Echocardiography examination
All echocardiography exams were performed using Vivid E95, (General Electric; Horten, Norway) with a standard transducer of 1.7–4 Hz. The frame rate during echocardiography examinations was greater than or equal to 40 frames per second. Comprehensive transthoracic echocardiography examinations were performed according to the latest recommendations on chamber quantificationBiplane left atrial volume index (LAVi) was calculated according to the following formula:Left ventricular mass index (LVMi) was calculated according to the following formula:All echocardiography examinations were then transferred to the EchoPAC workstation (Version 204), for further off-line speckle-tracking imaging analysis. Speckle tracking imaging analysis was done according to the original recommendations from the apical views