This document provides an overview of current problems and trends in the catheter ablation of atrial fibrillation, summarizes the opinions of specialists, obtained during a web-based electronic survey, on aspects and parameters of radiofrequency ablation. The approaches on improving the efficacy and safety of radiofrequency catheter ablation of atrial fibrillation are provided.

Aim. To analyze the success rate and other intraprocedural parameters of implantation His bundle pacing lead using different approaches.Methods. Since 2018 to 2022 we have tried His bundle lead implantation in 32 pts. During implantation 4 different approaches were used: on-stylet in 6 pts (19%), on-stylet over the delivery tool in 9 pts (28%), over the C304 SelectSite (Medtronic, USA) delivery tool in 10 pts (31%), over the modified C304 SelectSite delivery tool in 12 pts (37%).Results. Four studied implantation approaches did not differ by means of procedure duration as well as lead parameters. The success rate of implantation using modified C304 SelectSite delivery tool was higher than using other 3 techniques (91,7% vs 44%, p-0,006).Conclusion. His bundle lead implantation success depends significantly on chosen implantation technique.

Aim. Cryoballoon ablation (CBA) is one of the methods for catheter pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (AF). Left atrial additional lesion (LAAL) to PVI were proposed to eliminate extrapulmonary AF triggers. Nonetheless whether the additional lesions improve CBA effectiveness is not clear.Methods. Primary CBA procedures performed for paroxysmal AF during 2017-2021 were analyzed. The study group (Algorithm group, n=82) was recruited prospectively in 2019-2021. As the first step CBA PVI were performed in all pts. In those who were on sinus rhythm (SR) after the PVI, AF induction attempts with burst atrial pacing were performed. Pts with induced AF and those who stayed on AF after PVI underwent LAAL at the left ganglionated plexus area. In case of stable SR (non-inducible AF) the procedure finished. If AF was inducible or did not terminate during CBA, the second LAAL set were performed - LA posterior wall lesions. If AF was still inducible or did not terminate, the SR was restored by electrical cardioversion. The control group (Control group, n=94) was formed retrospectively from patients with routinely performed only CBA PVI with achievement of isolation criteria in 2017-2019. If AF continued, sinus rhythm was restored by cardioversion. There were no attempts of induction AF during the procedure.Results. The Algorithm and Control groups were comparable in terms of clinical, demographic and electrophysiological characteristics. At 12 months postoperatively, the effectiveness was higher in the Algorithm group than in the Control group (78.0% vs. 62.8%, p = 0.044). No adverse effects were found.Conclusion. Thus, the stepwise approach with LAAL increases the effectiveness of CBA in the long-term period and does not affect the risk of complications.