Abstract 15254: Time Difference between Onset of Mitral Inflow and Onset of Early Diastolic Mitral Annulus Velocity predicts Left Ventricular End-diastolic Pressure: Assessment by Dual Doppler Echocardiography
Introduction: Time interval (TE-e') between the onset of early transmitral flow velocity (E) and the onset of early diastolic mitral annular velocity (e') has been proposed as an index of left ventricular diastolic function. In previous studies, time from electrocardiographic R wave to the onset of E or e' in different beats were measured and the difference between these time intervals was calculated. A newly developed “Dual Doppler” technique enables us to record transmitral flow and mitral annular velocities simultaneously and the TE-e' can be measured directly.
Hypothesis: The single beat TE-e' predicts left ventricular end-diastolic pressure (LVEDP).
Methods: Subjects consisted of 25 patients (mean age: 70±6 years, 16 male, 9 female) with suspected angina pectoris who underwent cardiac catheterization and 20 age-matched control patients (mean age: 68±6 years, 14 male, 6 female). LV pressure and Dual Doppler recordings were performed simultaneously at baseline and during leg positive pressure (LPP) in the patients group.
Results: TE-e' was greater in the patients group than that in the control group The TE-e' correlated better with LVEDP (r = 0.84, p <0.001) than tau (r = 0.72, p <0.001). There was a good positive linear relationship between the change in LVEDP by LPP and the change in TE-e' (r = 0.65, p <0.001), while the tau did not changed significantly by LPP. A TE-e' value of >33msec predicted LVEDP >15 mmHg with 83.3% sensitivity and 87.5% specificity. The area under the curve for predicting elevated LVEDP was greater for the TE-e' than for the E/e'.
Conclusions: Elevation of LVEDP prolonged the TE-e', suggesting that the elevated LVEDP enhanced early diastolic mismatch between mitral inflow and annular motion. The TE-e' is a sensitive index for noninvasive estimation of LVEDP. Dual Doppler echocardiography is the practical method for measuring this short time interval accurately.
- © 2010 by American Heart Association, Inc.