RADIOFREQUENCY CATHETER ABLATION OF COMMON ATRIAL-FLUTTER - COMPARISON OF ELECTROPHYSIOLOGICALLY GUIDED FOCAL ABLATION TECHNIQUE AND LINEARABLATION TECHNIQUE

Objectives. The purpose of this study was to study electrophysiologic characteristics and compare the electrophysiologically guided focal ab lation technique and linear ablation technique in patients with common atrial flutter in a prospective randomized fashion, Background. Cathe ter ablation of the common atrial flutter circuit can be performed wit h different techniques. To date, these. two techniques have not been c ompared prospectively in a randomized study. Methods. Sixty patients w ith drug-refractory common atria! Butter were randomly assigned to und ergo radiofrequency catheter ablation performed with the electrophysio logically guided focal ablation (Group I) or linear ablation technique (Group II). In Group I, radiofrequency energy was delivered to the si te characterized by concealed entrainment with a short stimulus-P wave interval (<40 ms) and a postpacing interval equal to the atrial Butte r cycle length. In Group II, continuous migratory application of radio frequency energy was used to create the linear lesions in or around th e inferior vena cava-tricuspid ring isthmus. Serial 24-h ambulatory el ectrocardiographic (Holter) and follow-up electrophysiologic studies w ere performed to assess recurrence of tachycardia and possible atrial arrhythmogenic effects. Results. Successful elimination of the Butter circuit was achieved in 28 of 30 patients in Group I and 29 of 30 pati ents in Group II, More atrial premature beats and episodes of short ru n atrial tachyarrhythmias in the early period (within 2 weeks) after a blation were found in Group II. Recurrence rate (2 of 28 vs. 3 of 29) and incidence of new sustained atrial tachyarrhythmias (3 of 28 vs, 3 of 29) was similar in the two groups, Occurrence of recurrent atrial B utter and new sustained atrial tachyarrhythmias was related to associa ted cardiovascular disease and atrial enlargement in both groups. Howe ver, in Group II, the procedure time (104 +/- 17 vs. 181 +/- 29 min, p < 0.01) and radiation time (22 +/- 8 vs. 42 +/- 13 min, p < 0.01) wer e significantly shorter than those in Group I. Conclusions. Radiofrequ ency ablation of the common atrial Butter circuit was safe and effecti ve with either the electrophysiologically guided focal ablation or lin ear ablation technique. However, the linear ablation technique was tim e-saving.