title: Effect of preoperative non-dialysis-dependent renal dysfunction on isolated aortic and mitral valve surgery: a propensity score analysis.
abstract: OBJECTIVE
  Our objective was to examine whether preoperative non-dialysis-dependent renal dysfunction is associated with operative mortality or morbidity in isolated valve surgery.
  
  
  METHODS
  We reviewed consecutive patients undergoing isolated aortic (n = 2132) or mitral valve (n = 1664) surgery, between 1996 and 2009. Preoperative renal dysfunction was defined as preoperative estimated glomerular filtration rate < 60 mL/min without dialysis. Propensity score 1:1 matched samples were created, one for aortic (n = 626) and one for mitral (n = 526) valve surgery.
  
  
  RESULTS
  The mean age was 70 ± 9 and 65 ± 10 years for the aortic and mitral groups, respectively. In the aortic cohort, patients with preoperative renal dysfunction had greater need for inotropes (39% vs 29%; P = .009), length of intensive care unit stay (27 vs 25 hours; P = .006), and duration of mechanical ventilation (8.2 vs 6.6 hours; P < .001). Operative mortality was 3.2% in the group with preoperative renal dysfunction and 2.2% in the group without preoperative renal dysfunction (P = .5). In the mitral cohort, patients with preoperative renal dysfunction had greater need for inotropes (47% vs 36%; P = .013), length of intensive care unit stay (40 vs 26 hours; P = .01), and duration of mechanical ventilation (7.2 vs 6.5 hours; P = .004). Operative mortality was 0% and 2.7% in the groups without and with preoperative renal dysfunction, respectively (P = .015).
  
  
  CONCLUSIONS
  Preoperative renal dysfunction is associated with higher morbidity in both cohorts, and patients undergoing mitral valve surgery also experienced higher mortality. The impact of non-dialysis-dependent preoperative renal dysfunction appears to be more pronounced in patients undergoing mitral valve surgery, potentially owing to their relative intolerance to volume overload.
authors.affiliation: Division of Cardiovascular Surgery, Peter Munk Cardiac Centre, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada.
authors.forename: Luis
authors.initials: L
authors.lastname: Garrido-Olivares
authors.forename: Tirone E
authors.initials: TE
authors.lastname: David
authors.forename: Manjula
authors.initials: M
authors.lastname: Maganti
authors.forename: Duminda
authors.initials: D
authors.lastname: Wijeysundera
authors.forename: Vivek
authors.initials: V
authors.lastname: Rao
mesh_terms: D000368:Aged; D001021:Aortic Valve / Q000601:surgery*; D006348:Cardiac Surgical Procedures / Q000009:adverse effects / Q000401:mortality; D002316:Cardiotonic Agents / Q000627:therapeutic use; D016009:Chi-Square Distribution; D005260:Female; D005919:Glomerular Filtration Rate; D006349:Heart Valve Diseases / Q000150:complications / Q000401:mortality / Q000601:surgery*; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D007668:Kidney / Q000503:physiopathology*; D007674:Kidney Diseases / Q000150:complications* / Q000401:mortality / Q000503:physiopathology; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery*; D009864:Ontario; D057216:Propensity Score; D012121:Respiration, Artificial; D018570:Risk Assessment; D012307:Risk Factors; D016896:Treatment Outcome
chemical_list: D002316:Cardiotonic Agents