Abstract 11800: Association Between Balloon Temperature Profile and Outcome of Pulmonary Vein Isolation With 2nd-generation Cryoballoon

Introduction:Various factors have been reported as predictors of outcomes after pulmonary vein isolation (PVI) with the 2nd-generation cryoballoon (CB), however, few reports exist regarding the details of ice formation on CB surface during PVI. In the current study, we aimed to explore and analyze parameters that reflect sufficient ice formation and CB-PVI outcome.Methods:The study subjects were consecutive 106 patients (64 ? 10 years, 35 female) who underwent successful PVI by CB for atrial fibrillation (AF), in whom each PV was attempted to be isolated with a single shot of CB application. We evaluated the following parameters during CB application: PV occlusion score; nadir balloon temperature; total freezing time; thawing time, defined as the time between the end of CB application and deflation; and temperature drop, defined as a temperature drop of more than 3?C just after CB catheter bending. We divided the study patients into three groups based on a temperature drop during CB: Group 1 with temperature drop in all PVs; Group 2 with temperature drop in 1-3 PVs; and Group 3 without temperature drop in any PV.Results:With a mean follow up period of 376 ? 217 days, 19 patients (18%) experienced AF recurrence. Kaplan-Meier survival analysis revealed that no patients in Group 1 experienced AF recurrence, 14 out of 86 patients (16%) experienced AF recurrence in Group 2, and five out of 10 (50%) patients experienced AF recurrence in Group 3 (Log-Rank P = 0.003). Multivariable Cox regression analysis revealed that the number of PVs with a temperature drop was a strong predictor of AF recurrence after PVI with CB (HR: 6.009, P <0.001).Conclusions:The temperature drop immediately after CB catheter bending might reflect the state of ice formation and can be used to predict clinical outcome after PVI using 2nd-generation CB.