title: Long-term efficacy of cryo catheter ablation for the treatment of atrial flutter: results from a repeat electrophysiologic study.
abstract: OBJECTIVE
  We investigated the long-term efficacy of cryo ablation for treatment of atrial flutter.
  
  
  BACKGROUND
  To our knowledge, no study has assessed the long-term efficacy of cryo ablation by assessing both symptom and conduction recurrence.
  
  
  METHODS
  A total of 45 consecutive patients with symptomatic atrial flutter were ablated with a 7-F, 6-mm-tip, quadripolar cryo catheter (Freezor Xtra, CryoCath Technologies Inc., Kirkland, Canada). Electrophysiologic studies (EPS) were performed with diagnostic catheters. Cryo ablation was at -75 degrees C for 4 min, beginning at the inferior rim of the coronary sinus os and creating a posterior line to the Eustachian ridge. Safety, bi-directional isthmus block at intervention, and recurrence at three, six, and nine months post procedure were assessed.
  
  
  RESULTS
  There were no adverse events reported. All patients were free of discomfort on cryo energy delivery. The acute success rate at intervention was 87%. Follow-up data from 39 acutely successful patients showed 27 (69%) without conduction recurrence on repeat EPS at three months, and none (0%) had symptom recurrence documented by Holter monitoring, electrocardiogram, and/or patient diary records at three, six, and nine months follow-up.
  
  
  CONCLUSIONS
  Our experience with a new 7-F, 6-mm-tip, quadripolar cryo catheter yielded a fairly high success rate at intervention, an excellent safety profile, and a good chronic success rate in terms of symptom recurrence. However, further monitoring is necessary to determine whether all asymptomatic patients continue to remain free of symptoms, given the small pool of patients demonstrated to have conduction recurrence.
authors.affiliation: Cardiology Department and Arrhythmia Center of Policlinico MultiMedica, Sesto S.Giovanni, Milan, Italy. montenero@hotmail.com <montenero@hotmail.com>
authors.forename: Annibale S
authors.initials: AS
authors.lastname: Montenero
authors.forename: Nicola
authors.initials: N
authors.lastname: Bruno
authors.forename: Andrea
authors.initials: A
authors.lastname: Antonelli
authors.forename: Daniele
authors.initials: D
authors.lastname: Mangiameli
authors.forename: Luca
authors.initials: L
authors.lastname: Barbieri
authors.forename: Peter
authors.initials: P
authors.lastname: Andrew
authors.forename: Olive
authors.initials: O
authors.lastname: Murphy
authors.forename: Stephen
authors.initials: S
authors.lastname: O'Connor
authors.forename: Francesco
authors.initials: F
authors.lastname: Zumbo
mesh_terms: D000368:Aged; D001282:Atrial Flutter / Q000503:physiopathology / Q000601:surgery*; D006328:Cardiac Catheterization; D003452:Cryosurgery / Q000379:methods; D004562:Electrocardiography; D004594:Electrophysiology; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D013997:Time Factors