The fourth cryoballoon generation with a shorter tip to facilitate real-time pulmonary vein potential recording: Feasibility and safety results.
INTRODUCTION
Time-to-isolation (TTI) guided ablation protocols have been developed to ensure durable pulmonary vein isolation (PVI) in cryoballoon ablation (CBA). The aim was to determine the feasibility and safety of the fourth generation cryoballoon (CBG4) with a shortened tip.


METHODS AND RESULTS
Consecutive patients scheduled for initial atrial fibrillation (AF) ablation were prospectively included. PVI with the 28 mm CBG4 and the latest 20 mm spiral-mapping catheter (SMC) was performed. A total of 302 pulmonary veins (PVs) in 76 patients (64.8 ± 10.4 years, paroxysmal AF 49%) were treated with 617 applications. Left atrium (LA) time, fluoroscopy time, and dose-area product were 65.5 ± 19.2 minutes, 14.6 ± 5.6 minutes, and 1094 (738; 2097) cGy·cm2 , respectively. PVI in cryoballoon technique was achieved in 302 of 302 (100%) PVs. TTI was determined in 256 (84.8%) of PVs. The mean TTI was 45.3 ± 26.4 seconds. Single-shot isolation was achieved in 247 (82%) PVs. In 6 of 302 (2.0%) PV the SMC was changed to a stiff wire to isolate the PV because of instability, and in 17 of 302 (5.6%) of PVs, the 23 mm CB was used to isolate. No radiofrequency touch-up applications were applied. The mean nadir balloon temperature was -44.8°C ± 6.6°C. Balloon dislodgement during positioning occurred in 3 of 617 (0.5%) applications without complications. One PN palsy occurred which resolved until discharge. One patient suffered from the inflammatory syndrome.


CONCLUSION
The CBG4 with a shorter distal tip seems to be safe and effective, and allows determining the TTI in 84.8% of PVs. In case of balloon instability, the exchange of the SMC to a stiff wire or, in small PV, the 23 mm cryoballoon facilitate PVI.
['Straube|Florian|F|0000-0002-4491-5224', 'Dorwarth|Uwe|U|', 'Pongratz|Janis|J|', 'Brück|Benedikt|B|', 'Wankerl|Michael|M|', 'Hartl|Stefan|S|', 'Hoffmann|Ellen|E|']
D000200:Action Potentials D001281:Atrial Fibrillation D062906:Cardiac Catheters D017115:Catheter Ablation D003452:Cryosurgery D022062:Electrophysiologic Techniques, Cardiac D004867:Equipment Design D005240:Feasibility Studies D005260:Female D006339:Heart Rate D006801:Humans D008297:Male D008875:Middle Aged D061646:Operative Time D011237:Predictive Value of Tests D011667:Pulmonary Veins D012008:Recurrence D013997:Time Factors D016896:Treatment Outcome
cryoballoon atrial fibrillation catheter ablation spiral mapping catheter time to isolation