Background: High-frequency low-tidal-volume (HFLTV) ventilation is a safe and cost-effective strategy that improves catheter stability, first-pass pulmonary vein isolation, and freedom from all-atrial arrhythmias during radiofrequency catheter ablation (RFCA) of paroxysmal and persistent atrial fibrillation (AF). However, the incremental value of adding rapid-atrial pacing (RAP) to HFLTV-ventilation has not yet been determined. Objective: To evaluate the effect of HFLTV-ventilation plus RAP during RFCA of paroxysmal AF on procedural and long-term clinical outcomes compared to HFLTV-ventilation alone. Methods: Patients from the REAL-AF prospective multicenter registry, who underwent RFCA of paroxysmal AF using either HFLTV+RAP (500-600 msec) or HFLTV ventilation alone from April 2020 to February 2023 were included. The primary outcome was freedom from all-atrial arrhythmias at 12-month follow-up. Secondary outcomes included procedural characteristics, long-term clinical outcomes, and procedure-related complications. Results: A total of 545 patients were included in the analysis (HFLTV+RAP=327 vs. HFLTV=218). There were no significant differences in baseline characteristics between the groups. No differences were observed in procedural (HFLTV+RAP 74 [57-98] vs. HFLTV 66 [53-85.75] min, p=0.617) and RF (HFLTV+RAP 15.15 [11.22-21.22] vs. HFLTV 13.99 [11.04-17.13] min, p=0.620) times. Both groups showed a similar freedom from all-atrial arrhythmias at 12-month follow-up (HFLTV+RAP 82.68% vs. HFLTV 86.52%, HR=1.43, 95% CI [0.94-2.16], p=0.093). There were no significant differences in freedom from AF-related symptoms (HFLTV+RAP 91.4% vs. HFLTV 93.1%, p=0.476) or AF-related hospitalizations (HFLTV+RAP 98.5% vs. HFLTV 97.2%, p=0.320). Procedure-related complications were low in both groups (HFLTV+RAP 0.6% vs. HFLTV 0%, p=0.247). Conclusion: In patients undergoing RFCA for paroxysmal AF, adding RAP to HFLTV-ventilation was not associated with improved procedural and long-term clinical outcomes.

Background: Left atrial appendage occlusion (LAAO) has historically been performed using intraprocedural transesophageal echocardiography (TEE) and fluoroscopy. Multiple recent reports have described the feasibility and advantages of utilizing two-dimensional intracardiac echocardiography (ICE) for LAAO. However, in inexperienced hands, safe manipulation of the ICE catheter in the left atrium (LA) can be challenging. Objective: To assess the feasibility and efficacy of three-dimensional (3D) ICE mapping in guiding LAAO device implant compared to standard TEE imaging. Methods: We retrospectively included patients who underwent LAAO in our institution from January 2017 and October 2021. We compared baseline demographics, intraprocedural data, post-procedural complications, and outcomes. P= value of <0.05 was considered significant. A linear regression model was performed using ICE and TEE as dependent variables to model contrast dose. Results: 130 patients underwent LAAO device implantation, of which 57 underwent ICE guided LAAO and 73 underwent TEE guided implantation. There was no difference in baseline demographics or post-procedural outcomes between both groups. There was no difference in the total procedure time between ICE and TEE groups, 86 (72-107) and 83 (72-111) minutes (p=0.65), respectively. Conversely, total fluoroscopic time was significantly shorter in ICE arm 7.8 (5.6-11), compared to TEE arm 12.9 (10.5-17.6) (p= <0.001). In patients undergoing LAAO device implantation using 3D ICE technique, with each additional ICE-guided procedure, the contrast dose decreased by 0.87 mL (correlation r = -0.48, p<0.001). Conclusion: 3D ICE is safe and feasible in guiding LAAO device implantation. When compared to TEE technique, total fluoroscopic time was shorter. Additionally, with more procedures utilizing 3D ICE, contrast dose decreased in a linear fashion.