A new approach to noninvasive estimation of stenotic orifice area in semilunar valve stenosis by Doppler echocardiography

In stenotic heart valve diseases, quantitative Doppler echocardiography provides the reliable estimation of the pressure gradient across the stenotic valve [1–9]. Although the pressure gradient is a practically useful parameter to evaluate the severity of stenotic valve lesions, it essentially depends on flow rate. For a given stenotic orifice, it may vary with the changes in the hemodynamic state of the heart, and not be simply regarded as an absolute measure of the obstruction.