title: A novel atrial volume reduction technique to enhance the Cox maze procedure: initial results.
abstract: OBJECTIVE
  Large left atrial diameter is reported to be a predictor for recurrent atrial fibrillation after the Cox maze procedure, and left atrial diameter by itself influences the chance of sinus rhythm recovery, as well as maintenance of sinus rhythm. However, additional cut-and-sew procedures to decrease left atrial diameter extend operative time and can cause bleeding. Thus we developed a no-bleeding, faster, and therefore less invasive left atrial volume reduction technique to enhance the Cox maze procedure.
  
  
  METHODS
  The modified Cox maze III procedure with cryoablation or the left atrial maze procedure in association with mitral valve surgery was performed in 80 patients with atrial fibrillation and enlarged left atria (> or =60 mm). Among them, 44 patients had the concomitant volume reduction technique (VR group); continuous horizontal mattress sutures for left atrial plication were placed on the left atrial wall along the pulmonary vein isolation line. Cryoablation was applied to the suture line so that the plicated left atrium is anatomically and electrically isolated. Another 36 patients did not have the volume reduction technique (control group).
  
  
  RESULTS
  The VR group had preoperative left atrial diameters similar to those of the control group (67.1 +/- 7.8 vs 64.5 +/- 6.7 mm) and a longer preoperative duration of atrial fibrillation (14.1 +/- 5.4 vs 9.5 +/- 5.1 years, P < .05) but had smaller postoperative left atrial diameters (47.6 +/- 6.3 vs 62.1 +/- 7.9 mm, P < .01). There were no differences in mean crossclamp/bypass time and chest tube drainage for 12 hours between the groups. Twelve months after surgical intervention, the sinus rhythm recovery rate of the VR group was better than that of the control group (90% vs 69%, P < .05).
  
  
  CONCLUSIONS
  Even in patients with long-standing atrial fibrillation and an enlarged left atrium, maze procedures concomitant with the novel left atrial volume reduction technique improved the sinus rhythm recovery rate without increasing complications. Although further study with a larger number of patients and a longer follow-up period is needed, this safe and thus far potent technique that catheter-based ablation cannot copy might extend indication of the Cox maze procedure for patients with tough atrial fibrillation.
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: Takeshi
authors.initials: T
authors.lastname: Nishina
authors.forename: Keiichi
authors.initials: K
authors.lastname: Tambara
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Saji
authors.forename: Takeshi
authors.initials: T
authors.lastname: Shimamoto
authors.forename: Masahiko
authors.initials: M
authors.lastname: Nishioka
authors.forename: Tadashi
authors.initials: T
authors.lastname: Ikeda
authors.forename: Masashi
authors.initials: M
authors.lastname: Komeda
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications / Q000601:surgery*; D006348:Cardiac Surgical Procedures / Q000379:methods*; D002908:Chronic Disease; D003452:Cryosurgery; D005260:Female; D006325:Heart Atria / Q000601:surgery*; D006331:Heart Diseases / Q000601:surgery; D006349:Heart Valve Diseases / Q000150:complications / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery; D012008:Recurrence