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.