Significant reduction of radiation exposure in cryoballoon-based pulmonary vein isolation.

Aims: Procedure times and left atrial dwell times of cryoballoon (CB)-based ablation strategies for atrial fibrillation (AF) are shorter as compared to radiofrequency ablation, yet fluoroscopy times are longer and result in a higher radiation exposure. The objective of this study is to evaluate a modified fluoroscopy protocol aiming at reduction of radiation exposure in CB ablation. Methods and results: A total of 120 patients with symptomatic AF underwent pulmonary vein isolation (PVI) using the second generation CB and an ablation strategy considering the individual time-to-isolation. The first 60 patients (Group 1) underwent CB-based PVI with conventional fluoroscopy settings. An optimized approach was applied in the following 60 patients (Group 2) by (i) using fluoroscopy instead of filming for verification of pulmonary vein (PV) occlusion after contrast injection, (ii) reducing the frame rate, and (iii) pursuing maximal collimation on the region of interest. A total of 475 PVs were identified and successfully isolated. Median dose area product and fluoroscopy time were significantly shorter in Group 2 as compared to Group 1 [389 (285; 550) cGycm2 vs. 2168 (1355; 3490) cGycm2 (P < 0.0001) and 10 (8; 12) min vs. 14 (11; 19) min (P < 0.0001)]. Additionally, median time-to-isolation of the PVs was significantly shorter in Group 2 [44 (30; 65) s vs. 33 (20; 46) s (P < 0.0001)]. Conclusions: The implementation of an optimized fluoroscopy protocol significantly reduces radiation exposure in CB-based PVI without compromising acute efficacy and safety.