Short- and long-term results of catheter ablation for atrial fibrillation under the guidance of the “Ablation Index” module

Aim. Comparative evaluation of short-term and long-term outcomes of radiofrequency pulmonary vein isolation using the “Ablation Index” module versus without in patients with paroxysmal and persistent forms of atrial fibrillation.

Methods. The study included 286 patients with paroxysmal and persistent forms of atrial fibrillation, divided into 2 groups: the study group (110 patients) underwent radiofrequency pulmonary vein isolation using the “Ablation Index” module, while the control group (176 patients) underwent isolation without the use of the “Ablation Index” module.

Results. The average follow-up period was 38.1±9.6 months. There was no significant difference in freedom from atrial tachyarrhythmias in the long-term follow-up between the study and control groups (58.1% vs. 62.3%, p=0.667), or in the number of perioperative complications (3.6% vs. 8.5%, p=0.106). A significant reduction in the duration of the procedure was observed when using the “Ablation Index” module (92.7±20.9 min vs. 126.4±29.2 min, p<0.001), as well as in the recurrence rate of atrial fibrillation in the blanking period (1.8% vs. 8.5%, p=0.020).

Conclusion. Interventional treatment of atrial fibrillation under the control of the “Ablation Index” module shows significantly lower recurrence rates of atrial tachyarrhythmias in the blanking period and comparable safety and long-term efficacy results compared to interventional treatment using catheters with contact force sensor over a period of more than three years.

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