Single Versus Double Transeptal Puncture: Characterization and Outcomes in a Single Tertiary Center

Abstract Funding Acknowledgements Type of funding sources: None. Background An ablation catheter in conjunction with a circular mapping catheter (CMC) requiring a double transeptal puncture (TSP) for left atrial access is conventionally used for atrial fibrillation (AF) ablation in the majority of centers. In the recent years, different operators have combined a single transseptal puncture technique with 3D high-density mapping catheters for pulmonary veins isolation (PVI) in AF patients. Objective The aim of this analysis is to compare two different strategies, single versus double TSP, regarding duration of the procedure, radiation dose, complications and long-term outcomes. Methods Retrospective analysis of an AF large cohort of consecutive patients that underwent PVI with radiofrequency energy (RF) using a 3D mapping system, either with single or double TSP, from 2016 to 2020. Results We included 341 patients (female 35,8 %, paroxysmal AF 64,2 %) who underwent catheter ablation with RF. At the time of the ablation, age was 59,1 ± 11,8 years old, and the mean CHA2DS2-VASc score was 1,6 ± 1,3. All patients were taking oral anticoagulation. Single TSP was performed in 165 (48,4%%) patients and double TSP in 176 (51,6%) patients. In 56 (16,4%) cases (50 [30,3%] in the single TSP and 6 [3,4%] in the double TSP), the procedure was a repeat ablation after AF recurrence. Operator experience (defined as ≥5 years of AF ablation procedures) was equally distributed between the two groups. The average procedure time single (129 ± 33,2 minutes vs. 122 ± 34,9 minutes, for single and double TSP, respectively) did not reach statistical difference between the two groups (p = 0,55), but there was a significant difference regarding fluoroscopy time (13 ± 6,3 vs. 19 ± 9,1, for single and double TSP, respectively; p < 0,001). Acute complications were less frequent in the single TSP approach (5,6 % vs. 9,7 %, for single and double TSP, respectively), but did not reach statistical significance. At 2-year follow-up, sinus rhythm maintenance rate was similar in both groups (77% vs. 78%, p=0,85). At 2 and 4 year follow-up, the Kaplan-Meier survival curves revealed no difference in time to AF recurrence between the two groups (log- rank p = 0,974 and p = 0,965). However, further analysis of subgroups according to type of AF revealed a significant difference among the subgroup with persistent AF submitted to double TSP (log rank p = 0,007) during a total of follow-up of 4 years. Conclusion A simplified single-TSP technique using high-density multi-electrode 3D mapping is a safe and highly successful approach for AF ablation. This approach yields a substantial reduction in fluoroscopy time, with the potential to avoid acute complications when compared to a conventional double-TSP strategy.