A comparison of acute procedural outcomes within four generations of cryoballoon catheters utilized in the real-world multicenter experience of 1STOP

Introduction: Four generations of the cryoballoon (CB) catheter were retrospectively evaluated in a real-world examination of patients with atrial fibrillation (AF). Methods and results: Four hundred eighty patients (27% female and 60 ± 10 years) suffering from AF, underwent pulmonary vein (PV) ablation with one-of-four generations of the CB catheter. The total cohort was divided into four groups of patients: 120 with first-generation (CB-1); 120 with second-generation (CB-2); 120 with third-generation (CB-3); and 120 with fourth-generation (CB-4). Equal group sizes were achieved by examining the last 120 patients treated in each cohort, attempting to minimize the effect of a learning curve between the generations of CB catheter. Baseline clinical and patient characteristics were similar between the four cohorts, excepting age and the number of tested antiarrhythmic drugs. Procedure, fluoroscopy, and left atrial dwell times were significantly lower in the CB-4 cohort compared to previous generations of the CB catheters, while the acute procedural success rate was comparable across all catheter groups (>99%). Total acute procedural complications were low (2.5%), and acute complications were comparable within the CB-2, CB-3, and CB-4 groups (0.8% reported in each cohort). The rate of time-to-isolation (TTI) visualization increased with later generations of the CB catheters. Conclusions: The novel CB-4 achieved significantly faster procedural ablation times in comparison to the previous generations, while still maintaining a low rate of acute complications. Also, the rate of TTI visualization was observed to be higher with the CB-4 catheter. Further long-term evaluation is necessary, including an assessment of AF recurrence and PV reconnection(s)