title: Difference of clinical course after catheter ablation of atrioventricular nodal reentrant tachycardia between younger and older patients: atrial vulnerability predicts new onset of atrial fibrillation.
abstract: BACKGROUND
  The aim of this study was to compare the long-term procedural outcomes, the stability of atrioventricular conduction, and the new onset of atrial fibrillation (AF), after ablation of atrioventricular nodal reentrant tachycardia (AVNRT).
  
  
  RESULTS
  Consecutive patients with AVNRT (n=109), who underwent slow-pathway ablation, were divided into two groups based on the median age of the studied patients: the younger group aged <55 years and the older group aged ≥55 years. During a mean follow-up period of 60.6 months, the rate of change in the PR interval from before ablation to follow-up was significantly greater in older patients compared with younger patients. However, there was no delayed-onset high-degree AV block during follow-up in either group. No patients in the younger group suffered from persistent AF, whereas persistent AF occurred in 5/54 (9.3%) older patients. Multivariate Cox analysis revealed that atrial vulnerability, with induction of AF during the electrophysiological study, was the only predictor of the development of AF (Hazard ratio: 13.9, 95% confidence interval: 1.62-119.2, p<0.01).
  
  
  CONCLUSIONS
  Slow-pathway ablation of AVNRT is a reliable strategy even in older patients. However, physicians should consider regular long-term follow-up of older patients with atrial vulnerability, in order to assess the subsequent development of AF.
authors.affiliation: Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Japan. t-arimoto@med.id.yamagata-u.ac.jp
authors.forename: Takanori
authors.initials: T
authors.lastname: Arimoto
authors.forename: Tetsu
authors.initials: T
authors.lastname: Watanabe
authors.forename: Joji
authors.initials: J
authors.lastname: Nitobe
authors.forename: Tadateru
authors.initials: T
authors.lastname: Iwayama
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kutsuzawa
authors.forename: Takuya
authors.initials: T
authors.lastname: Miyamoto
authors.forename: Takehiko
authors.initials: T
authors.lastname: Miyashita
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Shishido
authors.forename: Hiroki
authors.initials: H
authors.lastname: Takahashi
authors.forename: Naoki
authors.initials: N
authors.lastname: Nozaki
authors.forename: Akio
authors.initials: A
authors.lastname: Fukui
authors.forename: Isao
authors.initials: I
authors.lastname: Kubota
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D017115:Catheter Ablation / Q000009:adverse effects / Q000639:trends*; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012307:Risk Factors; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000453:epidemiology* / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors; D055815:Young Adult