title: Ischemic versus degenerative mitral regurgitation: does etiology affect survival?
abstract: BACKGROUND
  Ischemic mitral regurgitation (MR) is associated with poor survival and degenerative MR with excellent survival. We hypothesized that in some patients with degenerative MR requiring concomitant coronary artery bypass grafting (CABG), ischemic disease would dominate prognosis, resulting in survival as poor as in patients with ischemic MR. Thus, we (1) determined survival impact of etiology (degenerative vs ischemic) after combined mitral valve repair and CABG and (2) explored survival differences within etiology groups.
  
  
  METHODS
  From 1985 to 2003, 710 patients underwent mitral valve repair for degenerative MR and concomitant CABG (two diseases); 400 patients had mitral annuloplasty and CABG for functional ischemic MR (one disease). Patients were propensity-matched on demography, symptoms, comorbidities, coronary artery disease, and left ventricular function. Survival was compared between matched groups and within groups.
  
  
  RESULTS
  Compared with patients with degenerative MR, those with ischemic MR had more extensive coronary artery disease, worse ventricular function, more comorbidities, and more symptoms (p < 0.05). Unadjusted 5-year survivals were 64% and 82% for patients with ischemic and degenerative MR, respectively. However, 123 ischemic and degenerative MR matched pairs had equivalently poor 5-year survival (p > 0.9), 66% and 65%, respectively. Among patients with degenerative MR, survival varied widely, depending largely on ischemic burden and extent of left ventricular dysfunction.
  
  
  CONCLUSIONS
  The large survival discrepancy between patients with ischemic and degenerative MR is attributable to differences in patient profile, particularly extent of ischemic disease and left ventricular dysfunction. Thus, ischemic and degenerative MR patients with equivalent characteristics have equivalently poor survival.
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA. gillinom@ccf.org
authors.forename: A Marc
authors.initials: AM
authors.lastname: Gillinov
authors.forename: Eugene H
authors.initials: EH
authors.lastname: Blackstone
authors.forename: Jeevanantham
authors.initials: J
authors.lastname: Rajeswaran
authors.forename: Maurice
authors.initials: M
authors.lastname: Mawad
authors.forename: Patrick M
authors.initials: PM
authors.lastname: McCarthy
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Sabik
authors.forename: Takahiro
authors.initials: T
authors.lastname: Shiota
authors.forename: Bruce W
authors.initials: BW
authors.lastname: Lytle
authors.forename: Delos M
authors.initials: DM
authors.lastname: Cosgrove
mesh_terms: D000368:Aged; D009202:Cardiomyopathies / Q000453:epidemiology; D015984:Causality; D015897:Comorbidity; D001026:Coronary Artery Bypass / Q000401:mortality; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008944:Mitral Valve Insufficiency / Q000145:classification* / Q000401:mortality* / Q000601:surgery; D017202:Myocardial Ischemia / Q000453:epidemiology; D009820:Ohio / Q000453:epidemiology; D012044:Regression Analysis; D016019:Survival Analysis