title: History of hyperthyroidism and long-term outcome of catheter ablation of drug-refractory atrial fibrillation.
abstract: BACKGROUND
  Hyperthyroidism is a known reversible cause of atrial fibrillation (AF). However, some patients remain in AF despite restoration of euthyroid status.
  
  
  OBJECTIVE
  The purpose of this study was to compare the electrophysiologic characteristics and long-term ablation outcome in AF patients with and without history of hyperthyroidism.
  
  
  METHODS
  The study enrolled 717 consecutive patients with AF who underwent first AF ablation, which involved pulmonary vein (PV) isolation in paroxysmal AF and additional substrate modification in nonparoxysmal AF patients. Eighty-four patients (12%) with hyperthyroidism history were compared to those without. Euthyroid status was achieved for ≥3 months before ablation in hyperthyroid patients.
  
  
  RESULTS
  Patients with hyperthyroid history were associated with older age, more female gender, lower mean right atrial voltage, higher number of PV ectopic foci (1.3 ± 0.4 vs 1.0 ± 0.2, P < .01), and higher prevalence of non-PV foci (42% vs 23%, P < .01). Ectopic foci from ligament of Marshall were demonstrated more often in hyperthyroid patients (7.1% vs 1.6%, P < .01) in whom alcohol ablations were required. After propensity score matching for potential covariates, history of hyperthyroidism was an independent predictor of AF recurrence after single procedure (hazard ratio 2.07, 95% confidence interval 1.27-3.38). AF recurrence rates after multiple procedures were not different between patients with and those without hyperthyroid history.
  
  
  CONCLUSIONS
  Patients with hyperthyroid history had a significantly higher number of PV ectopies and higher prevalence of non-PV ectopic foci compared to euthyroid patients, which resulted in a higher AF recurrence rate after a single procedure.
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Wanwarang
authors.initials: W
authors.lastname: Wongcharoen
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan. Electronic address: linyennjiang@gmail.com.
authors.forename: Yenn-Jiang
authors.initials: YJ
authors.lastname: Lin
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Shih-Lin
authors.initials: SL
authors.lastname: Chang
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Lo
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Hu
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Fa-Po
authors.initials: FP
authors.lastname: Chung
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Division of Cardiology, Medicine Department, Jurong Health, Singapore.
authors.forename: Eric
authors.initials: E
authors.lastname: Chong
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Tze-Fan
authors.initials: TF
authors.lastname: Chao
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Ta-Chuan
authors.initials: TC
authors.lastname: Tuan
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Yao-Ting
authors.initials: YT
authors.lastname: Chang
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chin-Yu
authors.initials: CY
authors.lastname: Lin
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Jo-Nan
authors.initials: JN
authors.lastname: Liao
authors.affiliation: Division of Endocrinology and Metabolism, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Yi-Chun
authors.initials: YC
authors.lastname: Lin
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Yun-Yu
authors.initials: YY
authors.lastname: Chen
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Faculty of Medicine, Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Shih-Ann
authors.initials: SA
authors.lastname: Chen
mesh_terms: D001281:Atrial Fibrillation / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria / Q000503:physiopathology*; D006801:Humans; D006980:Hyperthyroidism / Q000097:blood / Q000150:complications* / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery*; D012008:Recurrence; D012189:Retrospective Studies; D013963:Thyroid Hormones / Q000097:blood; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D013963:Thyroid Hormones
keywords: Ablation; Atrial fibrillation; Hyperthyroidism; Ligament of Marshall; Pulmonary vein isolation