title: Electrophysiologic Results After Thoracoscopic Ablation for Chronic Atrial Fibrillation.
abstract: BACKGROUND
  Thoracoscopic ablation for lone atrial fibrillation (AF) has evolved rapidly in the past decade. We investigated the electrophysiologic results and midterm durability of totally thoracoscopic ablation in patients with lone persistent AF.
  
  
  METHODS
  Seventy-nine consecutive patients with paroxysmal AF (8 patients, 10.1%), persistent AF (17 patients, 21.5%), and long-standing persistent AF (54 patients, 68.3%) were prospectively enrolled. Thoracoscopic ablation consisted of a bilateral closed-chest approach to performing pulmonary isolation (a box lesion), ganglionated plexus ablation, division of the Marshall ligament, and left atrial auricle resection. An electrophysiologic study was performed 5 days after the surgical procedure in 61 patients (77%). Freedom from AF was assessed with electrocardiograms or Holter monitoring every 3 months, with a mean follow-up of 12.1 (maximum, 28) months.
  
  
  RESULTS
  No deaths or conversion to cardiopulmonary bypass occurred. During electrophysiologic study, 28 residual pulmonary vein potentials were observed in 15 patients (19%). Out of a total of 28 gaps, 20 (71%) were located in the superior and inferior ridges of pulmonary veins. Six gaps (21%) were detected in the carina of pulmonary veins. The mitral isthmus was ablated in 2 patients (7%). Freedom from AF at 2 years was 92.6 ± 3.3%. Freedom from cardiac-related events at 2 years was 74.7 ± 6.0%. Cox regression analysis demonstrated that the predictors of atrial arrhythmias were old age, hypertension, and left atrial volume index.
  
  
  CONCLUSIONS
  Thoracoscopic ablation followed by electrophysiologic confirmation was safe and provided excellent midterm durability in patients with AF. However, the incidence of residual potentials around the pulmonary veins was not negligible.
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Young Keun
authors.initials: YK
authors.lastname: On
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kyoung-Min
authors.initials: KM
authors.lastname: Park
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Heart Stroke Vascular Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. Electronic address: opheart1@gmail.com.
authors.forename: Dong Seop
authors.initials: DS
authors.lastname: Jeong
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Heart Stroke Vascular Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Pyo Won
authors.initials: PW
authors.lastname: Park
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Heart Stroke Vascular Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Young Tak
authors.initials: YT
authors.lastname: Lee
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Seung-Jung
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: June Soo
authors.initials: JS
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D002908:Chronic Disease; D015716:Electrocardiography, Ambulatory / Q000379:methods*; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D012189:Retrospective Studies; D020775:Thoracic Surgery, Video-Assisted / Q000379:methods*; D013997:Time Factors; D016896:Treatment Outcome