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1.
J Cardiol Cases ; 9(3): 121-123, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30534314

RESUMO

Anomalous origin of the left coronary artery from the pulmonary artery is rare but causes myocardial ischemia and sudden death. A few patients with this anomaly can survive to adulthood without sufficient collateral coronary flow or surgical intervention. We present here a case of acute inferior myocardial infarction, which may occur due to thrombotic occlusion of the right coronary artery, in a 63-year-old woman with anomalous origin of the left coronary artery from the pulmonary artery, providing specific coronary angiographic findings. .

3.
J Am Soc Echocardiogr ; 22(1): 63-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19131004

RESUMO

BACKGROUND: Using a novel speckle-tracking imaging method, time-left atrial (LA) volume curves (TLAVCs) can be automatically obtained. The aim of this study was to evaluate whether this method can be used for the measurement of LA function with TLAVCs. METHODS: In 10 normal subjects and 20 patients, apical 4-chamber images were obtained. Maximum volume, reservoir volume, conduit volume, booster pump volume, and minimum volume were measured from TLAVCs. The results were compared with those obtained by the manual tracing method on every frame during 1 cardiac cycle. RESULTS: There was good agreement between the speckle-tracking imaging and manual methods for maximum LA volume (r = 0.98, P < .001), reservoir volume (r = 0.82, P < .001), conduit volume (r = 0.87, P < .001), booster pump volume (r = 0.80, P < .001), and minimum volume (r = 0.98, P < .001). The time to obtain TLAVCs was significantly shorter with the speckle-tracking imaging method (64 +/- 22 seconds) than with the manual method (22 +/- 4 minutes). CONCLUSION: TLAVCs obtained using the speckle-tracking imaging method can be used for the rapid and noninvasive automated quantitation of LA function.


Assuntos
Algoritmos , Inteligência Artificial , Átrios do Coração/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Reconhecimento Automatizado de Padrão/métodos , Adulto , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia
4.
J Echocardiogr ; 7(1): 2-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27278073

RESUMO

BACKGROUND: Wall thickness in the distal part of the left anterior descending coronary artery (LAD) can be measured by using two-dimensional high-resolution transthoracic echocardiography (2DHTTE). The objective of this study was to compare the diagnostic accuracy of measuring carotid intima-media thickness (IMT) and distal LAD wall thickness for prediction of multivessel coronary artery disease (MVD). METHODS: We measured wall thickness in the distal LAD using 2DHTTE and carotid IMT using B-mode ultrasound in 100 patients who subsequently underwent coronary angiography (CAG). Patients were classified into three groups based on the results of CAG-no significant stenosis (group N), single-vessel disease (group S), or multivessel disease (group M). RESULTS: Successful measurements of LAD wall thickness were accomplished in 96 patients. Distal LAD wall thickness was significantly greater in group M (0.92 ± 0.20 mm) than in group N (0.72 ± 0.11 mm, P < 0.01) and group S (0.76 ± 0.19 mm, P < 0.01). Carotid IMT was significantly greater in group M (0.90 ± 0.24 mm) than in group N (0.75 ± 0.21 mm, P < 0.05) and group S (0.80 ± 0.17 mm, P < 0.05). Distal LAD wall thickness >0.8 mm had a sensitivity of 75% and a specificity of 67% in predicting MVD, whereas carotid IMT >0.8 mm was 63% sensitive and 67% specific in the prediction of MVD. There was a weak but significant correlation between distal LAD wall thickness and IMT (r = 0.31, P < 0.01). CONCLUSIONS: Non-invasive measurement of distal LAD wall thickness by 2DHTTE is feasible, and has equivalent diagnostic accuracy to IMT measurements for predicting MVD.

5.
J Cardiol ; 52(3): 276-84, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19027607

RESUMO

OBJECTIVES: Quantification of left ventricular (LV) mass has important prognostic implications. However, accurate measurement of LV mass has been difficult, in part because of the oblique angle at which the heart lies within the chest and the continuous movement of the heart itself. Multislice computed tomography (MSCT) allows assessment not only of coronary stenosis but LV volume, function, and mass. A novel three-dimensional (3D) region-growing-based semi-automated segmentation algorithm for measurements of LV mass, volume, and function was recently developed. This study evaluated this new 3D automated method for measurement of LV mass, by comparison with a well-established 2D manual contour-drawing algorithm. METHODS AND RESULTS: The study population consisted of 50 consecutive patients who underwent ECG-gated MSCT for evaluation of coronary arteries. The 3D algorithm for reliable segmentation was unsuccessful in two patients. In the remaining 48 patients, however, LV segmentation using this algorithm was performed and delivered visually reliable segmentation results. The 3D algorithm for analysis of LV function and mass is feasible based on volumetric data, and exhibits good correlation and agreement with the results obtained with the conventional 2D algorithm. The time required for the new automated algorithm was significantly shorter than that for the manual contour-drawing algorithm (P<0.0001) (automated algorithm: 468.0±205.1 s, manual algorithm: 1362.4±410.5 s, mean ±S.D.). CONCLUSIONS: The 3D semi-automated region-growing segmentation algorithm for analysis of LV function and mass is feasible based on volumetric data, and exhibits good correlations and agreement with the results of the conventional 2D manual contour-drawing algorithm.


Assuntos
Ventrículos do Coração/anatomia & histologia , Função Ventricular , Algoritmos , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Tamanho do Órgão , Tomografia Computadorizada por Raios X
7.
Am Heart J ; 153(6): 1080.e1-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17540213

RESUMO

BACKGROUND: Beta-blocker therapy reverses left ventricular (LV) remodeling in patients with idiopathic dilated cardiomyopathy (IDC). Improvement in coronary circulation by beta-blocker could play a role in these circumstances. This study investigated the relationship between change in coronary flow reserve (CFR), as a marker of coronary circulation, and subsequent improvement in LV ejection fraction (LVEF) at follow-up during carvedilol therapy in patients with IDC. METHODS: Eighteen patients with IDC underwent CFR measurements by transthoracic Doppler echocardiography at baseline and after 1 month of treatment with carvedilol. A follow-up echocardiographic assessment of LVEF was done at 12 +/- 6 months of treatment. The patients were classified by the degree of improvement in LVEF in the follow-up study, as group A (LVEF change > or = 10%) and group B (LVEF change < 10%). RESULTS: Although there was no significant difference in CFR between the 2 groups at baseline, CFR was significantly higher in group A than in group B at 1 month of therapy (3.7 +/- 0.5 vs 2.5 +/- 0.9; P < .01). Coronary flow reserve change after 1 month was significantly greater in group A than in group B (1.3 +/- 0.6 vs 0.4 +/- 0.5; P < .01). Logistic regression analysis revealed that CFR change predicted a significant improvement in LVEF at follow-up (P < .05). Furthermore, a significant correlation was found between the change in CFR after 1 month and that in LVEF on follow-up (r = 0.65, P < .01). CONCLUSIONS: This study demonstrated that early change in CFR is associated with subsequent improvement in LVEF, suggesting the potential predictive value of coronary circulation for subsequent LV reverse remodeling after beta-blocker therapy in patients with IDC.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Carbazóis/uso terapêutico , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/tratamento farmacológico , Reserva Fracionada de Fluxo Miocárdico/efeitos dos fármacos , Propanolaminas/uso terapêutico , Volume Sistólico/efeitos dos fármacos , Disfunção Ventricular Esquerda/prevenção & controle , Velocidade do Fluxo Sanguíneo , Cardiomiopatia Dilatada/diagnóstico por imagem , Carvedilol , Vasos Coronários/diagnóstico por imagem , Ecocardiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Disfunção Ventricular Esquerda/etiologia
8.
Am J Cardiol ; 98(11): 1531-7, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17126665

RESUMO

A novel 2-dimensional (2-D) echocardiographic tracking method enables the automated tracking of displacement between 2 points of interest in echocardiographic images. The purpose of this study was to evaluate whether this 2-D tracking method could be used to measure left ventricular (LV) wall thickness and percent systolic wall thickening (%WT) in parasternal short-axis views, in comparison with conventional manual measurement, and to determine whether this system can be used to quantitatively assess regional LV wall motion in echocardiography. In 24 subjects (12 with LV wall motion abnormalities), 6 segments in the short-axis images were assessed by this method. Two sample points at the endocardium and epicardium were tracked automatically during 1 cardiac cycle. Then, LV wall thickness and %WT were calculated. In 50 subjects (32 with LV wall motion abnormalities), average %WT as an average of all %WT in every degree of angle in each of the 6 segments was measured by this method, and the results were compared with the visual assessment of LV wall motion scores. There was excellent agreement between the 2-D tracking and manual methods for LV wall thickness (r = 0.99) and %WT (r = 0.97). The mean differences in LV wall thickness and %WT were 0.1 +/- 0.4 mm and 0 +/- 5.4%, respectively. Average %WT was significantly decreased in the regions of hypokinetic or akinetic wall motion compared with those of normal motion (18 +/- 4% and 4 +/- 4% vs 39 +/- 10%, p <0.001). In conclusion, this 2-D tracking method can be used for the noninvasive, automated quantitation of LV wall motion in 2-D echocardiography.


Assuntos
Ecocardiografia/métodos , Função Ventricular Esquerda/fisiologia , Humanos , Disfunção Ventricular Esquerda/fisiopatologia
9.
J Am Soc Echocardiogr ; 17(1): 21-7, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14712183

RESUMO

BACKGROUND: Although the measurement of coronary flow velocity (CFV) reserve (CFVR) in the left anterior descending coronary artery (LAD) by transthoracic Doppler echocardiography has been established, its success rate in the posterior descending coronary artery (PD) is still limited. OBJECTIVE: This study reports the feasibility and diagnostic accuracy of measuring CFVR in the PD by transthoracic Doppler echocardiography. METHODS: CFVR in both the distal LAD and the PD was measured in 151 consecutive patients before coronary angiography. PD flow was investigated under the guidance of a nondirectional Doppler color flow map with harmonic imaging in the modified apical 2-chamber view. Intravenous contrast agent, Levovist, was injected to enhance the CFV envelope at baseline and during hyperemia. RESULTS: CFVR was obtained in 145 patients in the LAD and 126 patients in the PD (P <.001). The success rate of CFVR measurement in the PD was significantly higher in the last 50 patients (88%) than it was in the first 50 patients (72%) (P <.05). CFVR in the PD was significantly lower for patients with significant stenosis of the artery supplying the PD than it was in those without stenosis (1.58 +/- 0.59 vs 2.45 +/- 0.72, P <.001). CFVR in the distal LAD was 1.40 +/- 0.62 in patients with significant LAD stenosis and 2.45 +/- 0.80 in those without stenosis (P <.001). If a cut-off value of CFVR < 2 was used, sensitivity, specificity, and accuracy for the diagnosis of significant (>50%) stenosis of the artery supplying the PD were 84%, 83%, and 83%, respectively, whereas for the LAD they were 91%, 75%, and 80%, respectively. CONCLUSIONS: Noninvasive measurement of CFVR in the PD could be obtained in the majority of unselected patients using a nondirectional Doppler color flow map and contrast-enhanced harmonic imaging. The diagnostic accuracy of CFVR in the PD is similar to that of the LAD and, hence, has a potential clinical use.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Circulação Coronária/fisiologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/fisiopatologia , Ecocardiografia , Aumento da Imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/fisiologia , Angiografia Coronária , Estenose Coronária/diagnóstico , Estenose Coronária/epidemiologia , Estenose Coronária/fisiopatologia , Diástole/fisiologia , Ecocardiografia Doppler , Estudos de Viabilidade , Feminino , Frequência Cardíaca/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Sístole/fisiologia
10.
Free Radic Res ; 36(10): 1079-84, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12516879

RESUMO

We investigated whether free Fe ions were released in erythrocytes during aging process in the circulation. Young and senescent erythrocytes were separated from freshly drawn human blood by Percoll density gradient centrifugation. Two different methods were employed for determination of free Fe ions in erythrocytes, desferrioxamine (DFO) method and bleomycin method. DFO-chelatable Fe ions were detected in whole erythrocytes from 2 donors, and the DFO-chelatable free Fe ion levels in senescent erythrocytes were higher than those in young erythrocytes. Bleomycin-sensitive Fe ions, which was rather lower than DFO-chelatable Fe ions, were also detected in whole erythrocytes from 5 donors, and the free Fe ion levels in senescent erythrocytes were also higher than those in young erythrocytes. Free Fe ions may be derived from oxidative damage of hemoglobin, because treatment of whole erythrocytes or purified oxyhemoglobin with hydrogen peroxide gave increased free Fe ions. The results indicated that free Fe ions were released from erythrocytes during aging process in the circulation. Released free Fe ions would promote oxidative damages of the cells during aging process.


Assuntos
Envelhecimento Eritrocítico , Eritrócitos/química , Ferro/sangue , Bleomicina/química , Separação Celular , Centrifugação com Gradiente de Concentração , Cromatografia Líquida de Alta Pressão , Desferroxamina/química , Compostos Ferrosos/sangue , Hemoglobinas/química , Humanos , Peróxido de Hidrogênio/farmacologia , Ferro/química , Quelantes de Ferro/química , Oxirredução , Estresse Oxidativo , Soluções , Substâncias Reativas com Ácido Tiobarbitúrico/análise
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