BACKGROUND Although Doppler color flow mapping is widely used to assess the severity of mitral regurgitation (MR), a simple, accurate, and quantitative marker of MR by color flow mapping remains elusive. We hypothesized that vena contracta width by color flow mapping would accurately predict the severity of MR. METHODS AND RESULTS We studied 80 patients with MR. Vena contracta width was measu...

An axisymmetric jet issued from a sharp edged circular convergent nozzle has been studied experimentally in the near field at Reynolds number 5.3x104  to search the saddle shape behavior of mean velocity and the role of mean static pressure in the jet flow. Due to the vena contracta effect the centerline mean velocity of the jet increases about 4.2% of its exit value and corresponding decrease ...

Mitral regurgitation (MR) severity is routinely assessed by Doppler color flow mapping, which is subject to technical and hemodynamic variables. Vena contracta width may be less influenced by hemodynamic variables and has previously been shown to correlate with angiographic estimates of MR severity. This study was performed to compare mitral vena contracta width by multiplane transesophageal ec...

BACKGROUND Flow-rate dependencies of the Doppler continuity equation are addressed in this study. METHODS AND RESULTS By use of computational fluid dynamic (CFD) software with turbulence modeling, three-dimensional axisymmetric models of round stenotic orifices were created. Flow simulations were run for various orifice area sizes (0.785, 1.13, 1.76, and 3.14 cm2) and flow rates (0.37 to 25.0...

In presence of aortic stenosis, a jet is produced downstream of the aortic valve annulus during systole. The vena contracta corresponds to the location where the cross-sectional area of the flow jet is minimal. The maximal transvalvular pressure gradient (TPG(max)) is the difference between the static pressure in the left ventricle and that in the vena contracta. TPG(max) is highly time-depende...

M itral regurgitation (MR) is a common form of valvular disease1 and its severity is associated with excess morbidity and mortality from left ventricular (LV) remodeling, left atrial remodeling, pulmonary pressure elevation, and progression to left and right heart failure.2-6 Current American Society of Echocardiography (ASE) Guidelines7 propose vena contracta (VC) width as a simple semi-quanti...

BACKGROUND The anatomic opening area (AOA) is usually reported as the primary index of mechanical heart valve function. Because flow contracts immediately distal to an orifice as a result of the vena contracta effect, AOA may not be a good measure of true effective flow area. METHODS AND RESULTS Laser flow imaging was used to visualize the contraction in the jet flow stream as it passed throu...

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...

OBJECTIVES This study was performed to validate the accuracy of color flow vena contracta (VC) measurements of aortic regurgitation (AR) severity by comparing them to simultaneous intraoperative flow probe measurements of regurgitant fraction (RgF) and regurgitant volume (RgV). BACKGROUND Color Doppler imaging of the vena contracta has emerged as a simple and reliable measure of the severity ...

OBJECTIVE To evaluate the ability of colour Doppler transoesophageal echocardiography (TOE) to assess quantitatively prosthetic mitral valve insufficiency. METHODS 47 patients were studied with multiplane TOE and cardiac catheterisation. Proximal jet diameter was measured as the largest diameter of the vena contracta. Regurgitant area was measured by planimetry of the largest turbulent jet du...