Gong-Yuan Xie

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Myalgias and arthralgias are common among workers whose jobs require repetitive isometric maneuvers or malalignment of body position. However, few systematic studies have been performed to evaluate the frequency of these complaints among cardiac ultrasonographers. Therefore the purpose of this study was to determine the prevalence of musculoskeletal pain(More)
The objective of this study was to evaluate the effect of alterations in preload induced by lower body negative pressure on Doppler transmitral filling patterns. Echocardiograms and Doppler recordings were performed in 18 normal young men (aged 23 to 32 years) during various levels of lower body negative pressure (0, -20 and -50 mm Hg). Lower body negative(More)
The tangential contact forces that arise at the interface between the wheel of a railway vehicle and the rail provide all the traction, braking, and guidance required by the vehicle. These forces are the result of microslip or creepage and can become unstable exciting vibration of the wheel, particularly at frequencies corresponding to the wheel’s axial(More)
OBJECTIVES This study was designed to observe left ventricular filling by Doppler echocardiography before and after single lung transplantation in patients with severe pulmonary hypertension. BACKGROUND Right ventricular pressure overload causes the deformation of the left ventricle by septal flattening toward its cavity, which may result in impaired left(More)
OBJECTIVES This study attempted to develop and validate a simple method for calculating aortic regurgitant fraction by use of pulsed wave Doppler echocardiography. BACKGROUND Although several investigators have been able to determine aortic regurgitant fraction by Doppler echocardiography, the methods used require accurate determination of the(More)
Widespread use of echocardiography has contributed to more frequent recognition of takotsubo stress cardiomyopathy. Initial presentation is similar to acute coronary syndrome and the acute course can be complicated by heart failure, arrhythmias, dynamic left ventricular outflow tract obstruction, hypotension and death. We briefly review the clinical(More)
This is an unusual case of a 37-year-old male whose initial presentation to medical care was for dyspnea. A transthoracic echocardiogram was suspicious for cor triatriatum, which was confirmed by transesophageal echocardiography. Since the resting transmembrane gradient was low, a cardiac catheterization with exercise hemodynamics was performed and(More)
We analyzed the relation of Doppler transmitral flow patterns and New York Heart Association (NYHA) classification in 60 consecutive patients with heart failure (44 men and 16 women; mean age 58 +/- 13 years) with left ventricular ejection fraction of < 40 percent. Of the study population, 40 patients with mild to moderate heart failure underwent(More)
The relation of transmitral flow patterns and pulmonary venous velocities was analyzed from 50 heart failure patients (28 men, 22 women; mean [±SD] age 61 ± 9 years) with a left ventricular ejection fraction < 40%. Doppler echocardiography was performed in all patients. Transmitral flow measurements included early (E) and atrial (A) velocities and(More)
In vitro studies have demonstrated that regurgitant flow rate can be estimated by the color Doppler "proximal isovelocity surface area" (PISA) method. By applying the PISA method and continuity principle, we developed a formula to calculate mitral regurgitant volume: 2 pi r2.VN.FVI/Vo, where r = distance from the first jet alias to mitral leaflets, VN =(More)