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1.
Sensors (Basel) ; 23(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36679731

RESUMO

It is well established that most of the plastic pollution found in the oceans is transported via rivers. Unfortunately, the main processes contributing to plastic and debris displacement through riparian systems is still poorly understood. The Marine Litter Drifter project from the Arno River aims at using modern consumer software and hardware technologies to track the movements of real anthropogenic marine debris (AMD) from rivers. The innovative "Marine Litter Trackers" (MLT) were utilized as they are reliable, robust, self-powered and they present almost no maintenance costs. Furthermore, they can be built not only by those trained in the field but also by those with no specific expertise, including high school students, simply by following the instructions. Five dispersion experiments were successfully conducted from April 2021 to December 2021, using different types of trackers in different seasons and weather conditions. The maximum distance tracked was 2845 km for a period of 94 days. The activity at sea was integrated by use of Lagrangian numerical models that also assisted in planning the deployments and the recovery of drifters. The observed tracking data in turn were used for calibration and validation, recursively improving their quality. The dynamics of marine litter (ML) dispersion in the Tyrrhenian Sea is also discussed, along with the potential for open-source approaches including the "citizen science" perspective for both improving big data collection and educating/awareness-raising on AMD issues.


Assuntos
Ciência do Cidadão , Resíduos , Humanos , Resíduos/análise , Monitoramento Ambiental , Poluição Ambiental , Plásticos
2.
Cardiovasc Ultrasound ; 15(1): 3, 2017 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-28100277

RESUMO

BACKGROUND: Stress echocardiography (SE) has an established role in evidence-based guidelines, but recently its breadth and variety of applications have extended well beyond coronary artery disease (CAD). We lack a prospective research study of SE applications, in and beyond CAD, also considering a variety of signs in addition to regional wall motion abnormalities. METHODS: In a prospective, multicenter, international, observational study design, > 100 certified high-volume SE labs (initially from Italy, Brazil, Hungary, and Serbia) will be networked with an organized system of clinical, laboratory and imaging data collection at the time of physical or pharmacological SE, with structured follow-up information. The study is endorsed by the Italian Society of Cardiovascular Echography and organized in 10 subprojects focusing on: contractile reserve for prediction of cardiac resynchronization or medical therapy response; stress B-lines in heart failure; hypertrophic cardiomyopathy; heart failure with preserved ejection fraction; mitral regurgitation after either transcatheter or surgical aortic valve replacement; outdoor SE in extreme physiology; right ventricular contractile reserve in repaired Tetralogy of Fallot; suspected or initial pulmonary arterial hypertension; coronary flow velocity, left ventricular elastance reserve and B-lines in known or suspected CAD; identification of subclinical familial disease in genotype-positive, phenotype- negative healthy relatives of inherited disease (such as hypertrophic cardiomyopathy). RESULTS: We expect to recruit about 10,000 patients over a 5-year period (2016-2020), with sample sizes ranging from 5,000 for coronary flow velocity/ left ventricular elastance/ B-lines in CAD to around 250 for hypertrophic cardiomyopathy or repaired Tetralogy of Fallot. This data-base will allow to investigate technical questions such as feasibility and reproducibility of various SE parameters and to assess their prognostic value in different clinical scenarios. CONCLUSIONS: The study will create the cultural, informatic and scientific infrastructure connecting high-volume, accredited SE labs, sharing common criteria of indication, execution, reporting and image storage of SE to obtain original safety, feasibility, and outcome data in evidence-poor diagnostic fields, also outside the established core application of SE in CAD based on regional wall motion abnormalities. The study will standardize procedures, validate emerging signs, and integrate the new information with established knowledge, helping to build a next-generation SE lab without inner walls.


Assuntos
Cardiomiopatias/diagnóstico , Ecocardiografia sob Estresse/métodos , Ventrículos do Coração/diagnóstico por imagem , Isquemia Miocárdica/diagnóstico , Idoso , Cardiomiopatias/fisiopatologia , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Estudos Prospectivos , Reprodutibilidade dos Testes
3.
Int J Mol Sci ; 16(5): 10121-33, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25950760

RESUMO

A thrombotic occlusion of the vessel fed by ruptured coronary atherosclerotic plaque may result in unstable angina, myocardial infarction or death, whereas embolization from a plaque in carotid arteries may result in transient ischemic attack or stroke. The atherosclerotic plaque prone to such clinical events is termed high-risk or vulnerable plaque, and its identification in humans before it becomes symptomatic has been elusive to date. Ultrasonic tissue characterization of the atherosclerotic plaque is possible with different techniques--such as vascular, transesophageal, and intravascular ultrasound--on a variety of arterial segments, including carotid, aorta, and coronary districts. The image analysis can be based on visual, video-densitometric or radiofrequency methods and identifies three distinct textural patterns: hypo-echoic (corresponding to lipid- and hemorrhage-rich plaque), iso- or moderately hyper-echoic (fibrotic or fibro-fatty plaque), and markedly hyperechoic with shadowing (calcific plaque). Hypoechoic or dishomogeneous plaques, with spotty microcalcification and large plaque burden, with plaque neovascularization and surface irregularities by contrast-enhanced ultrasound, are more prone to clinical complications than hyperechoic, extensively calcified, homogeneous plaques with limited plaque burden, smooth luminal plaque surface and absence of neovascularization. Plaque ultrasound morphology is important, along with plaque geometry, in determining the atherosclerotic prognostic burden in the individual patient. New quantitative methods beyond backscatter (to include speed of sound, attenuation, strain, temperature, and high order statistics) are under development to evaluate vascular tissues. Although not yet ready for widespread clinical use, tissue characterization is listed by the American Society of Echocardiography roadmap to 2020 as one of the most promising fields of application in cardiovascular ultrasound imaging, offering unique opportunities for the early detection and treatment of atherosclerotic disease.


Assuntos
Ecocardiografia/métodos , Endossonografia/métodos , Placa Aterosclerótica/diagnóstico por imagem , Ultrassonografia de Intervenção/métodos , Animais , Humanos
4.
J Urol ; 185(6): 2126-31, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21496853

RESUMO

PURPOSE: We evaluated the ability of the phosphodiesterase-5 inhibitor vardenafil to increase prostate microcirculation during power Doppler ultrasound. We also evaluated the results of contrast and vardenafil enhanced targeted biopsies compared to those of standard 12-core random biopsies to detect cancer. MATERIALS AND METHODS: Between May 2008 and January 2010, 150 consecutive patients with prostate specific antigen more than 4 ng/ml at first diagnosis with negative digital rectal examination and transrectal ultrasound, and no clinical history of prostatitis underwent contrast enhanced power Doppler ultrasound (bolus injection of 2.4 ml SonoVue® contrast agent), followed by vardenafil enhanced power Doppler ultrasound (1 hour after oral administration of vardenafil 20 mg). All patients underwent standard 12-core transrectal ultrasound guided random prostate biopsy plus 1 further sampling from each suspected hypervascular lesion detected by contrast and vardenafil enhanced power Doppler ultrasound. RESULTS: Prostate cancer was detected in 44 patients (29.3%). Contrast and vardenafil enhanced power Doppler ultrasound detected suspicious, contrast enhanced and vardenafil enhanced areas in 112 (74.6%) and 110 patients (73.3%), and was diagnostic for cancer in 32 (28.5%) and 42 (38%), respectively. Analysis of standard technique, and contrast and vardenafil enhanced power Doppler ultrasound findings by biopsy core showed significantly higher detection using vardenafil vs contrast enhanced power Doppler ultrasound and standard technique (41.2% vs 22.7% and 8.1%, p <0.005 and <0.001, respectively). The detection rate of standard plus contrast or vardenafil enhanced power Doppler ultrasound was 10% and 11.7% (p not significant). CONCLUSIONS: Vardenafil enhanced power Doppler ultrasound enables excellent visualization of the microvasculature associated with cancer and can improve the detection rate compared to contrast enhanced power Doppler ultrasound and the random technique.


Assuntos
Meios de Contraste , Imidazóis , Inibidores da Fosfodiesterase 5 , Piperazinas , Próstata/irrigação sanguínea , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Ultrassonografia Doppler , Idoso , Biópsia/métodos , Humanos , Masculino , Estudos Prospectivos , Neoplasias da Próstata/irrigação sanguínea , Sulfonas , Triazinas , Dicloridrato de Vardenafila
5.
J Pineal Res ; 51(1): 136-44, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21470301

RESUMO

The present study assessed the in vivo rat pial microvascular responses induced by melatonin during brain hypoperfusion and reperfusion (RE) injury. Pial microcirculation of male Wistar rats was visualized by fluorescence microscopy through a closed cranial window. Hypoperfusion was induced by bilateral common carotid artery occlusion (BCCAO, 30 min); thereafter, pial microcirculation was observed for 60 min. Arteriolar diameter, permeability increase, leukocyte adhesion to venular walls, perfused capillary length (PCL), and capillary red blood cell velocity (V(RBC) ) were investigated by computerized methods. Melatonin (0.5, 1, 2 mg/kg b.w.) was intravenously administered 10 min before BCCAO and at the beginning of RE. Pial arterioles were classified in five orders according to diameter, length, and branchings. In control group, BCCAO caused decrease in order 2 arteriole diameter (by 17.5 ± 3.0% of baseline) that was reduced by 11.8 ± 1.2% of baseline at the end of RE, accompanied by marked leakage and leukocyte adhesion. PCL and capillary V(RBC) decreased. At the end of BCCAO, melatonin highest dosage caused order 2 arteriole diameter reduction by 4.6 ± 2.0% of baseline. At RE, melatonin at the lower dosages caused different arteriolar responses. The highest dosage caused dilation in order 2 arteriole by 8.0 ± 1.5% of baseline, preventing leakage and leukocyte adhesion, while PCL and V(RBC) increased. Luzindole (4 mg/kg b.w.) prior to melatonin caused order 2 arteriole constriction by 12.0 ± 1.5% of baseline at RE, while leakage, leukocyte adhesion, PCL and V(RBC) were not affected. Prazosin (1 mg/kg b.w.) prior to melatonin did not significantly change melatonin's effects. In conclusion, melatonin caused different responses during hypoperfusion and RE, modulating pial arteriolar tone likely by MT1 and MT2 melatonin receptors while preventing blood-brain barrier changes through its free radical scavenging action.


Assuntos
Estenose das Carótidas/tratamento farmacológico , Melatonina/farmacologia , Pia-Máter/irrigação sanguínea , Análise de Variância , Animais , Permeabilidade Capilar/efeitos dos fármacos , Artéria Carótida Primitiva/cirurgia , Estenose das Carótidas/patologia , Veias Cerebrais/anatomia & histologia , Veias Cerebrais/efeitos dos fármacos , Veias Cerebrais/patologia , Masculino , Microvasos/efeitos dos fármacos , Microvasos/metabolismo , Prazosina/farmacologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Receptores de Melatonina/antagonistas & inibidores , Receptores de Melatonina/metabolismo , Reperfusão , Estatísticas não Paramétricas , Triptaminas/farmacologia
6.
Mar Pollut Bull ; 169: 112542, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34052588

RESUMO

Unmanned aerial systems (UAS, aka drones) are being used to map macro-litter on the environment. Sixteen qualified researchers (operators), with different expertise and nationalities, were invited to identify, mark and categorize the litter items (manual image screening, MS) on three UAS images collected at two beaches. The coefficient of concordance (W) among operators varied between 0.5 and 0.7, depending on the litter parameter (type, material and colour) considered. Highest agreement was obtained for the type of items marked on the highest resolution image, among experts in litter surveys (W = 0.86), and within territorial subgroups (W = 0.85). Therefore, for a detailed categorization of litter on the environment, the MS should be performed by experienced and local operators, familiar with the most common type of litter present in the target area. This work provides insights for future operational improvements and optimizations of UAS-based images analysis to survey environmental pollution.


Assuntos
Praias , Resíduos , Monitoramento Ambiental , Poluição Ambiental/análise , Processamento de Imagem Assistida por Computador , Plásticos , Resíduos/análise
7.
Int J Cardiovasc Imaging ; 37(3): 953-964, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33057991

RESUMO

An enlarged left atrial volume index (LAVI) at rest mirrors increased LA pressure and/or impairment of LA function. A cardiovascular stress may acutely modify left atrial volume (LAV) within minutes. Aim of this study was to assess the feasibility and functional correlates of LAV-stress echocardiography (SE) Out of 514 subjects referred to 10 quality-controlled labs, LAV-SE was completed in 490 (359 male, age 67 ± 12 years) with suspected or known chronic coronary syndromes (n = 462) or asymptomatic controls (n = 28). The utilized stress was exercise in 177, vasodilator in 167, dobutamine in 146. LAV was measured with the biplane disk summation method. SE was performed with the ABCDE protocol. The intra-observer and inter-observer LAV variability were 5% and 8%, respectively. ∆-LAVI changes (stress-rest) were negatively correlated with resting LAVI (r = - 0.271, p < 0.001) and heart rate reserve (r = -.239, p < 0.001). LAV-dilators were defined as those with stress-rest increase ≥ 6.8 ml/m2, a cutoff derived from a calculated reference change value above the biological, analytical and observer variability of LAVI. LAV dilation occurred in 56 patients (11%), more frequently with exercise (16%) and dipyridamole (13%) compared to dobutamine (4%, p < 0.01). At multivariable logistic regression analysis, B-lines ≥ 2 (OR: 2.586, 95% CI = 1.1293-5.169, p = 0.007) and abnormal contractile reserve (OR: 2.207, 95% CI = 1.111-4.386, p = 0.024) were associated with LAV dilation. In conclusion, LAV-SE is feasible with high success rate and low variability in patients with chronic coronary syndromes. LAV dilation is more likely with reduced left ventricular contractile reserve and pulmonary congestion.


Assuntos
Função do Átrio Esquerdo , Pressão Atrial , Doença da Artéria Coronariana/diagnóstico por imagem , Ecocardiografia Doppler de Pulso , Ecocardiografia sob Estresse , Átrios do Coração/diagnóstico por imagem , Agonistas de Receptores Adrenérgicos beta 1/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Argentina , Brasil , Doença Crônica , Doença da Artéria Coronariana/fisiopatologia , Europa (Continente) , Exercício Físico , Estudos de Viabilidade , Feminino , Átrios do Coração/fisiopatologia , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Síndrome , Vasodilatadores/administração & dosagem
8.
Eur J Prev Cardiol ; 27(12): 1294-1306, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31266355

RESUMO

In the last few years, multiple echocardiographic nomograms have been published. However, normal values calculated in the general population are not applicable to athletes, whose hearts may be enlarged and hypercontractile. Accordingly, athletes require specific nomograms. Our aim is to provide a critical review of echocardiographic nomograms on two-dimensional (2D) measures for athletes. We performed a systematic search in the National Library of Medicine for Medical Subject Headings and free text terms including echocardiography, athletes, normal values and nomograms. The search was refined by adding the keywords heart, sport, elite, master, children and young. Twenty-eight studies were selected for the final analysis. Our research revealed that currently available ranges of normality for athletes reported by different authors are quite consistent, with limited exceptions (e.g. atria, aorta). Numerical and methodological limitations, however, emerged. Numerical limitations included a limited sample size (e.g. < 450 subjects) of the population assessed and the paucity of data in women, non-Caucasian athletes, and junior and master athletes. Some data on M-mode measurements are available, while those for some specific structures (e.g. left atrial (LA) area and volumes, right ventricular diameters and aorta) are limited or rare (e.g. LA area). There was heterogeneity in data normalization (by gender, sport type and ethnicity) and their expression was limited to mean values (Z-scores have rarely been employed), while variability analysis was often lacking or incomplete. We conclude that comprehensive nomograms using an appropriate sample size, evaluating a complete dataset of 2D (and three-dimensional) measures and built using a rigorous statistical approach are warranted.


Assuntos
Atletas , Cardiomegalia Induzida por Exercícios/fisiologia , Ecocardiografia/métodos , Átrios do Coração/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Função Ventricular Esquerda/fisiologia , Seguimentos , Humanos
9.
J Am Coll Cardiol ; 74(18): 2278-2291, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31672185

RESUMO

BACKGROUND: The assessment of coronary flow velocity reserve (CFVR) in left anterior descending coronary artery (LAD) expands the risk stratification potential of stress echocardiography (SE) based on stress-induced regional wall motion abnormalities (RWMA). OBJECTIVES: The purpose of this study was to assess the feasibility and functional correlates of CFVR. METHODS: This prospective, observational, multicenter study initially screened 3,410 patients (2,061 [60%] male; age 63 ± 11 years; ejection fraction 61 ± 9%) with known or suspected coronary artery disease and/or heart failure. All patients underwent SE (exercise, n = 1,288; vasodilator, n = 1,860; dobutamine, n = 262) based on new or worsening RWMA in 20 accredited laboratories of 8 countries. CFVR was calculated as the stress/rest ratio of diastolic peak flow velocity pulsed-Doppler assessment of LAD flow. A subset of 1,867 patients was followed up. RESULTS: The success rate for CFVR on LAD was 3,002 of 3,410 (feasibility = 88%). Reduced (≤2.0) CFVR was found in 896 of 3,002 (30%) patients. At multivariable logistic regression analysis, inducible RWMA (odds ratio [OR]: 6.5; 95% confidence interval [CI]: 4.9 to 8.5; p < 0.01), abnormal left ventricular contractile reserve (OR: 3.4; 95% CI: 2.7 to 4.2; p < 0.01), and B-lines (OR: 1.5; 95% CI: 1.1 to 1.9; p = 0.01) were associated with reduced CFVR. During a median follow-up time of 16 months, 218 events occurred. RWMA (hazard ratio: 3.8; 95% CI: 2.3 to 6.3; p < 0.001) and reduced CFVR (hazard ratio: 1.5; 95% CI: 1.1 to 2.2; p = 0.009) were independently associated with adverse outcome. CONCLUSIONS: CFVR is feasible with all SE protocols. Reduced CFVR is often accompanied by RWMA, abnormal LVCR, and pulmonary congestion during stress, and shows independent value over RWMA in predicting an adverse outcome.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Ecocardiografia sob Estresse , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Idoso , Velocidade do Fluxo Sanguíneo , Doença da Artéria Coronariana/mortalidade , Feminino , Insuficiência Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos
10.
J Clin Endocrinol Metab ; 93(9): 3325-32, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18593775

RESUMO

CONTEXT: An independent association between obesity and preclinical carotid atherosclerosis has been demonstrated, however, the pathophysiological links were not clearly established. Body composition (BC) influences systemic hemodynamics and may participate in the remodeling of common carotid artery (CCA), independently of risk factors. OBJECTIVE: This study evaluated the association between CCA structure and BC in a large population of healthy subjects. DESIGN: This was a cross-sectional study. SETTINGS: The study was conducted at 19 European centers. SUBJECTS: The study included 627 healthy subjects (252 men, age 30-60 yr, body mass index 17-40 kg/m2). MAIN OUTCOME MEASURES: CCA luminal diameter and intima-media thickness were measured on digitized ultrasound images. Acoustic properties of CCA wall were evaluated by digital densitometric analysis and described in terms of mean gray level. BC was assessed by electrical bioimpedance. Insulin sensitivity (euglycemic hyperinsulinemic clamp) and plasma adiponectin levels were measured. Associations between CCA structure, age, BC, and metabolic and atherosclerotic risk factors were analyzed by multivariate regression models. RESULTS: Independent factors affecting CCA diameter were fat-free mass and waist girth (standardized r = 0.44 and 0.12; P < 0.01 and < 0.0001; R2 = 0.35); independent correlates of intima-media thickness were age, CCA diameter, systolic blood pressure, and low-density lipoprotein-cholesterol (standardized r = 0.39, 0.25, 0.10, and 0.14; P < 0.005-0.0001; R2 = 0.40). The mean gray level of carotid wall was independently associated with age and waist girth (standardized r = 0.23 and 0.12; P < 0.0001 and = 0.001; R2 = 0.30). CONCLUSIONS: Findings of this cross-sectional study suggest that BC modulates CCA diameter, and may induce adaptive changes in carotid wall thickness, independently of metabolic and atherosclerotic factors. Central adiposity modifies the acoustic properties of carotid wall.


Assuntos
Composição Corporal/fisiologia , Artéria Carótida Primitiva/anatomia & histologia , Artéria Carótida Primitiva/fisiologia , Saúde , Adulto , Fatores Etários , Pressão Sanguínea/fisiologia , Doenças das Artérias Carótidas/etiologia , Doenças das Artérias Carótidas/fisiopatologia , Artéria Carótida Primitiva/diagnóstico por imagem , Estudos de Coortes , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Túnica Íntima/diagnóstico por imagem , Túnica Média/diagnóstico por imagem , Ultrassonografia
11.
Stroke ; 38(9): 2549-55, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17656659

RESUMO

BACKGROUND AND PURPOSE: Regular endurance exercise has been shown to reduce the age-related increase in arterial stiffness that is thought to contribute to cardiovascular risk. The aim of this study was to evaluate the influence of age and habitual physical activity on carotid artery wall thickness and stiffness in a population of young to middle-age subjects at low cardiovascular risk. METHODS: The study population consisted of 432 healthy subjects (166 men; mean+/-SD age, 43+/-8 years; range, 30 to 60 years) free of carotid atherosclerosis and with low coronary heart disease risk, as determined by the Framingham prediction score sheet. All subjects underwent B-mode ultrasonography of the extracranial carotid arteries and physical activity assessment by actigraph, an accelerometer capable of monitoring the intensity and duration of body movements. The intima-media thickness of the common carotid artery was measured on ultrasound images, along with systodiastolic changes in luminal diameter, and indices of carotid stiffness were calculated. RESULTS: Intima-media thickness and carotid stiffness increased with age in both men and women (r=0.24 to 0.52, P<0.001). The magnitude of objectively assessed daily physical activity was negatively related to indices of carotid stiffness (r from -0.20 to -0.25, P<0.001) but not to intima-media thickness. In multivariate regression analyses that included several cardiovascular risk factors such as obesity, blood pressure, plasma lipids, and smoking habits, age and physical activity were independently related to carotid stiffness. CONCLUSIONS: This study provides cross-sectional evidence that habitual physical activity is inversely related to the age-dependent increase in carotid wall stiffness in a young to middle-age population at low risk.


Assuntos
Envelhecimento/fisiologia , Doenças Cardiovasculares/fisiopatologia , Atividade Motora , Resistência Vascular/fisiologia , Adulto , Doenças Cardiovasculares/prevenção & controle , Artéria Carótida Primitiva/anatomia & histologia , Artéria Carótida Primitiva/diagnóstico por imagem , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Regressão , Fatores de Risco , Estatística como Assunto , Ultrassonografia
12.
Am J Hypertens ; 20(3): 279-84, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17324740

RESUMO

BACKGROUND: In the hypertensive heart, epicardial arteries are not enlarged, despite increased total coronary flow related to augmented cardiac workload, wall stress, and left ventricular (LV) mass. The aims of this study were to assess the impact of different hemodynamic factors and LV mass on baseline left main coronary artery (LMA) size in hypertensive LV hypertrophy (LVH) and physiologic LVH, used as a pressure-independent model of hypertrophy. METHODS: In 104 subjects without coronary disease (26 normotensive subjects without LVH, 15 athletes with physiologic LVH, and 63 untreated hypertensive subjects [28 without and 35 with LVH]), LMA size and coronary flow reserve (CFR) were measured by transesophageal echocardiography, and LV mass, volumes, stroke work, and wall stress were measured by transthoracic echocardiography. RESULTS: The LMA area in normotensive control subjects, athletes, and hypertensive subjects without and with LVH was 13.2 +/- 4.2, 17.5 +/- 2.9, 10.1 +/- 3.2 and 13.1 +/- 3.9 mm(2). In normotensive control subjects, LMA size increased with body surface area, rate-pressure product, stroke work, and LV mass or wall thickness (r = 0.39, 0.39, 0.47 and 0.67 or 0.62, P < .05-0.01). In athletes with physiologic LVH, LMA area increased with CFR (0.65, P < .01). In the whole hypertensive population, LMA lumen increased with LV mass (r = 0.40, P < .01), and decreased with office systolic blood pressure (r = -0.48, P < .01). CONCLUSIONS: In the hypertensive LVH, baseline LMA area is not increased and is inversely related to office systolic blood pressure. In the physiologic LVH, increase in baseline LMA size seems to reflect effect of high-flow stimuli.


Assuntos
Vasos Coronários/patologia , Exercício Físico , Hipertensão/complicações , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/patologia , Adulto , Pressão Sanguínea , Estudos de Coortes , Circulação Coronária , Ecocardiografia Transesofagiana , Feminino , Ventrículos do Coração/patologia , Humanos , Hipertensão/patologia , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pericárdio , Reprodutibilidade dos Testes , Estudos Retrospectivos
13.
Med Eng Phys ; 29(1): 76-86, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16540362

RESUMO

Several abnormalities of the shape of lung fields (depression and flattening of the diaphragmatic contours, increased retrosternal space) are indicative of emphysema and can be accurately imaged by digital chest radiography. In this work, we aimed at developing computational descriptors of the shape of the lung silhouette able to capture the alterations associated with emphysema. We analyzed two-sided digital chest radiographs from a sample of 160 patients with chronic obstructive pulmonary disease (COPD), 60 of which were affected by emphysema, and from 160 subjects with normal lung function. Two different description schemes were considered: a first one based on lung-silhouette curvature features, and a second one based on a minimal-polyline approximation of the lung shape. Both descriptors were employed to recognize alterations of the lung shape using classifiers based on multilayer neural networks of the feed-forward type. Results indicate that pulmonary emphysema can be reliably diagnosed or excluded by using digital chest radiographs and a proper computational aid. Two-sided chest radiographs provide more accurate discrimination than single-view analysis. The minimal-polyline approximation provided significantly better results than those obtained from curvature-based features. Emphysema was detected, in the entire dataset, with an accuracy of about 90% (sensitivity 88%, specificity 90%) by using the minimal-polyline approximation.


Assuntos
Pulmão/diagnóstico por imagem , Reconhecimento Automatizado de Padrão/métodos , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Enfisema Pulmonar/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Torácica/métodos , Humanos , Redes Neurais de Computação , Doença Pulmonar Obstrutiva Crônica/complicações , Enfisema Pulmonar/etiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Trends Cardiovasc Med ; 27(5): 336-349, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28214110

RESUMO

Nomograms are essential tools for quantification in pediatric echocardiography. In the last few years, multiple sources highlight that nomograms employed for decades presented significant numerical and methodological limitations. As a result, widely different ranges of normality were generated, thus creating confusion in estimation of several cardiac diseases. New nomograms have recently been generated, overcoming some of the gaps of previous research: wider sample sizes (including neonates/infants), solid statistical/methodological plan, and availability of new data (chamber dimensions, many functional parameters). In particular, robust two-dimensional nomograms covering a wide spectrum of cardiac measurements have recently become available. Significant advances have been made for functional data (i.e. diastolic and deformation indexes) but a few limitations still exist. These include numerical issues (sample size of below 400 subjects) and methodological pitfalls (heterogeneous data normalization/expression). Despite these limitations, however, actual nomograms for functional data present quite reproducible intervals of normality with the exception of neonates and infants. In conclusion, great advances have been made during the last years. A few basic rules for the building of nomograms have been established (i.e. inclusion/exclusion criteria, measurement standardization), while others (i.e. the sample size, the way to express/normalize data, statistical requirements) are basically defined but still require standardization. New pediatric echocardiographic nomograms of good quality are easily accessible due to new electronic tools (online calculators, apps for smart-phone/tablets). Studies are ongoing to generate wider, comprehensive and multi-ethnic nomograms and to evaluate new parameters (e.g. three-dimensional parameters).


Assuntos
Cardiologia/métodos , Técnicas de Apoio para a Decisão , Ecocardiografia/métodos , Cardiopatias Congênitas/diagnóstico por imagem , Nomogramas , Pediatria/métodos , Adolescente , Fatores Etários , Cardiologia/normas , Cardiologia/tendências , Criança , Pré-Escolar , Ecocardiografia/normas , Ecocardiografia/tendências , Ecocardiografia Doppler , Ecocardiografia Tridimensional , Previsões , Cardiopatias Congênitas/fisiopatologia , Hemodinâmica , Humanos , Lactente , Recém-Nascido , Contração Miocárdica , Pediatria/normas , Pediatria/tendências , Valor Preditivo dos Testes , Prognóstico , Valores de Referência , Índice de Gravidade de Doença , Função Ventricular Esquerda , Função Ventricular Direita
15.
Ultrasound Med Biol ; 43(11): 2558-2566, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28865726

RESUMO

Various lung ultrasound (LUS) scanning modalities have been proposed for the detection of B-lines, also referred to as ultrasound lung comets, which are an important indication of extravascular lung water at rest and after exercise stress echo (ESE). The aim of our study was to assess the lung water spatial distribution (comet map) at rest and after ESE. We performed LUS at rest and immediately after semi-supine ESE in 135 patients (45 women, 90 men; age 62 ± 12 y, resting left ventricular ejection fraction = 41 ± 13%) with known or suspected heart failure or coronary artery disease. B-lines were measured by scanning 28 intercostal spaces (ISs) on the antero-lateral chest, 2nd-5th IS, along with the midaxillary (MA), anterior axillary (AA), mid-clavicular (MC) and parasternal (PS) lines. Complete 28-region, 16-region (3rd and 4th IS), 8-region (3rd IS), 4-region (3rd IS, only AA and MA) and 1-region (left 3rd IS, MA) scans were analyzed. In each space, the B-lines were counted from 0 = black lung to 10 = white lung. Interpretable images were obtained in all spaces (feasibility = 100 %). B-lines (>0 in at least 1 space) were present at ESE in 93 patients (69%) and absent in 42. More B-lines were found in the 3rd IS and along AA and MA lines. The B-line cumulative distribution was symmetric at rest (right/left = 1.10) and asymmetric with left lung predominance during stress (right/left = 0.67). The correlation of per-patient B-line number between 28-S and 16-S (R2 = 0.9478), 8-S (R2 = 0.9478) and 4-S scan (R2 = 0.9146) was excellent, but only good with 1-S (R2 = 0.8101). The average imaging and online analysis time were 5 s per space. In conclusion, during ESE, the comet map of lung water accumulation follows a predictable spatial pattern with wet spots preferentially aligned with the third IS and along the AA and MA lines. The time-saving 4-region scan is especially convenient during stress, simply dismissing dry regions and focusing on wet regions alone.


Assuntos
Teste de Esforço , Água Extravascular Pulmonar/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Ultrassonografia/métodos , Água Extravascular Pulmonar/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Descanso , Estresse Fisiológico/fisiologia
16.
J Thorac Dis ; 9(12): 5404-5422, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29312752

RESUMO

There is a crescent interest on normal adult echocardiographic values and the introduction of new deformation imaging and 3D parameters pose the issue of normative data. A multitude of nomograms has been recently published, however data are often fragmentary, difficult to find, and their strengths/limitations have been never evaluated. AIMS: (I) to provide a review of current echocardiographic nomograms; (II) to generate a tool for easy and fast access to these data. A literature search was conducted accessing the National Library of Medicine using the keywords: 2D/3D echocardiography, strain, left/right ventricle, atrial, mitral/tricuspid valve, aorta, reference values/nomograms/normal values. Adding the following keywords, the results were further refined: range/intervals, myocardial velocity, strain rate and speckle tracking. Forty one published studies were included. Our study reveals that for several of 2D/3D parameters sufficient normative data exist, however, a few limitations still persist. For some basic parameters (i.e., mitral/tricuspid/pulmonary valves, great vessels) and for 3D valves data are scarce. There is a lack of studies evaluating ethnic differences. Data have been generally expressed as mean values normalised for gender and age instead of computing models incorporating different variables (age/gender/body sizes) to calculate z scores. To summarize results a software (Echocardio-Normal Values) who automatically calculate range of normality for a broad range of echocardiographic measurements according to age/gender/weight/height, has been generated. We provide an up-to-date and critical review of strengths/limitation of current adult echocardiographic nomograms. Furthermore we generated a software for automatic, easy and fast access to multiple echocardiographic normative data.

17.
Int J Cardiovasc Imaging ; 33(11): 1731-1736, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28550586

RESUMO

The diffusion of smart-phones offers access to the best remote expertise in stress echo (SE). To evaluate the reliability of SE based on smart-phone filming and reading. A set of 20 SE video-clips were read in random sequence with a multiple choice six-answer test by ten readers from five different countries (Italy, Brazil, Serbia, Bulgaria, Russia) of the "SE2020" study network. The gold standard to assess accuracy was a core-lab expert reader in agreement with angiographic verification (0 = wrong, 1 = right). The same set of 20 SE studies were read, in random order and >2 months apart, on desktop Workstation and via smartphones by ten remote readers. Image quality was graded from 1 = poor but readable, to 3 = excellent. Kappa (k) statistics was used to assess intra- and inter-observer agreement. The image quality was comparable in desktop workstation vs. smartphone (2.0 ± 0.5 vs. 2.4 ± 0.7, p = NS). The average reading time per case was similar for desktop versus smartphone (90 ± 39 vs. 82 ± 54 s, p = NS). The overall diagnostic accuracy of the ten readers was similar for desktop workstation vs. smartphone (84 vs. 91%, p = NS). Intra-observer agreement (desktop vs. smartphone) was good (k = 0.81 ± 0.14). Inter-observer agreement was good and similar via desktop or smartphone (k = 0.69 vs. k = 0.72, p = NS). The diagnostic accuracy and consistency of SE reading among certified readers was high and similar via desktop workstation or via smartphone.


Assuntos
Ecocardiografia sob Estresse/instrumentação , Aplicativos Móveis , Isquemia Miocárdica/diagnóstico por imagem , Consulta Remota/instrumentação , Smartphone , Brasil , Angiografia Coronária , Europa (Continente) , Estudos de Viabilidade , Humanos , Isquemia Miocárdica/fisiopatologia , Variações Dependentes do Observador , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes
18.
Int J Cardiol ; 249: 479-485, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28986062

RESUMO

BACKGROUND: The trial "Stress Echo (SE) 2020" evaluates novel applications of SE beyond coronary artery disease. The aim of the study was control quality and harmonize reading criteria. METHODS: One reader from 78 centers of the SE 2020 network asked for credentials to read a set of 20 SE video-clips selected by the core lab. All aspiring centers met the pre-requisite of high-volume and the years of experience in SE ranged from 5 to 31years (mean value 18years). The diagnostic gold standard was a reading by the core lab. The a priori determined pass threshold was 18/20 (≥90%). RESULTS: Of the initial 78 who started, 57 completed the first attempt: individual readers' score on first attempt ranged from 07/20 to 20/20 (accuracy from 35% to 100%, mean 78.7±13%) and 44 readers passed it. There was a very poor correlation between years of experience and the reader's score on first attempt (r=-0.161, p=0.231). Of the 13 readers who failed the first attempt, 12 took it again after the web-based session and their accuracy improved (74% vs. 96%, p<0.001). The kappa inter-observer agreement before and after web-based training was 0.59 on first attempt and rose to 0.91 on the last attempt. CONCLUSIONS: In SE reading, the volume of activity or years of experience is not synonymous with diagnostic quality. Qualitative analysis and operator-dependence can become a limiting weakness in clinical practice, in the absence of strict pathways of learning, credentialing and audit.


Assuntos
Cardiologistas/normas , Competência Clínica/normas , Doença das Coronárias/diagnóstico por imagem , Ecocardiografia sob Estresse/normas , Controle de Qualidade , Doença das Coronárias/epidemiologia , Ecocardiografia sob Estresse/métodos , Humanos , Internacionalidade , Reprodutibilidade dos Testes
19.
PLoS One ; 11(4): e0150659, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27070318

RESUMO

INTRODUCTION: The present study was aimed to assess the in vivo hamster pial microvessel alterations due to 30 min transient bilateral common carotid artery occlusion (BCCAO) and reperfusion (60 min); moreover, the neuroprotective effects of Vaccinium myrtillus extract, containing 34.7% of anthocyanins, were investigated. MATERIALS AND METHODS: Two groups of male hamsters were used: the first fed with control diet and the other with Vaccinium myrtillus supplemented diet. Hamster pial microcirculation was visualized by fluorescence microscopy through an open cranial window. Pial arterioles were classified according to Strahler's method. RESULTS: In age-matched control diet-fed hamsters, BCCAO caused a decrease in diameter of all arterioles. At the end of reperfusion, the reduction of diameter in order 3 arterioles was by 8.4 ± 3.1%, 10.8 ± 2.3% and 12.1 ± 1.1% of baseline in the 2, 4 and 6 month control diet-fed hamsters, respectively. Microvascular permeability and leukocyte adhesion were markedly enhanced, while perfused capillary length (PCL) decreased. The response to acetylcholine and papaverine topical application was impaired; 2'-7'-dichlorofluoresceine-diacetate assay demonstrated a significant ROS production. At the end of BCCAO, in age-matched Vaccinium myrtillussupplemented diet-fed hamsters, the arteriolar diameter did not significantly change compared to baseline. After 60 min reperfusion, order 3 arterioles dilated by 9.3 ± 2.4%, 10.6 ± 3.1% and 11.8 ± 2.7% of baseline in the 2, 4 and 6 month Vaccinium myrtillus supplemented diet-fed hamsters, respectively. Microvascular leakage and leukocyte adhesion were significantly reduced in all groups according to the time-dependent treatment, when compared with the age-matched control diet-fed hamsters. Similarly, the reduction in PCL was progressively prevented. Finally, the response to acetylcholine and papaverine topical application was preserved and there was no significant increase in ROS production in all groups. CONCLUSIONS: In conclusion, Vaccinium myrtillusextract protected pial microcirculation during hypoperfusion-reperfusion, preventing vasoconstriction, microvascular permeability, leukocyte adhesion, reduction in PCL and preserving the endothelium function.


Assuntos
Antocianinas/farmacologia , Microcirculação/efeitos dos fármacos , Microvasos/efeitos dos fármacos , Pia-Máter/irrigação sanguínea , Traumatismo por Reperfusão/fisiopatologia , Acetilcolina/farmacologia , Animais , Arteríolas/efeitos dos fármacos , Arteríolas/metabolismo , Permeabilidade Capilar/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Circulação Cerebrovascular/efeitos dos fármacos , Cricetinae , Leucócitos/efeitos dos fármacos , Masculino , Mesocricetus , Microvasos/metabolismo , Fármacos Neuroprotetores/farmacologia , Papaverina/farmacologia , Extratos Vegetais , Espécies Reativas de Oxigênio/metabolismo , Reperfusão/métodos , Vaccinium myrtillus
20.
J Am Soc Echocardiogr ; 15(7): 678-85, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12094165

RESUMO

Quantitative myocardial contrast echocardiography was performed with harmonic power Doppler analysis using the background subtraction and Levovist (Schering AG, Berlin, Germany) as contrast agent in a triggered modality. Quantitative analysis of echocontrast was performed offline with PC software, obtaining the transit curves of microbubbles through the coronary capillary system. Coronary microcirculation in athletes showed a behavior substantially comparable with control participants, although at a higher level. Training determines a physiologic left ventricular hypertrophy that counterbalances the dilatation in the left ventricular chambers because of the higher blood volume in athletes compared with control participants. Angiogenesis and several functional adaptations (relaxation of small coronary arteries, increased production of nitric oxide by the coronary endothelium, or both), represent the potential mechanisms that allow an optimal distribution of oxygen and of substrates to the hypertrophied myocardium of the athletes.


Assuntos
Meios de Contraste , Circulação Coronária , Ecocardiografia Doppler/métodos , Processamento de Imagem Assistida por Computador , Polissacarídeos , Esportes/fisiologia , Adulto , Estudos de Casos e Controles , Circulação Coronária/efeitos dos fármacos , Dipiridamol/farmacologia , Humanos , Microcirculação , Microesferas , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
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