Ultrasound beam angle-independent evaluation of left ventricular filling pressure using three-dimensional speckle-tracking echocardiography.

Abstract

E/e′ is a major parameter in the algorithm for estimating left ventricular filling pressure (LVFP) by echocardiography.1 However, E and e′ can be affected by Doppler beam malalignment. Moreover, regional e′ is used as an extrapolation of global left ventricular (LV) relaxation. These limitations may cause the estimation of LVFP to be inaccurate in some conditions. In the multicentre Euro-Filling study, E/e′ was weakly correlated with LV end-diastolic pressure but was not an independent parameter correlated with end-diastolic pressure in patients with an ejection fraction (EF) <50%.2 Three-dimensional speckle-tracking echocardiography allows the simultaneous evaluation of LV volume and global myocardial strain. The early diastolic filling rate (FRe), derived from the rate of LV volume change (dV/dt), is theoretically expected to reflect transmitral E, and the early diastolic global strain rate (SRe) correlates with the time constant of global LV relaxation better than e′.3 Furthermore, FRe and SRe are independent of the ultrasound beam angle because they are not measured by the Doppler method. Therefore, FRe/SRe may be used to estimate LVFP, even under conditions where the use of E/e′ is limited. In canine models, we have reported that FRe/SRe correlates well with simultaneously measured LVFP and provides a better estimate of LVFP than E/e′;4,5 however, the utility of FRe/SRe in the clinical setting remains unclear.