title: Management and outcomes in patients with moderate or severe functional mitral regurgitation and severe left ventricular dysfunction.
abstract: OBJECTIVE
  The management and outcomes of patients with functional moderate/severe mitral regurgitation and severe left ventricular (LV) systolic dysfunction are not well defined. We sought to determine the characteristics, management strategies, and outcomes of patients with moderate or severe mitral regurgitation (MR) and LV systolic dysfunction.
  
  
  RESULTS
  For the period 1995-2010, the Duke Echocardiography Laboratory and Duke Databank for Cardiovascular Diseases databases were merged to identify patients with moderate or severe functional MR and severe LV dysfunction (defined as LV ejection fraction ≤ 30% or LV end-systolic diameter > 55 mm). We examined treatment effects in two ways. (i) A multivariable Cox proportional hazards model was used to assess the independent relationship of different treatment strategies and long-term event (death, LV assist device, or transplant)-free survival among those with and without coronary artery disease (CAD). (ii) To examine the association of mitral valve (MV) surgery with outcomes, we divided the entire cohort into two groups, those who underwent MV surgery and those who did not; we used inverse probability weighted (IPW) propensity adjustment to account for non-random treatment assignment. Among 1441 patients with moderate (70%) or severe (30%) MR, a significant history of hypertension (59%), diabetes (28%), symptomatic heart failure (83%), and CAD (52%) was observed. Past revascularization in 26% was noted. At 1 year, 1094 (75%) patients were treated medically. Percutaneous coronary intervention was performed in 114 patients, coronary artery bypass graft (CABG) surgery in 82, CABG and MV surgery in 96, and MV surgery alone in 55 patients. Among patients with CAD, compared with medical therapy alone, the treatment strategies of CABG surgery [hazard ratio (HR) 0.56, 95% confidence interval (CI) 0.42-0.76] and CABG with MV surgery (HR 0.58, 95% CI 0.44-0.78) were associated with long-term, event-free survival benefit. Percutaneous intervention treatment produced a borderline result (HR 0.78, 95% CI 0.61-1.00). However, the relationship with isolated MV surgery did not achieve statistical significance (HR 0.64, 95% CI 0.33-1.27, P = 0.202). Among those with CAD, following IPW adjustment, MV surgery was associated with a significant event-free survival benefit compared with patients without MV surgery (HR 0.71, 95% CI 0.52-0.95). In the entire cohort, following IPW adjustment, the use of MV surgery was associated with higher event-free survival (HR 0.69, 95% CI 0.53-0.88).
  
  
  CONCLUSIONS
  In patients with moderate or severe MR and severe LV dysfunction, mortality was substantial, and among those selected for surgery, MV surgery, though performed in a small number of patients, was independently associated with higher event-free survival.
authors.affiliation: Department of Medicine, Division of Cardiology, Duke Medicine, Durham, NC, USA zainab.samad@dm.duke.edu.
authors.forename: Zainab
authors.initials: Z
authors.lastname: Samad
authors.affiliation: Duke Clinical Research Institute, Duke Medicine, Durham, NC, USA.
authors.forename: Linda K
authors.initials: LK
authors.lastname: Shaw
authors.affiliation: Duke Clinical Research Institute, Duke Medicine, Durham, NC, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Phelan
authors.affiliation: Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Mads
authors.initials: M
authors.lastname: Ersboll
authors.affiliation: Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Niels
authors.initials: N
authors.lastname: Risum
authors.affiliation: Duke Clinical Research Institute, Duke Medicine, Durham, NC, USA.
authors.forename: Hussein R
authors.initials: HR
authors.lastname: Al-Khalidi
authors.affiliation: Department of Surgery, Duke Medicine, Durham, NC, USA.
authors.forename: Donald D
authors.initials: DD
authors.lastname: Glower
authors.affiliation: Department of Surgery, Duke Medicine, Durham, NC, USA.
authors.forename: Carmelo A
authors.initials: CA
authors.lastname: Milano
authors.affiliation: Department of Medicine, Division of Cardiology, Duke Medicine, Durham, NC, USA Duke Clinical Research Institute, Duke Medicine, Durham, NC, USA.
authors.forename: John H
authors.initials: JH
authors.lastname: Alexander
authors.affiliation: Department of Medicine, Division of Cardiology, Duke Medicine, Durham, NC, USA Duke Clinical Research Institute, Duke Medicine, Durham, NC, USA.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: O'Connor
authors.affiliation: Department of Medicine, Division of Cardiology, Duke Medicine, Durham, NC, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Wang
authors.affiliation: Department of Medicine, Division of Cardiology, Duke Medicine, Durham, NC, USA Duke Clinical Research Institute, Duke Medicine, Durham, NC, USA.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Velazquez
mesh_terms: D002316:Cardiotonic Agents / Q000627:therapeutic use; D001026:Coronary Artery Bypass / Q000401:mortality; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery; D008944:Mitral Valve Insufficiency / Q000150:complications / Q000401:mortality / Q000628:therapy*; D062645:Percutaneous Coronary Intervention / Q000401:mortality; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000401:mortality / Q000628:therapy*
chemical_list: D002316:Cardiotonic Agents
keywords: Left ventricular dysfunction; Mitral regurgitation; Mitral valve surgery; Outcomes