title: Large tip electrodes for successful elimination of atrial flutter resistant to conventional catheter ablation.
abstract: The most widely accepted criterion for successful radiofrequency catheter (RFC) ablation of typical atrial flutter is the development of bi-directional isthmus block. In a subset of patients, conventional RFC ablation fails to achieve this endpoint because deeper and wider lesions are required. We investigated the efficacy of a long 8-mm tip catheter in these cases. One hundred and seventy-four consecutive patients (137 male; 61 +/- 9 years) with recurrent typical atrial flutter underwent conventional RFC ablation first with a standard 4 mm tip catheter. In resistant cases (n = 52), ablation was continued using a large tip 8-mm catheter when the 4-mm tip catheter failed. Resistant atrial flutter was identified when 21 RFC pulses failed to reach the selected endpoint of bi-directional isthmus block or in cases of transient bi- directional block (at least 3 episodes). In 122 of the 174 patients (70%) conventional atrial flutter ablation was successfully performed with 13 +/- 5 RFC applications. In the remaining 52 subjects (30%), the ablation procedure was completed using the large tip electrode catheter. In 30 of these 52 patients (58%), the catheter was changed because of persistent intra-atrial conduction after 21 RFC pulses and in 22 (42%) because of intermittent conduction block after 11 +/- 5 applications. Using the large tip electrode catheter, the selected endpoint was achieved in all patients of both groups with 3 +/- 2 RFC pulses (power output of 50-60 W, pulse duration of 60 sec). No post-procedure complications were observed. After 15 +/- 5 months of follow-up, 16 patients (9%) had recurrence of atrial flutter. Five of the patients had been in the resistant group. In patients with atrial flutter resistant to conventional ablation therapy, the long tip (8-mm) catheter appears to be a safe and effective alternative to use of the conventional 4-mm tip catheter.
authors.affiliation: Department of Cardiology, University Hospital Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany. ventura@uke.uni-hamburg.de
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Ventura
authors.forename: Stephan
authors.initials: S
authors.lastname: Willems
authors.forename: Christian
authors.initials: C
authors.lastname: Weiss
authors.forename: Joerg
authors.initials: J
authors.lastname: Flecke
authors.forename: Tim
authors.initials: T
authors.lastname: Risius
authors.forename: Thomas
authors.initials: T
authors.lastname: Rostock
authors.forename: Matthias
authors.initials: M
authors.lastname: Hoffmann
authors.forename: Thomas
authors.initials: T
authors.lastname: Meinertz
mesh_terms: D001282:Atrial Flutter / Q000601:surgery*; D017115:Catheter Ablation / Q000295:instrumentation*; D004566:Electrodes; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors