Anatomical and procedural predictors of pulmonary vein stenosis in the setting of second-generation cryoballoon ablation.

AIMS: Pulmonary vein stenosis (PVS) is a well recognized complication as a consequence of pulmonary vein isolation. In the current study, we sought to analyze potential anatomical and intraprocedural predictors of PVS during second-generation cryoballoon ablation, particularly focusing on the impact of freeze duration and number of cryoapplications.

METHODS: Fifty-four patients who underwent cryoballoon ablation for atrial fibrillation were included retrospectively in this study. All patients underwent cardiac-enhanced multidetector computed tomography both before and after the ablation. The exclusion criteria were any contraindications for the procedure, including the presence of an intracavitary thrombus, uncontrolled heart failure and contraindications to general anesthesia.

RESULTS: Mild (25-50%) PVS was only detected in one vein (0.4%) and neither moderate (50-75%) nor severe (>75%) PVS were found. Twenty-five pulmonary veins (12%) exhibited slight narrowing of the diameter (less than 25%). In the univariate analysis, a longer duration of cryoapplication and a larger pulmonary vein ostium preprocedure diameter and area were independently associated with pulmonary vein narrowing [odds ratio (OR): 1.004; confidence interval (CI): 1.001-1.008, P = 0.016; OR: 1.250, CI: 1.090-1.434, P = 0.001 and OR: 1.006; CI: 1.002-1.011, P = 0.006] respectively.

CONCLUSION: Longer duration of cryoablation, an increased number of applications per vein and larger pulmonary vein ostia are associated with a higher risk of pulmonary vein diameter and area reduction. These findings might suggest to lower the dosing to a single and shorter application if isolation is attained, to reduce the possibility of future pulmonary vein narrowing.