Randomized comparison of multipolar, duty-cycled, bipolar-unipolar radiofrequency versus conventional catheter ablation for treatment of common atrial flutter

Abstract

Introduction: Radiofrequency (RF) catheter ablation has been established as an effective and curative treatment for atrial flutter (AFL). Approved methods include a drag-and-drop method, as well as a point-by-point ablation technique. The aim of this study was to compare the acute efficacy and procedural efficiency of a multipolar linear ablation catheter with simultaneous energy delivery to multiple catheter electrodes against conventional RF for treatment of AFL.

Methods: Patients presenting to our department with symptomatic, typical AFL were enrolled consecutively and randomized to conventional RF ablation with an 8-mm tip catheter (ConvRF) or a duty-cycled, bipolar-unipolar RF generator delivering power to a hexapolar tip-versatile ablation catheter (T-VAC) group. For both groups, the procedural endpoint was bidirectional cavotricuspid isthmus block.

Results: Sixty patients were enrolled, 30 patients each assigned to ConvRF and T-VAC groups. Total procedure time (40.2 ± 15.8 min vs 60.5 ± 12.7 min), energy delivery time (8.5 ± 3.7 min vs 14.7 ± 5.2 min), radiation dose (14.5 ± 3.5 cGy/cm² vs 31.7 ± 12.1 cGy/cm²), and the minimum number of RF applications needed to achieve block (4.2 ± 2.4 vs 8.9 ± 7.2) were significantly lower in the T-VAC group. In 7 patients treated with the T-VAC catheter, bidirectional block was achieved with less than 3 RF applications, versus no patients with conventional RF energy delivery.

Conclusion: The treatment of typical AFL using a hexapolar catheter with a multipolar, duty-cycled, bipolar-unipolar RF generator offers comparable effectiveness relative to conventional RF while providing improved procedural efficiency.