Baseline characteristics and procedural data
During the study period, 644 patients underwent AF/AT ablation
procedures in our two centres, and 253 of them were performed with the
Rhythmiaâ„¢ system. Seven patients were lost to follow-up. Finally, 246
patients were included, 135 of them (54.9%) constituted the HF group
(Figure 1). In the HF group, 62 patients had preserved LVEF (46.3%),
and 72 (53.7%) had reduced LVEF. One patient was excluded from subgroup
analysis due to missing LVEF data.
The procedures were performed mostly in men (71.5%) with a median age
of 64 years old (56-69). The clinical characteristics are detailed in
Table 1. As expected, patients in the HF group had more comorbidities
and were more symptomatic. Arrhythmias were also unequally distributed
between the groups; AT and persistent AF were more frequent in the HF
group, whereas 20% of the patients in the non-HF group had paroxysmal
AF (p=0.005). The majority of the patients had already undergone a
previous CA (59.3%) with no difference between groups. Patients with HF
had more frequent history of non-PVI and non cavo-tricuspid isthmus
ablation (p=0.04).
Procedures in the HF group were longer (p=0.01), with longer fluoroscopy
duration (p<0.001), higher fluoroscopy dose
(p<0.001), more maps (p=0.017), and longer mapping time
(p<0.001), compared to procedures in the non-HF group.
Conversely, the number of recorded electrograms (p=0.714), the RF
duration (p=0.118), and the volume of infused serum (p=0.623) did not
differ between the groups. A total of 285 ATs were analysed, including
those occurring during ablation of persistent AF. Most of them were
macro-reentries (58.9%) while the mechanism of 33 ATs remained
undetermined (12.3%), with no difference between groups.