Individualized radiofrequency ablation of non-paroxysmal atrial fibrillation based on mapping of spatiotemporal dispersion zones: clinical results

Abstract

Aim. to evaluate the results of pulmonary vein isolation (PVI) and spatio-temporal dispersion (STD) radiofrequency ablation (RFA) and the recurrence rate of atrial fibrillation (AF) in patients with non-paroxysmal AF after intraoperative intravenous administration of novocainamide. Methods. The study included 67 patients with persistent and long-standing persistent AF who underwent the primary RFA PVI and STD procedure. Stages of the operation: coronary sinus catheterization, interatrial septum puncture twice, PVI, administration of novocainamide in the right atrium, mapping and RFA of STD zones in the left atrium, ifnecessary, in the right atrium and in the coronary sinus. The final goal of RFA was conversion to sinus rhythm (SR) or transformation into atrial flutter (AFl)/regular atrial tachycardia (AT) with subsequent mapping and RFA. If AF/AFl/AT persisted, an electrical cardioversion (ECV) was performed. Then, PVI and linear blocks were evaluated/restored. An electrocardiogram and Holter monitoring were recorded at 3 and 6 months later to analyze the effectiveness. Results. PVI was achieved in each case. Acute conversion of AF to SR occurred in 7 patients (10.4%), in sustained AFl/AT in 26 (38.8%). In 18 of 26 patients (69.2%), AFl/AT were ablated with SR restoration. 42 patients (62.7%) required ECV. After 3 months, there was no recurrence of AF in 40 patients (88.9%), AF/AFl/AT in 31 (68.9%), 6 months later in 32 (80%) and 24 (60%) respectively. There were no differences in freedom from AF/AFl/AT 6 months later between the AF and ECV group at the end of the procedure and the SR/AFl/AT group (log-rank=0.333), while the latter had significantly fewer AF recurrences (log-rank=0.004). In patients who converted to SR/AFl/AT during RFA, the probability of AF recurrence during the 6-month follow-up period was 10 times lower than in patients with persistent AF and ECV (OR 10.4 (95% CI 1.351-81.120), p=0.025. Conclusion. In 49.3% of cases, AF was stopped during RFA PVI and STD. The probability of AF recurrence in this case was 10 times lower than in the case of persistent AF and ECV at the end of the operation. There were no differences in the absence of AF/AFl/AT recurrence between patients with intraoperative conversion to SR/AFl/AT and persistent AF.