The value of the ablation index in patients undergoing ablation for atrial fibrillation

Abstract

Background: Data on the results of ablation for atrial fibrillation (AF) in Poland are scarce.

Aims: The aim of the study was to compare the efficacy of ablation index (AI)-guided pulmonary vein isolation (PVI) with that of conventional contact force–based PVI.

Methods: Consecutive patients undergoing PVI for the first time were included in the study. A nonrandomized retrospective comparison was made between patients ablated with contact force before AI was introduced (non -AI group) and patients ablated with the use of AI (AI group). The AI threshold for the anterior wall / roof of left veins was 500 and 380 elsewhere. The maximal interlesion distance was 6 mm. The follow -up included outpatient visits and 7-day Holter monitoring 6 and 12 months after ablation.

Results: A total of 275 patients were included in the analysis: 133 in the AI group and 142 in the non--AI group. The duration of AF ablation was slightly longer in the AI group, but the fluoroscopy time and the radiofrequency ablation time were shorter in the same group. During the 12-month follow -up period, 25.8% and 40.6% of patients from the AI and non -AI groups, respectively, experienced recurrences (P = 0.02). The log -rank test with an extended follow -up period of up to 18 months confirmed the difference between the AI and non -AI groups, both in the whole group and in the paroxysmal AF and nonparoxysmal AF subgroups (P = 0.001, P = 0.04, and P = 0.006, respectively).

Conclusion: The AI -based protocol provides a significant advantage over traditional contact force–based radiofrequency ablation in nonselected patients undergoing PVI.