title: Modified maze during endoscopic mitral valve surgery: the OLV Clinic experience.
abstract: BACKGROUND
  The use of radiofrequency ablation to perform the mini-maze procedure (pulmonary veins isolation) has been reported with good results. The aim of this study was to evaluate our practice with the association of the mini-maze procedure, done with the use of the Cardioblade pen, and minimally invasive mitral valve surgery.
  
  
  METHODS
  From January 1999 to November 2004, 103 patients underwent a minimally invasive mitral valve surgery with a concomitant pulmonary veins isolation (modified maze procedure) done with unipolar radiofrequency. All files were reviewed retrospectively.
  
  
  RESULTS
  In our group of patients, 41.2% were known to have intermittent atrial fibrillation and 58.8%, continuous atrial fibrillation; 67.7% of the patients were in atrial fibrillation at the time of surgery. Precise time of duration of atrial fibrillation was known in 47.6% (mean time, 30.3 +/- 28.9 months), but 47.7% were also known to have atrial fibrillation for many years. Mitral surgery included mitral valve repair in 71.8% and mitral valve replacement in 26.2%; 22 patients also received tricuspid annuloplasty. Major complications were mortality in 1%, myocardial infarction in 1%, stroke or transient ischemic attack in 1.9% and permanent pacemaker placement in 5.9%. At the time of discharge, 71.9% of patients were in sinus rhythm, 21.9% in atrial fibrillation, 1% in atrial flutter, and 5.2% in paced rhythm. Seventy-six and a half percent of the patients left the hospital with an antiarrhythmic drug (amiodarone 56.9%, sotalol 15.7%). At the time of follow-up, 99 patients were still alive with a mean follow-up time of 17.4 +/- 14.1 months; 69.7% of patients were in sinus rhythm, 28.3% in atrial fibrillation, and 2% were pacemaker-dependent. Patients received antiarrhythmic medication in 81.2% of cases (amiodarone 46.4%, sotalol 17.9%, beta-blocker 39.3%, digoxine 7.1%). Eleven new pacemakers were implanted (11.1%).
  
  
  CONCLUSIONS
  The use of unipolar radiofrequency ablation to perform a mini-maze during minimally invasive mitral valve surgery is a safe procedure and is associated with good early results.
authors.affiliation: Department of Cardiovascular and Thoracic Surgery, OLV Clinic, Aalst, Belgium.
authors.forename: Hugues
authors.initials: H
authors.lastname: Jeanmart
authors.forename: Filip
authors.initials: F
authors.lastname: Casselman
authors.forename: Roel
authors.initials: R
authors.lastname: Beelen
authors.forename: Francis
authors.initials: F
authors.lastname: Wellens
authors.forename: Ihsan
authors.initials: I
authors.lastname: Bakir
authors.forename: F
authors.initials: F
authors.lastname: Van Praet
authors.forename: Guy
authors.initials: G
authors.lastname: Cammu
authors.forename: Yvan
authors.initials: Y
authors.lastname: Degriek
authors.forename: Yvette
authors.initials: Y
authors.lastname: Vermeulen
authors.forename: Hugo
authors.initials: H
authors.lastname: Vanermen
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications / Q000601:surgery*; D006348:Cardiac Surgical Procedures; D017115:Catheter Ablation; D005260:Female; D006349:Heart Valve Diseases / Q000150:complications / Q000601:surgery*; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures; D008943:Mitral Valve / Q000601:surgery*; D011667:Pulmonary Veins / Q000601:surgery; D012189:Retrospective Studies; D016896:Treatment Outcome; D014261:Tricuspid Valve / Q000601:surgery