BACKGROUND Precise knowledge of left atrial appendage (LAA) orifice size is crucial for correct sizing of LAA closure devices. The aim of the present study was to determine the performance of real-time 3D transesophageal echocardiography (RT3DTEE) for LAA orifice size assessment, compared with 2D transesophageal echocardiography (2DTEE), and to investigate the impact of atrial fibrillation (AF)...

Background Precise knowledge of left atrial appendage (LAA) orifice size is crucial for correct sizing of LAA closure devices. Aim of the present study was to determine the performance of real-time three-dimensional transesophageal echocardiography (RT3DTEE) for LAA orifice size assessment, compared to twodimensional transesophageal echocardiography (2DTEE), and to investigate the impact of atr...

AIMS Pulsed Doppler measurement of left atrial appendage (LAA) emptying velocity, a marker of left atrium contractile function, has been shown to predict success of cardioversion, thrombo-embolic risk, and maintenance of sinus rhythm after cardioversion and pulmonary vein isolation. However, in the published literature, emptying velocity measurement location is not uniform, and no standard curr...

Investigating nozzle’s orifice flow is challenging both experimentally and theoretically. This paper focuses on simulating flow inside diesel injector nozzle via Ansys fluent v15. Validation is performed with experimental results from Winkhofler et al (2001). Several important parameters such as mass flow rate, velocity profiles and pressure profiles are used for this validation. Results includ...

The objective of this paper is to understand how and why the orifice nature (rigid or flexible) governs the bubble generation. The differences in orifice nature and properties have strong consequences on the bubbles generated. Indeed, the dynamics of the formation and the nature of the detached bubbles are fundamentally different depending on whether the bubbles are generated from the rigid ori...

OBJECTIVE The purpose of this study was to evaluate the shaping ability of three nickel-titanium systems in simulated curved canals. MATERIALS AND METHODS Sixty simulated canals were prepared to apical size 25 with Reciproc, S5, and twisted file (TF) instruments. Standardized pre and postoperative images were taken using a digital camera, were superimposed and aberrations were recorded. Mater...

This article investigates through experiments the flow characteristics of plane jets from sharp-edged orifice-plate, beveled-edge and radially contoured nozzle. The first two configurations exhibit saddle-backed velocity profiles while the third shows a top-hat. A vena contracta is found for the jet emanating from orifice at x/h ≈ 3 while the contoured case displays a potential core extending t...

Analysis of velocity acceleration proximal to a regurgitant valve has been proposed as a method to quantify the regurgitant flow rate (Qo). Previous work has assumed inviscid flow through an infinitesimal orifice, predicting hemispheric isovelocity shells, with calculated flow rate given by Qc = 2 pi rN2vN, where vN is user-selected velocity of interest and rN is the distance from that velocity...