title: The closed heart MAZE: a nonbypass surgical technique.
abstract: BACKGROUND
  The MAZE-III is the surgical treatment of choice for medically refractory atrial fibrillation. Although a number of nonsurgical techniques are evolving to duplicate the transmural atrial lesions of the MAZE-III, the surgical atriotomy remains the gold standard for conduction block. It was the objective of this study to surgically create the atrial incisions of the MAZE-III without the use of cardiopulmonary bypass.
  
  
  METHODS
  A technique was developed to create and intersect the linear incisions of the MAZE-III on 10 beating canine hearts without the use of cardiopulmonary bypass using a "tunnel" of atrial tissue. The effectiveness of the procedure was tested by atrial burst pacing.
  
  
  RESULTS
  This technique was successfully performed on 10 mongrel dogs without operative mortality. Preoperatively, sustained atrial fibrillation (>30 seconds) was induced in all animals. Postoperatively, all the animals remained in sinus rhythm even after burst pacing.
  
  
  CONCLUSIONS
  In an experimental canine model, the MAZE-III can be performed on beating hearts without the assistance of cardiopulmonary bypass using a "tunnel" technique. This technique allows for the immediate assessment of electrophysiologic and mechanical function after the MAZE-III, or any other type of procedure using the "maze principle" and may find future application in the clinical arena.
authors.affiliation: Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
authors.forename: R
authors.initials: R
authors.lastname: Lee
authors.forename: T
authors.initials: T
authors.lastname: Nitta
authors.forename: R B
authors.initials: RB
authors.lastname: Schuessler
authors.forename: D C
authors.initials: DC
authors.lastname: Johnson
authors.forename: J P
authors.initials: JP
authors.lastname: Boineau
authors.forename: J L
authors.initials: JL
authors.lastname: Cox
mesh_terms: D000818:Animals; D001281:Atrial Fibrillation / Q000601:surgery*; D006348:Cardiac Surgical Procedures / Q000379:methods*; D004285:Dogs; D005240:Feasibility Studies; D006488:Hemostasis, Surgical; D013536:Suture Techniques