Background: Atrial flutter is a common arrhythmia which frequently recurs after cardioversion and is relatively difficult to control with antiarrhythmic agents.
Aims: To evaluate the success rate, recurrence rate and safety of radiofrequency, (RF) ablation for atrial flutter in a consecutive series of patients with drug refractory chronic or paroxysmal forms of the arrhythmia.
Methods: Electrophysiologic evaluation of atrial flutter included activation mapping with a 20 electrode halo catheter placed around the tricuspid annulus and entrainment mapping from within the low right atrial isthmus. After confirmation of the arrhythmia mechanism with these techniques, an anatomic approach was used to create a linear lesion between the inferior tricuspid annulus and the eustachian ridge at the anterior margin of the inferior vena cava. In order to demonstrate successful ablation, mapping techniques were employed to show that bi-directional conduction block was present in the low right atrial isthmus.
Results: Successful ablation was achieved in 26/27 patients (96%). In one patient with a grossly enlarged right atrium, isthmus block could not be achieved. Of the 26 patients with successful ablation, there has been one recurrence of typical flutter (4%) during a mean follow-up period of 5.5 +/- 2.7 months. This patient underwent a successful repeat ablation procedure. Of eight patients with documented clinical atrial fibrillation (in addition to atrial flutter) prior to the procedure, five continued to have atrial fibrillation following the ablation. There were no procedural complications and all patients had normal AV conduction at the completion of the ablation.
Conclusions: RF ablation is a highly effective and safe procedure for cure of atrial flutter. In patients with chronic or recurrent forms of atrial flutter RF ablation should be considered as a first line therapeutic option.