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™.