OBJECTIVES We used the Doppler proximal flow convergence technique as a physiologic tool to explore the effects of the time courses of mitral annular area and transmitral pressure on dynamic changes in regurgitant orifice area. BACKGROUND In functional mitral regurgitation (MR), regurgitant flow rate and orifice area display a unique pattern, with peaks in early and late systole and a midsyst...

Measurements of film mass flow rate for annular, diabatic steam-water flow in tubes are presented. The measurements were carried out with four axial power distributions and at several axial positions at conditions typical for boiling water reactors, i.e. 7 MPa pressure and total mass flux in a range from 750 to 1750 kg/ms. The results show that the influence of the axial power distribution on t...

Abstract Transcatheter aortic valve implantation (TAVI) has revolutionized the treatment of patients with severe, symptomatic stenosis. Despite being less invasive than conventional open-chest surgery, TAVI remains associated rare but serious complications such as vascular injury, stroke, coronary obstruction, cardiac perforation and annular rupture. We report a case combined rupture successful...

OBJECTIVES This study assessed apparently normal mitral valves from patients with congestive heart failure (CHF) using biochemical and echocardiographic measures of extracellular matrix (ECM) and anatomy. BACKGROUND Mitral regurgitation (MR) is frequently found in patients with CHF. This MR is considered purely functional, yet animal studies suggest that altered left ventricular (LV) function...

OBJECTIVE To evaluate new echocardiographic modes in the diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC). DESIGN Prospective observational study. SETTING University Hospital. SUBJECTS 15 patients with ARVC and a control group of 25 healthy subjects. METHODS Transthoracic echocardiography included cross sectional measurements of the right ventricular outflow tract, ri...

Precise fluid flow control is one of the most important aspects of many chemical processing systems, both reactive and analytical. Recent research has led to a sensor capable of very precisely measuring mass flows up to 1g/h, based on the Coriolis principle. However, applying such a measurement in a flow control system is not yet possible, as valves capable of regulating such small flows do not...

Original scientific paper The necessary forces for the control of a hydraulic sliding-spool valve are normally determined by the stationary axial momentum forces of the oil flow through a valve. These forces increase with an increase in the volume flow and the pressure difference. Because of the limited actuating-force potential of normal electromechanical actuators, the direct actuation of con...

OBJECTIVES Precise measurements of aortic annulus dimensions are crucial for prosthesis size selection in patients undergoing transcatheter aortic valve implantation (TAVI). The so-called effective diameter (derived from area) measured in multislice computed tomography (MSCT) images has evolved to be the most precise measurement tool. Usually, the operator must manually adjust the aortic annula...