Focal impulse and rotor modulation as a stand-alone procedure for the treatment of paroxysmal atrial fibrillation: A within-patient controlled study with implanted cardiac monitoring

Background Focal impulse and rotor modulation (FIRM) has been proposed as a novel approach for the treatment of atrial fibrillation (AF). Objective This study aimed to investigate the efficacy of FIRM as a stand-alone procedure for the treatment of paroxysmal AF. Methods A total of 27 patients with paroxysmal AF underwent sequential biatrial computational mapping. Sites with repetitive centrifugal or spiral reentry-like activity were considered to be AF-sustaining sources and targeted by irrigated radiofrequency (RF) ablation. All patients were seen in the outpatient clinic after 1, 3, and 6 months and thereafter every 6 months. Cardiac monitors were implanted 3 months before ablation in 17 patients (63%). Results Repetitive activity interpreted as sustained AF sources was found in all patients, with an average of 3.0 ± 1.1 sources located in the left atrium and 0.6 ± 0.6 sources in the right atrium. The majority of sources were rotors (95%). The total source-ablation radiofrequency time was 20.0 ± 9.0 minutes. At 15.2 ± 3.9 months of follow-up, the prespecified end point of