title: Designing comparative effectiveness trials of surgical ablation for atrial fibrillation: experience of the Cardiothoracic Surgical Trials Network.
abstract: OBJECTIVE
  Since the introduction of the cut-and-sew Cox maze procedure for atrial fibrillation, there has been substantial innovation in techniques for ablation. Use of alternative energy sources for ablation simplified the procedure and has resulted in dramatic increase in the number of patients with atrial fibrillation treated by surgical ablation. Despite its increasingly widespread adoption, there is lack of rigorous clinical evidence to establish this procedure as an effective clinical therapy.
  
  
  METHODS
  This article describes a comparative effectiveness randomized trial, supported by the Cardiothoracic Surgical Clinical Trials Network, of surgical ablation with left atrial appendage closure versus left atrial appendage closure alone in patients with persistent and long-standing persistent atrial fibrillation undergoing mitral valve surgery. Nested within this trial is a further randomized comparison of 2 different lesions sets: pulmonary vein isolation and the full maze lesion set.
  
  
  RESULTS
  This article addresses trial design challenges, including how best to characterize the target population, operationalize freedom from atrial fibrillation as a primary end point, account for the impact of antiarrhythmic drugs, and measure and analyze secondary end points, such as postoperative atrial fibrillation load.
  
  
  CONCLUSIONS
  This article concludes by discussing how insights that emerge from this trial may affect surgical practice and guide future research in this area.
authors: Department of Thoracic and Cardiovascular Surgery, Cleveland Clinic, Cleveland, Ohio, USA.
authors: A Marc
authors: AM
authors: Gillinov
authors: Michael
authors: M
authors: Argenziano
authors: Eugene H
authors: EH
authors: Blackstone
authors: Alexander
authors: A
authors: Iribarne
authors: Joseph J
authors: JJ
authors: DeRose
authors: Gorav
authors: G
authors: Ailawadi
authors: Mark J
authors: MJ
authors: Russo
authors: Deborah D
authors: DD
authors: Ascheim
authors: Michael K
authors: MK
authors: Parides
authors: Evelio
authors: E
authors: Rodriguez
authors: Denis
authors: D
authors: Bouchard
authors: Wendy C
authors: WC
authors: Taddei-Peters
authors: Nancy L
authors: NL
authors: Geller
authors: Michael A
authors: MA
authors: Acker
authors: Annetine C
authors: AC
authors: Gelijns
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