Anatomic Parameters Predicting Procedural Difficulty and Balloon Temperature Predicting Successful Applications in Individual Pulmonary Veins During 28-mm Second-Generation Cryoballoon Ablation.

OBJECTIVES: This study sought to identify anatomic parameters predicting procedural difficulty in achieving pulmonary vein isolation (PVI) and in-procedural predictors of successful applications during second-generation cryoballoon (CB) ablation.

BACKGROUND: PV anatomies vary and influence the procedural difficulty during CB PVI.

METHODS: In total, 408 initial freezes among 110 patients undergoing PVI for paroxysmal atrial fibrillation using 28-mm second-generation CBs with single 3-min freeze techniques were included. The anatomic parameters were obtained from pre-procedural cardiac computed tomography. The nadir balloon temperature and temperature at the start of the plateau phase were recorded during each freeze.

RESULTS: Acute PVI was achieved by initial applications in 335 pulmonary veins (PVs) (82.1%) and touch-up was required in 13 (3.2%). A multivariate analysis revealed that a thinner left lateral ridge (<4.7 mm), higher ovality (>50.5%), and longer PV ostium-bifurcation distance (>26.1 mm) required multiple applications for a successful left superior PVI. Older age (>68 years), and shorter PV ostium-bifurcation distance (<10.4 mm) required multiple applications for a successful right superior and right inferior PVI, respectively. Shorter PVTLs were also associated with requiring touch-up of the RIPV. Balloon temperatures were lower for successful than failed PVI applications. Successful PVIs were predicted using the nadir balloon temperature at 33.0 ± 2.6 s, 33.0 ± 2.5 s, 33.6 ± 2.5 s, and 33.0 ± 2.5 s from the initiation of freezes with positive predictive values of 87.7%, 88.5%, 98.5%, and 81.6% using cutoff temperatures of -34°C, -33°C, -37°C, and -33°C in the left superior, left inferior, right superior, and right inferior PVs, respectively.

CONCLUSIONS: The anatomic information might predict procedural difficulty and the balloon temperature a successful PVI during the early CB ablation freezing phase.