Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Ablation Techniques D-PO02 - Poster Session II (ID 47) Poster

D-PO02-188 - Association Of Cryoballoon Freeze Duration With Atrial Fibrillation Recurrence After Pulmonary Vein Isolation (ID 1051)


Background: Data on the optimal freeze duration during Cryoballoon pulmonary vein isolation (CB-PVI) have been conflicting. Several studies suggested that 180 sec applications are as effective as 240 sec, while more recent data from the ICE Re-Map study demonstrated improved PVI durability with 240 sec.
Objective: To compare the long-term outcomes of 2 CB-PVI strategies: freeze duration of 240 sec x2 (CB-240s) vs. 180 sec x2 (CB-180s) per PV.
Methods: We included consecutive patients from a prospective registry undergoing first-time CB-PVI at our institution from April 2013 to April 2017. Patients were divided into 2 groups based on operator preference freeze duration strategy used during CB-PVI: CB-240s and CB-180s. The primary outcome was AF recurrence at 2 years following a single ablation procedure. Multivariable Cox Proportional Hazards model was used to assess the association of CB-PVI strategy with the time-to-AF recurrence.
Results: The study included 457 patients: 142 in the CB-240s group and 315 in the CB-180s group. The mean CHA2DS2-VASc score was similar between the 2 groups (1.77±1.4 vs 1.72±1.4 for the CB-240s and CB-180s groups respectively, P=0.8). There were more patients with persistent or long-standing persistent AF in the CB-180s group (N=78, 25.0%) compared to the CB-240s group (N=28, 19.8%, P=0.05). The total freeze duration per PV was 453±66 sec in the CB-240s group vs. 368±58 sec in the CB-180s group (P<0.001). At 2 years follow-up, AF recurrence occurred in 156 patients, 74 in the CB-240s group (52.1%) and 82 (26.0%) in the CB-180s group (P<0.001). With multivariable Cox Proportional Hazards analysis adjusting for CHA2DS2-VASc score, AF pattern, AF duration, left atrial size, left ventricular ejection fraction, presenting rhythm on the day of ablation, and other factors associated with AF recurrence on univariate analyses, there was no significant difference between the two freeze duration strategies as regards the time-to-AF recurrence at 2-years (HR 0.97 for CB-180s vs. CB-240s, 95% CI 0.39 - 2.46, P=0.9).
Conclusion: In a large cohort of patients undergoing first-time CB-PVI, a cryo dose of two-180 sec applications per pulmonary vein was associated with similar risk of AF recurrence at 2-years compared to two-240 sec applications.