Analysis and experiment show that to supercharge the suction volume of a cylinder by means of pressure pulsation is not certain to result in delay of the valve closing. To arrange a proper suction pipeline and valve cavity, we can not only get supercharge of the cylinder, but also,get economical specific power consumption, while valve working condition is good too. In this paper the methods of ...

In this study, the long-term function of St. Jude Medical valve (SJM valve) is evaluated by Doppler echocardiography. The subjects were 191 patients who underwent mitral or aortic valve replacement using SJM valve in our institute since July 1978 and had no clinical problem showing more than 50% of left ventricular ejection fraction. The patients were classified into 3 groups according to measu...

Clinical and experimental evidences of limitations of the simplified Bernoulli equation for assessing pressure difference across nonobstructive valves. Role of inertial forces. Doppler echocardiography has been validated extensively for the assessment of the magnitude and time course of the pressure difference across a stenotic valve using the so-called “simplified” Bernoulli equation: pressure...

introduction:  in patients who underwent surgery to repair tetralogy of fallot, right ventricular dilation from pulmonary regurgitation may be result in right ventricular failure, arrhythmias and cardiac arrest. hence, pulmonary valve replacement may be necessary to reduce right ventricular volume overload. the aim of present study was to assess the effects of pulmonary valve replacement on rig...

AIMS To synthesize by meta-analysis the findings of recent experimental studies focusing on possible therapeutic effectiveness of statins for nonrheumatic calcific aortic stenosis. METHODS Observational studies and randomized controlled trials (RCTs) were selected from the Pubmed database to evaluate the hemodynamic progression of aortic stenosis in statin-treated patients compared with contr...

To achieve the accurate measurement of the hydraulic valve opening position, the sensor measurement circuit was designed for two and three differential solenoid coil inductance displacement sensor. Some experiments were done to detect the static and dynamic performance. Comparing the static output characteristic of the two type of the sensor. The experimental results of the actual measurement o...

The #ow structures generated by a pressure-controlled self-oscillating valve are investigated both experimentally and numerically. Schlieren #ow visualization experiments show that a stable vortex is developed downstream of the valve during the closing phase of the valve. During the opening phase of the valve, this vortex moves downstream and dissipates. An experimental study of the vortex inte...

OBJECTIVE The diagnosis of shunt malfunction can be challenging since neuroimaging results are not always correlated with clinical outcomes. The purpose of this study was to evaluate the efficacy of a simple, minimally invasive cerebrospinal fluid (CSF) lumbar tapping test that predicts shunt under-drainage in hydrocephalus patients. METHODS We retrospectively reviewed the clinical and radiol...

BACKGROUND The Melody valve is approved for percutaneous pulmonary valve replacement in dysfunctional right ventricular outflow tracts. The function of this valve when subjected to high-pressure loads in humans is unknown. The aim of this study was to describe the immediate and short-term results of Melody valves implanted in a high-pressure environment. METHODS AND RESULTS Definitions of a h...