title: Incidence of late thromboembolic events after catheter ablation of atrial fibrillation.
abstract: BACKGROUND
  A low incidence of thromboembolic events after successful catheter ablation of atrial fibrillation (AF) during a mid-term follow-up period was recently reported. However, because the incidence of such events over the long term is unknown, we investigated the late incidence of thromboembolic events after catheter ablation.
  
  
  RESULTS
  Patients with paroxysmal and persistent AF undergoing catheter ablation and being followed up for at least 24 months formed the study group (n = 524); 82 patients (16%) had CHADS₂ scores of at least 2. Mean follow-up was 44 ± 13 months. Warfarin was discontinued in 400 (93%) of 429 patients (82% of 524 patients) without AF recurrence. None of the patients without AF recurrence suffered thromboembolic events, whereas 3 of 95 patients (3%) with AF recurrence did (P < 0.001). One of the 3 was a late AF recurrence occurring > 12 months after catheter ablation. There were 2 nonfatal major hemorrhagic events in patients with AF recurrence who continued on warfarin, but no hemorrhagic events were observed in patients free from AF (P = 0.002).
  
  
  CONCLUSIONS
  Maintenance of sinus rhythm after catheter ablation of AF was associated with a lower incidence of thromboembolic events during long-term follow-up >3 years. This result suggests that catheter ablation reduces thromboembolic events if patients continue anticoagulation regardless of the ablation outcome.
authors.affiliation: Department of Cardiovascular Medicine, Tokyo Medical and Dental University, Tokyo, Japan. atsuhikoyagishita@nifty.com
authors.forename: Atsuhiko
authors.initials: A
authors.lastname: Yagishita
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Takahashi
authors.forename: Akira
authors.initials: A
authors.lastname: Fujii
authors.forename: Shigeki
authors.initials: S
authors.lastname: Kusa
authors.forename: Tadashi
authors.initials: T
authors.lastname: Fujino
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Nozato
authors.forename: Taishi
authors.initials: T
authors.lastname: Kuwahara
authors.forename: Kenzo
authors.initials: K
authors.lastname: Hirao
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Isobe
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000150:complications* / Q000601:surgery; D017115:Catheter Ablation; D005260:Female; D005500:Follow-Up Studies; D006470:Hemorrhage; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D013923:Thromboembolism / Q000209:etiology* / Q000517:prevention & control; D014859:Warfarin / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D000925:Anticoagulants; D014859:Warfarin