Is 8-mm more effective than 4-mm tip electrode catheter for ablation of typical atrial flutter?

Abstract

BACKGROUND:

The prospective, randomized study comparing 4- with 8-mm tip electrodes for radiofrequency linear ablation of typical atrial flutter is not available.

METHODS AND RESULTS:

A total of 104 consecutive patients with typical atrial flutter were randomly assigned to undergo radiofrequency linear ablation using a 4- (Group I, n=54) or 8-mm tip electrode (Group II, n=50) catheter (temperature-control model, preset 70 degrees C). If complete bidirectional isthmus block could not be achieved after 5 pulses, the ablation catheter was changed to the other type; the maximal radiofrequency pulse number was limited to <10 pulses. Complete or incomplete isthmus conduction block was assessed by activation sequence in a multielectrode Halo catheter during low lateral right atrial and proximal coronary sinus pacing. Before shifting to the other catheter type, the 8-mm electrode catheter achieved higher complete isthmus block rate (92% versus 67%, P<0.05) with fewer pulses (2+/-1 versus 3+/-1, P<0.05), shorter procedure time (24+/-15 versus 31+/-12 minutes, P<0.05), and shorter fluoroscopic time (14+/-10 versus 23+/-15 minutes, P<0.05). After 5 failed ablation pulses, 12 (67%) of 18 patients in group I attained complete isthmus block by using an 8-mm tip catheter, but none of 4 patients in group II achieved complete block by changing to a 4-mm tip catheter.

CONCLUSIONS:

The 8-mm tip electrodes are more effective than the standard 4-mm length electrodes in linear ablation for typical atrial flutter. This clinical benefit may be of particular value for some patients with broad and/or thick isthmus.

• Authors: C F Tsai, C T Tai, W C Yu, Y J Chen, M H Hsieh, C E Chiang, Y A Ding, M S Chang, S A Chen
• Journal: Circulation (Circulation) Vol. 100 Issue 7 Pg. 768-71 (Aug 17 1999) ISSN: 1524-4539 [Electronic] United States
• PMID: 10449701 (Publication Type: Clinical Trial, Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)

Topics

• Aged
• Atrial Flutter (surgery)
• Catheter Ablation (instrumentation)
• Electrodes
• Equipment Design
• Female
• Follow-Up Studies
• Humans
• Male
• Middle Aged
• Recurrence
• Treatment Outcome