Echocardiographic examination
Two- and three-dimensional (2D and 3D) TTE was performed on each participant using Philips Epic 7C system (Philips Medical Systems, Andover, MA, USA) and Philips X5-1 matrix Probe. One echocardiographer performed the 2D and 3D TTE and further measurements and analysis using post-processing software (TomTec version 4.6).
The 3D LV evaluated the 3D volumes, EF, SVI, GLS, GCS, GRS, twist, and torsion values using Tomtec dedicated application for 3D LV analysis. The diastolic indexes were determined using tissue Doppler imaging. An RV anatomical evaluation, including 3D RV volumes, EF, and FAC, was performed using a 3D RV analysis method (TomTec V 4.6). TAPSE by M-Mode and Peak basal systolic RV tissue velocity by tissue Doppler imaging served as RVsm. RVFWGLS strain and Peak SR were determined using the RV-focus view of the 2D Tomtec strain software.
Left and right atrial (LA and RA) evaluation performed via speckle tracking technique and TomTec V 4.6 dedicated application for atrial strain, utilizing standard four-chamber views, and in accordance with the expert consensus recommendations for standardization of LA and RA strain published in the European Journal of echocardiography (10). The calculation of sPAP was based on tricuspid regurgitation gradient plus RA pressure (defined by inferior vena cava size and collapsibility).
Valvular regurgitation and severity were examined, and patients with moderate or severe regurgitation or stenosis were eliminated from the research.