Left bundle branch area pacing compared to right ventricular outflow tract pacing: mid-term results and learning curve

FUNDING ACKNOWLEDGEMENTS: Type of funding sources: None. BACKGROUND: The aim was to evaluate efficacy and feasibility of left bundle branch area pacing (LBBAP) with right ventricle outflow tract pacing(RVOP), as well as describing the learning curve. METHODS: Prospective single-center observational study, including 200 patients that required pacemaker implantation. Two groups: LBBAP and RVOP with 100 patients each. Our aim was to compare safety and efficacy as well as the procedure and fluoroscopy times and to describe the LBBAP-learning curve. RESULTS: Success and acute complication rate were similar in both groups(p=0.56,p=0.65). Time for ventricular lead placement was higher in LBBAP group(18 [13-28] vs 11[7-17]min, p<0.001). Fluoroscopy time was lower in LBBAP, (2.8[1.3-3.7] vs 3.1[2-5.9]min, p=0.02). Paced-QRS was narrower in LBBAP group (122.9±13.7ms vs 145.7±17.6ms, p=0.002). There were no differences related to pacing parameters. In LBBAP group, procedure time was lower in the last quartile (Q4) compared to the first quartile (12 [10.5-15] vs 32[28.5-38.5]min, p<0.001) as well as fluoroscopy time (2[1-4.6] vs 5.1[3.4-12]min, p<0.01). Procedure time was similar between LBBAP-Q4 and RVOP (12[10.5-15] vs 11[7-17]min, p=0.33). CONCLUSIONS: LBBAP is as safe as RVOP and it achieved a narrower paced-QRS than RVOP. It requires a longer procedure time and a shorter fluoroscopy time, with a rapid learning curve. [Figure: see text] [Figure: see text]