title: Staged transthoracic approach to persistent atrial fibrillation (TOP-AF): study protocol for a randomized trial.
abstract: BACKGROUND
  Persistent atrial fibrillation frequently shows multiple different electrophysiological mechanisms of induction. This heterogeneity causes a low success rate of single procedures of ablation and a high incidence of recurrence. Surgical ablation through bilateral thoracotomy demonstrates better results after a single procedure. Prospective observational studies in inhomogeneous populations without control groups report a remarkable 90% of success with hybrid or staged procedures of surgical ablation coupled with catheter ablation. In this trial, we will examine the hypothesis that a staged approach involving initial minimally invasive surgical ablation of persistent atrial fibrillation, followed by a second percutaneous procedure in case of recurrence, has a higher success rate than repeated percutaneous procedures.
  
  
  METHODS
  This is a controlled (2:1) randomized trial comparing use of a percutaneous catheter with minimally invasive transthoracic surgical ablation of persistent atrial fibrillation. The inclusion and exclusion criteria, definitions, and treatment protocols are those reported by the 2012 Expert Consensus Statement on catheter and surgical ablation of atrial fibrillation. Patients will be randomized to either percutaneous catheter (n = 100) or surgical (n = 50) ablation as the first procedure. After 3 months, they are re-evaluated, according to the same guidelines, and receive a second procedure if necessary. Crossover will be allowed and data analyzed on an "intention-to-treat" basis. Primary outcomes are the incidence of sinus rhythm at 6 and 12 months and the proportions of patients requiring a second procedure.
  
  
  CONCLUSIONS
  The use of a staged strategy combining surgical and percutaneous approaches might be more favorable in treatment of persistent atrial fibrillation than the controversial single percutaneous ablation.
  
  
  BACKGROUND
  ISRCTN08035058 Reg 06.20.2013.
authors.affiliation: Dipartimento di Scienze Cardiovascolari, Policlinico A Gemelli, Largo Gemelli 8, 00168 Roma, Italy. claudio.pragliola@libero.it.
authors.forename: Claudio
authors.initials: C
authors.lastname: Pragliola
authors.forename: Pasquale
authors.initials: P
authors.lastname: Mastroroberto
authors.forename: Mario
authors.initials: M
authors.lastname: Gaudino
authors.forename: Massimo
authors.initials: M
authors.lastname: Chello
authors.forename: Elvio
authors.initials: E
authors.lastname: Covino
mesh_terms: D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D000925:Anticoagulants / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000188:drug therapy / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D006801:Humans; D019060:Minimally Invasive Surgical Procedures / Q000379:methods*; D012008:Recurrence; D012086:Reoperation / Q000379:methods; D012107:Research Design; D013908:Thoracotomy / Q000379:methods*
chemical_list: D000889:Anti-Arrhythmia Agents; D000925:Anticoagulants