV mass (r = 0.21); and mean BP/SV ratio, reflecting arterial load, for concentric geometry (r = 0.29). These two SV-derived parameters led to more than two-fold enhancements in cross-sectional predictions compared with BP parameters alone, whereas their longitudinal changes over time paralleled those of concentric geometry (P = 0.003 for mean BP/SV) and LV mass (P = 0.006 for mean BP × SV), suggesting direct links with cardiac remodeling. CONCLUSION: The determination of aortic SV with a phase-contrast sequence leads to a significant enhancement in the characterization and monitoring of cardiac remodeling.


Assuntos
Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Hipertrofia Ventricular Esquerda/fisiopatologia , Volume Sistólico/fisiologia , Remodelação Ventricular/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Hipertensão/fisiopatologia , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
Clin Res Cardiol ; 105(10): 815-26, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27108156

RESUMO

BACKGROUND: Identification of transmural extent and degree of non-viability after ST-segment elevation myocardial infarction (STEMI) is clinically important. The objective of the present study was to assess the regional mechanics and temporal deformation patterns using speckle tracking echocardiography (STE) in acute and later phases of STEMI to predict myocardial damage in these patients. METHODS AND RESULTS: Ninety-eight patients with first STEMI underwent both echocardiography and cardiac magnetic resonance imaging in acute phase and at 6 months follow-up with 2D STE-derived measurements of peak longitudinal strain (PLS), Pre-STretch index (PST) and post-systolic deformation index (PSI). For each segment, late gadolinium enhancement (LGE) was defined as transmural (LGE >66 %) or non-transmural (<66 %). Global deformation values were significantly correlated with LVEFCMR and infarct size at both visits. A significantly lower value of segmental PLS and higher PSI and PST in necrotic segments were observed comparatively to control, adjacent and remote segments. The best parameters to predict transmural extent in acute phase were PSI with a cutoff value of 8 % (AUC: 0.84) and PLS with a cutoff value of -13 % (AUC: 0.86). PST showed high specificity, but poor sensitivity in predicting transmural extent. More importantly, the addition of PSI and PST to PLS in acute phase was associated with improved prediction of viability at 6 months (integrated discrimination improvement 2.5 % p < 0.01; net reclassification improvement 27 %; p < 0.01). CONCLUSIONS: All systolic deformation values separated transmural from non-transmural scarring. PLS combined with additional information relative to post-systolic deformation appears to be the most informative parameters to predict the transmural extent of MI in the early and late phases of MI. CLINICAL TRIAL REGISTRATION: http://clinicaltrials.gov/show/NCT01109225 ; NCT01109225.


Assuntos
Ecocardiografia , Imagem Cinética por Ressonância Magnética , Contração Miocárdica , Miocárdio/patologia , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Função Ventricular Esquerda , Idoso , Fenômenos Biomecânicos , Meios de Contraste , Feminino , França , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Infarto do Miocárdio com Supradesnível do Segmento ST/patologia , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Estresse Mecânico , Fatores de Tempo , Sobrevivência de Tecidos
20.
Int J Cardiovasc Imaging ; 31(7): 1337-46, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26044525

RESUMO

Microvascular obstruction (MVO) and transmural infarct size are prognostic factors after acute myocardial infarction (AMI). We assessed the value of myocardial deformation patterns using 3D speckle tracking imaging (3DSTI) in detecting myocardial and microvascular damage after AMI. One hundred patients with first ST-segment elevation MI from the REMI Study were prospectively included. Transthoracic echocardiography with 3DSTI and CMR were performed within 72 h after revascularization therapy. Global (3DG) and segmental (3DS) values of LV longitudinal (LS), circumferential and radial area strain were obtained. Late gadolinium enhancement (LGE) and MVO was quantified as transmural (>50%) or non-transmural (<50%). Predictive performance was assessed by area under the receiver operating curve characteristic (AUC). Mean LVEFCMR was 45.8 ± 9.2 % with 22.2 ± 12.7% transmural LGE. MVO was present in 55 patients (MVO transmural extent 11.4 ± 11.8%). In global analysis, all 3DG strain values were correlated with LVEFCMR and infarct size, with the best correlation obtained for 3DGAS (r = -0.678; p < 0.0001). All 3DG strain values, with the exception of LS, were significantly different between patients with and without MVO. In segmental analysis, all 3DS strain values were significantly lower in transmurally infarcted segments than in non-infarcted segments, and all 3DS values except 3DSRS were significantly lower in non-transmural infarcted segments than in non-infarcted segments. The best 3DS strain for detecting non-viable segments with MVO (MVO > 75%) was 3DSAS [AUC 0.867 (0.849-0.884), 78.0% sensitivity and 81.1% specificity for 3DSAS = -16.1%]. Importantly, 3DSRS and 3DSAS were associated with an increase in diagnostic accuracy of both transmural LGE and MVO over 3DSLS (all increase in AUC > 0.04, all p < 0.01). The newly developed 3DSTI, especially 3DSAS, is a sensitive and reproducible tool to predict and quantify the transmural extent of scar. This new early imaging strategy improve the prediction of MVO while enabling to assess the success of reperfusion and the risk of late systolic remodeling in STEMI.


Assuntos
Circulação Coronária , Ecocardiografia Tridimensional , Microcirculação , Infarto do Miocárdio/diagnóstico por imagem , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda , Adulto , Idoso , Área Sob a Curva , Fenômenos Biomecânicos , Feminino , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Revascularização Miocárdica , Variações Dependentes do Observador , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/terapia , Remodelação Ventricular
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA