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991.
Tamin SS Dillon J Aizan K Kadiman S Latiff HA 《Echocardiography (Mount Kisco, N.Y.)》2012,29(2):E34-E38
This case report describes a 20-year-old woman with Turner's syndrome who presented with reduced effort tolerance limited by dyspnea. She had previously been on pediatric cardiology follow-up for congenital subvalvular aortic stenosis first diagnosed at age 7. Unfortunately she defaulted after two visits before any intervention could be done. Transthoracic echocardiography demonstrated severe aortic incompetence (AI) with a membrane-like structure in the left ventricular outflow tract (LVOT). The mean pressure gradient across the LVOT on continuous wave Doppler was 41 mmHg. The membranous interventricular septum appeared aneurysmal and it was observed that the "subaortic membrane" had a connection to the anterolateral papillary muscle via a strand of chordal tissue. Further images were captured using two-dimensional and three-dimensional transthoracic and transesophageal echocardiography (iE33, Philips Medical Systems, Andover, MA, USA). After a review of the literature it was concluded that this appeared to be an accessory mitral valve (AMV) leaflet causing LVOT obstruction associated with AI. AMV tissue is a rare congenital malformation causing LVOT obstruction. Because it is so unusual, it may not be immediately recognizable even in a high volume echocardiography laboratory. The clue which helped with the diagnosis was the strand of chordal tissue which connected the mass to the papillary muscle. This anomaly is often associated with LVOT obstruction. 相似文献
992.
Elsherbiny IA 《Echocardiography (Mount Kisco, N.Y.)》2012,29(2):158-164
Background: Endothelial and microvascular dysfunction have been implicated in slow coronary flow (SCF). How and to what extent do these etiological factors affect left ventricular (LV) function and exercise capacity? Aim: The aim of the study was to evaluate LV systolic and diastolic function by pulsed tissue Doppler imaging (TDI) in SCF patients and their effects on exercise capacity. Subjects and methods: Sixty SCF patients and 20 control subjects were included in the study. Echocardiographic examination, treadmill exercise test, and TDI were performed. Isovolumic myocardial acceleration (IVA) and myocardial performance index (MPI) were measured. Results: TDI mean parameters for systolic and diastolic LV function were significantly impaired in SCF group with decreased Sa, IVA, Ea/Aa, and increased MPI (0.31 ± 0.06 vs. 0.26 ± 0.04, P < 0.01) compared to control. There was significant correlation between thrombolysis in myocardial infarction (TIMI) frame count and TDI mean parameters for LV systolic function (Sa & IVA, r =?0.53, P < 0.01 & r =?0.36, P < 0.05, respectively). Mean TIMI frame count was correlated with MPI and E/Ea. SCF patients had poorer peak exercise capacity than the controls (9.9 ± 1.9 METs vs. 12.7 ± 2.3, P < 0.01) with significant negative correlation with mean TIMI frame count (r =?0.46, P < 0.01). Conclusion: There is impairment of LV systolic and diastolic function in SCF patients with clinical impact on exercise capacity which emphasizes the importance of close follow‐up of these patients for risk stratification. (Echocardiography 2012;29:158‐164) 相似文献
993.
994.
JA Urbano-Moral AR Patel MS Maron JA Arias-Godinez NG Pandian 《Echocardiography (Mount Kisco, N.Y.)》2012,29(8):997-1010
Speckle-tracking echocardiography (STE) is an advanced echocardiographic technique that allows a novel approach to the assessment of cardiac physiology through the study of myocardial mechanics. In its three-dimensional (3D) modality, it overcomes the drawbacks inherent to other echocardiographic techniques, namely two-dimensional echocardiography and tissue Doppler imaging. Several research studies and software improvements have led 3D-STE to become a promising tool for accurate evaluation of global and regional cardiac function. This article addresses the image acquisition, analytical methods, and parameters of myocardial mechanics that could be derived from 3D-STE. This systematic guidance may help to establish its usefulness in the global and regional evaluation of cardiac function, and to facilitate its clinical application. 相似文献
995.
Yang ZR Zhou QC Lee L Zou L Zeng S Tan Y Cao DM 《Echocardiography (Mount Kisco, N.Y.)》2012,29(3):340-345
Objective: To assess the left ventricular (LV) longitudinal systolic function and asynchrony in patients with coronary atherosclerotic heart disease (CAD) by syngo velocity vector imaging (VVI). Methods: Twenty‐eight control subjects and 79 patients with CAD were examined, including 28 patients with myocardial infarction, 26 patients with coronary lumen stenosis <50%, and 25 patients with myocardial ischemia. According to the results of coronary arteriography and electrocardiogram (ECG), the myocardial segments of the LV of CAD patients were divided into four groups: ischemic, infarcted, nonischemic, and normal. Dynamic imaging was performed on all subjects. The systolic peak strain (Smax), systolic strain rate (SRmax), time to peak strain (PTs), and time to peak strain rate (PTsr) in every cardiac cycle were measured. Results: A total of 1,253 out of 1,712 (96.5%) segments were successfully analyzed with VVI. Smax and SRmax of the ischemic and infarcted segments were impaired in CAD patients. Optimal sensitivity and specificity were obtained with strain and strain rate cutoffs of ?14.08% and ?0.83 s?1, respectively, for detecting ischemic segments and ?6.65% and ?0.38 s?1, respectively, for detecting infarcted segments. The PTs and PTsr were significantly longer in the ischemic and infarcted segments compared to those of the control group. Conclusions: Utilizing VVI, the longitudinal strain, strain rate, and peak time in CAD patients are easy to obtain and reproducible. Strain and strain rate cutoff values of abnormal myocardium are valuable for detecting ischemia and infarction. The PTs and PTsr values possibly estimate myocardium asynchrony in CAD patients. (Echocardiography 2012;29:340‐345) 相似文献
996.
997.
Sebastian J. Buss Mostafa Emami Derliz Mereles Grigorios Korosoglou Arnt V. Kristen Andreas Voss Dieter Schellberg Christian Zugck Christian Galuschky Evangelos Giannitsis Ute Hegenbart Anthony D. Ho Hugo A. Katus Stefan O. Schonland Stefan E. Hardt 《Journal of the American College of Cardiology》2012
998.
Ranganathan A Ganesan G Sangareddi V Pillai AP Ramasamy A 《Echocardiography (Mount Kisco, N.Y.)》2012,29(7):E169-E172
Isolated noncompaction of ventricular myocardium (INVM) is a genetic cardiomyopathy due to abnormal arrest in endomyocardial embryogenesis between fetal 5th and 8th week. Noncompaction of right ventricle alone is rare. Here we present one such case where a young man presented with progressive right heart failure and atrial fibrillation. Subsequent evaluation by echo and cardiac magnetic resonance imaging confirmed our diagnosis. The cardinal manifestations of INVM are heart failure, arrhythmia, and embolic events and our case presented with former two manifestations. Echocardiographic criteria for diagnosing INVM are discussed. 相似文献
999.
Magical ideation has repeatedly been shown to be related to handedness, with mixed-handers exhibiting higher levels of magical thinking. However, most previous research has assessed hand preference with a questionnaire measure, leaving open the possibility that the correlation reflects some aspect of questionnaire-taking behaviour and not an underlying neuropsychological relationship. The present study addressed this issue by administering the Magical Ideation Scale (Eckblad & Chapman, 1983), the Waterloo Handedness Questionnaire-Revised (Elias, Bryden, & Bulman-Fleming, 1998), and a manual dot-filling task (Tapley & Bryden, 1985) as a behavioural measure of handedness to an undergraduate student sample. The expected relationship between magical ideation and handedness as assessed by the questionnaire was observed. However, magical ideation was not related to the behavioural measure of handedness. Results cast doubt on a neuropsychological interpretation of the relationship between handedness and magical ideation in sub-clinical populations. 相似文献
1000.
Composition is an important topic in visual art. The literature suggests a bias for objects on the right side (Levy, 1976) and two additional biases with respect to positioning of objects within a rectangular frame: a Centre bias and an Inward bias (Palmer, Gardner, & Wickens, 2008). We analysed images of animals from three datasets of works of art: two datasets were from artists well known for their portraits of animals (Bewick, Stubbs) and the third was a medieval bestiary. There was no overall displacement of the subject to the right or to the left of the picture. However, we found a bias consisting of more space in front compared to behind the animal, consistent with Palmer at al.'s findings and with their definition of an Inward bias. Because our animals never face towards the centre we use the term Anterior bias. In addition, we found a modulation of this bias on the basis of the facing direction of the animal, consisting of a stronger Anterior bias for left-facing animals. This asymmetry may originate from a combination of an Anterior bias and a Right bias. Finally, with respect to size we found that the size of the animals predicted the proportion of the picture occupied, an effect known as “canonical size”. 相似文献