title: A novel approach to restore atrial function after the maze procedure in patients with an enlarged left atrium.
abstract: OBJECTIVE
  Left atrial (LA) volume reduction surgery concomitant with the maze procedure has been reported to facilitate sinus rhythm recovery even in patients with refractory atrial fibrillation (AF) with an enlarged LA. However, it is unknown whether the procedures can also restore effective atrial function of the enlarged LA with over-stretched myocardium.
  
  
  METHODS
  The maze procedures in association with mitral valve surgery were performed to 57 AF patients with an enlarged LA (LA diameter >or=60mm). Among them, 32 patients had concomitant LA volume reduction surgery (VR group). Another 25 patients did not have the volume reduction (control group).
  
  
  RESULTS
  Three months postoperatively LA end-diastolic volume (LAEDV, ml) assessed by magnetic resonance (MR) imaging was larger in the VR group than that in the control group (291+/-117 vs 223+/-81 ml, p<0.05). Postoperatively, sinus rhythm recovery rate was better (84 vs 68%, p<0.05) and LAEDV was drastically smaller (118+/-48 vs 203+/-76 ml, p<0.001) in the VR group than those in the control group. Among the patients with sinus rhythm recovery in both groups, LA contraction ejection fraction (%) improved in the VR group but not in the control group (22.3+/-7.8 vs 10.3+/-4.7%, p<0.001).
  
  
  CONCLUSIONS
  The LA volume reduction surgery concomitant with the maze procedure restored contraction of the enlarged LA; however, the maze procedure alone did not restore LA contraction in spite of successful sinus rhythm recovery. LA volume reduction surgery may be desirable to the patients with refractory AF with over-stretched LA.
authors.affiliation: Department of Cardiovascular Surgery, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Marui
authors.forename: Keiichi
authors.initials: K
authors.lastname: Tambara
authors.forename: Eiji
authors.initials: E
authors.lastname: Tadamura
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Saji
authors.forename: Nozomu
authors.initials: N
authors.lastname: Sasahashi
authors.forename: Tadashi
authors.initials: T
authors.lastname: Ikeda
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nishina
authors.forename: Masashi
authors.initials: M
authors.lastname: Komeda
mesh_terms: D001281:Atrial Fibrillation / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D016275:Atrial Function / Q000502:physiology*; D006348:Cardiac Surgical Procedures / Q000379:methods; D002908:Chronic Disease; D005260:Female; D006325:Heart Atria / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery; D006349:Heart Valve Diseases / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery; D009200:Myocardial Contraction / Q000502:physiology; D011182:Postoperative Care / Q000379:methods; D011300:Preoperative Care / Q000379:methods; D012189:Retrospective Studies; D016896:Treatment Outcome