2.2. Echocardiographic studies
Transthoracic echocardiography (TTE) was routinely performed before and 7-14 days after mitral valve repair. Left ventricular (LV) diastolic dimension, LV systolic dimension, indexed LV mass, LV ejection fraction (EF), LA dimension, the severity of MR (none, mild, moderate or severe), mean transmitral pressure gradient (TMPG), the severity of tricuspid regurgitation (none, mild, moderate or severe) and peak systolic transtricuspid pressure gradient were evaluated according to the guidelines.4-7 Post-operative functional MS was considered significant when a mean TMPG was ≥ 5 mmHg, despite the absence of apparent sclerosis of the leaflets or a moderate or more degree of residual MR. The aorto-mitral angle was measured from the recorded digital images as the intersection angle of the mitral annulus ring and aortic valve plane at end-diastolic on parasternal long axis images, as shown in Figure 1.3