Single versus double transeptal puncture: characterization and outcomes in a single tertiary center

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. [Figure: see text] [Figure: see text]