Echocardiographic image tracker with a speckle adaptive noise reduction filter for the automatic measurement of the left atrial volume curve

AIMS: Since tracking accuracy in left atrial (LA) images decreases due to low image quality around the LA in the apical view, a practical tracking method for LA images has not yet been proposed. The aim of this study was to assess an accurate and high-speed LA volume tracking (LAVT) method for the automatic measurement of LA volume (LAV) curves. METHODS AND RESULTS: We used three approved protocols in this study: (i) LAV curves were measured by LAVT on computer-simulated images; (ii) in 20 healthy volunteers, we assessed the feasibility and accuracy of this method compared with expert's measurements; and (iii) echocardiography and multi-detector row computed tomography (MDCT) imaging were performed on the same day in 20 patients with suspected coronary artery disease. On computer-simulated images, mean absolute percentage LAVT error in one cardiac cycle was 3% in filtered images and 16% in original images. In 20 healthy volunteers, there are strong correlations between LAVT and the expert's LA measurements (LA maximum volume; R = 0.93, P < 0.001). In 400 LA images with 20 patients, an excellent correlation was obtained between LAVs using echocardiography and MDCT (R = 0.98, P < 0.001), with a small bias (-14% of the mean) and narrow limits of agreement (+15% of the mean). The mean time required for the LAVT analysis was 1.8 min, for the MDCT analysis was 35.8 min, and for the manual echocardiographic analysis was 14.0 min. CONCLUSION: This LAVT method is fast, valid, accurate, and reproducible for determining LAV in both simulated images and the clinical setting.