Mitraclip therapy and surgical mitral repair in patients with moderate to severe left ventricular failure causing functional mitral regurgitation: a single-centre experience.

OBJECTIVES: Surgical mitral repair is the conventional treatment for severe symptomatic functional mitral regurgitation (FMR). Mitraclip therapy is an emerging option for selected high-risk patients with FMR. The aim of this study was to report the outcomes of patients who underwent a surgical mitral repair and Mitraclip therapy for FMR in our experience.

METHODS: From March 2000 and April 2011, 143 patients with FMR were treated in our institution: 91 patients (63.6%) underwent surgical mitral repair (49% ischaemic; 51% idiopathic) and 52 (36.4%) underwent Mitraclip implantation (71% ischaemic; 29% idiopathic). Associated procedures in the surgical group were myocardial revascularization in 35%, tricuspid repair in 25% and atrial fibrillation ablation in 26%. Follow-up was 100% complete (median 18; 6.4-45 months for surgery and 8.5; 4-12 months for Mitraclip).

RESULTS: Mitraclip patients were older (P = 0.04), had higher log EuroSCORE (P < 0.0001), lower LVEF (P = 0.006) and higher left ventricular diameter (P = 0.01 for left ventricular end-diastolic diameter and P = 0.05 for left ventricular end-systolic diameter). Major postoperative infection or sepsis occurrence was higher in the surgical group (16.3 vs. 3.8%; P = 0.01), while no differences were observed in terms of acute renal failure, cardiogenic shock, cerebrovascular accident and acute myocardial infarction. Length-of-stay was 11 days (IQR: 7-19 days) for surgery and 5 days (IQR: 4-9 days) for MitraClip (P < 0.0001). In-hospital mortality was 6.6% for surgery (6/91) and 0% for Mitraclip (P = 0.01). Surgery was identified as a predictor of in-hospital death (OR: 2.61; P = 0.01). Residual MR ≥ 3+ at discharge was 0% for surgery and 9.6% for Mitraclip (P = 0.002). At follow-up, actuarial survival at 1 year was 88.9 ± 3.5% for surgery and 87.5 ± 7% for Mitraclip (P = 0.6). Actuarial freedom from MR ≥ 3+ at 1 year was 79.1 ± 8% for MitraClip and 94 ± 2% for surgery (P = 0.01). At last follow-up, most of the survivors were in NYHA class I-II.

CONCLUSIONS: Mitraclip therapy is a safe therapeutic option in selected high-risk patients with FMR, and it is associated with a lower hospital mortality and shorter length-of-stay compared with surgery, in spite of worse preoperative conditions. Early and 1-year rates of recurrent MR are higher with Mitraclip. Further studies are needed to determine the long-term clinical impact.