Atrial Fibrillation in the Blanking Period Is Not Associated with Late Recurrence after Cryoballoon Pulmonary Vein Isolation

Background: The clinical significance of atrial fibrillation (AF) during first 3 months (blanking period) after cryoballoon pulmonary vein isolation (PVI) is controversal. We assessed the impact of these early recurrences on the 12 month freedom of AF in patients undergoing cryoballoon PVI.

Patients and methods: Consecutive 141 patients with symptomatic AF undergoing cryoballoon PVI in our institution were enrolled (age 37-82, mean 64.5±8.9 years, 39% female, 65% persistent AF, mean CHA₂DS₂VASc score 2.3±1.5). Full PVI was achieved in 89%.

Results: After 12 months’ follow up, excluding 3 months blanking period, 13.5% of patients experienced at least one clinical AF event, defined as the cardioversion or hospitalization or ED visit for AF or presence of AF at the follow up visit. The AF recurrence was 2.0% in paroxysmal versus 19.6% in persistent AF.

Of 141 patients, 10 (7.0%) had AF recurrence during blanking period. Kaplan Meier analysis demonstrated freedom of clinical AF events after 1 year in 100% vs 85.5%, p=0.214 in patients with early AF recurrence versus those without early recurrence. When devided into paroxysmal and persistent AF groups, freedom of clinical AF events after 1 year was 100% vs 97.8%, p=0.808 and 100% vs 78.8%, p=201 in patients with paroxysmal and persistent AF, respectively.

Conclusion: Cryoballoon PVI is highly effective in maintaining sinus rhythm in after one year in patients with paroxysmal AF and has a significant efficacy in persistent AF patients. AF recurrence during blanking period was not associated with late AF recurrence after 1 year follow up. No patient with early recurrence had late recurrence of atrial fibrillation in both paroxysmal and persistent AF groups.