INTRODUCTION
Congestive heart failure (HF) and atrial fibrillation (AF), two major
cardiovascular conditions, often coexist. Patients with HF usually have
chronically elevated filling pressures, that favour left atrial
enlargement and atrial arrhythmias, either AF or atrial tachycardia (AT)
occurrence. Besides, AF worsens their functional capacity and increases
mortality, regardless of whether they have preserved or reduced left
ventricular ejection fraction (LVEF).1,2 Catheter
ablation (CA) of AF in a setting of HF with reduced LVEF is safe, and
has proven effectiveness in improving functional status, quality of
life, LVEF,3–5 and mortality.6 Data
regarding CA for AF in case of HF with preserved LVEF (HFpEF) are
limited but encouraging. 7,8 AF and AT often coexist
as they shared risk factors and underlying substrate, especially in HF.
Nevertheless, these procedures can be challenging in HF patients, who
are likely to experience more recurrences, and repeated ablations than
patients with normal cardiac function, despite the use of
three-dimensional electroanatomic (3D) mapping systems.7,9 The novel ultra-high-density (UHD) mapping system
(Rhythmia™, Boston Scientific, Inc., Marlborough, MA, USA) using a
dedicated 64-pole mini-basket catheter (IntellaMap Orion™, Boston
Scientific) has been now widely used, enabling rapid and accurate
mapping with low signal/noise ratio and limited need for additional
manual editing. Several studies have reported the ability of this system
to elucidate complex arrhythmias. 10,11 However, data
about clinical use of this UHD mapping system in HF patients are scarce,
and whether this UHD system could improve CA results, with no clear data
on safety in this particular population is unknown. The aim of our study
was to assess clinical outcomes after Rhythmia™-guided ablation
procedures of complex atrial arrhythmias in patients with clinical HF
with and without reduced LVEF, compared to patients normal LVEF and no
HF.