732 Accurate timing of mitral valve opening by tissue Doppler imaging for an all in one beat analysis

Autor: T. Vartdal, O.A. Smiseth, A. Opdahl, Espen W. Remme, T. Helle-Valle
Rok vydání: 2006
Předmět:
Zdroj: European Journal of Echocardiography. 7:S122-S122
ISSN: 1525-2167
DOI: 10.1016/s1525-2167(06)60455-1
Popis: Background: Echocardiographic indices of diastolic function are largely dependent on accurate timing of mitral valve opening (MVO). Determination of MVO in the same heart beat as other derived echocardiographic measures is crucial to avoid inaccuracies caused by beat to beat variation. The aim of the study was to investigate if tissue Doppler imaging (TDI) information can be used to determine MVO. Methods: In anaesthetised mongrel dogs (n=4) with left atrial (LA) and LV micromanometers, MVO was defined as the time of first diastolic LA/LV pressure crossover (MVOPCO), which is when the pressure gradient starts separating the valve leaflets. In apical projections, the TDI signal from a sample volume positioned at the mitral leaflet tips was used to define MVOTDI as the time of onset of rapid increase of positive velocity in early diastole (figure, left panel). MVO was measured by the two methods and compared during different loading conditions, increased inotropy, and during ischaemia. In 6 patients with acute myocardial infarction and in 6 healthy subjects we compared MVOTDI with timing of onset of mitral flow by Doppler (MVODoppler). Results: In the experimental study MVOTDI showed very good agreement with MVOPCO: mean difference: 1.7±9.8 ms (2SD); correlation: r=0.99, p
Databáze: OpenAIRE