title: Long-term changes in heart rate variability after radiofrequency catheter ablation for atrial fibrillation: 1-year follow-up study with irrigation tip catheter.
abstract: BACKGROUND
  Radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) changes cardiac autonomic nerve activity. However, the long-term effect of RFCA has not yet been evaluated when an open irrigation tip catheter (OITC) was used. Therefore, we hypothesized that AF ablation changes heart rate variability (HRV) that would be maintained over 1 year after OITC ablation and be associated with clinical recurrence of AF.
  
  
  RESULTS
  We analyzed pre-RFCA HRV (HRVpre ), HRV at 3 months (HRV3mo ) and 1 year (HRV1yr ) after RFCA using 24-hour Holter monitoring after excluding arrhythmic events in 144 patients (70% male, 57 ± 10 years old, 83% paroxysmal AF) who underwent RFCA with OITC. After RFCA with OITC, the increase in mean heart rate and the reduction in HF or LF/HF were significant at HRV3mo (P < 0.001) and were maintained at HRV1yr (P < 0.001). During 20 ± 8 months of follow-up, 33 of 144 patients (23%) showed clinical recurrence of AF. Patients in the nonrecurrence group showed significant reductions of rMSSD and HF at HRV3mo and HRV1yr , but patients with clinical recurrence did not. In Cox regression analysis, a reduction in LF/HF (ΔLF/HF) ≥0.26 at HRV3mo was significantly associated with clinical recurrence of AF (hazard ratio 2.52, 95% CI 1.19-5.32, P = 0.015).
  
  
  CONCLUSIONS
  In contrast to previous reports about long-term HRV recovery after AF ablation with a conventional catheter, change in cardiac autonomic nervous activity was maintained for 1 year after RFCA when an OITC was used. A reduction in ΔLF/HF ≥0.26 at HRV3mo was independently associated with clinical recurrence of AF after RFCA.
authors.affiliation: Eulji University Hospital, Daejeon, Republic of Korea.
authors.forename: Ki-Woon
authors.initials: KW
authors.lastname: Kang
authors.forename: Tae Hoon
authors.initials: TH
authors.lastname: Kim
authors.forename: Junebom
authors.initials: J
authors.lastname: Park
authors.forename: Jae Sun
authors.initials: JS
authors.lastname: Uhm
authors.forename: Boyoung
authors.initials: B
authors.lastname: Joung
authors.forename: Chun
authors.initials: C
authors.lastname: Hwang
authors.forename: Moon-Hyung
authors.initials: MH
authors.lastname: Lee
authors.forename: Hui-Nam
authors.initials: HN
authors.lastname: Pak
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D001341:Autonomic Nervous System / Q000503:physiopathology; D006328:Cardiac Catheterization / Q000295:instrumentation*; D062906:Cardiac Catheters; D017115:Catheter Ablation / Q000295:instrumentation*; D016009:Chi-Square Distribution; D015716:Electrocardiography, Ambulatory; D004867:Equipment Design; D005260:Female; D006339:Heart Rate; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D012008:Recurrence; D012307:Risk Factors; D007507:Therapeutic Irrigation / Q000295:instrumentation*; D013997:Time Factors; D016896:Treatment Outcome
keywords: atrial fibrillation; catheter ablation; heart rate variability; irrigation tip catheter