Russian registry of cryoballon ablation of atrial fibrillation: characteristics of the procedure and features of patient’s management

Aim . To study the characteristics of the atrial fibrillation (AF) cryoballoon ablation (CBA) procedure and features of patient’s management in real clinical practice in Russia. Methods . “Prospective Atrial Fibrillation Cryoablation Registry” is an observational prospective national multicenter study. It was conducted from 01.2017 to 12.2019 in centers of Russian Federation. The registry included patients over the age of 18 who were agreed to participate this study and had indications for CBA of AF. The study protocol did not provide for significant restrictions on inclusion criteria, procedure technique and postoperative follow-up. The data was collected prior to the CBA of AF, during hospitalization for CBA and on the 12-month follow-up. Results . Participating centers enroll 980 patients according to inclusion criteria. CBA of AF was performed in 976 (99.6%) (mean age 59.7±9.2 years, 545 (55.8%) men) primary procedure - 840 (86.1%), re-ablation - 136 (13.9%). Parox- ysmal AF occurred in 828 (84.8%) patients and persistent AF (mean time of persistence 4.4±3.7 months) - in 145 (15.1%) patients. The average procedure time was 108.1±33.3 minutes and mean fluoroscopy time was 24.9±13.6 min. Most of the procedures were performed under general anesthesia. Complications after AF CBA occurred in 53 (5.4%) patients. The most common complication was paresis of the phrenic nerve - 20 (37.7%) cases which were associated with lower temperatures of CBA application of the right pulmonary veins (τ=0.08; p<0.05). The features of antiarrhythmic and anticoagulant therapy were evaluated. A group of patients without adequate anticoagulant therapy in the postoperative period was identified. Due to COVID-19 restrictions only 374 (38.3%) patients completed 12-month follow-up. The recurrence of arrhythmia was occurred in 85 (22.7%) patients. Multivariate regression analysis revealed the following predictors of arrhythmia recurrence: the first procedure (OR 3.96; p=0.023), male sex (OR 1.77; p=0.014), duration of the procedure (min) (OR 1.01; p=0.007). Conclusion . CBA is an effective and relatively safe procedure for the treatment of paroxysmal and persistent AF. Data from real clinical practice show a low proportion of serious complications of AF CBA. Data on the dynamics of drug therapy, including anticoagulant and antiarrhythmic therapy, were obtained. The attention of specialists performing AF catheter ablation and patient monitoring is required, since errors in patient management have been identified.