title: Impact of Impaired Renal Function on the Incidence of Atrial Fibrillation following Radiofrequency Ablation of Cavotricuspid Isthmus-Dependent Atrial Flutter.
abstract: OBJECTIVE
  Atrial fibrillation (AF) occurs frequently after successful radiofrequency ablation (RFA) of cavotricuspid isthmus-dependent atrial flutter (CTI-AFL). Renal impairment has been implicated in the development of AF. The purpose of this study is to clarify the impact of impaired renal function on the incidence of AF after RFA of CTI-AFL.
  
  
  METHODS
  Between January 2001 and December 2013, 240 non-dialysis patients with no prior history of AF {mean age 55.9±15.2 years old; male, 192 (80.0%)} who had undergone successful CTI-AFL ablation were included in the present study. The baseline estimated glomerular filtration rate was calculated, and patients were divided into those with impaired renal function (<60 mL/min/1.73 m(2)) and those with preserved renal function (≥ 60 mL/min/1.73 m(2)). The incidence of AF was retrospectively analyzed.
  
  
  RESULTS
  69 (28.8%) patients experienced new onset AF during a median follow-up duration of 26 months (inter-quartile, 7-53). The incidence of AF was significantly higher in patients with impaired renal function than in those with preserved renal function {13/25 (52.0%) versus 56/215 (26.0%), log rank p=0.019}. Age, CHADS2 score, impaired renal function, and left atrial diameter were significantly associated with the incidence of AF in univariate Cox regression analysis. Multivariate analysis showed that age was the only significant predictor of AF incidence (hazard ratio, 1.024; 95% confidence interval, 1.004-1.044, p=0.020).
  
  
  CONCLUSIONS
  Patients with impaired renal function may require careful attention for the incidence of new onset AF following successful RFA of CTI-AFL.
authors.affiliation: Division of Cardiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul, Korea.
authors.forename: Chang Hee
authors.initials: CH
authors.lastname: Kwon
authors.affiliation: Division of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jun
authors.initials: J
authors.lastname: Kim
authors.affiliation: Division of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Min Su
authors.initials: MS
authors.lastname: Kim
authors.affiliation: Division of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jae-Hyung
authors.initials: JH
authors.lastname: Roh
authors.affiliation: Division of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jin Hee
authors.initials: JH
authors.lastname: Choi
authors.affiliation: Division of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Uk
authors.initials: U
authors.lastname: Jo
authors.affiliation: Division of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Woo Seok
authors.initials: WS
authors.lastname: Lee
authors.affiliation: Division of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Yoo Ri
authors.initials: YR
authors.lastname: Kim
authors.affiliation: Division of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Gi-Byoung
authors.initials: GB
authors.lastname: Nam
authors.affiliation: Division of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Kee-Joon
authors.initials: KJ
authors.lastname: Choi
authors.affiliation: Division of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: You-Ho
authors.initials: YH
authors.lastname: Kim
keywords: Atrial fibrillation; Atrial flutter; Catheter ablation; Renal insufficiency