Two-Dimensional Speckle-Tracking Echocardiography
Commercially available software (TOMTEC Imaging Systems, Munich, Germany) was used to obtain 2DSTE at frame rates between 40 to 80 frames/sec. Left ventricular GLS was obtained in the standard 2-, 3-, and 4-chamber apical views by averaging the peak systolic strain in all segments. A third, blinded reviewer analyzed LA strain on TOMTEC, including measures of PALS and PACS. PALS was measured in 4- and 2-chamber views, the values of which were averaged to determine mean PALS. Similarly, PACS was measured across 4- and 2-chamber views, and averaged to determine mean PACS. Conduit strain was calculated as the difference between PALS and PACS.