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1.
Braz. j. med. biol. res ; 40(11): 1557-1565, Nov. 2007. graf, tab
Artigo em Inglês | LILACS | ID: lil-464316

RESUMO

The severity of left ventricular (LV) dysfunction in rats with myocardial infarction (MI) varies widely. Because homogeneity in baseline parameters is essential for experimental investigations, a study was conducted to establish whether Doppler echocardiography (DE) could accurately identify animals with high LV end-diastolic pressure as a marker of LV dysfunction soon after MI. Direct measurements of LV end-diastolic pressure were made and DE was performed simultaneously 1 week after surgically induced MI (N = 16) or sham-operation (N = 17) in female Wistar rats (200 to 250 g). The ratio of peak early (E) to late (A) diastolic LV filling velocities and the ratio of E velocity to peak early (Em) diastolic myocardial velocity were the best predictors of high LV end-diastolic pressure (>12 mmHg) soon after MI. Cut-off values of 1.77 for the E/A ratio (P = 0.001) identified rats with elevated LV end-diastolic pressure with 90 percent sensitivity and 80 percent specificity. Cut-off values of 20.4 for the E/Em ratio (P = 0.0001) identified rats with elevated LV end-diastolic pressure with 81.8 percent sensitivity and 80 percent specificity. Moreover, E/A and E/Em ratios were the only echocardiographic parameters independently associated with LV end-diastolic pressure in multiple linear regression analysis. Therefore, DE identifies rats with high LV end-diastolic pressure soon after MI. These findings have implications for using serial DE in animal selection and in the assessment of their response to experimental therapies.


Assuntos
Animais , Feminino , Ratos , Hemodinâmica/fisiologia , Infarto do Miocárdio/fisiopatologia , Disfunção Ventricular Esquerda , Modelos Animais de Doenças , Ecocardiografia Doppler , Infarto do Miocárdio/complicações , Infarto do Miocárdio , Ratos Wistar , Reprodutibilidade dos Testes , Disfunção Ventricular Esquerda/etiologia
2.
Braz J Med Biol Res ; 40(11): 1557-65, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17934652

RESUMO

The severity of left ventricular (LV) dysfunction in rats with myocardial infarction (MI) varies widely. Because homogeneity in baseline parameters is essential for experimental investigations, a study was conducted to establish whether Doppler echocardiography (DE) could accurately identify animals with high LV end-diastolic pressure as a marker of LV dysfunction soon after MI. Direct measurements of LV end-diastolic pressure were made and DE was performed simultaneously 1 week after surgically induced MI (N = 16) or sham-operation (N = 17) in female Wistar rats (200 to 250 g). The ratio of peak early (E) to late (A) diastolic LV filling velocities and the ratio of E velocity to peak early (Em) diastolic myocardial velocity were the best predictors of high LV end-diastolic pressure (>12 mmHg) soon after MI. Cut-off values of 1.77 for the E/A ratio (P = 0.001) identified rats with elevated LV end-diastolic pressure with 90% sensitivity and 80% specificity. Cut-off values of 20.4 for the E/Em ratio (P = 0.0001) identified rats with elevated LV end-diastolic pressure with 81.8% sensitivity and 80% specificity. Moreover, E/A and E/Em ratios were the only echocardiographic parameters independently associated with LV end-diastolic pressure in multiple linear regression analysis. Therefore, DE identifies rats with high LV end-diastolic pressure soon after MI. These findings have implications for using serial DE in animal selection and in the assessment of their response to experimental therapies.


Assuntos
Hemodinâmica/fisiologia , Infarto do Miocárdio/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Animais , Modelos Animais de Doenças , Ecocardiografia Doppler , Feminino , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico por imagem , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Disfunção Ventricular Esquerda/etiologia
3.
Braz J Med Biol Res ; 39(5): 687-95, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16648907

RESUMO

Although echocardiography has been used in rats, few studies have determined its efficacy for estimating myocardial infarct size. Our objective was to estimate the myocardial infarct size, and to evaluate anatomic and functional variables of the left ventricle. Myocardial infarction was produced in 43 female Wistar rats by ligature of the left coronary artery. Echocardiography was performed 5 weeks later to measure left ventricular diameter and transverse area (mean of 3 transverse planes), infarct size (percentage of the arc with infarct on 3 transverse planes), systolic function by the change in fractional area, and diastolic function by mitral inflow parameters. The histologic measurement of myocardial infarction size was similar to the echocardiographic method. Myocardial infarct size ranged from 4.8 to 66.6% when determined by histology and from 5 to 69.8% when determined by echocardiography, with good correlation (r = 0.88; P < 0.05; Pearson correlation coefficient). Left ventricular diameter and mean diastolic transverse area correlated with myocardial infarct size by histology (r = 0.57 and r = 0.78; P < 0.0005). The fractional area change ranged from 28.5 +/- 5.6 (large-size myocardial infarction) to 53.1 +/- 1.5% (control) and correlated with myocardial infarct size by echocardiography (r = -0.87; P < 0.00001) and histology (r = -0.78; P < 00001). The E/A wave ratio of mitral inflow velocity for animals with large-size myocardial infarction (5.6 +/- 2.7) was significantly higher than for all others (control: 1.9 +/- 0.1; small-size myocardial infarction: 1.9 +/- 0.4; moderate-size myocardial infarction: 2.8 +/- 2.3). There was good agreement between echocardiographic and histologic estimates of myocardial infarct size in rats.


Assuntos
Ecocardiografia Doppler , Contração Miocárdica/fisiologia , Infarto do Miocárdio/diagnóstico por imagem , Função Ventricular Esquerda/fisiologia , Remodelação Ventricular/fisiologia , Animais , Modelos Animais de Doenças , Feminino , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Ratos , Ratos Wistar , Índice de Gravidade de Doença
4.
Braz. j. med. biol. res ; 39(5): 687-695, May 2006. tab, graf
Artigo em Inglês | LILACS | ID: lil-425783

RESUMO

Although echocardiography has been used in rats, few studies have determined its efficacy for estimating myocardial infarct size. Our objective was to estimate the myocardial infarct size, and to evaluate anatomic and functional variables of the left ventricle. Myocardial infarction was produced in 43 female Wistar rats by ligature of the left coronary artery. Echocardiography was performed 5 weeks later to measure left ventricular diameter and transverse area (mean of 3 transverse planes), infarct size (percentage of the arc with infarct on 3 transverse planes), systolic function by the change in fractional area, and diastolic function by mitral inflow parameters. The histologic measurement of myocardial infarction size was similar to the echocardiographic method. Myocardial infarct size ranged from 4.8 to 66.6 percent when determined by histology and from 5 to 69.8 percent when determined by echocardiography, with good correlation (r = 0.88; P < 0.05; Pearson correlation coefficient). Left ventricular diameter and mean diastolic transverse area correlated with myocardial infarct size by histology (r = 0.57 and r = 0.78; P < 0.0005). The fractional area change ranged from 28.5 ± 5.6 (large-size myocardial infarction) to 53.1 ± 1.5 percent (control) and correlated with myocardial infarct size by echocardiography (r = -0.87; P < 0.00001) and histology (r = -0.78; P < 00001). The E/A wave ratio of mitral inflow velocity for animals with large-size myocardial infarction (5.6 ± 2.7) was significantly higher than for all others (control: 1.9 ± 0.1; small-size myocardial infarction: 1.9 ± 0.4; moderate-size myocardial infarction: 2.8 ± 2.3). There was good agreement between echocardiographic and histologic estimates of myocardial infarct size in rats.


Assuntos
Animais , Feminino , Ratos , Ecocardiografia Doppler , Contração Miocárdica/fisiologia , Infarto do Miocárdio , Função Ventricular Esquerda/fisiologia , Remodelação Ventricular/fisiologia , Modelos Animais de Doenças , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Ratos Wistar , Índice de Gravidade de Doença
5.
Arq Bras Cardiol ; 76(5): 355-68, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11359184

RESUMO

PURPOSE: To evaluate 2 left ventricular mass index (LVMI) normality criteria for the prevalence of left ventricular geometric patterns in a hypertensive population ( HT ). METHODS: 544 essential hypertensive patients, were evaluated by echocardiography, and different left ventricular hypertrophy criteria were applied: 1 - classic : men - 134 g/m2 and women - 110 g/m2; 2- obtained from the 95th percentil of LVMI from a normotensive population (NT). RESULTS: The prevalence of 4 left ventricular geometric patterns, respectively for criteria 1 and 2, were: normal geometry - 47.7% and 39.3%; concentric remodelying - 25.4% and 14.3%; concentric hypertrophy - 18.4% and 27.7% and excentric hypertrophy - 8.8% and 16.7%, which confered abnormal geometry to 52.6% and 60.7% of hypertensive. The comparative analysis between NT and normal geometry hypertensive group according to criteria 1, detected significative stuctural differences,"( *p < 0.05):LVMI- 78.4 +/- 1.50 vs 85.9 +/-0.95 g/m2 *; posterior wall thickness -8.5 +/- 0.1 vs 8.9 +/- 0.05 mm*; left atrium - 33.3 +/- 0.41 vs 34.7 +/- 0.30 mm *. With criteria 2, significative structural differences between the 2 groups were not observed. CONCLUSION: The use of a reference population based criteria, increased the abnormal left ventricular geometry prevalence in hypertensive patients and seemed more appropriate for left ventricular hypertrophy detection and risk stratification.


Assuntos
Hipertensão/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Análise de Variância , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Ecocardiografia Doppler , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Humanos , Masculino , Seleção de Pacientes , Estudos Retrospectivos , Medição de Risco
6.
Arq Bras Cardiol ; 75(2): 125-36, 2000 Aug.
Artigo em Inglês, Português | MEDLINE | ID: mdl-10983029

RESUMO

OBJECTIVE: To assess by Doppler echocardiography the structural and functional alterations of rat heart with surgical induced extensive myocardial infarction. METHODS: Five weeks after surgical ligature of the left coronary artery, 38 Wistar-EPM rats of both sexes, 10 of them with extensive infarction, undergone anatomical and functional evaluation by Doppler echocardiography and then euthanized for anatomopathological analysis. RESULTS: Echocardiography was 100% sensible and specific to anatomopathological confirmed extensive miocardial infarction. Extensive infarction lead to dilatation of left ventricle (diastolic diameter: 0.89 cm vs.0.64 cm; systolic: 0. 72 cm vs. 0.33 cm) and left atrium (0.55 cm vs. 0.33 cm); thinning of left ventricular anterior wall (systolic: 0.14 cm vs. 0.23 cm, diastolic: 0.11 cm vs. 0.14 cm); increased mitral E/ A wave relation (6.45 vs. 1.95). Signals of increased end diastolic ventricle pressure, B point in mitral valve tracing in 62.5% and signs of pulmonary hypertension straightening of pulmonary valve (90%) and notching of pulmonary systolic flow (60%) were observed in animals with extensive infarction. CONCLUSION: Doppler echocardiography has a high sensitivity and specificity for detection of chronic extensive infarction. Extensive infarction caused dilatation of left cardiac chambers and showed in Doppler signals of increased end diastolic left ventricular pressure and pulmonary artery pressure.


Assuntos
Ecocardiografia Doppler , Coração/anatomia & histologia , Coração/fisiologia , Infarto do Miocárdio/diagnóstico por imagem , Miocárdio/patologia , Doenças dos Animais , Animais , Feminino , Ventrículos do Coração/diagnóstico por imagem , Masculino , Infarto do Miocárdio/patologia , Tamanho do Órgão , Ratos , Ratos Wistar , Valores de Referência , Sensibilidade e Especificidade , Disfunção Ventricular Esquerda/diagnóstico por imagem
7.
Arq Bras Cardiol ; 75(2): 137-44, 2000 Aug.
Artigo em Inglês, Português | MEDLINE | ID: mdl-10983030

RESUMO

Multiple arterial anomalies characterized by tortuosity and rolling of the pulmonary arteries and aorta were diagnosed on echocardiography in an asymptomatic newborn infant with a phenotype suggesting Ehlers-Danlos syndrome. These changes were later confirmed on angiography, which also showed peripheral vascular abnormalities. The electrocardiogram showed a probable hemiblock of the left anterosuperior branch, and the chest x-ray showed an excavated pulmonary trunk with normal pulmonary flow.


Assuntos
Anormalidades Múltiplas/diagnóstico por imagem , Aorta Torácica/anormalidades , Síndrome de Ehlers-Danlos/diagnóstico por imagem , Artéria Pulmonar/anormalidades , Angiografia , Aorta Abdominal/anormalidades , Aorta Abdominal/diagnóstico por imagem , Aorta Torácica/diagnóstico por imagem , Seguimentos , Humanos , Recém-Nascido , Masculino , Artéria Pulmonar/diagnóstico por imagem , Ultrassonografia
8.
Arq Bras Cardiol ; 74(3): 243-52, 2000 Mar.
Artigo em Inglês, Português | MEDLINE | ID: mdl-10951827

RESUMO

We report here a case of coronary artery fistula in a neonate with clinical signs of heart failure. The electrocardiogram showed signs of left ventricular hypertrophy and diffuse alterations in ventricular repolarization. Chest X-ray showed an enlargement of the cardiac silhouette with an increase in pulmonary flow. After echocardiographic diagnosis and angiographic confirmation, closure of the fistulous trajectory was performed with a detachable balloon with an early and late successful outcome.


Assuntos
Fístula Artério-Arterial/complicações , Anomalias dos Vasos Coronários/complicações , Insuficiência Cardíaca/etiologia , Fístula Artério-Arterial/diagnóstico , Fístula Artério-Arterial/terapia , Cateterismo/métodos , Angiografia Coronária , Anomalias dos Vasos Coronários/diagnóstico , Anomalias dos Vasos Coronários/terapia , Ecocardiografia Doppler , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Humanos , Lactente , Masculino
9.
Arq Bras Cardiol ; 74(5): 447-52, 2000 May.
Artigo em Inglês, Português | MEDLINE | ID: mdl-10951836

RESUMO

A rare association of pulmonary atresia with an intact septum was diagnosed through echocardiography in a fetus 32 weeks of gestational age. The diagnosis was later confirmed by echocardiography of the newborn infant and further on autopsy. The aortic valve was bicuspid with a pressure gradient of 81 mmHg, and the right ventricle was hypoplastic, as were the pulmonary trunk and arteries, and the blood flow was totally dependent on the ductus arteriosus.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Septos Cardíacos/diagnóstico por imagem , Atresia Pulmonar/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/congênito , Evolução Fatal , Feminino , Septos Cardíacos/embriologia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Hipertrofia Ventricular Esquerda/congênito , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Recém-Nascido , Gravidez , Atresia Pulmonar/complicações
10.
Clin Cardiol ; 23(5): 371-5, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10803447

RESUMO

BACKGROUND: Diabetic cardiomyopathy is a well-defined complication of diabetes that occurs in the absence of ischemic, vascular, and hypertensive disease. HYPOTHESIS: The study was undertaken to test the relationship among autonomic neuropathy (AN), 24-h blood pressure (BP) profile, and left ventricular function. METHODS: Nineteen type-1 diabetic patients underwent autonomic tests and echocardiographic examination. Patients were divided according to the presence (AN+) or absence (AN-) of AN. RESULTS: In the AN+ group (n = 8), the E/A ratio at echo was lower than in the AN- group (n = 11) (1.1 +/- 0.3 vs. 1.6 +/- 0.3; p < 0.005). Systolic and diastolic BP reductions during sleep were smaller in the AN+ than in the AN- group (6.6 +/- 6.6 vs. 13.0 +/- 4.3%; p < 0.03 for systolic and 12.8 +/- 6.8 vs. 20.0 +/- 4.0% for diastolic BP reduction; p < 0.03, respectively). Considering all patients, the E/A ratio correlated inversely with awake diastolic BP (r - 0.63; p = 0.005); sleep systolic BP (r - 0.48; p = 0.04), and sleep diastolic BP (r - 0.67; p = 0.002). The AN correlated with diastolic interventricular septum thickness (r 0.57; p = 0.01), sleep systolic BP (r 0.45; p = 0.05), sleep diastolic BP (r 0.54; p = 0.02), and correlated inversely with systolic and diastolic sleep BP reduction (r - 0.49; p = 0.03 and r - 0.67; p = 0.002, respectively). Finally, E/A ratio and AN score correlated between themselves (r - 0.6; p = 0.005). CONCLUSION: Our results suggest that left ventricular diastolic dysfunction may be detected very early in type-1 diabetic patients with AN. Parasympathetic lesion and nocturnal elevations in BP could be the link between AN and diastolic ventricular dysfunction.


Assuntos
Doenças do Sistema Nervoso Autônomo/complicações , Diabetes Mellitus Tipo 1/complicações , Neuropatias Diabéticas/complicações , Neuropatias Diabéticas/diagnóstico , Coração/inervação , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/etiologia , Adulto , Análise de Variância , Doenças do Sistema Nervoso Autônomo/diagnóstico , Determinação da Pressão Arterial , Diabetes Mellitus Tipo 1/diagnóstico , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Probabilidade , Prognóstico , Índice de Gravidade de Doença , Estatísticas não Paramétricas
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