title: Maze procedure in patients with left ventricular dysfunction.
abstract: BACKGROUND
  The risks and benefits of a concomitant Maze procedure for patients with LV dysfunction undergoing major cardiac surgery have not yet been elucidated. This study aimed to evaluate the clinical impacts of the Maze procedure in patients with atrial fibrillation and left ventricular (LV) dysfunction.
  
  
  METHODS
  Between January 1999 and March 2011, a total of 139 patients (mean age 52.7±12.3 years, 54 females) with valvular atrial fibrillation (AF) and an LV ejection fraction (EF) of 40% or less underwent open heart surgery with (n=77) or without (n=62) a concomitant Maze procedure. We compared adverse outcomes (death and composite of death, thromboembolic events and congestive heart failure [CHF]) during a median follow-up period of 66.0 months (inter-quartile range, 27.5-106.9 months).
  
  
  RESULTS
  Adverse events occurred in 41 patients, including 36 deaths, seven thromboembolic events and eight hospitalizations due to CHF. After adjustment for baseline profiles with the use of propensity scores and inverse probability weighting, patients who had the Maze procedure were at lower risks of death (hazard ratio, 0.39; 95% confidence interval, 0.16-0.93; P=0.033) and composite adverse outcomes (hazard ratio, 0.28; 95% confidence interval, 0.14-0.57; P=0.017) than those not undergoing the Maze procedure. Furthermore, the Maze procedure resulted in superior functional status (P<0.001) and reduced the need for long-term anticoagulation therapy (67.1% vs. 91.2%, P=0.001).
  
  
  CONCLUSIONS
  Performing the Maze procedure on patients with valvular AF and LV dysfunction reduced serious adverse outcomes and the need for long-term anticoagulation therapy when compared to cardiac surgery alone without the Maze procedure.
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors.forename: Joon Bum
authors.initials: JB
authors.lastname: Kim
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors.forename: Byung Kwon
authors.initials: BK
authors.lastname: Chong
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors.forename: Sung-Ho
authors.initials: SH
authors.lastname: Jung
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors.forename: Suk Jung
authors.initials: SJ
authors.lastname: Choo
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors.forename: Cheol Hyun
authors.initials: CH
authors.lastname: Chung
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea. Electronic address: jwlee@amc.seoul.kr.
authors.forename: Jae Won
authors.initials: JW
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000401:mortality* / Q000601:surgery*; D006348:Cardiac Surgical Procedures / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D016208:Databases, Factual / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000209:etiology / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D013923:Thromboembolism / Q000209:etiology / Q000401:mortality / Q000517:prevention & control; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000401:mortality* / Q000601:surgery*
chemical_list: D000925:Anticoagulants
keywords: Ablation; Atrial fibrillation; Heart failure; Surgery; Survival