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991.
Background: We assessed the hypothesis that diastolic function represented by left atrial size determines the rate of development of symptoms and the risk of all‐cause mortality in asymptomatic patients with severe aortic stenosis (AS). Methods: From a database of 622 asymptomatic patients with isolated severe AS (velocity by Doppler ≥ 4 m/sec) followed for 5.4 ± 4 years, we reviewed the echocardiograms and evaluated Doppler echocardiographic indices of diastolic function. Prediction of symptom development and mortality by left atrial diameter with and without adjusting for clinical and echocardiographic parameters was performed using Cox proportional‐hazards regression analysis. Results: The age was 71 ± 11 years and 317 (62%) patients were males. The aortic valve mean gradient was 46 ± 11 mmHg, and the Doppler‐derived aortic valve area was 0.9 ± 0.2 cm2. During follow‐up, symptoms developed in 233 (45%), valve surgery was performed in 290 (57%) and 138 (27%) died. Left atrial enlargement was significantly correlated with symptom development (P < 0.05) but the association diminished after adjusting for aortic valve area and peak velocity (P = 0.2). However, atrial diameter predicted death independent of age and gender (P = 0.007), comorbid conditions (P = 0.03), and AS severity and Doppler parameters of diastolic function (P = 0.002). Conclusion: Diastolic function, represented as left atrial diameter, is related to mortality in asymptomatic patients with severe AS. (ECHOCARDIOGRAPHY 2010;27:105‐109)  相似文献   
992.
Objective: Coronary flow velocity reserve (CFR) by pulsed Doppler echocardiography is a useful hemodynamic index to evaluate the coronary microcirculatory dysfunction in the left anterior descending coronary artery (LAD). The present study was designed to evaluate the long‐term predictive value of CFR for mortality in patients with right (RC) and/or left circumflex coronary artery (CX) stenosis without epicardial LAD disease. Methods: A total of 49 patients with significant RC and/or CX stenosis were enrolled in this prospective follow‐up study. All patients had undergone coronary angiography demonstrating significant RC and/or CX stenosis without LAD disease and dipyridamole stress transoesophageal echocardiography as CFR measurement. Results: The success rate of follow‐up was 43 out of 49 (88%). During a mean follow‐up of 97 ± 29 months, 14 patients suffered cardiovascular deaths (12 sudden cardiac deaths and 2 strokes), and 1 patient died of pulmonal tumor. Patients who died during the follow‐up had significantly lower CFR values (1.85 ± 0.43 vs. 2.31 ± 0.57, P < 0.05). Using ROC analysis, CFR <2.09 had the highest accuracy in predicting cardiovascular survival (sensitivity 80%, specificity 57%, area under the curve 73%, P = 0.003). The logistic regression model identified only CFR as an independent predictor of survival (hazard ratio [HR] 6.26, 95% CI of HR 1.23–19.61, P = 0.024). Conclusions: Long‐term prognostic significance of CFR for the prediction of mortality has been demonstrated during a 9‐year follow‐up in patients with significant coronary artery disease not involving the LAD. (Echocardiography 2010;27:306‐310)  相似文献   
993.
Background: Although the residual lesions after surgical correction of tetralogy of Fallot (TOF) can be evaluated by Doppler echocardiography (DE), the relation of DE parameters with the proBNP level, a potential biomarker of right ventricle overload, is not well known. The objective of this study was to evaluate the DE parameters and their relation to proBNP levels. Methods: proBNP plasma level and Doppler echocardiography parameters were obtained on the same day in 49 patients later after repair of TOF (mean age of 14.7 years, 51% female, mean PO time of 9.5 years). The DE parameters studied were the dimensions of the right atrium (RA) and ventricle (RV), RV diastolic and systolic function, and residual pulmonary lesions. The relation between them and proBNP levels were analyzed and the cutoff values of DE parameters for elevated proBNP determined. Results: proBNP was elevated in 53% and correlated with RV diastolic diameter (r = 0.41; P = 0.003), RA longitudinal (r = 0.52; P = 0.0001) and transversal (r = 0.47; P = 0.001) diameters, pressure half time of pulmonary regurgitation (PR) velocity (PHT) (r =?0.42; P = 0.005), and the PR index (r =?0.60; P < 0.001). By multivariate analysis, the PR index (r =?597; P = 0,001; CI: ?913.2 to ?280.8) and RA longitudinal (r = 7.74; P < 0,001; CI 4.18 to 11.31) were independent predictors of elevated proBNP. PHT lower than 64 msec (0.76) and PRi lower than 0.65 (0.81) had the best accuracy for elevated proBNP. Conclusion: proBNP may be increased in patients after surgical repair of TOF, correlated with the size of right cardiac chambers and the severity of PR. (Echocardiography 2010;27:442‐447)  相似文献   
994.
心脏移植是终末期心力衰竭患者的有效治疗方法。超声心动图检查能为心脏的结构与功能提供全面的信息,是评估心脏移植术的主要无创方法。现就超声心动图对心脏移植术的作用做一综述。  相似文献   
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We describe the value of live/real time three‐dimensional transthoracic echocardiography (3DTTE) over two‐dimensional transthoracic echocardiography (2DTTE) in the assessment of inferior vena cava (IVC) and hepatic vein (HV) obstruction in a patient with sickle cell disease. 3DTTE provided additional information when compared to 2DTTE by (1) identifying the obstructing lesion as a likely thrombus, (2) by providing assessment of anatomical severity of IVC lumen obstruction since the thrombus could be visualized en face also, and (3) identifying an area of increased mobility of a portion of the thrombus suggesting greater risk of embolization. (Echocardiography 2010;27:594‐596)  相似文献   
997.
Aim: The purpose of this study is to assess the ability of resting echocardiography to detect an acute coronary syndrome (ACS) before the occurrence of ischemic electrocardiogram (ECG) changes or troponin‐T elevations. Methods: Four hundred and three patients who presented to the emergency room (ER) with chest pain, normal ECGs, and normal troponin‐T levels were admitted to the cardiologist‐run Chest Pain Unit (CPU) for further monitoring. They underwent serial resting echocardiography for monitoring of left ventricle wall motion (LVWM), ECG telemetry monitoring, and serial troponin‐T measurements. Results: An ACS was detected in 49 patients (12.1%). These 49 patients were then subdivided into three different groups based on the initial mode of detection of their ACS. In group A, 16 of 49 (32.6%) patients had ACS shown by echocardiographic detection of LVWM abnormalities. In group B, 24 of 49 (48.9%) patients had an ACS detected by ischemic ECG changes. In group C, 9 of 49 (18.3%) patients had an ACS detected by troponin‐T elevations. The shortest time interval between CPU‐admission and ACS‐detection occurred in group A (A vs. B, P < 0.003; A vs. C, P < 0.0001). In group A, cardiac angiogram showed that the culprit coronary lesion was more frequent in the circumflex artery (11 out of 16; 68.7%) (LCx vs. LAD, P < 0.02; LCx vs. RCA, P < 0.001) and of these 11 patients with circumflex lesions, the ECG was normal in eight (72.7%) patients. Conclusion: This study demonstrates the utility of LVWM monitoring by serial echocardiography as part of a diagnostic protocol that can be implemented in a CPU. Furthermore, echocardiography could become an essential tool used in the diagnosis of ACS secondary to circumflex lesions. (Echocardiography 2010;27:597‐602)  相似文献   
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