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1.
Clin Nutr ESPEN ; 32: 145-152, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31221280

RESUMO

BACKGROUND: We tested the hypothesis that a normal sodium diet could be associated with preservation of serum sodium during treatment of acute decompensated heart failure (ADHF). METHODS AND RESULTS: Forty-four patients hospitalized for ADHF were blindly randomized by using block method to a low sodium diet (LS: 3 g/day of dietary sodium chloride; n = 22, 59.5 ± 11.9 y.o., 50% males. LVEF = 30.0 ± 13.6%); and a normal sodium diet (NS: 7 g/day; n = 22, 56.4 ± 10.3 y.o., 68% males; LVEF = 27.8 ± 11.7%), and both groups were submitted to fluid restriction of 1.000 mL/day. At the 7th day of intervention 16 patients of LS group and 15 patients of NS group were assessed for difference in serum sodium. Both groups had equivalent decongestion, reflected by similar percent reduction of body weight (LS: -5.0 ± 4.7% vs NS: -4.5 ± 5.2%. p = 0.41). Reduction of the N terminal fragment of type B natriuretic peptide (NT-proBNP) was significant only in the NS (-1497.0 [-18843.0 - 1191.0]. p = 0.04). The LS group showed lower levels of serum sodium (135.4 ± 3.5 mmol/L) compared to the NS group (137.5 ± 1.9 mmol/L; p = 0.04). Four cases of hyponatremia were observed only in the LS group (22%). The NS group exhibited higher mean blood pressure values (79.4 ± 2.4 mmHg vs 75.5 ± 3.0 mmHg. p = 0.03), and lower heart rate (73.2 ± 1.6 bpm vs 75.5 ± 2.1 bpm. p = 0.02). CONCLUSIONS: These results suggest that a normal sodium diet, when compared to a low sodium diet, is associated with similar degrees of decongestion, but with higher levels of natremia, blood pressure and lower neurohormonal activation during ADHF treatment. TRIAL REGISTRATION: clinicaltrials.gov Identifier no. NCT03722069.

2.
Arq Bras Cardiol ; 111(3): 436-539, 2018 Sep.
Artigo em Português | MEDLINE | ID: mdl-30379264
3.
Rev Bras Enferm ; 71(5): 2404-2410, 2018 Sep-Oct.
Artigo em Inglês, Português | MEDLINE | ID: mdl-30304169

RESUMO

OBJECTIVE: To compare the distributions of measurements of the Dutch Fatigue Scale (DUFS), Dutch Exertion Fatigue Scale (DEFS), and Fatigue Pictogram tools, according to the New York Heart Association (NYHA) Functional Classification and left ventricular ejection fraction (LVEF). METHOD: Methodological, cross-sectional study with 118 patients with heart failure. Variance analysis, Pearson's correlation, and Fisher's exact tests were carried out, with a significance level of 0.05. RESULTS: There was an increase in the DUFS and DEFS means with worsening of the NYHA-FC (p<0.001, for both tools). Correlations among the LVEF resulted in positive and weak magnitude for the DEFS (r=0.18; p=0.05) and for the DUFS (r=0.16; p=0.08). Just the item A on the Fatigue Pictogram had an association with the NYHA-FC (p<0.001) and the LVEF (p=0.03). CONCLUSION: Three tools detected worsening in fatigue levels according to the illness severity assessed by the NYHA-FC.

4.
Rev. bras. enferm ; 71(5): 2404-2410, Sep.-Oct. 2018. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-958693

RESUMO

ABSTRACT Objective: To compare the distributions of measurements of the Dutch Fatigue Scale (DUFS), Dutch Exertion Fatigue Scale (DEFS), and Fatigue Pictogram tools, according to the New York Heart Association (NYHA) Functional Classification and left ventricular ejection fraction (LVEF). Method: Methodological, cross-sectional study with 118 patients with heart failure. Variance analysis, Pearson's correlation, and Fisher's exact tests were carried out, with a significance level of 0.05. Results: There was an increase in the DUFS and DEFS means with worsening of the NYHA-FC (p<0.001, for both tools). Correlations among the LVEF resulted in positive and weak magnitude for the DEFS (r=0.18; p=0.05) and for the DUFS (r=0.16; p=0.08). Just the item A on the Fatigue Pictogram had an association with the NYHA-FC (p<0.001) and the LVEF (p=0.03). Conclusion: Three tools detected worsening in fatigue levels according to the illness severity assessed by the NYHA-FC.


RESUMEN Objetivo: Comparar las distribuciones de medidas de los instrumentos Dutch Fatigue Scale (DUFS), Dutch Exertion Fatigue Scale (DEFS) y Pictograma de Fatiga, según la Clase Funcional de la New York Heart Association (CF-NYHA), y la fracción de eyección del ventrículo izquierdo (FEVE). Método: Estudio metodológico, transversal, con 118 pacientes con insuficiencia cardíaca. Fueron realizados los tests Análisis de Varianza, Correlación de Pearson y Exacto de Fisher, nivel de significatividad de 0,05. Resultados: Hubo aumentos en los promedios del DUFS y del DEFS, empeorando la CF-NYHA (p<0,001 en ambos instrumentos). Las correlaciones entre FEVE fueron de magnitud positiva a débil para DEFS (r=0,18; p=0,05) y para DUFS (r=0,16; p=0,08). Solo el ítem A del Pictograma de Fatiga tuvo asociación con la CF-NYHA (p<0,001) y con la FEVE (p=0,03). Conclusión: Los tres instrumentos detectaron empeoramiento de niveles de fatiga de acuerdo con la enfermedad evaluada por la CF-NYHA.


RESUMO Objetivo: Comparar as distribuições das medidas dos instrumentos Dutch Fatigue Scale (DUFS), Dutch Exertion Fatigue Scale (DEFS) e Pictograma de Fadiga, segundo a Classe Funcional da New York Heart Association (CF-NYHA) e a Fração de Ejeção do Ventrículo Esquerdo (FEVE). Método: Estudo metodológico, transversal, com 118 pacientes com insuficiência cardíaca. Foram realizados os testes Análise de Variância, Correlação de Pearson e Exato de Fisher, com nível de significância de 0,05. Resultados: Houve aumento nas médias do DUFS e do DEFS com a piora da CF-NYHA (p<0,001, para ambos os instrumentos). As correlações entre a FEVE foram de positiva e fraca magnitude para o DEFS (r=0,18; p=0,05) e para o DUFS (r=0,16; p=0,08). Somente o item A do Pictograma de Fadiga teve associação com a CF-NYHA (p<0,001) e com a FEVE (p=0,03). Conclusão: Os três instrumentos detectaram piora nos níveis de fadiga, de acordo com a gravidade da doença avaliada pela CF-NYHA.

5.
J Nucl Cardiol ; 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29696485

RESUMO

BACKGROUND: The relationship between microvasculopathy, autonomic denervation, and myocardial fibrosis, in Chagas cardiomyopathy is incompletely understood. The aim of this study was to explore the relative extent and anatomic distribution of myocardial hypoperfusion, autonomic denervation, and myocardial scarring using Single-Photon Emission Computerized Tomography (SPECT) imaging and Magnetic Resonance Imaging (MRI). METHODS: Thirteen patients with Chagas disease all had Iodine-123-metaiodobenzylguanidine (MIBG) SPECT, 99mTc-Sestamibi (MIBI) rest-stress SPECT, and gadolinium late enhancement MRI imaging within a 2-month interval. The anatomic location and extent of denervation, of stress-induced hypoperfusion and fibrosis, were assessed through image co-registration and quantification of abnormal tissue areas as a percent of total myocardium. RESULTS: The results showed a strong general anatomic concordance between areas of hypoperfusion, denervation, and fibrosis, suggesting that the three abnormal features may be correlated. Myocardial denervation was anatomically and quantitatively closely associated areas of stress hypoperfusion. CONCLUSION: Combined myocardial analysis of the extent and location of autonomic denervation, hypoperfusion, and scarring may allow for better understanding of the pathophysiology of Chagas cardiomyopathy. Autonomic myocardial denervation may be a more sensitive marker of cardiac involvement in Chagas Disease than finding by other imaging modalities.

6.
J Nucl Med ; 59(9): 1430-1436, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29700129

RESUMO

Altered myocardial perfusion is a common finding in chronic Chagas cardiomyopathy (CCC), but its underlying histologic changes have not been elucidated. We investigated the occurrence of myocardial perfusion defects (MPDs) and the correlated regional changes to histology in an experimental model of CCC in hamsters. Methods: Female Syrian hamsters (n = 34) were infected with 3.5 × 104 to 105 trypomastigote forms of Trypanosoma cruzi, Y strain, and 6-10 mo afterward underwent in vivo imaging including resting 99mTc-sestamibi SPECT, segmental and global left ventricular function assessment using 2-dimensional echocardiography, and 18F-FDG PET for evaluation of myocardial viability. Histologic analysis included quantification of fibrosis, inflammatory infiltration, and the diameter and density of myocardial microcirculation. Results: MPDs were present in 17 (50%) of the infected animals. Histologic analysis revealed no transmural scar in segments with an MPD, and normal or mildly reduced 18F-FDG uptake, indicating viable myocardium. Infected animals with an MPD, in comparison to infected animals without an MPD and control animals, showed a lower left ventricular ejection fraction (P = 0.012), a higher wall motion score index (P = 0.004), and a higher extent of inflammatory infiltration (P = 0.018) but a similar extent of fibrosis (P = 0.15) and similar microvascular diameter and density (P > 0.05). Segments with an MPD (n = 65), as compared with normally perfused regions in the same animal (n = 156), showed a higher wall motion score index (P = 0.005) but a similar extent of inflammatory infiltration, a similar extent of fibrosis, and a similar microvascular diameter and density. Conclusion: Resting MPDs are frequent in experimental CCC and are associated with myocardial inflammation but do not designate scar tissue, corresponding to regions with metabolically viable myocardium.

7.
Clin Nutr ; 2018 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-29551406

RESUMO

INTRODUCTION: Heart failure (HF) is a growing public health issue; its risk factors include inappropriate dietary intake of microelements such as iodine, selenium, zinc and iron, which may lead to thyroid dysfunction. OBJECTIVE: This study aimed to assess the correlation among the functional class stages of patients with HF, iodine, selenium, iron and zinc levels with the presence of thyroid dysfunction. METHODOLOGY: One hundred nine patients from the HF outpatient clinic of the Clinics Hospital of Ribeirão Preto whose blood and urine were collected for micronutrient analysis and laboratory tests were selected. The subjects' weight and height were also measured to calculate their BMI. First, a descriptive analysis of the data was made into tables, and then statistical analyses were done at a 5% significance level (p < 0.05). RESULTS: Most patients whose data was analysed were elderly and overweight. Excess ioduria, serum selenium and zinc, erythrocyte zinc and deficiency in serum iron and erythrocyte selenium were observed. The prevalence of thyroid dysfunction was 8.3%. Multivariate logistic regression verified that thyroid dysfunction increases the chance of classification in functional class III or IV (p = 0.015; OR = 8.72) by 8.7 times; each year of age increases the chance by 4.6% of classification in functional class III or IV (p = 0.008; odds ratio [OR] = 1.05), and each unit of BMI increases the chance of classification in functional class III or IV by 9.2% (p = 0.028; OR = 1.09). CONCLUSION: Patients with HF were deficient in serum iron and erythrocyte selenium. No connection was found between hypothyroidism and mineral deficiency, which seems to be related more to the severity of the disease than to the micronutrient nutritional profile.

8.
Int. j. cardiovasc. sci. (Impr.) ; 31(2): f:173-l:189, mar.-abr. 2018. ilus, tab, graf
Artigo em Português | LILACS | ID: biblio-882961

RESUMO

A cardiomiopatia crônica da doença de Chagas (CCDC) é resultante de miocardite fibrosante focal de baixa intensidade, mas incessante, causada pela infecção persistente do T cruzi, associada à inflamação mediada por mecanismos imunes adversos. Cerca de 30% dos infectados desenvolvem, ao longo da vida, a forma crônica cardíaca da doença de Chagas com manifestação clínica proteiforme, que pode incluir morte súbita, sintomas e sinais de insuficiência cardíaca, eventos cardioembólicos, arritmia e sintomas anginoides. A morte súbita e a progressão da insuficiência cardíaca (IC) são os mecanismos mais comuns de óbito nesta condição. Os aspectos prognósticos mais relevantes são sintomas de IC avançada (CF III/IV da NYHA), cardiomegalia, disfunção sistólica do VE e taquicardia ventricular não sustentada. A prevenção dos eventos cardioembólicos é aspecto importante no manejo dos pacientes com CCDC. Agentes anticoagulantes orais devem ser indicados para pacientes com risco elevado, conforme a presença de um conjunto de fatores de risco: disfunção sistólica do VE, aneurisma apical, alteração da repolarização ventricular ao ECG e idade avançada. O tratamento da IC na CCDC segue os mesmos princípios aplicados à IC secundária à cardiomiopatia dilatada de outras etiologias


Assuntos
Humanos , Masculino , Feminino , Cardiomiopatias/mortalidade , Cardiomiopatia Chagásica/mortalidade , Doença de Chagas/epidemiologia , Doença de Chagas/mortalidade , Morte Súbita , Ecocardiografia/métodos , Eletrocardiografia Ambulatorial/métodos , Eletrocardiografia/métodos , Espectroscopia de Ressonância Magnética/métodos , Valva Mitral , Valva Tricúspide , Trypanosoma cruzi/parasitologia
9.
J Nucl Cardiol ; 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29392628

RESUMO

BACKGROUND: Myocardial perfusion defects (MPD) due to coronary microvascular dysfunction is frequent in chronic Chagas cardiomyopathy (CCC) and may be involved with development of myocardial damage. We investigated whether MPD precedes left ventricular systolic dysfunction and tested the hypothesis that prolonged use of dipyridamole (DIPY) could reduce MPD in an experimental model of CCC in hamsters. METHODS AND RESULTS: We investigated female hamsters 6-months after T. cruzi infection (baseline condition) and control animals, divided into T. cruzi-infected animals treated with DIPY (CH + DIPY) or placebo (CH + PLB); and uninfected animals treated with DIPY (CO + DIPY) or placebo (CO + PLB). The animals were submitted to echocardiogram and rest SPECT-Sestamibi-Tc99m myocardial perfusion scintigraphy. Next, the animals were treated with DIPY (4 mg/kg bid, intraperitoneal) or saline for 30 days, and reevaluated with the same imaging methods. At baseline, the CH + PLB and CH + DIPY groups showed larger areas of perfusion defect (13.2 ± 13.2% and 17.3 ± 13.2%, respectively) compared with CO + PLB and CO + DIPY (3.8 ± 2.2% e 3.5 ± 2.7%, respectively), P < .05. After treatment, we observed: reduction of perfusion defects only in the CH + DIPY group (17.3 ± 13.2% to 6.8 ± 7.6%, P = .001) and reduction of LVEF in CH + DIPY and CH + PLB groups (from 65.3 ± 9.0% to 53.6 ± 6.9% and from 69.3 ± 5.0% to 54.4 ± 8.6%, respectively, P < .001). Quantitative histology revealed greater extents of inflammation and interstitial fibrosis in both Chagas groups, compared with control group (P < .001), but no difference between Chagas groups (P > .05). CONCLUSIONS: The prolonged use of DIPY in this experimental model of CCC has reduced the rest myocardial perfusion defects, supporting the notion that those areas correspond to viable hypoperfused myocardium.

11.
J Nucl Cardiol ; 25(1): 75-83, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27381340

RESUMO

BACKGROUND: To investigate the correlation between the extent of myocardial sympathetic denervation and fibrosis and the presence of degrees of severity of ventricular arrhythmias in chronic Chagas cardiomyopathy (CCC). METHODS: Forty-three CCC patients with left ventricular ejection fraction (LVEF) ≥ 35% were divided into three groups: SVT group-presenting Sustained Ventricular Tachycardia (SVT) (n = 15), NSVT group-exhibiting episodes of non-SVT (NSVT) on 24-h Holter monitoring (n = 11), and Control group-exhibiting neither SVT nor episodes of NSVT (n = 17). The patients underwent SPECT imaging for myocardial sympathetic innervation with 123Iodine-MIBG (MIBG) and myocardial perfusion with 99mTc-Sestamibi (MIBI) for the evaluation of regional myocardial fibrosis. RESULTS: The summed rest perfusion scores were similar in the three groups. The summed difference score between MIBG and MPI images, which evaluated the extent of denervated but viable myocardium, was significantly higher in SVT group (20.0 ± 8.0) as compared with the control group (2.0 ± 5.0, P < .0001) and with the NSVT group (11.0 ± 8.0, P < .05). CONCLUSIONS: The occurrence of ventricular arrhythmias of different degrees of severity correlates quantitatively with the extent of cardiac sympathetic denervation, but not with the extent of fibrosis, suggesting that myocardial sympathetic denervation plays a major role in triggering ventricular arrhythmia in CCC.

12.
Eur Heart J Cardiovasc Imaging ; 19(4): 459-460n, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29029074

RESUMO

Aims: To develop a document by Brazilian Cardiovascular Imaging Department (DIC) and the European Association of Cardiovascular Imaging (EACVI) to review and summarize the most recent evidences about the non-invasive assessment of patients with Chagas disease, with the intent to set up a framework for standardized cardiovascular imaging to assess cardiovascular morphologic and functional disturbances, as well as to guide the subsequent process of clinical decision-making. Methods and results: Chagas disease remains one of the most prevalent infectious diseases in Latin America, and has become a health problem in non-endemic countries. Dilated cardiomyopathy is the most severe manifestation of Chagas disease, which causes substantial disability and early mortality in the socially most productive population leading to a significant economical burden. Prompt and correct diagnosis of Chagas disease requires specialized clinical expertise to recognize the unique features of this disease. The appropriate and efficient use of cardiac imaging is pivotal for diagnosing the cardiac involvement in Chagas disease, to stage the disease, assess patients' prognosis and address management. Echocardiography is the most common imaging modality used to assess, and follow-up patients with Chagas disease. The presence of echocardiographic abnormalities is of utmost importance, since it allows to stage patients according to disease progression. In early stages of cardiac involvement, echocardiography may demonstrate segmental left ventricuar wall motion abnormalities, mainly in the basal segments of inferior, inferolateral walls, and the apex, which cannot be attributed to obstructive coronary artery arteries. The prevalence of segmental wall motion abnormalities varies according to the stage of the disease, reaching about 50% in patients with left ventricular dilatation and dysfunction. Speckle tracking echocardiography allows a more precise and quantitative measurement of the regional myocardial function. Since segmental wall motion abnormalities are frequent in Chagas disease, speckle tracking echocardiography may have an important clinical application in these patients, particularly in the indeterminate forms when abnormalities are more subtle. Speckle tracking echocardiography can also quantify the heterogeneity of systolic contraction, which is associated with the risk of arrhythmic events. Three-dimensional (3D) echocardiography is superior to conventional two-dimensional (2D) echocardiography for assessing more accurately the left ventricular apex and thus to detect apical aneurysms and thrombus in patients in whom ventricular foreshortening is suspected by 2D echocardiography. In addition, 3D echocardiography is more accurate than 2D Simpson s biplane rule for assessing left ventricular volumes and function in patients with significant wall motion abnormalities, including aneurysms with distorted ventricular geometry. Contrast echocardiography has the advantage to enhancement of left ventricular endocardial border, allowing for more accurate detection of ventricular aneurysms and thrombus in Chagas disease. Diastolic dysfunction is an important hallmark of Chagas disease even in its early phases. In general, left ventricular diastolic and systolic dysfunction coexist and isolated diastolic dysfunction is uncommon but may be present in patients with the indeterminate form. Right ventricular dysfunction may be detected early in the disease course, but in general, the clinical manifestations occur late at advanced stages of Chagas cardiomyopathy. Several echocardiographic parameters have been used to assess right ventricular function in Chagas disease, including qualitative evaluation, myocardial performance index, tissue Doppler imaging, tricuspid annular plane systolic excursion, and speckle tracking strain. Cardiac magnetic resonance (CMR) is useful to assess global and regional left ventricular function in patients with Chagas diseases. Myocardial fibrosis is a striking feature of Chagas cardiomyopathy and late gadolinium enhancement (LGE) is used to detect and quantify the extension of myocardial fibrosis. Myocardial fibrosis might have a role in risk stratification of patients with Chagas disease. Limited data are available regarding right ventricular function assessed by CMR in Chagas disease. Radionuclide ventriculography is used for global biventricular function assessment in patients with suspected or definite cardiac involvement in Chagas disease with suboptimal acoustic window and contraindication to CMR. Myocardial perfusion scintigraphy may improve risk stratification to define cardiac involvement in Chagas disease, especially in the patients with devices who cannot be submitted to CMR and in the clinical setting of Chagas patients whose main complaint is atypical chest pain. Detection of reversible ischemic defects predicts further deterioration of left ventricular systolic function and helps to avoid unnecessary cardiac catheterization and coronary angiography. Conclusion: Cardiac imaging is crucial to detect the cardiac involvement in patients with Chagas disease, stage the disease and stratify patient risk and address management. Unfortunately, most patients live in regions with limited access to imaging methods and point-of-care, simplified protocols, could improve the access of these remote populations to important information that could impact in the clinical management of the disease. Therefore, there are many fields for further research in cardiac imaging in Chagas disease. How to better provide an earlier diagnosis of cardiac involvement and improve patients risk stratification remains to be addressed using different images modalities.

14.
Arq Bras Cardiol ; 108(1): 12-20, 2017 Jan.
Artigo em Português, Inglês | MEDLINE | ID: mdl-28146205

RESUMO

BACKGROUND: Radionuclide ventriculography (RV) is a validated method to evaluate the left ventricular systolic function (LVSF) in small rodents. However, no prior study has compared the results of RV with those obtained by other imaging methods in this context. OBJECTIVES: To compare the results of LVSF obtained by RV and echocardiography (ECHO) in an experimental model of cardiotoxicity due to doxorubicin (DXR) in rats. METHODS: Adult male Wistar rats serving as controls (n = 7) or receiving DXR (n = 22) in accumulated doses of 8, 12, and 16 mg/kg were evaluated with ECHO performed with a Sonos 5500 Philips equipment (12-MHz transducer) and RV obtained with an Orbiter-Siemens gamma camera using a pinhole collimator with a 4-mm aperture. Histopathological quantification of myocardial fibrosis was performed after euthanasia. RESULTS: The control animals showed comparable results in the LVSF analysis obtained with ECHO and RV (83.5 ± 5% and 82.8 ± 2.8%, respectively, p > 0.05). The animals that received DXR presented lower LVSF values when compared with controls (p < 0.05); however, the LVSF values obtained by RV (60.6 ± 12.5%) were lower than those obtained by ECHO (71.8 ± 10.1%, p = 0.0004) in this group. An analysis of the correlation between the LVSF and myocardial fibrosis showed a moderate correlation when the LVSF was assessed by ECHO (r = -0.69, p = 0.0002) and a stronger correlation when it was assessed by RV (r = -0.79, p < 0.0001). On multiple regression analysis, only RV correlated independently with myocardial fibrosis. CONCLUSION: RV is an alternative method to assess the left ventricular function in small rodents in vivo. When compared with ECHO, RV showed a better correlation with the degree of myocardial injury in a model of DXR-induced cardiotoxicity.


Assuntos
Ecocardiografia , Ventriculografia com Radionuclídeos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda , Animais , Antibióticos Antineoplásicos , Cardiotoxicidade/diagnóstico por imagem , Modelos Animais de Doenças , Doxorrubicina , Fibrose , Masculino , Ratos Wistar , Valores de Referência , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Disfunção Ventricular Esquerda/induzido quimicamente , Disfunção Ventricular Esquerda/patologia , Função Ventricular Esquerda/efeitos dos fármacos
15.
Arq. bras. cardiol ; 108(1): 12-20, Jan. 2017. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-838670

RESUMO

Abstract Background: Radionuclide ventriculography (RV) is a validated method to evaluate the left ventricular systolic function (LVSF) in small rodents. However, no prior study has compared the results of RV with those obtained by other imaging methods in this context. Objectives: To compare the results of LVSF obtained by RV and echocardiography (ECHO) in an experimental model of cardiotoxicity due to doxorubicin (DXR) in rats. Methods: Adult male Wistar rats serving as controls (n = 7) or receiving DXR (n = 22) in accumulated doses of 8, 12, and 16 mg/kg were evaluated with ECHO performed with a Sonos 5500 Philips equipment (12-MHz transducer) and RV obtained with an Orbiter-Siemens gamma camera using a pinhole collimator with a 4-mm aperture. Histopathological quantification of myocardial fibrosis was performed after euthanasia. Results: The control animals showed comparable results in the LVSF analysis obtained with ECHO and RV (83.5 ± 5% and 82.8 ± 2.8%, respectively, p > 0.05). The animals that received DXR presented lower LVSF values when compared with controls (p < 0.05); however, the LVSF values obtained by RV (60.6 ± 12.5%) were lower than those obtained by ECHO (71.8 ± 10.1%, p = 0.0004) in this group. An analysis of the correlation between the LVSF and myocardial fibrosis showed a moderate correlation when the LVSF was assessed by ECHO (r = -0.69, p = 0.0002) and a stronger correlation when it was assessed by RV (r = -0.79, p < 0.0001). On multiple regression analysis, only RV correlated independently with myocardial fibrosis. Conclusion: RV is an alternative method to assess the left ventricular function in small rodents in vivo. When compared with ECHO, RV showed a better correlation with the degree of myocardial injury in a model of DXR-induced cardiotoxicity.


Resumo Fundamento: A ventriculografia radioisotópica (VRI) é um método validado para avaliação da função sistólica do ventrículo esquerdo (FSVE) em pequenos roedores. Contudo, nenhum estudo prévio comparou os resultados obtidos com VRI com os obtidos por outros métodos de imagem neste contexto. Objetivos: Comparar os resultados de FSVE obtidos por VRI e por ecocardiografia (ECO) em modelo experimental de cardiotoxicidade por doxorrubicina (DXR) em ratos. Métodos: Ratos Wistar machos adultos controles (n = 7) e tratados com DXR (n = 22) em doses acumuladas de 8, 12 e 16 mg/kg, foram avaliados com ECO com equipamento Sonos 5500 Philips (transdutor de 12 MHz) e VRI adquirida em gama-câmara Orbiter-Siemens com colimador pinhole de 4 mm de abertura. Após eutanásia, foi realizada a quantificação histopatológica da fibrose miocárdica. Resultados: Os animais controles apresentaram valores comparáveis na análise da FSVE à ECO e à VRI (83,5 ± 5% e 82,8 ± 2,8%, respectivamente, p > 0,05). Os animais que receberam DXR apresentaram valores menores de FSVE quando comparados aos dos controles (p < 0,05); entretanto, observou-se neste grupo menores valores de FSVE obtidos por VRI (60,6 ± 12,5%) quando comparados aos obtidos pela ECO (71,8 ± 10,1%, p = 0,0004). A análise da correlação entre a FSVE e a fibrose miocárdica mostrou uma correlação moderada quando a FSVE foi estimada com a ECO (r = -0,69, p = 0,0002) e mais forte quando a FSVE foi obtida por VRI (r = -0,79, p < 0,0001). Apenas a VRI apresentou correlação de forma independente com a fibrose miocárdica à análise de regressão múltipla. Conclusão: A VRI é um método alternativo para avaliação da função ventricular esquerda in vivo em pequenos roedores, exibindo comparativamente à ECO melhor correlação com o grau de lesão miocárdica no modelo de cardiotoxicidade por DXR.

16.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 26(4): 240-5, out.-dez.2016.
Artigo em Português | LILACS | ID: biblio-831558

RESUMO

Apesar de a doença de Chagas ter sido intensamente estudada ao longo de mais de um século desde sua descoberta, existem lacunas de conhecimento com relação aos mecanismos fisiopatogênicos que levam ao desenvolvimento tardio da cardiomiopatia chagásica crônica. Um aspecto intrigante da doença é a complexa interação entre o hospedeiro e o parasita e suas repercussões. A ocorrência de documentada inflamação tecidual, presente mais intensamente na fase aguda, mas persistente em baixa intensidade também na fase crônica, pode ser consequência do tropismo cardíaco do parasita ou de alterações autoimunes. Nesta revisão, nós abordaremos as evidências do papel patológico da persistência do parasita e da autoimunidade na patogênese da doença de Chagas


Although Chagas disease has been studied intensely for more than a century since it was first discovered, there are gaps in the knowledge of the physiopathogenic mechanism that lead to the late development of chronic chagasic cardiomyopathy. An intriguing aspect of the disease is the complex interaction between the host and the parasite and its repercussions. The occurrence of documented tissue inflammation, which is more intensely present in the acute phase but also persists with lower intensity in the chronic phase, may be a consequence of cardiac tropism of the parasite or of autoimmune changes. In this review, we address the evidence of the pathological role of persistence of the parasite and autoimmunity in the pathogenesis of Chagas disease


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Cardiomiopatia Chagásica/patologia , Doença de Chagas/etiologia , Doença de Chagas/parasitologia , Trypanosoma cruzi/imunologia , Alopurinol/farmacologia , Ecocardiografia , Eletrocardiografia , Itraconazol/farmacologia , Radiografia
17.
J Am Heart Assoc ; 5(1)2016 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-26796255

RESUMO

BACKGROUND: Chronic Chagas cardiomyopathy in humans is characterized by segmental left ventricular wall motion abnormalities (WMA), mainly in the early stages of disease. This study aimed at investigating the detection of WMA and its correlation with the underlying histopathological changes in a chronic Chagas cardiomyopathy model in hamsters. METHODS AND RESULTS: Female Syrian hamsters (n=34) infected with 3.5×10(4) or 10(5) blood trypomastigote Trypanosoma cruzi (Y strain) forms and an uninfected control group (n=7) were investigated. After 6 or 10 months after the infection, the animals were submitted to in vivo evaluation of global and segmental left ventricular systolic function by echocardiography, followed by euthanasia and histological analysis for quantitative assessment of fibrosis and inflammation with tissue sampling in locations coinciding with the left ventricular wall segmentation employed at the in vivo echocardiographic evaluation. Ten of the 34 infected animals (29%) showed reduced left ventricular ejection fraction (<73%). Left ventricular ejection fraction was more negatively correlated with the intensity of inflammation (r=-0.63; P<0.0001) than with the extent of fibrosis (r=-0.36; P=0.036). Among the 24 animals with preserved left ventricular ejection fraction (82.9±5.5%), 8 (33%) showed segmental WMA predominating in the apical, inferior, and posterolateral segments. The segments exhibiting WMA, in comparison to those with normal wall motion, showed a greater extent of fibrosis (9.3±5.7% and 7±6.3%, P<0.0001) and an even greater intensity of inflammation (218.0±111.6 and 124.5±84.8 nuclei/mm², P<0.0001). CONCLUSIONS: Isolated WMA with preserved global systolic left ventricular function is frequently found in Syrian hamsters with experimental chronic Chagas cardiomyopathy whose underlying histopathological features are mainly inflammatory.


Assuntos
Cardiomiopatia Chagásica/patologia , Miocárdio/patologia , Disfunção Ventricular Esquerda/patologia , Função Ventricular Esquerda , Animais , Cardiomiopatia Chagásica/diagnóstico por imagem , Cardiomiopatia Chagásica/parasitologia , Cardiomiopatia Chagásica/fisiopatologia , Doença Crônica , Modelos Animais de Doenças , Ecocardiografia Doppler , Feminino , Fibrose , Mesocricetus , Volume Sistólico , Sístole , Fatores de Tempo , Trypanosoma cruzi/patogenicidade , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/parasitologia , Disfunção Ventricular Esquerda/fisiopatologia , Remodelação Ventricular
18.
Stem Cells Dev ; 24(18): 2181-92, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26059001

RESUMO

Heart failure induced by myocardial infarct (MI) attenuates the heart rate variability (HRV) and baroreflex sensitivity, which are important risk factors for life-threatening cardiovascular events. Therapies with mesenchymal stem cells (MSCs) have shown promising results after MI. However, the effects of MSCs on hemodynamic (heart rate and arterial pressure) variability and baroreflex sensitivity in chronic heart failure (CHF) following MI have not been evaluated thus far. Male Wistar rats received MSCs or saline solution intravenously 1 week after ligation of the left coronary artery. Control (noninfarcted) rats were also evaluated. MI size was assessed using single-photon emission computed tomography (SPECT). The left ventricular ejection fraction (LVEF) was evaluated using radionuclide ventriculography. Four weeks after MSC injection, the animals were anesthetized and instrumented for chronic ECG recording and catheters were implanted in the femoral artery to record arterial pressure. Arterial pressure and HRVs were determined in time and frequency domain (spectral analysis) while HRV was also examined using nonlinear methods: DFA (detrended fluctuation analysis) and sample entropy. The initial MI size was the same among all infarcted rats but was reduced by MSCs. CHF rats exhibited increased myocardial interstitial collagen and sample entropy combined with the attenuation of the following cardiocirculatory parameters: DFA indices, LVEF, baroreflex sensitivity, and HRV. Nevertheless, MSCs hampered all these alterations, except the LVEF reduction. Therefore, 4 weeks after MSC therapy was applied to CHF rats, MI size and myocardial interstitial fibrosis decreased, while baroreflex sensitivity and HRV improved.


Assuntos
Arritmias Cardíacas/terapia , Insuficiência Cardíaca/terapia , Frequência Cardíaca/fisiologia , Transplante de Células-Tronco Mesenquimais/métodos , Volume Sistólico/fisiologia , Animais , Arritmias Cardíacas/patologia , Pressão Arterial/fisiologia , Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca , Terapia Baseada em Transplante de Células e Tecidos/métodos , Vasos Coronários/cirurgia , Insuficiência Cardíaca/patologia , Hemodinâmica , Masculino , Células-Tronco Mesenquimais/citologia , Infarto do Miocárdio/patologia , Ventriculografia com Radionuclídeos , Ratos , Ratos Wistar , Função Ventricular Esquerda/fisiologia
19.
J Appl Physiol (1985) ; 118(10): 1276-85, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25792714

RESUMO

We investigated the effects of early ovarian hormone deprivation on the heart and the role of physical training in this condition using different approaches: cardiac autonomic tone, contractility, morphology and function, and cardiac fibrosis. Female Wistar rats (n = 48) were assigned into two groups: ovariectomized (Ovx; 10-wk-old) and control rats (Sham; 10-wk-old). Each group was further divided into two subgroups, sedentary and trained (aerobic training by swimming for 10 wk). The sedentary groups showed similar cardiac autonomic tone values; however, only the Sham group had an increase in vagal participation for the determination of the basal heart rate after physical training. The contractile responses to cardiac ß-agonists of the sedentary groups were similar, including an increased response to a ß1-agonist (dobutamine) observed after physical training. The Ovx sedentary group presented changes in cardiac morphology, which resulted in decreases in the ejection fraction, fractional shortening, and cardiac index compared with the Sham sedentary group. Physical training did little to alter these findings. Moreover, histology analysis showed a significant increase in cardiac fibrosis in the sedentary Ovx group, which was not observed in the trained Ovx group. We conclude that early ovarian hormone deprivation in rats impairs autonomic control, cardiac morphology, and cardiac function and increases cardiac fibrosis; however, it does not affect the contractility induced by dobutamine and salbutamol. Furthermore, this model of physical training prevented an increase in fibrosis and promoted an increase in the cardiac contractile response but had little effect on cardiac autonomic control or morphological and functional parameters.


Assuntos
Contração Miocárdica/fisiologia , Miocárdio/patologia , Ovariectomia , Condicionamento Físico Animal/fisiologia , Agonistas Adrenérgicos beta/farmacologia , Albuterol/farmacologia , Animais , Pressão Arterial/fisiologia , Sistema Nervoso Autônomo/fisiologia , Dobutamina/farmacologia , Ecocardiografia , Feminino , Fibrose , Frequência Cardíaca/fisiologia , Ratos , Ratos Wistar , Comportamento Sedentário , Volume Sistólico/efeitos dos fármacos , Natação/fisiologia
20.
J Nucl Cardiol ; 22(1): 130-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25080872

RESUMO

BACKGROUND: Primary microvascular angina (PMA) is a common clinical condition associated to negative impact on quality of life (QOL) and reduced physical capacity. This study aimed at evaluating the effects of aerobic physical training (APT) on myocardial perfusion, physical capacity, and QOL in patients with PMA. METHODS: We investigated 12 patients (53.8 ± 9.7 years old; 7 women) with PMA, characterized by angina, angiographycally normal coronary arteries, and reversible perfusion defects (RPDs) detected on (99m)Tc-sestamibi-SPECT myocardial perfusion scintigraphy (MPS). At baseline and after 4 month of APT, the patients underwent MPS, cardiopulmonary test, and QOL questionnaire. Stress-rest MPS images were visually analyzed by attributing semi-quantitative scores (0 = normal; 4 = absent uptake), using a 17-segment left ventricular model. Summed stress, rest, and difference scores (SDS) were calculated. RESULTS: In comparison to the baseline, in the post-training we observed a significant increase in peak-VO2 (19.4 ± 4.8 and 22.1 ± 6.2 mL·kg(-1)·minute(-1), respectively, P = .01), reduction of SDS (10.1 ± 8.8 and 2.8 ± 4.9, P = .008), and improvement in QOL scores. CONCLUSIONS: Physical training in patients with PMA is associated with reduction of myocardial perfusion abnormalities, increasing of physical capacity, and improvement in QOL. The findings of this hypothesis-generating study suggest that APT can be a valid therapeutic option for patients with PMA.


Assuntos
Angina Microvascular/diagnóstico por imagem , Angina Microvascular/psicologia , Imagem de Perfusão do Miocárdio , Idoso , Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Qualidade de Vida , Cintilografia , Compostos Radiofarmacêuticos , Inquéritos e Questionários , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único , Disfunção Ventricular Esquerda/diagnóstico por imagem
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