478 ventricular and atrial remodeling after edge-to-edge trans-catheter mitral valve repair: a pilot study

Abstract Background Percutaneous mitral valve repair (PMVR) is an established therapy for mitral regurgitation (MR) in patients at high risk for surgical treatment. The aim of this study was to determine the impact of PMVR on left and right ventricular (LV, RV) and left and right atrial (LA, RA) remodelling according to the mechanism of MR and history of atrial fibrillation (AF). Methods and results Twenty-four patients (mean age 78.54 years ± 7.64 SD; 62.5% males) undergoing PMVR at our centre were prospectively enrolled. All the patients underwent echocardiography 1.6 ± 0.9 months before the procedure and after 5.7 ± 3.5 months; functional MR accounted for 54% of cases. Compared to baseline, a statistically significant improvement in LV end-diastolic diameter (LVEDD), LV indexed mass (ILVM), LV end-diastolic and end-systolic volumes (LVEDV, LVESV), indexed LA volume (iLAV) and morpho-functional RV parameters was recorded. LVEDD and LVEDV improved in primary MR cohort whereas in secondary MR a significant reduction in LVEDV and LVESV with a nonsignificant improvement in ejection fraction were found. (Table 1) LA positive remodelling was found in organic MR with a trend toward ameliorated function; in functional MR, with more dilated and dysfunctional LA, no significant improvement was found. (Table 1) Furthermore, a significant reduction of LA volumetry was detected only in patients without history of AF (AF baseline 51.4 mL/m2 IQR 45.6-62.5 mL/m2 f-u 48.9 mL/m2 IQR 42.9-59.2 mL/m2; p=0.101; no AF baseline 43.5 mL/m2 IQR 34.2-60.5 mL/m2 f-u 42.0 mL/m2 IQR 32.0-46.2 mL/m2; p=0.012). As regards right sections, the most relevant positive remodeling was obtained in patients with functional MR with a baseline poorer RV function and more severe RA and RV dilation. (Table 1) Conclusion At mid-term follow-up after PMVR, a positive cardiac remodeling is detected in atrial and ventricular chambers also involving the right sections. To deliver a tailored intervention, MR mechanism and history of AF should be considered in view of the impact on remodeling process.