Long-term clinical and echocardiographic outcomes of Mitraclip therapy in patients nonresponders to cardiac resynchronization.

OBJECTIVES: This study deals with clinical and echocardiographic outcomes in cardiac resynchronization therapy (CRT) nonresponders patients undergoing Mitraclip procedure.

BACKGROUND: Functional mitral regurgitation (FMR) occurs in approximately one-third of heart failure (HF) patients. Resynchronization therapy may correct FMR in patients with HF; however, significant FMR persists in 20-25% of CRT patients.

METHODS: All patients included were previously treated with CRT for at least 6 months and remained classified as New York Heart Association (NYHA) functional class III or IV despite optimal medical therapy; the echocardiographic assessment showed lack of decrease of the left ventricular end-systolic volume (LVESV) of at least 10% and residual moderate-to-severe or severe FMR. Clinical and echocardiographic follow-up was scheduled at 1, 3, 6, and 12 months after Mitraclip implantation, and every 6 months thereafter.

RESULTS: Thirty patients fulfilled inclusion criteria. Before Mitraclip implantation NYHA class was III in 83% and IV in 17% of patients; after CRT no patient experienced an improvement in FMR. There was a significant improvement in NYHA class from baseline to 6 months, which remained sustained at 12 and 24 months. The degree of FMR significantly improved from baseline to 6 months and from 6 to 12 months. There was left ventricle remodeling with significant reduction of LVESV and an increase of left ventricle ejection fraction at 6 and 12 months, while the opposite trend was noted between 12 and 24 months CONCLUSION: Treatment of moderate to severe FMR in CRT nonresponder is feasible, safe, and reasonably effective in reducing cardiac symptoms.