Abstract 13311: Relation of Early Diastolic Mitral Annular Velocity, Mitral Flow Velocity, and Left Ventricular Strain Rate on Intraventricular Pressure Difference
Background: The early diastolic mitral annular Doppler velocity (e′), indicating the rate of longitudinal left ventricular (LV) expansion, delays with the progression of diastolic dysfunction (DD). This makes e′ relatively independent from intraventricular pressure difference (IVPD) from left atrium (LA) to LV in the presence of DD. However, it is unknown whether circumferential wall expansion delays and is independent from IVPD in DD.
Methods: Echocardiography was performed in 127 patients. Time-global strain rate curves were extracted by using two-dimensional speckle tracking. The early diastolic peak of longitudinal and circumferential global strain rates (SRE) were measured. The time from the QRS wave to the peak point was measured for early diastolic LV inflow (E), longitudinal SRE, and circumferential SRE. The IVPD from LA to apex was determined using color M-mode Doppler data to integrate the Euler equation. Diastolic function was graded according to the ASE recommendation.
Results: DD was classified as group 1 (normal or impaired relaxation, N=53) and group 2 (pseudonormal or restrictive filling, N=74). In group 1, longitudinal SRE and circumferential SRE occurred slightly earlier than E (longitudinal SRE: 514±52 ms, P<0.05 vs E; circumferential SRE: 508±52 ms, P<0.01 vs E; E: 520±55 ms). In contrast, in DD, longitudinal SRE occurred later than E (537±58 vs 529±56 ms, P<0.01) whereas circumferential SRE occurred earlier than E (520±65 vs 529±56 ms, P<0.05). The slopes of regression lines of e′ or longitudinal SRE and IVPD were significantly lower in group 2 than in group 1 whereas those of E or circumferential SRE and IVPD were similar between the groups. (Figure ).
Conclusion: The early diastolic longitudinal expansion is delayed in the presence of DD, which makes it relatively independent of the elevated IVPD. In contrast, circumferential wall expansion occurs with LV filling regardless the presence of DD, resulting in being influenced by IVPD in DD.
- © 2013 by American Heart Association, Inc.