title: A review of comparative studies of MitraClip versus surgical repair for mitral regurgitation.
abstract: OBJECTIVE
  We summarized comparative studies of MitraClip versus surgical repair for mitral regurgitation (MR) with a systematic literature search and meta-analytic estimates.
  
  
  METHODS
  MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched through June 2016. Eligible studies were randomized controlled or observational comparative studies of MitraClip versus surgical repair enrolling patients with MR and reporting early (30-day or in-hospital) or late (≥6-month including early) all-cause mortality. For each study, data regarding all-cause mortality and incidence of recurrent >2+ MR in both groups were used to generate odds ratios (ORs). Alternatively, ORs or hazard ratios (HRs) for mortality and recurrent MR themselves were directly abstracted from each study.
  
  
  RESULTS
  Eight reports of 7 studies comparing MitraClip with surgical repair enrolling a total of 1015 patients with MR were identified and included. Pooled analyses demonstrated significantly higher age and logistic European System of Cardiac Operative Risk Evaluation and significantly lower ejection fraction in the MitraClip than surgical repair group, no significant difference in rate of women and patients with New York Heart Association functional class of >II, no statistically significant difference in early- (OR, 0.54; p=0.08) and late-mortality (HR/OR, 1.17; p=0.46), and significantly higher incidence of recurrent MR in the MitraClip than surgical repair group (HR/OR, 4.80; p<0.00001).
  
  
  CONCLUSIONS
  In patients with MR, the MitraClip procedure achieves similar survival to surgical MV repair despite higher risk profiles. Recurrent MR, however, occurs more frequently (4.8-fold) after the MitraClip than surgical repair.
authors.affiliation: Department of Cardiovascular Surgery, Shizuoka Medical Center, Shizuoka, Japan. Electronic address: kfgth973@ybb.ne.jp.
authors.forename: Hisato
authors.initials: H
authors.lastname: Takagi
authors.affiliation: Department of Cardiology, Detroit Medical Center, Detroit, MI, United States.
authors.forename: Tomo
authors.initials: T
authors.lastname: Ando
authors.affiliation: Department of Cardiovascular Surgery, Shizuoka Medical Center, Shizuoka, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Umemoto
mesh_terms: D002423:Cause of Death; D005260:Female; D019918:Heart Valve Prosthesis Implantation / Q000379:methods* / Q000401:mortality; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D019060:Minimally Invasive Surgical Procedures / Q000379:methods / Q000401:mortality; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery*; D016017:Odds Ratio; D011379:Prognosis; D016016:Proportional Hazards Models; D016032:Randomized Controlled Trials as Topic; D018570:Risk Assessment; D012720:Severity of Illness Index; D013525:Surgical Instruments; D016019:Survival Analysis; D016896:Treatment Outcome
keywords: Meta-analysis; MitraClip; Mitral regurgitation; Mitral repair