Catheter Ablation of Atrial Flutter

Within the past years, refinements in electrophysiologic mapping techniques have provided a clear understanding of typical and atypical atrial flutter circuits. 1 2 3 Catheter mapping studies have indicated that a common myocardial “isthmus” between the inferior tricuspid annulus (TA) and the inferior caval vein is an integral part of the circuit in typical flutter. Linear lesions induced with radiofrequency (RF) catheter ablation have cured the arrhythmia by producing an electrically insulated barrier within this isthmus 4 ; thereby, isthmus ablation is the technique that has introduced the strategy of linear ablation instead of focal ablation as used for ablation of accessory pathways. In the current electrophysiologic laboratories, ablation of atrial flutter is the most frequent indication for ablation. This is supported by a recent population-based investigation of atrial flutter, suggesting that this arrhythmia is much more common than previously supposed with an estimated 200,000 new cases annually in the United States. 5 A prospective randomized comparison of antiarrhythmic therapy versus first-line RF ablation in patients with atrial flutter indicated that in selected patients, RF ablation could be considered a first-line therapy because of better success rates, a positive impact on quality of life, a lower occurrence of atrial fibrillation, and a lower need for rehospitalization at follow-up. 6 In our center, the recurrence of symptomatic or hemodynamically significant atrial flutter leads to an indication for ablation.