الفهرس 
INTRODUCTION AND AIM OF THE STUDYيوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
Determination of mitral valve area is of clinical
importance in assessing the severity of mitral stenosis
because valve area is not altered in various hemodynamic
conditions (Braunwald, 1992).
The evaluation and follow-up of patients-with mitral
stenosis require a reliable non invasive’method for assessing
mitral valve area.
Two-dimensional echo cardiography used to be the most
widely used method for quantifying mitral valve area.
However, when the mitral valve is extensively distorted or
severely calcified accurate measurement of its area by this
method may not be feasible. Moreover, two-dimensional echo
cardiography is highly dependent on optimal technique both in
achieving the proper gain settings and in locating the true
mitral orifice in the short axis view (Smith, 1986).
Pressure half-time method proposed by Hatla et al.
(1977) has also gained wide spread acceptance as a non
invasive form of assessing mitral valve area. However,
several reports have indicated that this method cannot
accurately estimate the mitral valve area in the presence of
aortic regurgitation and left ventricular dysfunction.
Recent investigation have demonstrated that Doppler
color flow imaging allows estimation of the severity of the
stenotic lesion and the size of the defect in cardiovascular system (Pollick, 1988). Some reports have indicated the
width of the central laminar core just at the orifice
corresponds to the actual orifice diameter. Therefore,
accurate measurement of the width of the color jet passing
through the mitral valve orifice may provide quantitive
assessment of the severity of mitral stenosis.