NON-INVASIVE EVALUATION OF EFFECTIVE ARTERIAL ELASTANCE: APPLICATION TO MITRAL REGURGITATION

Background: Left ventriculo-atrial pressure gradient, which affects regurgitant fraction (RF) in patients with mitral regurgitation (MR), depends on afterload. However, it is difficult to evaluate afterload quantitatively. Diastolic pressure, pulse pressure, and augmentation index are used as indices of afterload, but these indices do not include the net stroke volume ejected to the aorta, which is essential for the working condition of the heart. In the analysis of ventriculo-arterial interaction, ventricular afterload is represented by an effective arterial elastance (Ea) which is the slope of the arterial end-systolic pressure-stroke volume relationship. We devised an ultrasonic method of obtaining Ea and evaluated the effect of Ea on MR.