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

D-PO02-162 - Non-occlusive Balloon Cryothermal Applications To Achieve Antral Isolation During Pulmonary Vein Isolation (ID 234)


Background: AF ablation requires wide area circumferential antral electrical isolation of the pulmonary veins (PV). Cryoballoon ablation delivers cryoenergy circumferentially after occlusion of the PV by the cryoballoon. The level of isolation is determined by adequate balloon-tissue contact and PV anatomy.
Objective: We aimed to examine the need for non-occlusive segmental cryoballoon ablation in achieving antral isolation and describe methods of accurate visualization of the cryoballoon using ICE.
Methods: Forty patients undergoing cryoablation with a second generation 28mm cryoballoon and NAVX/ESI or CARTO electroanatomical mapping (EAM) were include. Occlusive cryo-applications, confirmed with contrast or pressure guidance, were delivered in all cases except for common left PV. Delivery of non-occlusive lesions was based on level of isolation after occlusive lesions and guided by EAM and/or ICE. Post-ablation EAM were used to calculate non-ablated antral PV and posterior wall areas.
Results: Non-occlusive lesions were delivered in 26 of 40 patients (65%) or 46 out of 148 veins (31%). Left PVs >19.4±2.9mm, right superior PV >20.2±4.7mm, funnel shaped PVs, and right PVs not converging to a carina were more likely to require non-occlusive lesions. Non-occlusive lesions were successful in extending the level of isolation in all cases. Projection of balloon contour on EAM using CARTO Sound successfully predicted level of isolation by voltage mapping.
Conclusion: Non-occlusive cryoballoon lesions are commonly required to achieve antral isolation. Use of ICE can be helpful in determining the accurate location of the balloon and in predicting the level of isolation by voltage map.