Results:
A total of 32 consecutive patients with drug refractory paroxysmal or persistent atrial fibrillation referred for a first or redo ablation were enrolled in the present study (Table 1). In 18 patients the m-FAM reconstruction was conducted with the use of the ablation catheter only (Group 1), while a Pentaray and ablation catheter were used in 14 patients (Group 2). The CTA of the patients enrolled showed a classical anatomy with 4 pulmonary veins in 66% of the patients, while a left common ostium and a right middle branch was seen in 25% and 21% patients, respectively (table 2).
The m-FAM time was significantly shorter in group 2 while the m-Fam fluoroscopy time was similar for the two groups. In 4 out of 32 patients (12%) enrolled, regardless the mapping catheter used for the reconstruction re acquisition of the magnet points at the PV ostium and LA body was required to optimize the reconstruction.
The m-FAM reconstruction accuracy was accurate also in patients with left common pulmonary veins or right middle branches as in patients with a classical left atrial anatomy. In case of a right middle branch, the m-FAM reconstruction displayed the additional branches as part of the right superior right inferior PV. Regardless to the pulmonary vein anatomy, the PV antrum at the level of the WACA was accurately reconstructed.
The visual comparison between the m-FAM and the CT scan was good in all patients before initiating the ablation. In the four patients in whom the initial m-FAM reconstruction was inaccurate based on the confirmation of the PV landmarks with fluoroscopy and ICE, the comparison with the CT scan was also poor and became good after re acquisition of the magnet landmarks and re initiation of the m-FAM software.
All pulmonary vein ablated were successfully isolated. The fluoroscopy time, dwell time, procedural time and radiofrequency time were similar for the two groups (Table 2).
No significant complications occurred during or after the procedure.