Percutaneous Mitral Valve Repair for Secondary Mitral Regurgitation: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to investigate whether percutaneous mitral valve repair (PMVr) using MitraClip was more effective than surgery or medical therapy for long-term morbidity and mortality. We searched MEDLINE, EMBASE, and CENTRAL (Cochrane Library) databases to identify relevant studies that recruited adult patients with functional or secondary mitral valve regurgitation who underwent PMVr with MitraClip implantation using appropriate search terms and Boolean operators. The odds ratios (ORs) were pooled using the random-effects model. A total of 14 studies recruiting 2,593 patients were included. Within 12 months of follow-up, patients who underwent PMVr did not maintain mitral valve regurgitation grade 2+ (OR 0.22, 95% confidence interval [CI] 0.12 to 0.41, p <0.0001, I² = 0.0%, p = 0.52) or symptom-free heart failure (OR 0.47, 95% CI 0.29 to 0.77, p = 0.0028, I² = 0.0%, p = 0.66) compared with their surgical counterparts. Patients were more likely to be rehospitalized for heart failure (OR 2.79, 95% CI 1.54 to 5.05, p = 0.0007, I² = 0.0%, p = 0.51). However, there was no difference between the groups in terms of all-cause or cardiovascular mortality. Whereas, in comparison with medical therapy, PMVr significantly reduced all-cause mortality at 12 and ≥24 months of follow-up (OR 0.41, 95% CI 0.24, 0.69, p = 0.0009, I² = 32%, p = 0.23 and OR 0.55, 95% CI 0.40, 0.75, p = 0.0002, I² = 0.0%, p = 0.45, respectively). In conclusion, there was no difference in all-cause death at 12 or 24 months of follow-up between PMVr and the surgical approach, but the durability of valvular repair was inferior with PMVr. In comparison with medical therapy, there was a significant reduction in mortality with PMVr.