Validation of electrical ostial pulmonary vein isolation verified with a spiral inner lumen mapping catheter during second-generation cryoballoon ablation.

BACKGROUND: Achieve catheters are cryoballoon guidewires that enable pulmonary vein (PV) potential mapping. The single catheter approach in conjunction with the Achieve catheter is currently standard practice in second-generation cryoballoon ablation, yet circumferential mapping catheters are the gold standard for evaluating PV isolation (PVI). The study sought to validate the ostial PVI verified by an Achieve catheter alone.

METHODS: One hundred fifty-one paroxysmal atrial fibrillation patients undergoing PVI using exclusively 28-mm second-generation cryoballoons were enrolled. PV recordings were analyzed during (real-time recordings) and after cryoballoon applications with 20-mm Achieve mapping catheters, and subsequently validated by 20-mm conventional circumferential mapping catheters.

RESULTS: Out of 596 PVs, 576 (96.6%) were isolated using cryoballoons, and 20 required touch-up ablation. PVI was verified during cryoballoon applications with real-time monitoring in 299, and after applications in 280 PVs by Achieve catheters alone. The time-to-isolation was 27.2 ± 22.0 seconds. Validation with standard circumferential mapping catheters confirmed ostial PVIs in 296 of 299 (99.0%) PVs that real-time PVI was obtained during applications, and in 242 of 280 (86.5%) PVs that PV activities were not visible during applications and PVI was verified after the applications. The accuracy of ostial PVIs with Achieve catheters in PVs without obtaining real-time PV recordings was 40/47 (85.1%), 58/65 (89.2%), 77/79 (97.5%), 61/81 (75.3%), and 6/8 (75.0%) in left superior, left inferior, right superior, right inferior, and left common PVs, respectively.

CONCLUSIONS: In second-generation 28-mm cryoballoon ablation, verification of ostial PVIs using Achieve mapping catheters alone might not be sufficient to accurately confirm an ostial PVI when real-time PVI was not obtained.