title: Electrophysiologic characteristics and catheter ablation of focal atrial tachycardia with more than one focus.
abstract: BACKGROUND
  Information about the electrophysiologic characteristics and long-term outcome of catheter ablation in patients with multiple focal atrial tachycardia (AT) is limited.
  
  
  OBJECTIVE
  The purpose of this study was to investigate the electrophysiologic characteristics and long-term outcome of catheter ablation in patients with multiple focal AT.
  
  
  METHODS
  Two hundred fifty-one patients who were referred for radiofrequency catheter ablation of focal AT were included for analysis.
  
  
  RESULTS
  Forty-four patients who had focal AT with more than one focus were identified. Comparing focal AT with a single focus to that with more than one focus, the existence of a left atrial focus, cardiovascular comorbidity, nonparoxysmal tachycardia, shortest tachycardia cycle length, success rate of the ablation, and procedure time all differed. Multivariate logistic analysis revealed that a left atrial focus, cardiovascular comorbidity, and shortest tachycardia cycle length were independent predictors of focal AT with more than one focus. Noncontact mapping of the right atrium revealed larger low-voltage zone and longer total activation time for focal AT with more than one focus. Patients who had focal AT with more than one focus and a failed ablation had a greater number of focal ATs and mechanisms of nonparoxysmal tachycardia. Multivariate logistic analysis revealed that only the number of focal ATs predicted a failed ablation.
  
  
  CONCLUSIONS
  Focal ATs with more than one focus have different electrophysiologic characteristics. This study provides new insight into the development and atrial remodeling of focal AT with multiple foci.
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Hu
authors.forename: Satoshi
authors.initials: S
authors.lastname: Higa
authors.forename: Jin-Long
authors.initials: JL
authors.lastname: Huang
authors.forename: Ching-Tai
authors.initials: CT
authors.lastname: Tai
authors.forename: Yenn-Jiang
authors.initials: YJ
authors.lastname: Lin
authors.forename: Shih-Lin
authors.initials: SL
authors.lastname: Chang
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Lo
authors.forename: Ta-Chuan
authors.initials: TC
authors.lastname: Tuan
authors.forename: Chien-Jong
authors.initials: CJ
authors.lastname: Chang
authors.forename: Wen-Chin
authors.initials: WC
authors.lastname: Tsai
authors.forename: Pi-Chang
authors.initials: PC
authors.lastname: Lee
authors.forename: Sugako
authors.initials: S
authors.lastname: Ishigaki
authors.forename: Asuka
authors.initials: A
authors.lastname: Oyakawa
authors.forename: Shih-Ann
authors.initials: SA
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017115:Catheter Ablation / Q000379:methods*; D016009:Chi-Square Distribution; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D018709:Statistics, Nonparametric; D013617:Tachycardia, Supraventricular / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome