Left ventricular (LV) pressure-strain loops (PSLs) have been recently validated as a non-invasive index of myocardial performance. Aim of the present study is to compare LV function, myocardial work, and energy dispersion in patients with severe secondary mitral regurgitation (MR) and decreased left ventricular ejection fraction (LVEF) before percutaneous mitral valve repair (PMVR, by Mitraclip® system) and at 6-month follow-up (FU) compared to optimal medical treatment.

We included in this study 56 patients (mean age: 72years) with secondary MR and decreased LVEF. Thirty-seven undergoing PMVR according to local heart team compared with 19 with optimal medical treatment. All patients underwent standard echocardiography and speckle tracking echocardiography (STE) at inclusion and at 6-month FU. Strain traces and valvular event times were used to calculate LV-PSLs and Global Work Index (GWI), Constructive Work (CW), and Wasted work (WW) were therefore obtained.

The main results are shown in Table 1. Despite a strongest decrease of NYHA class (2.6±0.6 vs. 1.8±0.7; P<0.0001) in PMVR group, no significant difference in LV function and remodeling parameters was observed at FU between both groups. Interestingly, whereas GWI and WW remained unchanged, CW significantly improved in the same proportion at 6-month FU in both groups (1101 vs. 977; P=0.003 and 1110 vs. 967mmHg.%, P=0,002).

On the contrary than patients with severe MR and high surgical risk undergoing optimal medical treatment, patients undergoing PMVR experienced a significant improvement in symptoms. On the other hand, the evolution of classical parameters of LV function/remodeling as well as new indices of myocardial work was not different. These findings support the hypothesis that the symptoms improvement result in another mechanism than a left ventricular remodeling.