Abstract 702: Diastolic Intraventricular Pressure Gradients Assessed by Color M-Mode Echocardiography
Diastolic flow is governed by an intraventricular pressure gradient. We hypothesized that normal ventricles exhibit a pressure gradient that extends further toward the apex than do diseased ventricles. One hundred echocardiograms were retrospectively selected for analysis based on the quality of Doppler color M-mode signals. Color M-mode signals were analyzed with an automated algorithm that reconstructed the velocity fields using a least squares fit technique and then corrected the aliased regions. Using the Navier-Stokes equation, these velocity fields were converted to relative pressure distributions from the mitral valve to the apex (Figure 1⇓). There was a progressive pressure gradient extending a variable distance towards the apex. This distance correlated negatively with the E/E′ ratio (Figure 2⇓). Normally a progressive diastolic pressure gradient extends from the mitral valve to the towards the LV apex. With diastolic dysfunction (increased E/E′), the gradient stops closer to the mitral valve.