Myocardial fibrosis predicts adverse outcome after MitraClip implantation.

Background: High-risk patients with mitral regurgitation (MR) may be treated by a percutaneous mitral valve repair with the MitraClip, but identification of patients who may benefit remains difficult. We aimed to determine whether myocardial fibrosis predicts outcome in MR patients undergoing MitraClip implantation and is beneficial in clinical decision making.

Methods: Preprocedural to the MitraClip implantation, myocardial fibrosis was analyzed with cardiovascular magnetic resonance (CMR) through late gadolinium enhancement. The CMR data were core-lab adjudicated measured before the MitraClip implantation. Adverse outcome was defined as New York Heart Association (NYHA) class III or IV after 1 month or death within 1 month after the MitraClip implantation.

Results: In total, 23 patients underwent preprocedural CMR, mean age 80 ± 9 years, 45% male, 64% atrial fibrillation and 73% NYHA class III or IV at baseline. Myocardial fibrosis was present in 55% of the patients with degenerative MR and in 64% of the patients with functional MR. An adverse outcome occurred in 69% of the patients with myocardial fibrosis and in 11% of the patients without myocardial fibrosis (P = 0.01).

Conclusions: Our hypothesis-generating study showed that the presence of myocardial fibrosis predicts adverse outcome in patients undergoing MitraClip implantation. After confirmation with larger sample size, identification of myocardial fibrosis might contribute to assess prognosis and to clinical decision making.