title: Impact of Atrial Fibrillation Duration on the Success of First-Time Concomitant Cox Maze Procedures.
abstract: BACKGROUND
  Atrial fibrillation (AF) duration is one of the most consistent predictors of Cox maze (CM) procedure failure. We examined the impact of AF duration on CM success in patients having first-time concomitant surgery.
  
  
  METHODS
  First-time concomitant CM was performed in 505 patients. Freedom from atrial arrhythmia (AA) and class I/III antiarrhythmic drug (AAD) data were collected prospectively. Patients with longer AF duration (≥ 5 years; n = 113) were compared with shorter duration (<5 years; n = 392) in primary analyses. The AF duration was examined as a continuous variable in regression analyses.
  
  
  RESULTS
  Patients with longer AF duration were older (68.4 vs 65.1 years, p = 0.002) and in long-standing persistent AF (80% vs 36%, p < 0.001). Freedom from AA and AA off AAD was lower in longer duration patients at 1 year (80% vs 94%, p < 0.001; 74 vs 87%, p = 0.005) and 2 years (69 vs 90%, p < 0.001; 61 vs 81%, p = 0.001). Freedom from stroke or transient ischemic attack (TIA) was similar (96.1% vs 95.4%, p = 0.65). Adjusting for clinical and AF-associated factors, each 1-year increase in AF duration had 13% greater odds for failure at 1 year (odds ratio [OR], 1.13, p = 0.004) and 20% greater odds at 2 years (OR, 1.20, p < 0.001). Cryothermia as sole energy source attenuated the negative impact of AF duration on 1-year success.
  
  
  CONCLUSIONS
  Longer AF duration significantly impacted CM success and may result from extensive tissue remodeling. Patients with longer AF duration can expect reasonable success rates, especially when on AAD, and low stroke rates during follow-up. Cryoablation may reduce AF duration impact on success compared with combined bipolar radiofrequency and cryothermia.
authors.affiliation: Inova Heart and Vascular Institute, Falls Church, Virginia. Electronic address: niv.ad@inova.org.
authors.forename: Niv
authors.initials: N
authors.lastname: Ad
authors.affiliation: Inova Heart and Vascular Institute, Falls Church, Virginia.
authors.forename: Sari D
authors.initials: SD
authors.lastname: Holmes
authors.affiliation: Inova Heart and Vascular Institute, Falls Church, Virginia.
authors.forename: Deborah J
authors.initials: DJ
authors.lastname: Shuman
authors.affiliation: Inova Heart and Vascular Institute, Falls Church, Virginia.
authors.forename: Graciela
authors.initials: G
authors.lastname: Pritchard
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology* / Q000601:surgery; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D013997:Time Factors; D016896:Treatment Outcome