Quantification of left atrial volumes using three-dimensional wall motion tracking echocardiographic technology: comparison with cardiac magnetic resonance

Abstract

Left atrium (LA) size assessment is clinically relevant, but the accuracy of two-dimensional echocardiographic (2D-echo) methods is limited. Three-dimensional (3D) echocardiography is an excellent alternative but is far from being used in daily clinical practice. Three-dimensional-wall motion tracking (3D-WMT) allows us to obtain volumes in a very simple and rapid manner. The aims of this study were to evaluate the accuracy of 3D-WMT technology to assess LA volume using cardiac magnetic resonance (CMR) as a reference method, to evaluate its reproducibility, and to determine its added clinical value to classify the LA enlargement severity. Seventy consecutive patients referred for a CMR study were prospectively enrolled. They underwent LA volume assessment by means of 2D-echo, 3D-WMT, and CMR. Inter-methods agreement was assessed. The mean age was 56 ± 18 years and 42 patients (60%) were males. Average maximal LA volume obtained by 2D-echo, 3D-WMT, and CMR were 63.33 ± 26.82, 79.80 ± 29.0, and 79.80 ± 28.99 mL, respectively. Univariate linear regression analysis showed a good correlation between 3D-WMT and CMR (r = 0.83; P < 0.001). The agreement analysis showed a similar result (ICC = 0.83; 95% CI = 0.74-0.89; P < 0.001). Furthermore, the LA enlargement degree was better evaluated with 3D-WMT than with 2D-echo. This study validates LA volume measurements obtained using the new and fast 3D-WMT technology, compared with CMR. This method is fast, accurate, and reproducible, and it allows a better classification of left LA enlargement severity compared with 2D-echo.