Safety and outcomes of MitraClip implantation in functional mitral regurgitation according to degree of left ventricular dysfunction.

INTRODUCTION AND

OBJECTIVES

Recent randomized trials of the MitraClip system have reported controversial results in the treatment of patients with functional mitral regurgitation (FMR). The aim of the present study was to evaluate the safety and impact of MitraClip implantation on outcomes in FMR according to left ventricular (LV) status.

METHODS

Patients with FMR undergoing MitraClip implantation in our center were retrospectively screened and divided into 2 groups according to LV ejection fraction (LVEF) and LV end-diastolic dimension: "very poor LV" (LVEF ≤ 20% and/or LV end-diastolic dimension ≥ 70 mm) and "poor LV" (LVEF> 20% and LV end-diastolic dimension <70 mm). Survival analysis of cardiovascular outcomes included hospital admission due to congestive heart failure, heart transplant, and cardiovascular death. Likewise, we compared the number of hospital admissions and functional class the year before and after the intervention.

RESULTS

Fifty-eight consecutive patients with FMR were included (28 with very poor LV and 30 with poor LV). The mean follow-up was 19.5± 13 months. Patients with poor LV showed a significantly better event-free survival for cardiovascular events (log-rank 3.706, P=.010). One year after the intervention, both groups showed symptom improvement. Most of the patients were in New York Heart Association functional class I-II (100% poor LV and 84% very poor LV) and both groups showed a decrease in the number of hospital admissions due to congestive heart failure.

CONCLUSIONS

MitraClip implantation seems to be safe and effective in reducing FMR. Although patients with very low LVEF and/or very enlarged LV seemed to have worse cardiovascular outcomes, the intervention was safe and resulted in symptom improvement.