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1.
J Clin Ultrasound ; 45(4): 211-221, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27911009

RESUMO

BACKGROUND: We aimed to assess the relationship between echocardiographic characteristics and mortality in patients with chronic obstructive pulmonary disease (COPD). METHODS: We prospectively studied 154 patients (mean age 71 ± 10 years, 71% male) with COPD. All patients underwent transthoracic Doppler echocardiography within 48 hours of hospital admission. Primary endpoint was all-cause mortality during a median period of 22 months. RESULTS: Mildly elevated tricuspid regurgitation pressure and mitral E/e' ratio were the most commonly encountered echocardiographic abnormalities, observed in 60% and 56% of patients, respectively. In Kaplan-Meier analysis of survival, left atrial enlargement, E/e' ratio > 8, right atrial enlargement, right ventricular dilation, decreased tricuspid annular plane systolic excursion, decreased tricuspid annular systolic velocity, and elevated tricuspid regurgitation velocity were associated with all-cause mortality (p < 0.05 for all). In the Cox proportional hazards analysis, the mitral E/e' ratio (hazard ratio 1.048; 95% confidence interval 1.001-1.096) remained an independent echocardiographic predictor of survival after adjustment for age, COPD severity, and other baseline echocardiographic parameters. CONCLUSIONS: Among patients with COPD, an abnormal mitral E/e' ratio was an independent echocardiographic predictor of all-cause mortality. Echocardiographic evaluation of structural and functional cardiac abnormalities provides important prognostic information and should be used routinely in the assessment of patients with COPD. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:211-221, 2017.


Assuntos
Ecocardiografia Doppler/métodos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Insuficiência da Valva Tricúspide/fisiopatologia , Disfunção Ventricular/diagnóstico por imagem , Disfunção Ventricular/fisiopatologia , Idoso , Feminino , Seguimentos , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/patologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Tamanho do Órgão , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Eslovênia , Volume Sistólico/fisiologia , Insuficiência da Valva Tricúspide/complicações , Disfunção Ventricular/complicações
2.
Polymers (Basel) ; 16(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38674953

RESUMO

This study presents an analysis of films which consist of two layers; one layer is PVDF as the matrix, along with fillers BaTiO3 (BT), and the second is one bacterial nanocellulose (BNC) filled with Fe3O4. The mass fraction of BT in PVDF was 5%, and the samples were differentiated based on the duration of the mechanical activation of BT. This innovative PVDF laminate polymer with environmentally friendly fillers aligns with the concept of circular usage, resulting in a reduction in plastic content and potential improvement of the piezoelectric properties of the entire composite. This work presents new, multifunctional "green" packaging materials that potentially could be a good alternative to specific popular materials used for this purpose. The synthesis of the films was carried out using the hot press method. Tensile tests, water vapor permeability examination, and structural analyses using SEM-EDS and FTIR have been conducted. The sample PVDF/BT20/BNC/Fe3O4 exhibited the best barrier properties (impermeability to water vapor), while the highest tensile strength and toughness were exhibited by the PVDF/BT5/BNC/Fe3O4 sample.

3.
Polymers (Basel) ; 15(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37896324

RESUMO

In the search for environmentally friendly materials with a wide range of properties, polymer composites have emerged as a promising alternative due to their multifunctional properties. This study focuses on the synthesis of composite materials consisting of four components: bacterial nanocellulose (BNC) modified with magnetic Fe3O4, and a mixture of BaTiO3 (BT) and polyvinylidene fluoride (PVDF). The BT powder was mechanically activated prior to mixing with PVDF. The influence of BT mechanical activation and BNC with magnetic particles on the PVDF matrix was investigated. The obtained composite films' structural characteristics, morphology, and dielectric properties are presented. This research provides insights into the relationship between mechanical activation of the filler and structural and dielectric properties in the PVDF/BT/BNC/Fe3O4 system, creating the way for the development of materials with a wide range of diverse properties that support the concept of green technologies.

4.
Polymers (Basel) ; 14(9)2022 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-35566987

RESUMO

The rise of innovation in the electrical industry is driven by the controlled design of new materials. The hybrid materials based on magnetite/nanocellulose are highly interesting due to their various applications in medicine, ecology, catalysis and electronics. In this study, the structure and morphology of nanocellulose/magnetite hybrid nanomaterials were investigated. The effect of nanocellulose loading on the crystal structure of synthesized composites was investigated by XRD and FTIR methods. The presented study reveals that the interaction between the cellulose and magnetic nanoparticles depends on the nanocellulose content. Further, a transition from cellulose II to cellulose I allomorph is observed. SEM and EDS are employed to determine the variation in morphology with changes in component concentrations. By the calculation of magnetic interactions between adjacent Fe3+ and Fe2+ ions within composites, it is determined that ferromagnetic coupling predominates.

6.
Ann Med ; 50(2): 128-138, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28972811

RESUMO

OBJECTIVES: Bundle branch blocks (BBB)-related mechanical dyssynchrony and dispersion may improve patient selection for device therapy, but their effect on the natural history of this patient population is unknown. METHODS: A total of 155 patients with LVEF ≤ 35% and BBB, not treated with device therapy, were included. Mechanical dyssynchrony was defined as the presence of either septal flash or apical rocking. Contraction duration was assessed as time interval from the electrocardiographic R-(Q-)wave to peak longitudinal strain in each of 17 left ventricular segments. Mechanical dispersion was defined as either the standard deviation of all time intervals (dispersionSD) or as the difference between the longest and shortest time intervals (dispersiondelta). Patients were followed for cardiac mortality during a median period of 33 months. RESULTS: Mechanical dyssynchrony was not associated with survival. More pronounced mechanical dispersiondelta was found in patients with dyssynchrony than in those without. In the multivariate regression analysis, patients' functional class, diabetes mellitus and dispersiondelta were independently associated with mortality. CONCLUSIONS: Mechanical dispersion, but not dyssynchrony, was independently associated with mortality and it may be useful for risk stratification of patients with heart failure (HF) and BBB. Key Messages Mechanical dispersion, measured by strain echocardiography, is associated with poor outcome in heart failure with a severely depressed left ventricular function and bundle branch blocks. Mechanical dispersion may be useful for risk stratification of patients with heart failure and bundle branch blocks.


Assuntos
Bloqueio de Ramo/fisiopatologia , Insuficiência Cardíaca/mortalidade , Ventrículos do Coração/fisiopatologia , Fatores Etários , Idoso , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/mortalidade , Ecocardiografia , Eletrocardiografia , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Medição de Risco/métodos , Volume Sistólico/fisiologia , Análise de Sobrevida , Função Ventricular Esquerda/fisiologia
7.
Int J Cardiovasc Imaging ; 33(10): 1541-1549, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28551719

RESUMO

Some patients with unstable angina and critical stenosis of the left anterior descending coronary artery (LAD) present with Wellens syndrome (WS), i.e., inverted or biphasic T-waves in the anterior precordial leads. We assessed clinical, angiographic, electro- and echocardiographic characteristic of patients with WS. In this retrospective study, clinical, angiographic, electro- and echocardiographic characteristic of 35 patients with WS were compared to 57 patients with critical LAD stenosis and normal resting electrocardiogram (ECG), and 45 subjects with normal coronary angiogram. QTc dispersion was measured from the 12-lead ECG as the difference between longest and shortest QTc intervals. Mechanical dispersion was defined as the time difference between the longest and shortest contraction durations which were measured as the time from the first deflection of the QRS complex to maximum myocardial shortening of each 18 segmental longitudinal strain curves derived by speckle tracking echocardiography. There were no significant differences in the complexity and location of the LAD lesion, anterograde and collateral flow in LAD and coronary artery dominance between patients with WS and normal ECG (P > 0.05, for all). Patients with WS had lower global longitudinal strain (GLS) and more pronounced both QTc and myocardial mechanical dispersion than patients with critical LAD stenosis and normal ECG, and control subjects (P < 0.05). T-wave changes in patients with WS are associated with more profound regional myocardial dysfunction and increased QTc and myocardial mechanical dispersion. Similar angiographic characteristics of the LAD lesion were seen in patients with WS and normal ECG.


Assuntos
Angina Instável/diagnóstico , Estenose Coronária/diagnóstico , Eletrocardiografia , Sistema de Condução Cardíaco/fisiopatologia , Potenciais de Ação , Idoso , Angina Instável/fisiopatologia , Circulação Colateral , Angiografia Coronária , Circulação Coronária , Estenose Coronária/fisiopatologia , Estado Terminal , Ecocardiografia , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença , Síndrome
8.
Srp Arh Celok Lek ; 144(1-2): 23-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27276854

RESUMO

INTRODUCTION: Data on effects of thrombus aspiration on left ventricular diastolic function in ST-elevation myocardial infarction (STEMI) population are scarce. OBJECTIVE: We sought to compare echocardiographic indices of the diastolic function and outcomes in STEMI patients treated with and without manual thrombus aspiration, in an academic, high-volume percutaneous coronary intervention (PCI) center. METHODS: A total of 433 consecutive patients who underwent primary PCI in 2011-2012 were enrolled in the study. Patients were not eligible for the study if they already suffered a myocardial infarction, had been previously revascularized, received thrombolytics, presented with cardiogenic shock, had significant valvular disease, atrial fibrillation or had previously implanted pacemaker. Comprehensive echocardiogram was performed within 48 hours. During follow-up patients'status was assessed by an office visit or telephone interview. RESULTS: Patients treated with thrombus aspiration (TA+, n=216) had similar baseline characteristics as those without thrombus aspiration (TA-, n = 217). Groups had similar total ischemic time (319 ± 276 vs. 333 ± 372 min; p = 0.665), but TA+ group had higher maximum values of troponin I (39.5 ± 30.5 vs. 27.6 ± 26.9 ng/ml; p < 0.001). The echocardiography revealed similar left ventricular volumes and systolic function, but TA+ group had significantly higher incidence of E/e' > 15, as a marker of severe diastolic dysfunction' (TA+ 23.1% vs. TA- 15.2%; p = 0.050). During average follow-up of 14 ± 5 months, major adverse cardiac/cerebral events occurred at the similar rate (log rank p = 0.867). CONCLUSION: Thrombus aspiration is associated with a greater incidence of severe diastolic dysfunction in unselected STEMI patients treated with primary PCI, but it doesn't influence the incidence of major adverse cardiovascular events.


Assuntos
Pressão Sanguínea/fisiologia , Infarto do Miocárdio/cirurgia , Paracentese , Intervenção Coronária Percutânea , Trombose/cirurgia , Função Ventricular Esquerda/fisiologia , Humanos
9.
Eur Heart J Cardiovasc Imaging ; 16(9): 1015-22, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25762558

RESUMO

AIMS: Ischaemic but viable myocardium may exhibit prolongation of contraction and QT interval duration, but it is largely unknown whether non-invasive assessment of regional heterogeneities of myocardial deformation and QT interval duration could identify patients with significant coronary artery disease (CAD). METHODS AND RESULTS: We retrospectively studied 205 patients with suspected CAD who underwent coronary angiography. QTc dispersion was assessed from a 12-lead electrocardiogram (ECG) as the difference between the longest and shortest QTc intervals. Contraction duration was assessed as time from the ECG R-(Q-)wave to peak longitudinal strain in each of 18 left ventricular segments. Mechanical dispersion was defined as either the standard deviation of 18 time intervals (dispersionSD18) or as the difference between the longest and shortest time intervals (dispersiondelta). Longitudinal strain was measured by speckle tracking echocardiography. Mean contraction duration was longer in patients with significant CAD compared with control subjects (428 ± 51 vs. 410 ± 40 ms; P = 0.032), and it was correlated to QTc interval duration (r = 0.47; P < 0.001). In contrast to QTc interval duration and dispersion, both parameters of mechanical dispersion were independently associated with CAD (P < 0.001) and had incremental value over traditional risk factors, wall motion abnormalities, and global longitudinal strain (GLS) for the detection of significant CAD. CONCLUSION: The QTc interval and myocardial contraction duration are related to the presence of significant CAD in patients without a history of previous myocardial infarction. Myocardial mechanical dispersion has an incremental value to GLS for identifying patients with significant CAD.


Assuntos
Doença da Artéria Coronariana/diagnóstico , Ecocardiografia/métodos , Eletrocardiografia/métodos , Contração Miocárdica/fisiologia , Isquemia Miocárdica/diagnóstico , Fatores Etários , Idoso , Análise de Variância , Estudos de Casos e Controles , Doença da Artéria Coronariana/mortalidade , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Isquemia Miocárdica/mortalidade , Variações Dependentes do Observador , Prognóstico , Curva ROC , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Estatísticas não Paramétricas , Taxa de Sobrevida
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