Search

Intraventricular velocity distribution reflects left ventricular (LV) diastolic function and can be measured non-invasively by flow mapping technologies. We designed our study to compare intraventricular velocities and gradients, obtained by vector flow mapping (VFM) technology during early diastole in consecutive patients diagnosed with mild and advanced diastolic dysfunction at echocardiography and a control group with a purpose to validate the hypothesis of relationship between new parameters and severity of diastolic dysfunction and conventional markers of elevated LV filling pressure. Two-dimensional streamline fields were obtained using VFM technology in 121 subjects (57 with normal diastolic function, 38 with mild diastolic dysfunction and 26 with advanced diastolic dysfunction). We measured several velocities and calculated a gradient along the selected streamline, which we compared between groups and correlated them with conventional echocardiographic parameters. Apical intraventricular velocity gradient (GrIV) was the lowest in control group, followed by mild and advanced diastolic dysfunction groups (5.3 ± 1.9 vs. 6.8 ± 2.5 vs. 13.6 ± 5.0/s, p < 0.001) and showed good correlation with E/e' (r = 0.751, p < 000.1). GrIV/e' ratio was the strongest single predictor of severity of diastolic dysfunction. Different degrees of diastolic dysfunction affect the Intraventricular velocity behavior during early diastole obtained by VFM. GrIV could discriminate between groups with different levels of diastolic dysfunction and was closely associated with classical echocardiographic indices of elevated LV filling pressure. GrIV/e' ratio has a potential to become a single parameter needed to assess left ventricular diastolic function. [ABSTRACT FROM AUTHOR]

The indication for surgery in asymptomatic severe mitral regurgitation (SMR) with preserved left ventricular ejection fraction (LVEF) is controversial. We sought to study 3D myocardial mechanics in this population and test 3D-speckle tracking (3DST) parameters as possible predictors of events. 45 asymptomatic patients with SMR and LVEF >60 % and 20 control individuals without cardiac disease underwent 3DST echocardiography. MR group additionally underwent further clinical monitoring. Dyspnea, LVEF under 60 %, or admissions for heart failure were considered as events. When compared with control group, MR group showed lower percentage of global 3D strain, (35.4 ± 9.1 vs. 43.9 ± 10.6; p = 0.003), lower radial strain, lower area change rate and higher end-diastolic volume. In a follow-up time of 23.2 ± 14.5 months we found 15 events (33.3 %). When comparing the remaining patients with this new-onset HF group we found significant differences in longitudinal strain (-17.9 ± 3.3 vs. -15.8 ± 2.1; p = 0.036), area strain (AS) (-48.6 ± 4.6 vs. -43.7 ± 6.2; p = 0.006), circumferential strain (-35.8 ± 4.7 vs. -31.8 ± 6.1; p = 0.034), 3D LVEF (67.1 ± 4.6 vs. 63.0 ± 7.4; p = 0.034) and E/E' index (13.5 ± 3.9 vs. 19.3 ± 9.5; p = 0.006). In multivariate Cox regression AS alone was the only independent predictor. A cutoff value of AS greater than -41.6 % reached a hazard ratio of 4.41 (p = 0.004) for prediction of events. In asymptomatic patients with SMR and preserved ejection fraction, 3DST derived AS is a promising tool for predicting the development of heart failure. This finding may be useful for guiding the selection of patients for early mitral valve repair/replacement surgery even if they are asymptomatic. [ABSTRACT FROM AUTHOR]