Introduction
Atrial fibrillation (AF) is the most common sustained arrhythmia worldwide. According to the Global Burden of Disease study, it affects 33.5 million individuals and its incidence is increasing every decade1. Consequences are cerebrovascular events, heart failure, impaired quality of life, and increased mortality2,3. Multiple trials have shown that catheter ablation is superior to antiarrhythmic drugs in reducing AF recurrence, alleviating symptoms, and mortality, in heart failure context4–6.
Cryoablation is a valid option for the classical point-by-point radiofrequency (RF) pulmonary vein isolation (PVI), with well-designed, randomized studies showing its non-inferiority when compared to RF catheter ablation7,8. The Medtronic’s cryoballoon (CB) overtime passed through many modifications seeking to improve quality. Compared to the first-generation CB Arctic Front™ (CB-1) (Medtronic, Minneapolis, USA), Arctic Front Advance™ (CB‐2) (Medtronic, Minneapolis, USA) presented enhanced distal hemisphere freezing, leading to a higher rate of acute PVI, shorter procedural times, and comparable safety9. The Arctic Front Advance ST™ (CB-3) (Medtronic, Minneapolis, USA) had a shorter distal nose‐tip on the balloon, what facilitated the real-timed assessment of pulmonary vein potentials10. Currently, most AF cryoablations are performed using the Arctic Front Advance PRO™ system (Medtronic, Minneapolis, USA), the 4th generation device, characterized by better catheter maneuverability and ergonomics, achieving shorter procedural times11.
Recently, the POLARx™ (Boston Scientific, Marlborough, MA, USA) cryoballoon received CE-Mark and started to be used in Europe. The system has the same cryoablation workflow of the state‐of‐the‐art cryoablation technology, with some improvements to, theoretically, improve outcomes. So far, its clinical evidence is restricted to a case report12. Thus, we decided to perform this study comparing the POLARx™ CB to the already established Arctic Front Advance PRO™.