Evaluation and comparison of impedance and amplitude changes in lesion index-guided pulmonary vein isolation.

Background

The lesion index (LSI) has been used to estimate lesion formation after radiofrequency catheter ablation. However, the impedance drop and decrease in bipolar amplitude of intracardiac electrograms, which are parameters that are traditionally used to predict effective ablation lesions, are not used to calculate LSI. Therefore, we aimed to investigate the association between LSI and traditional parameters.

Methods

We retrospectively investigated 1355 ablation points from 31 patients who underwent LSI-guided pulmonary vein isolation (PVI) using TactiCath. All points were classified into 3 groups based on the impedance drop: (i) <10 Ω (

Results

The target LSI was achieved at 1177 points (86.9%). The median total impedance drop and amplitude just after ablation were 16.0 [13.0-20.0] Ω and 0.21 [0.14-0.30] mV, respectively. There were significant differences among the 3 groups in the impedance and amplitude before ablation, power, target LSI, final LSI, contact force, and interlesion distance. An impedance drop of >10 Ω or an amplitude reduction of >50% was achieved at 95% and 82% of the study points, respectively. There were no major complications at any of the ablation points.

Conclusion

LSI-guided PVI seemed to be useful for making sufficient ablation lesions, as assessed by the conventional parameters of impedance and amplitude change.

Informations de copyright

© 2023 The Authors. Journal of Arrhythmia published by John Wiley & Sons Australia, Ltd on behalf of Japanese Heart Rhythm Society.

Déclaration de conflit d'intérêts

Authors declare no conflict of interests for this article.