Left atrial posterior wall isolation in persistent atrial fibrillation does not influence the efficacy of catheter ablation: a pilot study

Abstract

Aim. To study the role of left atrial posterior wall (LAPW) isolation in increasing the clinical efficacy of radiofrequency ablation (RFA) in patients with persistent atrial fibrillation (PeAF) during electrophysiological studies.Methods. A single-center randomized prospective study. From February 2020 to February 2021, 35 procedures were performed on patients with PeAF. Patients were randomized into two groups - pulmonary vein isolation (PVI) plus LAPW isolation according to the “box lesion” scheme (the first group) and the PVI-only group (the second group). If it was impossible to achieve LAPW isolation, “debulking” was performed. After 3 months, regardless of the clinical status, EPS and RFA of the reconnection zones were performed.Results. The full study protocol study was completed by 30 patients - 14 in the first group and 16 in the second group. The characteristics of the patients in the groups did not differ statistically. The duration of the primary and redo procedures, as well as the RFA time during the primary procedure in the first group is significantly longer than in the second group. Pulmonary veins were isolated in all patients participating in the study. In the first group, LAPW isolation was achieved only in 21.4% of cases (3 patients), in the remaining 78.6% of cases (11 patients) “debulking” was performed. PVI in the first group was maintained in 78.6% of cases (11 patients), and in the second group in 56.2% (9 patients), the difference was not statistically significant (p=0.209). In the first group, LAPW isolation was maintained in 28.6% of patients (4 patients). All patients with reconnection underwent RFA with the restoration of the conduction block. In the midterm (440±82.1 days) of follow-up, the sinus rhythm was preserved in the first group in 11 patients (78.5%), and in the second group in 13 (81.2%) patients. There was no statistically significant difference between the groups (OR 0.846 95% CI 0.141-5.070, p=0.641).Conclusions. In our study, LAPW isolation in addition to PVI in patients with PeAF did not improve the efficacy of treatment with a significantly longer duration of procedure and RFA time.