Is it possible to perform a linear lesion with no local electrograms using a three-dimensional mapping system for the ablation of typical atrial flutter?

Abstract

Aims: A randomized prospective study to evaluate the efficacy, safety and long-term outcomes of the complete disappearance of local electrograms along the linear lesion using the EnSite NavX three-dimensional mapping system compared to the conventional fluoroscopy-based mapping for the ablation of typical atrial flutter (AFL).

Methods: 83 patients with spontaneous AFL episodes were randomized to the conventional procedure (group I, 41 patients) or to the EnSite NavX three-dimensional mapping system (group II, 42 patients). When bidirectional block was achieved, a renavigation of the ablation line was performed to verify the absence of local potentials along the line.

Results: In all patients, bidirectional isthmus block was achieved. Total mean fluoroscopy time was 19.8 +/- 4.1 min and 9.1 +/- 3.5 min (p < 0.001) and radiofrequency (RF) mean fluoroscopy time was 6.9 +/- 1.4 min and 0.6 +/- 0.3 min (p < 0.001), respectively, in group I and II. During long-term follow-up of 16 +/- 9 months, there were 4 (10%) AFL recurrences in group I and 0 in group II (p < 0.005).

Conclusion: NavX accurately renavigates the lesion line and verifies local potentials. The electro-anatomic activation map accurately identifies gaps in the RF lesion line and no recurrences were found compared with 10% recurrences after standard procedures for typical AFL.