Comparative Effectiveness and Safety of Cryoablation Versus Radiofrequency Ablation Treatments for Persistent Atrial Fibrillation.

The purpose of this study was to compare the effectiveness and safety of 2 strategies for catheter treatment of patients with persistent atrial fibrillation in the long-term period, using cardiac implantable loop recorders. The research is a prospective, randomized, controlled study designed to compare the results of modern catheter technologies in patients with persistent atrial fibrillation. The study included 127 patients with persistent atrial fibrillation in the last 6 months before inclusion in the study, for whom at least 2 antiarrhythmic drugs of class I to III were not effective. By random distribution, 50 patients were included in group 1; they underwent cryoballoon ablation, using a cryoballoon of the second generation. Group 2 also included 50 patients who underwent radiofrequency ablation, where a catheter was used to control the contact force. Cardiac implantable loop electrocardiogram recorders were implanted in all patients after surgery. The average duration of follow-up was 36 months. The primary end point of efficacy occurred in 15 patients in the group with cryoballoon ablation and 14 patients in the group with radiofrequency ablation. In conclusion, the primary effectiveness was relatively the same in the groups; yet, in the long-term period, the superiority of radiofrequency ablation using catheters with pressure control was noted, but the difference in results was statistically insignificant (p <0.672) and there was no significant difference between the 2 methods in terms of overall safety.

The efficacy and safety of cryoballoon catheter ablation in patients with paroxysmal atrial fibrillation.

BACKGROUND: Electrical isolation of pulmonary vein ostia is an established therapy for paroxysmal atrial fibrillation. AIMS: The purpose of this study is to evaluate the long-term efficacy and safety of cryoballoon catheter ablation in paroxysmal atrial fibrillation with normal anatomy of the left atrium. METHODS: Two hundred fifteen consecutive patients were included in the study (from November 2014 to November 2016). All the patients had symptoms of paroxysmal atrial fibrillation resistant to antiarrhythmic drugs and underwent pulmonary vein cryoisolation using second-generation cryoballoons. Standard "single-shot" cryoballoon exposures were used alternately for each of the four pulmonary veins. The endpoint of the ablation procedure was the electrical isolation of each pulmonary vein. RESULTS: Sixty-nine patients had stable atrial fibrillation recurrences and left atrial flutter with 30 of 69 patients having atrial fibrillation paroxysms during the first year after primary ablation. Repeated ablation was performed within 6-12 months after the first ablation. In 39 of 69 cases, arrhythmia recurrences were registered during the second and third year after the first ablation. These patients underwent repeated ablation within 12-36 months after the first ablation. In 98% of the patients, no disease progression with a transition to a persistent form of atrial fibrillation was observed. During the mean 5-year follow-up period, no disease progression with the transition to persistent forms of atrial fibrillation was observed. CONCLUSIONS: It was concluded that in patients with paroxysmal atrial fibrillation, with normal left atrium anatomy and no risk factors, it can be controlled with single pulmonary vein isolation without additional atrial substrate modification.