Background: Mitral regurgitation causes left atrial (LA) and left ventricular (LV) dysfunction, dilatation, and remodeling. Following percutaneous mitral valve repair (PMVR) using the MitraClip® approach, reverse cardiac remodeling is desirable. To date, the influence of PMVR on LA and segmental LV function and remodeling has not been investigated in detail.
Methods: Twenty-six patients who received the MitraClip device were enrolled in an open-label, single-center observational study. Patients underwent clinical assessment, conventional echocardiography and global and segmental longitudinal strain analysis of the left atrium and left ventricle by speckle tracking echocardiography at baseline and at a three-month follow up.
Results: PMVR improved both LV systolic function (from 40.5 ± 2.5% to 45.0 ± 2.5%, p = 0.04) and LV global longitudinal strain (from -8.9 ± 0.7% to -10.7 ± 0.9%, p = 0.004). Segmental analysis revealed improved myocardial deformation mainly in the basal (basalseptal -8.9 ± 0.8% to -12.9 ± 0.8%, p = 0.0002; basallateral -7.9 ± 1.1% to -13.9 ± 1.4%, p = 0.0005) and midventricular segments (mid-septal -12.7 ± 0.9% to -14.5 ± 1.1%, p = 0.02; mid-lateral -7.5 ± 0.8% to -10.8 ± 1.2%, p = 0.006). In patients with pre-procedural preserved LA function with sinus rhythm the impact of PMVR revealed an improvement in LA global conduit function (from 10.6 ± 1.2% to 13.9 ± 1.6%, p = 0.003) and global contractile function (from -2.1 ± 0.47% to -3.5 ± 0.5%, p = 0.03). The reversed remodeling was not associated with altered levels of the cardiac biomarkers matrix metalloproteinase 2 (MMP-2) and MMP-9, tissue-inhibitors of MMPs (TIMP-2 and ST-2).
Conclusions: PMVR improves global segmental LV and LA function and leads to a reverse remodeling.
Trial registration: ClinicalTrials.gov NCT02033811.