Impact of left atrial size on the ablation of atrial fibrillation using remote magnetic navigation

Abstract

Objective \nThe aim of this study was to investigate the impact of left atrial size on the ablation of atrial fibrillation (AF) using remote magnetic navigation (RMN) . \n \n \nMethods \nFrom August 2016 to August 2017, a total of 43 patients with AF who underwent catheter ablation using RMN in Wuxi People’s Hospital AF filiated to Nanjing Medical University were included. The patients were divided into two groups based on diameter of the left atrium. Sixteen patients had smaller left atrial size (left atrial diameter<40 mm,group A ), and the other 27 patients with left atrial diameter≥40 mm (group B). The parameters, just like procedure duration, X-ray time and dose during ablation, success rate and recurrence rate were compared between the two groups. \n \n \nResults \nCompared with group B, there were more patients with paroxysmal AF (15/16 vs.13/27, P=0.002) in group A. Left ventricular ejection fraction of group A was higher than that in Group B[63.9%±4.2% vs. 61.1%±3.6%, P=0.026) ]. The volume of the left atrial model built by Carto 3 in group A was smaller[ (91.8±15.7) ml vs. (119.6±31.8) ml, P=0.002]. During the ablation process, X-ray exposure time[ (77.3±115.9) s vs. (9.6±16.5) s, P<0.001]and X-ray dose[ (2.6±3.6) gycm2 vs. (1.0±2.5) gycm2, P=0.003 8) were significantly increased in group A. No serious complications occurred in all patients. There was no statistical difference in the acute success rate of pulmonary vein isolation between the two groups. However, compared with group B, the recurrence rate of group A was lower and the rate of maintain sinus rhythm was higher (93.8% vs.66.7%, P=0.04) during the follow-up. \n \n \nConclusions \nAtrial fibrillation ablation using RMN is safe and effective. However, Patients with smaller left atrial size may increase the difficulty of operation resulting in increased the exposure time and dose of X-rays. \n \n \nKey words: \nAtrial fibrillation;\xa0Catheter ablation;\xa0Atrial function, left