title: Prolonged PR interval predicts clinical recurrence of atrial fibrillation after catheter ablation.
abstract: BACKGROUND
  A prolonged PR interval is known to be a poor prognostic factor in cardiovascular disease. The aim of this study was to investigate the association between PR interval and clinical outcome in patients undergoing radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF).
  
  
  RESULTS
  We prospectively included 576 patients with AF (75.5% male, 57.8±11.6 years old, 68.8% paroxysmal AF) who underwent RFCA. We analyzed preprocedural sinus rhythm ECGs obtained in the absence of antiarrhythmic drug, and all enrolled patients were categorized into 4 groups based on the quartile values of the PR interval (166, 182, and 202 ms), and were analyzed according to the left atrium (LA) volume (CT; Computed tomography), LA voltage (NavX), and clinical outcome of AF ablation. Based on quartile value of PR interval, the highest quartile of PR interval (Q4; PR ≥202 ms) was oldest (P<0.001), and most likely to have persistent AF (P<0.001) and hypertension (P=0.013) compared with the other groups. However, there was no significant difference in LA conduction velocity and atrial effective refractory period. Q4 had the greatest LA dimension (P<0.001) and volume index (P<0.001), and lowest LA appendage-emptying velocity (P<0.032) and LA voltage (P<0.001) compared with the others. For 13.1±7.5 months, the classification based on the PR interval was a significant predictor of AF recurrence after RFCA of AF (HR=1.969, 95% CI 1.343 to 2.886, P=0.001).
  
  
  CONCLUSIONS
  The PR interval was closely associated with advanced LA remodeling due to AF, and had a noninvasive significant predictive value of clinical recurrence of AF after RFCA.
authors.affiliation: Yonsei University Health System, Seoul, Korea (J.P., T.H.K., J.S.L., J.K.P., J.S.U., B.J., M.H.L., H.N.P.).
authors.forename: Junbeom
authors.initials: J
authors.lastname: Park
authors.affiliation: Yonsei University Health System, Seoul, Korea (J.P., T.H.K., J.S.L., J.K.P., J.S.U., B.J., M.H.L., H.N.P.).
authors.forename: Tae-Hoon
authors.initials: TH
authors.lastname: Kim
authors.affiliation: Yonsei University Health System, Seoul, Korea (J.P., T.H.K., J.S.L., J.K.P., J.S.U., B.J., M.H.L., H.N.P.).
authors.forename: Jihei Sara
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Yonsei University Health System, Seoul, Korea (J.P., T.H.K., J.S.L., J.K.P., J.S.U., B.J., M.H.L., H.N.P.).
authors.forename: Jin Kyu
authors.initials: JK
authors.lastname: Park
authors.affiliation: Yonsei University Health System, Seoul, Korea (J.P., T.H.K., J.S.L., J.K.P., J.S.U., B.J., M.H.L., H.N.P.).
authors.forename: Jae Sun
authors.initials: JS
authors.lastname: Uhm
authors.affiliation: Yonsei University Health System, Seoul, Korea (J.P., T.H.K., J.S.L., J.K.P., J.S.U., B.J., M.H.L., H.N.P.).
authors.forename: Boyoung
authors.initials: B
authors.lastname: Joung
authors.affiliation: Yonsei University Health System, Seoul, Korea (J.P., T.H.K., J.S.L., J.K.P., J.S.U., B.J., M.H.L., H.N.P.).
authors.forename: Moon Hyoung
authors.initials: MH
authors.lastname: Lee
authors.affiliation: Yonsei University Health System, Seoul, Korea (J.P., T.H.K., J.S.L., J.K.P., J.S.U., B.J., M.H.L., H.N.P.).
authors.forename: Hui-Nam
authors.initials: HN
authors.lastname: Pak
mesh_terms: D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000401:mortality / Q000601:surgery*; D064752:Atrial Remodeling / Q000502:physiology*; D018780:Body Surface Potential Mapping / Q000379:methods*; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012008:Recurrence; D018570:Risk Assessment; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000889:Anti-Arrhythmia Agents
keywords: PR interval; atrial fibrillation; catheter ablation; recurrence; remodeling